DESCRIPTION
[Title of Invention]
RECORDING MEDIUM, REPRODUCTION DEVICE, AND INTEGRATED
CIRCUIT
[Technical Field]
[0001] The present invention relates to a technology for stereoscopic, i.e.
three-dimensional (3D), video playback and especially to decoding of the video
stream.
[Background Art]
[0002] In recent years, general interest in 3D video has been increasing. For example,
amusement park attractions that incorporate 3D video images are popular.
Furthermore, throughout the country, the number of movie theaters showing 3D
movies is increasing. Along with this increased interest in 3D video, the
development of technology that enables playback of 3D video images in the home
has also been progressing. There is demand for this technology to store 3D video
content on a portable recording medium, such as an optical disc, while maintaining
the 3D video content at high image quality. Furthermore, there is demand for the
recording medium to be compatible with a two-dimensional (2D) playback device.
That is, it is preferable for a 2D playback device to be able to play back 2D video
images and a 3D playback device to be able to play back 3D video images from the
same 3D video content recorded on the recording medium. Here, a "2D playback
device" refers to a conventional playback device that can only play back
monoscopic video images, i.e. 2D video images, whereas a "3D playback device"
refers to a playback device that can play back 3D video images. Note that in the
present description, a 3D playback device is assumed to be able to also play back
conventional 2D video images.
[0003] FIG 100 is a schematic diagram illustrating the technology for ensuring the
compatibility of an optical disc storing 3D video content with 2D playback devices
(see Patent Literature 1). An optical disc 9201 stores two types of video stream files.
One is a 2D/left-view video stream file, and the other is a right-view video stream
file. A "2D/left-view video stream" represents a 2D video image to be shown to the
left eye of a viewer during 3D playback, i.e. a "left-view". During 2D playback, this
stream constitutes the 2D video image. A "right-view video stream" represents a 2D
video image to be shown to the right eye of a viewer during 3D playback, i.e. a
"right-view". The left and right video streams have the same frame rate but different
presentation times shifted from each other by half a frame period. For example,
when the frame rate of each video stream is 24 frames per second, the frames of the
2/D left-view video stream and the right-view video stream are alternately displayed
every 1/48 seconds.
[0004] As shown in FIG. 100, the left-view and right-view video streams are divided
into a plurality of extents 9202A-C and 9203A-C respectively on the optical disc
9201. Each extent contains at least one group of pictures (GOP), GOPs being read
together from the optical disc. Hereinafter, the extents belonging to the 2D/left-view
video stream are referred to as "2D/left-view extents", and the extents belonging to
the right-view video stream are referred to as "right-view extents". The 2D/left-view
extents 9202A-C and the right-view extents 9203A-C are alternately arranged on a
track 9201A of the optical disc 9201. Each two adjacent extents 9202A-9203A,
9202B-9203B, and 9202C-9203C have the same length of playback time. Such an
arrangement of extents is referred to as an interleaved arrangement. A group of
extents recorded in an interleaved arrangement on a recording medium is used both
in 3D video playback and 2D video image playback, as described below.
[0005] From among the extents recorded on the optical disc 9201, a 2D playback
device 9204 causes an optical disc drive 9204A to read only the 2D/left-view extents
9202A-C sequentially from the start, skipping the reading of right-view extents
9203A-C. Furthermore, an image decoder 9204B sequentially decodes the extents
read by the optical disc drive 9204A into a video frame 9206L. In this way, a display
device 9207 only displays left-views, and viewers can watch normal 2D video
images.
[0006] A 3D playback device 9205 causes an optical disc drive 9205 A to alternately
read 2D/left-view extents and right-view extents from the optical disc 9201. When
expressed as codes, the extents are read in the order 9202A, 9203A, 9202B, 9203B,
9202C, and 9203C. Furthermore, from among the read extents, those belonging to
the 2D/left-view video stream are supplied to a left video decoder 9205L, whereas
those belonging to the right-view video stream are supplied to a right-video decoder
9205R. The video decoders 9205L and 9205R alternately decode each video stream
into video frames 9206L and 9206R, respectively. As a result, left-views and
right-views are alternately displayed on a display device 9208. In synchronization
with the switching of the views by the display device 9208, shutter glasses 9209
cause the left and right lenses to become opaque alternately Therefore, a viewer
wearing the shutter glasses 9209 sees the views displayed by the display device
9208 as 3D video images.
[0007] When 3D video content is stored on any recording medium, not only on an
optical disc, the above-described interleaved arrangement of extents is used. In this
way, the recording medium can be used both for playback of 2D video images and
3D video images.
[Citation List]
[Patent Literature]
[0008] [Patent Literature 1]
Japanese Patent No. 3935507
[Summary of Invention]
[Technical Problem]
[0009] In the technology for playback of 3D video images shown in FIG. 100, as
described above, a pair of left-view and right-view frame data is necessary to display
one frame of a 3D video image. Accordingly, the 3D playback device 9205 is
required to have at least twice the processing speed of the 2D playback device 9204.
The decoding of stream data places a particularly large burden on the playback
device, and reducing this burden is extremely effective in increasing reliability of the
playback device.
[0010] It is an object of the present invention both to provide a recording medium
that stores stream data, which represents 3D video images, in a data structure that
reduces the processing burden on the playback device for decoding the stream data,
and to provide a playback device that offers increased reliability by performing the
decoding processing efficiently.
[Solution to Problem]
[0011] A main-view stream and a sub-view stream are recorded on a recording
medium according to an embodiment of the present invention. The main-view
stream is used for monoscopic video playback, and the sub-view stream is used for
stereoscopic video playback in combination with the main-view stream. The
main-view stream includes a plurality of main-view pictures, and the sub-view
stream includes a plurality of sub-view pictures.
[0012] On a recording medium according to a first aspect of the present invention,
the main-view pictures and the sub-view pictures are in one-to-one correspondence.
When a sub-view picture corresponds to a main-view picture that is one of an I
picture and a P picture, any reference picture used for compression of the sub-view
picture is one of an I picture and a P picture.
[0013] On a recording medium according to a second aspect of the present invention,
the main-view stream further includes at least one main-view picture header, and the
sub-view stream further includes at least one sub-view picture header. Each
main-view picture header includes information indicating a coding method of a
main-view picture. Each sub-view picture header includes information indicating a
coding method of a sub-view picture. Each main-view picture refers to the
main-view picture header but does not refer to the sub-view picture header. Each
sub-view picture refers to the sub-view picture header but does not refer to the
main-view picture header.
[0014] A playback device according to an embodiment of the present invention is a
playback device for playing back video images from a main-view stream and a
sub-view stream and comprises a decoding unit and a control unit. The main-view
stream is used for monoscopic video playback. The sub-view stream is used for
stereoscopic video playback in combination with the main-view stream. The
decoding unit is operable to extract a compressed picture from each of the
main-view stream and the sub-view stream, analyze a header included in the
compressed picture, and decode the compressed picture. The control unit is operable
to determine a decoding method of the compressed picture from the header of the
compressed picture analyzed by the decoding unit and indicate the decoding method
to the decoding unit. During a period when the control unit determines the decoding
method of a compressed picture included in the main-view stream from the header
of the compressed picture, the decoding unit performs one of header analysis and
decoding of a compressed picture included in the sub-view stream. During a period
when the control unit determines the decoding method of a compressed picture
included in the sub-view stream from the header of the compressed picture, the
decoding unit decodes a compressed picture included in the main-view stream.
[Advantageous Effects of Invention]
[0015] In the recording medium according to the first aspect of the present invention,
when an I picture or P picture is selectively decoded from the main-view stream, a
3D video image can be played back if the corresponding picture is decoded from the
sub-view stream. Accordingly, this recording medium can reduce the processing
burden on the playback device for decoding stream data, particularly during
trickplay of 3D video images. On the other hand, in the recording medium according
to the second aspect of the present invention, a main-view picture and sub-view
picture do not refer to each other's picture headers. Accordingly, the recording
medium can further reduce the processing burden on the 3D playback device for
determining the coding method of each picture.
[0016] In a playback device according to the above embodiments of the present
invention, while the decoding unit is decoding a picture, the control unit determines
the decoding method for the next picture. As a result, the playback device can
decode stream data more efficiently, thereby increasing reliability.
[Brief Description of Drawings]
[0017] FIG. 1 is a schematic diagram showing a home theater system that uses a
recording medium according to embodiment 1 of the present invention.
FIG. 2 is a schematic diagram showing the data structure of a BD-ROM
disc 101 according to embodiment 1 of the present invention.
FIG. 3A is a list of elementary streams multiplexed in the main TS on the
BD-ROM disc 101 shown in FIG. 2, FIG. 3B is a list of elementary streams
multiplexed in the first sub-TS on this BD-ROM disc 101, and FIG. 3C is a list of
elementary streams multiplexed in the second sub-TS on this BD-ROM disc.
FIG. 4 is a schematic diagram showing the arrangement of TS packets
belonging to each elementary stream shown in FIG. 3A.
FIG. 5A is a schematic diagram showing the data structure of a header for
each TS packet shown in FIG. 4, FIG. 5B is a schematic diagram of a TS packet
sequence, FIG. 5C is a schematic diagram of a source packet sequence composed of
the TS packet sequence, and FIG. 5D is a schematic diagram of a sector group, in
which a sequence of source packets are consecutively recorded, in a volume area of
a BD-ROM disc.
FIG. 6 is a schematic diagram showing, in order of presentation time, three
pictures 601, 602, and 603 included in a video stream.
FIG. 7 is a schematic diagram showing the picture groups respectively
included in the base-view video stream shown in FIG. 3A and in the right-view
video stream shown in FIG. 3B in order of presentation time.
FIG. 8 is a schematic diagram showing the picture groups respectively
included in the base-view video stream shown in FIG. 3A and in the depth map
stream shown in FIG. 3C in order of presentation time.
FIG. 9 is a schematic diagram showing the data structure of the top section
of a video sequence included in a video stream.
FIG. 10 is a schematic diagram showing the data structure of the end section
of the video sequence shown in FIG. 9.
FIG. 11 is a schematic diagram showing the method for storing a video
stream 1101 into a PES packet sequence 1102.
FIG. 12A is a schematic diagram showing the relationship between the
PTSs and DTSs assigned to each picture in a base-view video stream 1201, and FIG.
12B is a schematic diagram showing the relationship between the PTSs and DTSs
assigned to each picture in a dependent-view video stream 1202.
FIG. 13 is a schematic diagram showing the data structure of supplementary
data 93ID shown in FIG. 9.
FIGS. 14A and 14B are schematic diagrams showing two examples of
decoding counters assigned to each picture in the base-view video stream 1401 and
in the dependent-view video stream 1402.
FIG. 15 is a schematic diagram showing the physical arrangement on a
BD-ROM disc of data block groups belonging to the main TS, first sub-TS, and
second sub-TS shown in FIGS. 3A, 3B, and 3C.
FIG. 16A is a schematic diagram showing the arrangement of a main TS
1601 and sub-TS 1602 recorded separately and contiguously on a BD-ROM disc,
and FIG. 16B a schematic diagram showing the interleaved arrangement of the
base-view data blocks B[0], B[l], B[2], ... and dependent-view data blocks D[0],
D[l], D[2], ... recorded on a BD-ROM disc according to embodiment 1 of the
present invention.
FIGS. 17A and 17B are schematic diagrams showing two examples of
extent ATC times for a dependent-view data block group D[0], D[l], D[2] and a
base-view data block group B[0], B[l], B[2] recorded in an interleaved arrangement.
FIG. 18 is a schematic diagram showing a playback path 1801 in 2D
playback mode, playback path 1802 in L/R mode, and playback path 1803 in depth
mode for the data block groups shown in FIG. 15.
FIG. 19 is a schematic diagram showing the data structure of a PMT 1910.
FIG. 20 is a schematic diagram showing the data structure of the 2D clip
information file (OlOOO.clip) 231 shown in FIG. 2.
FIG. 21A is a schematic diagram showing the data structure of the entry
map 2030 shown in FIG. 20, FIG. 2IB is a schematic diagram showing source
packets in a source packet group 2110 belonging to the file 2D 241, shown in FIG. 2,
that are associated with each EP_ID 2105 by the entry map 2030, and FIG. 21C is a
schematic diagram showing the relationships between the source packet group 2110
and the data block group Dn, Rn, Ln (n = 0, 1,2,3,...) on a BD-ROM disc.
FIG. 22A is a schematic diagram showing the data structure of an offset
table 2041, and FIG. 22B is a schematic diagram showing the valid section of an
offset entry.
FIG. 23A is a schematic diagram showing the data structure of the extent
start points 2042 shown in FIG. 20, FIG. 23B is a schematic diagram showing the
data structure of extent start points 2320 included in the right-view clip information
file (02000. clpi) shown in FIG. 2, FIG. 23C is a schematic diagram representing the
base-view data blocks LI, L2, ... extracted from the first file SS (OlOOO.ssif) 244A
shown in FIG. 2 by the playback device 102 in L/R mode, FIG. 23D is a schematic
diagram representing the relationship between right-view extents EXT2[0], EXT2[1],
... belonging to the first file DEP (02000.m2ts) 242 shown in FIG. 2 and the SPNs
2322 shown by the extent start points 2320 shown in FIG. 23B, and FIG. 23E is a
schematic diagram showing an example of the relationship between 3D extents
EXTSS[0], EXTSS[l], ... belonging to the first file SS 244A and a data block group
2350onaBD-ROMdisc.
FIG. 24 is a schematic diagram showing an example of the relationships
between each extent group in a data block group 2400, file 2D 2410, file base 2411,
file DEP 2412, and file SS 2420 which include 3D video content and are recorded
on a BD-ROM disc according to embodiment 1 of the present invention.
FIG. 25 is a schematic diagram showing an example of entry points set in a
base-view video stream 2510 and a dependent-view video stream 2520 on a
BD-ROM disc according to embodiment 1 of the present invention.
FIG. 26 is a schematic diagram showing the data structure of the 2D playlist
file (00001.mpls) shown in FIG. 2.
FIG. 27 is a schematic diagram showing the data structure of the PI #N
shown in FIG. 26.
FIGS. 28A and 28B are schematic diagrams showing the relationship
between playback sections 2801 and 2802 that are to be connected when the
connection condition 2704 shown in FIG. 27 respectively indicates "5" and "6".
FIG. 29 is a schematic diagram showing the relationships between the PTSs
indicated by the 2D playlist file 221 shown in FIG. 26 and the sections played back
from the file 2D (01000.m2ts) 241 shown in FIG. 2.
FIG. 30 is a schematic diagram showing the data structure of the 3D playlist
file (00002.mpls) 222 shown in FIG. 2.
FIG. 31 is a schematic diagram showing the data structure of the STN table
SS 3030 shown in FIG. 30.
FIGS. 32A, 32B, and 32C are schematic diagrams respectively showing the
data structures of a stream registration information sequence 3112 for
dependent-view video streams, stream registration information sequence 3113 for
PG streams, and stream registration information sequence 3114 for IG streams,
which are shown in FIG. 31.
FIG. 33 is a schematic diagram showing the relationships between the PTSs
indicated by the 3D playlist file (00002.mpls) 222 shown in FIG. 30 and the sections
played back from the first file SS (01000.ssif) 244A shown in FIG. 2.
FIG. 34 is a schematic diagram showing an index table 3410 in the index
file (index.bdmv) 211 shown in FIG. 2.
FIG. 35 is a flowchart of selection processing for a playlist file to be played
back, the processing being performed when a 3D video title is selected by the
playback device 102 according to embodiment 1 of the present invention.
FIG. 36 is a functional block diagram of the playback device 102 according
to embodiment 1 of the present invention in 2D playback mode.
FIG. 37 is a list of system parameters in the player variable storage unit
3608 shown in FIG. 36.
FIG. 38 is a functional block diagram of the system target decoder 3603
shown in FIG. 36.
FIG. 39A is a schematic diagram showing the flow of data processed by a
decoder driver 3637 and DEC 3804 during decoding of the primary video stream by
the 2D playback device shown in FIGS. 36 and 38, and FIG. 39B is a schematic
diagram showing the decoding processing.
FIG. 40 is a functional block diagram of the playback device 102 according
to embodiment 1 of the present invention in 3D playback mode.
FIG. 41 is a functional block diagram of the system target decoder 4023
shown in FIG. 40.
FIG. 42A is a schematic diagram showing the flow of data processed by a
decoder driver 4037 and DEC 4104 during decoding of a pair of base-view and
dependent-view primary video streams by the 3D playback device shown in FIGS.
40 and 41, and FIG. 42B is a schematic diagram showing the decoding processing.
FIG. 43 is a functional block diagram of the plane adder 4024 shown in FIG.
40.
FIGS. 44A and 44B are schematic diagrams showing cropping processing
by the second cropping processing unit 4332 shown in FIG. 43.
FIGS. 45A, 45B, and 45C are schematic diagrams respectively showing the
left-view and right-view PG planes generated by the cropping processing shown in
FIG. 44, as well as the 3D video image perceived by a viewer based on these PG
planes.
FIG. 46 is a schematic diagram showing reference relationships between
headers of VAUs respectively found in a base-view video stream and
dependent-view video stream according to modification [B] of embodiment 1 of the
present invention.
FIG. 47 is a schematic diagram showing the structure of a primary video
decoder 4715, which is for decoding the video stream shown in FIG. 46.
FIG. 48 is a schematic diagram showing the data structure of a PMT 4810 to
which data related to the playback method of 3D video images has been added.
FIG. 49A is a schematic diagram showing the playback path when the
extent ATC times and the playback times of the video stream differ between
contiguous base-view data blocks and dependent-view data blocks, and FIG. 49B is
a schematic diagram showing a playback path when the playback times of the video
stream are equal for contiguous base-view and dependent-view data blocks.
FIG. 50 is a schematic diagram showing the relationships between entry
points and a data block group in an interleaved arrangement when the number of
entry points is the same between contiguous base-view and dependent-view data
blocks.
FIGS. 51A-51F are schematic diagrams showing conditions on setting a
sequence end code for multiplexed stream data played back according to a main path
in a 2D playlist file.
FIG. 52 is a schematic diagram showing the data structure of a TS packet
sequence storing a VAU #N in a base-view video stream for which a sequence end
code is set.
FIG. 53 is a functional block diagram of a system target decoder 5310 in a
3D playback device according to modification [I] of embodiment 1 of the present
invention.
FIG. 54 is a schematic diagram showing the order of decoding, by the
system target decoder 5301 shown in FIG. 53, of a base-view video stream VAU
5401 and a dependent-view video stream VAU 5402.
FIG. 55 is a schematic diagram showing the playback processing system in
the playback device 102 in 2D playback mode shown in FIG. 36.
FIG. 56A is a graph showing the change in a data amount DA stored in a
read buffer 3621 during operation of the playback device 102 in 2D playback mode
shown in FIG. 55, and FIG. 56B is a schematic diagram showing the relationship
between a data block group 5610 for playback and a playback path 5620 in 2D
playback mode.
FIG. 57 is an example of a correspondence table between jump distances
Sjump and maximum jump times TJUMP_max for a BD-ROM disc.
FIG. 58 is a schematic diagram showing the playback processing system in
the playback device 102 in 3D playback mode shown in FIG. 40.
FIGS. 59A and 59B are graphs showing the change in data amounts DA1
and DA2 stored in read buffers 4021 and 4022 when the playback device 102 shown
in FIG. 58 operates in L/R mode, and FIG. 59C is a schematic diagram showing the
relationship between a data block group 5910 for playback and a playback path 5920
in L/R mode.
FIGS. 60A and 60B are graphs showing the change in the data amounts
DA1 and DA2 stored in the read buffers 4021 and 4022 when the playback device
102 shown in FIG. 58 operates in depth mode, and FIG. 60C is a schematic diagram
showing the relationship between a data block group 6010 for playback and a
playback path 6020 in depth mode.
FIG. 61 is a schematic diagram showing a playback processing system
when the playback device 102 in 3D playback mode according to the present
invention uses a single read buffer.
FIG. 62A is a schematic diagram showing a playback path 6220 in L/R
mode for a data block group 6210 in an interleaved arrangement, and FIG. 62B is a
schematic diagram showing changes in the area in which data is stored in a read
buffer 6101 when the playback device 102 shown in FIG. 61 operates in accordance
with a playback path 6220 shown in FIG. 62A.
FIG. 63A is a graph showing changes in the data amount DA stored in the
read buffers 6101, 4021, and 4022 when the playback processing systems shown in
FIGS. 58 and 61 read a data block group 6310 in an interleaved arrangement
according to a playback path 6320 in L/R mode for a data block group 6310, and
FIG. 63B is a schematic diagram showing a playback path 6320.
FIG. 64 is a schematic diagram showing settings of ATSs for each
base-view and dependent-view extent read by the playback processing system
shown in FIG. 61.
FIG. 65A is a schematic diagram showing a data block group in an
interleaved arrangement that includes only multiplexed stream data, the data block
group being recorded on the BD-ROM disc 101 according to embodiment 1 of the
present invention, and FIG. 65B is a schematic diagram showing a data block group
in an interleaved arrangement that includes extents belonging to a different file than
the multiplexed stream data, the data block group being recorded on the BD-ROM
disc 101 according to modification [L] of embodiment 1 of the present invention.
FIG. 66 is a schematic diagram showing long jumps JLy, Jbdj1, and JBdj2
occurring when the playback device 102 according to embodiment 1 of the present
invention performs playback processing in L/R mode.
FIG. 67A is a schematic diagram showing data block groups 6701 and 6702
recorded before and after a layer boundary LB on a BD-ROM disc 101 according to
embodiment 1 of the present invention, and FIG 67B is a schematic diagram
showing playback paths 6710, 6711, and 6712 in each playback mode for 3D extent
blocks 6701 and 6702.
FIG. 68A is a schematic diagram showing a first example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101 according to embodiment 1 of the present invention, and FIG.
68B is a schematic diagram showing a playback path 6810 in 2D playback mode,
playback path 6820 in L/R mode, and a playback path 6830 in depth mode for the
data block groups shown in FIG. 68A.
FIG. 69 is a schematic diagram showing arrangement 1 in FIG. 68A with
the depth map data blocks removed.
FIG. 70A is a schematic diagram showing a second example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101 according to embodiment 1 of the present invention, and FIG.
70B is a schematic diagram showing a playback path 7010 in 2D playback mode,
playback path 7020 in L/R mode, and a playback path 7030 in depth mode for the
data block groups shown in FIG. 70A.
FIG. 71A is a schematic diagram showing a third example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101 according to embodiment 1 of the present invention, and FIG.
7IB is a schematic diagram showing a playback path 7110 in 2D playback mode,
playback path 7120 in L/R mode, and a playback path 7130 in depth mode for the
data block groups shown in FIG. 71 A.
FIG. 72A is a schematic diagram showing a fourth example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101 according to embodiment 1 of the present invention, and FIG.
72B is a schematic diagram showing a playback path 7210 in 2D playback mode,
playback path 7220 in L/R mode, and a playback path 7230 in depth mode for the
data block groups shown in FIG. 72A.
FIGS. 73A and 73B are graphs showing changes in the data amounts DA1
and DA2 stored in the read buffers 4021 and 4022 during a read period of data
blocks in accordance with the playback path 7220 in L/R mode shown in FIG. 72B.
FIG. 74 is a schematic diagram showing a third 3D extent block 7401 that
can be connected seamlessly to the first 3D extent block 7201 shown in FIG. 72A,
the file 2D #2 7410 and the file SS #2 7420 that share the base-view data blocks
therein, and playlist files 221, 222, 7430, and 7440 that define playback paths for
each of the files 241,244A, 7410, and 7420.
FIG. 75A is a schematic diagram showing a fifth example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101 according to embodiment 1 of the present invention, and FIG.
75B is a schematic diagram showing a playback path 7510 in 2D playback mode,
playback path 7520 in L/R mode, and a playback path 7530 in depth mode for the
data block groups shown in FIG. 75A.
FIGS. 76A and 76B are graphs showing changes in the data amounts DA1
and DA2 stored in the read buffers 4021 and 4022 during a read period of data
blocks in accordance with the playback path 7520 in L/R mode shown in FIG. 75B.
FIG. 77A is a schematic diagram showing a sixth example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101 according to embodiment 1 of the present invention, and FIG.
77B is a schematic diagram showing a playback path 7710 in 2D playback mode,
playback path 7720 in L/R mode, and a playback path 7730 in depth mode for the
data block groups shown in FIG. 77A.
FIGS. 78A and 78B are graphs showing changes in the data amounts DA1
and DA2 stored in the read buffers 4021 and 4022 during a read period of data
blocks in accordance with the playback path 7720 in L/R mode shown in FIG. 77B.
FIG. 79 is a schematic diagram showing the interleaved arrangement of an
extent group 7901 used in calculation of the minimum extent size and showing
corresponding playback paths 7920 and 7930 in 3D playback mode.
FIG. 80A is a schematic diagram showing multiplexed stream data divided
in order from the top into data blocks EXT[0]-EXT[n-l] (n>l) having a minimum
extent ATC time minText, and FIG. 80B is a schematic diagram showing multiplexed
stream data when the extent ATC time for the data blocks EXT[0]-EXT[n-l] shown
in FIG. 80A is lengthened beyond the minimum extent ATC time minText.
FIG. 81A is a schematic diagram showing the relationships between (i) a 3D
extent block 8110 designed for the purpose of using method «I» during 3D
playback mode and (ii) a playback path 8120 in L/R mode, FIG. 8IB is a graph
showing changes in the stored data amount DA1 in the first read buffer 4021 when
the 3D extent block 8110 is read according to the playback path 8120 in L/R mode,
and FIG. 81C is a graph showing changes in the stored data amount DA2 in the
second read buffer 4022 when the stored data amount DA1 in the first read buffer
4021 exhibits the changes in FIG. 81B.
FIGS. 82A and 82B are graphs showing changes in the data amounts DA1
and DA2 stored in the read buffers 4021 and 4022 when a sequence of 3D extent
blocks that satisfy expressions 50-53 is read by the playback device 102 in L/R
mode.
FIG. 83A is a schematic diagram showing the relationships between (i) a 3D
extent block 8310 designed for the purpose of using method «I» or «H» during
2D playback mode and (ii) a playback path 8320 in 2D playback mode, FIG. 83B is
a graph showing changes in the stored data amount DA in the read buffer 3621 when
the 3D extent block 8310 is read according to the playback path 8320 in 2D
playback mode, and FIG. 83C is a graph showing changes in the stored data amount
DA in the read buffer 3621 when the entire 3D extent block 8310 shown in FIG.
83A is read.
FIG. 84A is a schematic diagram showing the case when a BD-J object file
is read during the period in which 3D video images are played back from a 3D
extent block 8401 in accordance with a playback path 8420 in L/R mode, and FIG.
84B is a schematic diagram showing the case when a BD-J object file is read while
2D video images are being played back from a 3D extent block 8401 in accordance
with a playback path 8410 in 2D playback mode.
FIG. 85A is a schematic diagram representing (k+1) source packets SP #0,
SP #1, SP #2, ..., SP #k to be included in one 3D extent, FIG. 85B is a schematic
diagram showing the source packets SP #0-SP #k along an ATC time axis in order
of ATS, and FIG. 85C is a schematic diagram showing NULL packets inserted into
the empty regions shown in FIG. 85B.
FIG. 86A is a schematic diagram showing a playback path for multiplexed
stream data supporting multi-angle, FIG. 86B is a schematic diagram showing a data
block 8601 recorded on a BD-ROM disc according to modification [U] of
embodiment 1 of the present invention and a corresponding playback path 8602 in
L/R mode, and FIG. 86C is a schematic diagram showing the 3D extent blocks
constituting pieces of stream data Ak, Bk, and Ck for different angles.
FIG. 87A is a schematic diagram showing a first 3D extent block 8701
supporting multi-angle and three types of corresponding playback paths 8710, 8720,
and 8730, FIG. 87B is a schematic diagram showing a second 3D extent block 8702
supporting multi-angle and three types of corresponding playback paths 8711, 8721,
and 8731, and FIG. 87C is a schematic diagram showing a third 3D extent block
8703 supporting multi-angle and three types of corresponding playback paths 8712,
8722, and 8732.
FIG. 88 is a block diagram showing the internal structure of a recording
device according to embodiment 2 of the present invention.
FIGS. 89A and 89B are schematic diagrams showing a left-video image
picture and a right-video image picture used in display of one scene in a 3D video
image in a recording device according to embodiment 2 of the present invention, and
FIG. 89C is a schematic diagram showing depth information calculated from these
pictures by a video encoder 8801.
FIG. 90 is a functional block diagram of the integrated circuit 3 according to
embodiment 3 of the present invention.
FIG. 91 is a functional block diagram showing a typical structure of the
stream processing unit 5 shown in FIG. 90.
FIG. 92 is a schematic diagram showing the surrounding configuration
when the switching unit 53 shown in FIG. 91 is a DMAC.
FIG. 93 is a functional block diagram showing a typical structure of the AV
output unit 8 shown in FIG. 90.
FIG. 94 is a schematic diagram showing details regarding data output by the
playback device 102, which includes the AV output unit 8 shown in FIG. 93.
FIGS. 95A and 95B are schematic diagrams showing examples of the
topology of a control bus and data bus in the integrated circuit 3 shown in FIG. 90.
FIG. 96 is a flowchart of playback processing by a playback device 102 that
uses the integrated circuit 3 shown in FIG. 90.
FIG. 97 is a flowchart showing details on steps S1-5 shown in FIG. 96.
FIGS. 98A, 98B, and 98C are schematic diagrams illustrating the principle
of playing back 3D video images according to a method using parallax video.
FIG. 99 is a schematic diagram showing an example of constructing a
left-view 9103L and a right-view 9103R from the combination of a 2D video image
9101 and a depth map 9102:
FIG. 100 is a schematic diagram showing technology to guarantee
compatibility of an optical disc on which 3D video content is recorded with a 2D
playback device.
[Description of Embodiments]
[0018] The following describes a recording medium and a playback device
pertaining to preferred embodiments of the present invention with reference to the
drawings.
[0019] «Embodiment 1»
[0020] FIG. 1 is a schematic diagram showing a home theater system using a
recording medium according to embodiment 1 of the present invention. This home
theater system adopts a 3D video image (stereoscopic video image) playback
method that uses parallax video images, and in particular adopts an alternate-frame
sequencing method as a display method (see for
details). As shown in FIG. 1, this home theater system plays back a recording
medium 101 and includes a playback device 102, a display device 103, shutter
glasses 104, and a remote control 105.
[0021] The recording medium 101 is a read-only Blu-ray disc (BD)™, i.e. a
BD-ROM disc. The recording medium 101 can be a different portable recording
medium, such as an optical disc with a different format such as DVD or the like, a
removable hard disk drive (HDD), or a semiconductor memory element such as an
SD memory card. This recording medium, i.e. the BD-ROM disc 101, stores a
movie content as 3D video images. This content includes video streams representing
a left-view and a right-view for the 3D video images. The content may further
include a video stream representing a depth map for the 3D video images. These
video streams are arranged on the BD-ROM disc 101 in units of data blocks and are
accessed using a file structure described below. The video streams representing the
left-view or the right-view are used by both a 2D playback device and a 3D playback
device to play the content back as 2D video images. Conversely, a pair of video
streams representing a left-view and a right-view, or a pair of video streams
representing either a left-view or a right-view and a depth map, are used by a 3D
playback device to play the content back as 3D video images.
[0022] A BD-ROM drive 121 is mounted on the playback device 102. The
BD-ROM drive 121 is an optical disc drive conforming to the BD-ROM format. The
playback device 102 uses the BD-ROM drive 121 to read content from the
BD-ROM disc 101. The playback device 102 further decodes the content into video
data/audio data. The playback device 102 is a 3D playback device and can play the
content back as both 2D video images and as 3D video images. Hereinafter, the
operational modes of the playback device 102 when playing back 2D video images
and 3D video images are respectively referred to as "2D playback mode" and "3D
playback mode". In 2D playback mode, video data only includes either a left-view
or a right-view video frame. In 3D playback mode, video data includes both
left-view and right-view video frames.
[0023] 3D playback mode is further divided into left/right (L/R) mode and depth
mode. In "L/R mode", a pair of left-view and right-view video frames is generated
from a combination of video streams representing the left-view and right-view. In
"depth mode", a pair of left-view and right-view video frames is generated from a
combination of video streams representing either a left-view or a right-view and a
depth map. The playback device 102 is provided with an L/R mode. The playback
device 102 may be further provided with a depth mode.
[0024] The playback device 102 is connected to the display device 103 via an HDMI
(High-Definition Multimedia Interface) cable 122. The playback device 102
converts the video data/audio data into a video signal/audio signal in the HDMI
format and transmits the signals to the display device 103 via the HDMI cable 122.
In 2D playback mode, only one of either the left-view or the right-view video frame
is multiplexed in the video signal. In 3D playback mode, both the left-view and the
right-view video frames are time-multiplexed in the video signal. Additionally, the
playback device 102 exchanges CEC messages with the display device 103 via the
HDMI cable 122. In this way, the playback device 102 can ask the display device
103 whether it supports playback of 3D video images.
[0025] The display device 103 is a liquid crystal display. Alternatively, the display
device 103 can be another type of flat panel display, such as a plasma display, an
organic EL display, etc., or a projector. The display device 103 displays video on the
screen 131 in accordance with a video signal, and causes the speakers to produce
audio in accordance with an audio signal. The display device 103 supports playback
of 3D video images. During playback of 2D video images, either the left-view or the
right-view is displayed on the screen 131. During playback of 3D video images, the
left-view and right-view are alternately displayed on the screen 131.
[0026] The display device 103 includes a left/right signal transmitting unit 132. The
left/right signal transmitting unit 132 transmits a left/right signal LR to the shutter
glasses 104 via infrared rays or by radio transmission. The left/right signal LR
indicates whether the image currently displayed on the screen 131 is a left-view or a
right-view image. During playback of 3D video images, the display device 103
detects switching of frames by distinguishing between a left-view frame and a
right-view frame from a control signal that accompanies a video signal. Furthermore,
the display device 103 switches the left/right signal LR synchronously with the
detected switching of frames.
[0027] The shutter glasses 104 include two liquid crystal display panels 141L and
141R and a left/right signal receiving unit 142. Each of the liquid crystal display
panels 141L and 141R constitute each of the left and right lens parts. The left/right
signal receiving unit 142 receives a left/right signal LR, and in accordance with
changes therein, transmits the signal to the left and right liquid crystal display panels
141L and 141R. In accordance with the signal, each of the liquid crystal display
panels 141L and 141R either lets light pass through the entire panel or shuts light
out. For example, when the left/right signal LR indicates a left-view display, the
liquid crystal display panel 141L for the left eye lets light pass through, while the
liquid crystal display panel 141R for the right eye shuts light out. When the left/right
signal LR indicates a right-view display, the display panels act oppositely. In this
way, the two liquid crystal display panels 141L and 141R alternately let light pass
through in sync with the switching of frames. As a result, when a viewer looks at the
screen 131 while wearing the shutter glasses 104, the left-view is shown only to the
viewer's left eye, and the right-view is shown only to the right eye. At that time, the
viewer is made to perceive the difference between the images seen by each eye as
the binocular parallax for the same stereoscopic image, and thus the video image
appears to be stereoscopic.
[0028] The remote control 105 includes an operation unit and a transmitting unit.
The operation unit includes a plurality of buttons. The buttons correspond to each of
the functions of the playback device 102 and the display device 103, such as turning
the power on or off, starting or stopping playback of the BD-ROM disc 101, etc. The
operation unit detects when the user presses a button and conveys identification
information for the button to the transmitting unit as a signal. The transmitting unit
converts this signal into a signal IR and outputs it via infrared rays or radio
transmission to the playback device 102 or the display device 103. On the other
hand, the playback device 102 and display device 103 each receive this signal IR,
determine the button indicated by this signal IR, and execute the function associated
with the button. In this way, the user can remotely control the playback device 102
or the display device 103.
[0029]
[0030] FIG. 2 is a schematic diagram showing the data structure of the BD-ROM
disc 101. As shown in FIG. 2, a BCA (Burst Cutting Area) 201 is provided at the
innermost part of the data recording area on the BD-ROM disc 101. Only the
BD-ROM drive 121 is permitted to access the BCA, and access by application
programs is prohibited. In this way, the BCA 201 can be used as technology for
copyright protection. In the data recording area outside of the BCA 201, tracks spiral
from the inner to the outer circumference. In FIG. 2, the track 202 is schematically
extended in a transverse direction. The left side represents the inner circumferential
part of the disc 101, and the right side represents the outer circumferential part. As
shown in FIG. 2, track 202 contains a lead-in area 202A, a volume area 202B, and a
lead-out area 202C in order from the inner circumference. The lead-in area 202A is
provided immediately on the outside edge of the BCA 201. The lead-in area 202A
includes information necessary for the BD-ROM drive 121 to access the volume
area 202B, such as the size, the physical address, etc. of the data recorded in the
volume area 202B. The lead-out area 202C is provided on the outermost
circumferential part of the data recording area and indicates the end of the volume
area 202B. The volume area 202B includes application data such as video images,
audio, etc.
[0031] The volume area 202B is divided into small areas 202D called "sectors". The
sectors have a common size, for example 2048 bytes. Each sector 202D is
consecutively assigned a number in order from the top of the volume area 202B.
These consecutive numbers are called logical block numbers (LBN) and are used in
logical addresses on the BD-ROM disc 101. During reading of data from the
BD-ROM disc 101, data to be read is specified through designation of the LBN for
the destination sector. In this way, the volume area 202B can be accessed in units of
sectors. Furthermore, on the BD-ROM disc 101, logical addresses are substantially
the same as physical addresses. In particular, in an area where the LBNs are
consecutive, the physical addresses are also substantially consecutive. Accordingly,
the BD-ROM drive 121 can consecutively read data pieces having consecutive
LBNs without making the optical pickup perform a seek.
[0032] The data recorded in the volume area 202B is managed under a
predetermined file system. UDF (Universal Disc Format) is adopted as this file
system. Alternatively, the file system may be ISO9660. The data recorded on the
volume area 202B is represented in a directory/file format in accordance with the
file system (see the Supplementary Explanation> for details). In other words, the
data is accessible in units of directories or files.
[0033] «Directory/File Structure on the BD-ROM Disc»
[0034] FIG. 2 further shows the directory/file structure of the data stored in the
volume area 202B on a BD-ROM disc 101. As shown in FIG. 2, in this directory/file
structure, a BD movie (BDMV) directory 210 is located directly below a ROOT
directory 203. Below the BDMV directory 210 are an index file (index.bdmv) 211
and a movie object file (MovieObjectbdmv) 212.
[0035] The index file 211 contains information for managing as a whole the content
recorded on the BD-ROM disc 101. In particular, this information includes
information to make the playback device 102 recognize the content, as well as an
index table. The index table is a correspondence table between a title constituting the
content and a program to control the operation of the playback device 102. This
program is called an "object". Object types are a movie object and a BD-J (BD
Java™) object.
[0036] The movie object file 212 generally stores a plurality of movie objects. Each
movie object stores a sequence of navigation commands. A navigation command is
a control command causing the playback device 102 to execute playback processes
similarly to general DVD players. Types of navigation commands are, for example,
a read-out command to read out a playlist file corresponding to a title, a playback
command to play back stream data from an AV stream file indicated by a playlist
file, and a transition command to make a transition to another title. Navigation
commands are written in an interpreted language and are deciphered by an
interpreter, i.e. a job control program, included in the playback device to make the
control unit execute the desired job. A navigation command is composed of an
opcode and an operand. The opcode describes the type of operation that the
playback device is to execute, such as dividing, playing back, or calculating a title,
etc. The operand indicates identification information targeted by the operation such
as the title's number, etc. The control unit of the playback device 102 calls a movie
object in response, for example, to a user operation and executes navigation
commands included in the called movie object in the order of the sequence. Thus, in
a manner similar to general DVD players, the playback device 102 first makes the
display device 103 display a menu to allow the user to select a command. The
playback device 102 then executes playback start/stop of a title, switches to another
title, etc. in response to the selected command, thereby dynamically changing the
progress of video playback.
[0037] As shown in FIG. 2, the BDMV directory 210 further contains a playlist
(PLAYLIST) directory 220; a clip information (CLIPINF) directory 230; a stream
(STREAM) directory 240; a BD-J object (BDJO: BD Java Object) directory 250;
and a Java archive (JAR: Java Archive) directory 260.
[0038] Three types of AV stream files, (O1000.m2ts) 241, (02000.m2ts) 242, and
(03000.m2ts) 243, as well as a stereoscopic interleaved file (SSIF) directory 244 are
located directly under the STREAM directory 240. Two types of AV stream files,
(OlOOO.ssif) 244A and (02000.ssif) 244B are located directly under the SSIF
directory 244.
[0039] An "AV stream file" refers to a file, from among an actual video content
recorded on a BD-ROM disc 101, that complies with the file format determined by
the file system. Such an actual video content generally refers to stream data in which
different types of stream data representing video, audio, subtitles, etc., i.e.
elementary streams, have been multiplexed. This multiplexed stream data can be
broadly divided into a main transport stream (TS) and a sub-TS depending on the
type of the internal primary video stream. A "main TS" is multiplexed stream data
that includes a base-view video stream as a primary video stream. A "base-view
video stream" is a video stream that can be played back independently and that
represents 2D video images. Note that the base view is referred to as the "main
view". A "sub-TS" is multiplexed stream data that includes a dependent-view video
stream as a primary video stream. A "dependent-view video stream" is a video
stream that requires a base-view video stream for playback and represents 3D video
images by being combined with the base-view video stream. Note that the dependent
view is referred to as the "sub view". The types of dependent-view video streams are
a right-view video stream, left-view video stream, and depth map stream. When the
2D video images represented by a base-view video stream are used as the left-view
of 3D video images by a playback device in L/R mode, a "right-view video stream"
is used as the video stream representing the right-view of the 3D video images. The
reverse is true for a "left-view video stream". When the 2D video images
represented by a base-view video stream are used to project 3D video images on a
virtual 2D screen by a playback device in depth mode, a "depth map stream" is used
as the video stream representing a depth map for the 3D video images.
[0040] Depending on the type of internal multiplexed stream data, an AV stream file
can be divided into three types: file 2D, dependent file (hereinafter, abbreviated as
"file DEP"), and interleaved file (hereinafter, abbreviated as "file SS"). A "file 2D"
is an AV stream file for playback of 2D video in 2D playback mode and includes a
main TS. A "file DEP" is an AV stream file that includes a sub-TS. An "file SS" is
an AV stream file that includes a main TS and a sub-TS representing the same 3D
video images. In particular, a file SS shares its main TS with a certain file 2D and
shares its sub-TS with a certain file DEP. In other words, in the file system on the
BD-ROM disc 101, a main TS can be accessed by both a file SS and a file 2D, and a
sub TS can be accessed by both a file SS and a file DEP. This setup, whereby a
sequence of data recorded on the BD-ROM disc 101 is common to different files
and can be accessed by all of the files, is referred to as "file cross-link".
[0041] In the example shown in FIG. 2, the first AV stream file (01000.m2ts) 241 is
a file 2D, and the second AV stream file (02000.m2ts) 242 and third AV stream file
(03000.m2ts) 243 are both files DEP. In this way, files 2D and files DEP are located
directly below the STREAM directory 240. The first AV stream file, i.e. the
base-view video stream that includes the file 2D 241, represents a left-view of 3D
video images. The second AV stream file, i.e. the dependent-view video stream that
includes the first file DEP 242, is a right-view video stream. The third AV stream
file, i.e. the dependent-view video stream that includes the second file DEP 243, is a
depth map stream.
[0042] In the example shown in FIG. 2, the fourth AV stream file (OlOOO.ssif) 244A
and the fifth AV stream file (02000.ssif) 244B are both a file SS. In this way, files
SS are located directly below the SSIF directory 244. The fourth AV stream file, i.e.
the first file SS 244A, shares a main TS, and in particular a base-view video stream,
with the file 2D 241 and shares a sub-TS, in particular a right-view video stream,
with the first file DEP 242. The fifth AV stream file, i.e. the second file SS 244B,
shares a main TS, and in particular a base-view video stream, with the file 2D 241
and shares a sub-TS, in particular a depth map stream, with the second file DEP 243.
[0043] Three types of clip information files, (01000.clpi) 231, (02000.clpi) 232, and
(03000.clpi) 233 are located in the CLIPINF directory 230. A "clip information file"
is a file associated on a one-to-one basis with a file 2D and a file DEP and in
particular contains the entry map for each file. An "entry map" is a correspondence
table between the presentation time for each scene represented by a file 2D or a file
DEP and the address within each file at which the scene is recorded. Among the clip
information files, a clip information file associated with a file 2D is referred to as a
"2D clip information file", and a clip information file associated with a file DEP is
referred to as a "dependent-view clip information file". Furthermore, when a file
DEP includes a right-view video stream, the corresponding dependent-view clip
information file is referred to as a "right-view clip information file". When a file
DEP includes a depth map stream, the corresponding dependent-view clip
information file is referred to as a "depth map clip information file". In the example
shown in FIG. 2, the first clip information file (01000.clpi) 231 is a 2D clip
information file and is associated with the file 2D 241. The second clip information
file (02000.clpi) 232 is a right-view clip information file and is associated with the
first file DEP 242. The third clip information file (03000.clpi) 233 is a depth map
clip information file and is associated with the second file DEP 243.
[0044] Three types of playlist files, (00001.mpls) 221, (00002.mpls) 222, and
(00003.mpls) 223 are located in the PLAYLIST directory 220. A "playlist file" is a
file that specifies the playback path of an AV stream file, i.e. the part of an AV
stream file to decode, and the order of decoding. The types of playlist files are a 2D
playlist file and a 3D playlist file. A "2D playlist file" specifies the playback path of
a file 2D. A "3D playlist file" specifies, for a playback device in 2D playback mode,
the playback path of a file 2D, and for a playback device in 3D playback mode, the
playback path of a file SS. As shown in the example in FIG. 2, the first playlist file
(00001.mpls) 221 is a 2D playlist file and specifies the playback path of the file 2D
241. The second playlist file (00002 .mpls) 222 is a 3D playlist file that specifies, for
a playback device in 2D playback mode, the playback path of the file 2D 241, and
for a playback device in L/R mode, the playback path of the first file SS 244A. The
third playlist file (00003 .mpls) is a 3D playlist file that specifies, for a playback
device in 2D playback mode, the playback path of the file 2D 241, and for a
playback device in depth mode, the playback path of the second file SS 244B.
[0045] A BD-J object file (XXXXX.bdjo) 251 is located in the BDJO directory 250.
The BD-J object file 251 includes a single BD-J object. The BD-J object is a
bytecode program to cause a Java virtual machine mounted on the playback device
102 to execute the processes of title playback and graphics rendering. The BD-J
object is written in a compiler language such as Java or the like. The BD-J object
includes an application management table and identification information for the
playlist file to which is referred. The "application management table" is a list of the
Java application programs to be executed by the Java virtual machine and their
period of execution (lifecycle). The "identification information of the playlist file to
which is referred" identifies a playlist file that corresponds to a title to be played
back. The Java virtual machine calls a BD-J object in response to a user operation or
an application program, and executes the Java application program according to the
application management table included in the BD-J object. Consequently, the
playback device 102 dynamically changes the progress of the video for each title
played back, or causes the display device 103 to display graphics independently of
the title video.
[0046] A JAR file (YYYYY.jar) 261 is located in the JAR directory 260. The JAR
directory 261 generally includes a plurality of actual Java application programs to be
executed in accordance with the application management table shown in the BD-J
object. A Java application program is a bytecode program written in a compiler
language such as Java or the like, as is the BD-J object. Types of Java application
programs include programs causing the Java virtual machine to execute playback of
a title process and programs causing the Java virtual machine to execute graphics
rendering. The JAR file 261 is a Java archive file, and when it is read by the
playback device 102, it is extracted in internal memory. In this way, a Java
application program is stored in memory.
[0047] «Structure of Multiplexed Stream Data»
[0048] FIG. 3A is a list of elementary streams multiplexed in a main TS on a
BD-ROM disc 101. The main TS is a digital stream in MPEG-2 transport stream
(TS) format and includes the file 2D 241 shown in FIG. 2. As shown in FIG. 3A, the
main TS includes a primary video stream 301 and primary audio streams 302A and
302B. The main TS may additionally include presentation graphics (PG) streams
303A and 303B, an interactive graphics (IG) stream 304, a secondary audio stream
305, and a secondary video stream 306.
[0049] The primary video stream 301 represents the primary video of a movie, and
the secondary video stream 306 represents secondary video of the movie. The
primary video is the major video of a content, such as the main feature of a movie,
and is displayed on the entire screen, for example. On the other hand, the secondary
video is displayed simultaneously with the primary video with the use, for example,
of a picture-in-picture method, so that the secondary video images are displayed in a
smaller window presented on the full screen displaying the primary video image.
The primary video stream 301 and the secondary video stream 306 are both a
base-view video stream. Each of the video streams 301 and 306 is encoded by a
video compression encoding method, such as MPEG-2, MPEG-4 AVC, or SMPTE
VC-1.
[0050] The primary audio streams 302A and 302B represent the primary audio of
the movie. In this case, the two primary audio streams 302A and 302B are in
different languages. The secondary audio stream 305 represents secondary audio to
be mixed with the primary audio. Each of the audio streams 302A, 302B, and 305 is
encoded by a method such as AC-3, Dolby Digital Plus ("Dolby Digital" is a
registered trademark), Meridian Lossless Packing™ (MLP), Digital Theater
System™ (DTS), DTS-HD, or linear pulse code modulation (PCM).
[0051] Each of the PG streams 303A and 303B represent subtitles or the like via
graphics and are graphics video images to be displayed superimposed on the video
images represented by the primary video stream 301. The two PG streams 303A and
303B represent, for example, subtitles in a different language. The IG stream 304
represents graphical user interface (GUI) graphics components, and the arrangement
thereof, for constructing an interactive screen on the screen 131 in the display device
103.
[0052] The elementary streams 301-306 are identified by packet IDs (PIDs). PIDs
are assigned, for example, as follows. Since one main TS includes only one primary
video stream, the primary video stream 301 is assigned a hexadecimal value of
0x1011. When up to 32 other elementary streams can be multiplexed by type in one
main TS, the primary audio streams 302A and 302B are each assigned any value
from 0x1100 to 0x111F. The PG streams 303A and 303B are each assigned any
value from 0x1200 to 0x121F. The IG stream 304 is assigned any value from
0x1400 to 0x141F. The secondary audio stream 305 is assigned any value from
0x1A00 to 0x1A1F. The secondary video stream 306 is assigned any value from
0x1B100 to 0x1B1F.
[0053] FIG. 3B is a list of elementary streams multiplexed in the first sub-TS on a
BD-ROM disc 101. The first sub-TS is multiplexed stream data in MPEG-2 TS
format and is included in the first file DEP 242 shown in FIG. 2. As shown in FIG.
3B, the first sub-TS includes a primary video stream 311. The first sub-TS may
additionally include left-view PG streams 312A and 312B, right-view PG streams
313A and 313B, a left-view IG stream 314, right-view IG stream 315, and secondary
video stream 316. The primary video stream 311 is a right-view video stream, and
when the primary video stream 301 in the main TS represents the left-view for 3D
video images, the primary video stream 311 represents the right-view for the 3D
video images. When graphics video images for subtitles or the like are represented
as 3D video images, pairs formed by the left-view or right-view and a PG stream, i.e.
312A+313A and 312B+313B, represent the corresponding left-view and right-view.
When graphics video images for an interactive display are represented as 3D video
images, pairs formed by the left-view or right-view and the IG streams 314 and 315
represent the corresponding left-view and right-view. The secondary video stream
316 is a right-view video stream, and when the secondary video stream 306 in the
main TS represents the left-view for 3D video images, the secondary video stream
316 represents the right-view for the 3D video images.
[0054] PIDs are assigned to the elementary streams 311-316, for example, as
follows. The primary video stream 311 is assigned a value of 0x1012. When up to
32 other elementary streams can be multiplexed by type in one sub-TS, the left-view
PG streams 312A and 312B are assigned any value from 0x1220 to 0xl23F, and the
right-view PG streams 313A and 313B are assigned any value from 0x1240 to
0x125F. The left-view IG stream 314 is assigned any value from 0x1420 to 0x143F,
and the right-view IG stream 315 is assigned any value from 0x1440 to 0x145F. The
secondary video stream 316 is assigned any value from 0x1B20 to 0x1B3F.
[0055] FIG. 3C is a list of elementary streams multiplexed in the second sub-TS on a
BD-ROM disc 101. The second sub-TS is multiplexed stream data in MPEG-2 TS
format and is included in the second file DEP 243 shown in FIG. 2. As shown in
FIG. 3C, the second sub-TS includes a primary video stream 321. The second
sub-TS may additionally include depth map PG streams 323A and 323B, a depth
map IG stream 324, and secondary video stream 326. The primary video stream 321
is a depth map stream and represents 3D video images in combination with the
primary video stream 301 in the main TS. When the 2D video images represented by
the PG streams 323A and 323B in the main TS are used to project 3D video images
on a virtual 2D screen, the depth map PG streams 323A and 323B are used as the
PG streams representing a depth map for the 3D video images. When the 2D video
images represented by the IG stream 304 in the main TS are used to project 3D
video images on a virtual 2D screen, the depth map IG stream 324 is used as the IG
stream representing a depth map for the 3D video images. The secondary video
stream 326 is a depth map stream and represents 3D video images in combination
with the secondary video stream 306 in the main TS.
[0056] PIDs are assigned to the elementary streams 321-326, for example, as
follows. The primary video stream 321 is assigned a value of 0x1013. When up to
32 other elementary streams can be multiplexed by type in one sub-TS, the depth
map PG streams 323A and 323B are assigned any value from 0x1260 to 0x127F.
The depth map IG stream 324 is assigned any value from 0x1460 to 0x147F. The
secondary video stream 326 is assigned any value from 0x1B40 to 0x1B5F.
[0057] FIG. 4 is a schematic diagram showing the arrangement of TS packets in the
multiplexed stream data 400. The main TS and sub TS share this packet structure. In
the multiplexed stream data 400, the elementary streams 401, 402, 403, and 404 are
respectively converted into sequences of TS packets 421, 422, 423, and 424. For
example, in the video stream 401, each frame 401A or each field is first converted
into a packetized elementary stream (PES) packet 411. Next, each PES packet 411 is
generally converted into a plurality of TS packets 421. Similarly, the audio stream
402, PG stream 403, and IG stream 404 are each first converted into a sequence of
PES packets 412, 413, and 414, after which they are converted into TS packets 422,
423, and 424. Finally, the TS packets 421, 422, 423, and 424 obtained from the
elementary streams 401, 402, 403, and 404 are time-multiplexed into one piece of
stream data, i.e. the main TS 400.
[0058] FIG. 5B is a schematic diagram of a TS packet sequence constituting
multiplexed stream data. Each TS packet 501 is 188 bytes long. As shown in FIG.
5B, each TS packet 501 includes a TS header 501H and either, or both, a TS payload
501P and an adaptation field (hereinafter abbreviated as "AD field") 501A. The TS
payload 501P and AD field 501A together constitute a 184 byte long data area. The
TS payload 501P is used as a storage area for a PES packet. The PES packets
411-414 shown in FIG. 4 are typically divided into multiple parts, and each part is
stored in a different TS payload 501P. The AD field 501A is an area for storing
stuffing bytes (i.e. dummy data) when the amount of data in the TS payload 501P
does not reach 184 bytes. Additionally, when the TS packet 501 is, for example, a
program clock reference (PCR) as described below, the AD field 501A is used to
store such information. The TS header 501H is a four-byte long data area.
[0059] FIG. 5A is a schematic diagram showing the data structure of a TS header
501H. As shown in FIG. 5 A, the TS header 501H includes a TS degree of priority
(transport_priority) 511, PID 512, and AD field control (adaptation_field_control)
513. The PID 512 indicates the PID for the elementary stream whose data is stored
in the TS payload 501P of the TS packet 501 containing the PID 512. The TS degree
of priority 511 indicates the degree of priority of the TS packet 501 among the TS
packets that share the value indicated by the PID 512. The AD field control 513
indicates whether the TS packet 501 contains an AD field 501A and/or a TS payload
501P. For example, if the AD field control 513 indicates "1", then the TS packet 501
does not include an AD field 501A but includes a TS payload 501P. If the AD field
control 513 indicates "2", then the reverse is true. If the AD field control 513
indicates "3", then the TS packet 501 includes both an AD field 501A and a TS
payload 50IP.
[0060] FIG. 5C is a schematic diagram showing the formation of a source packet
sequence composed of the TS packet sequence for multiplexed stream data. As
shown in FIG. 5C, each source packet 502 is 192 bytes long and includes one TS
packet 501, shown in FIG. 5B, and a four-byte long header (TPExtraHeader)
502H. When the TS packet 501 is recorded on the BD-ROM disc 101, a source
packet 502 is constituted by attaching a header 502H to the TS packet 501. The
header 502H includes an ATS (Arrival_Time_Stamp). The "ATS" is time
information used as follows. When a source packet 502 is sent from the BD-ROM
disc 101 to a system target decoder in the playback device 102, the TS packet 502P
is extracted from the source packet 502 and transferred to a PID filter in the system
target decoder. The ATS in the header 502H indicates the time at which this transfer
is to begin. The "system target decoder" is a device that decodes multiplexed stream
data one elementary stream at a time. Details regarding the system target decoder
and its use of the ATS are provided below.
[0061] FIG. 5D is a schematic diagram of a sector group, in which a sequence of
source packets 502 are consecutively recorded, in the volume area 202B of the
BD-ROM disc 101. As shown in FIG. 5D, 32 source packets 502 are recorded at a
time as a sequence in three consecutive sectors 521, 522, and 523. This is because
the data amount for 32 source packets, i.e. 192 bytes x 32 = 6144 bytes, is the same
as the total size of three sectors, i.e. 2048 bytes x 3 = 6144 bytes. 32 source packets
502 that are recorded in this way in three consecutive sectors 521, 522, and 523 are
referred to as an "aligned unit" 520. The playback device 102 reads source packets
502 from the BD-ROM disc 101 by each aligned unit 520, i.e. 32 source packets at a
time. Also, the sector group 511,512, 513,...is divided into 32 pieces in order from
the top, and each forms one error correction code block 530. The BD-ROM drive
121 performs error correction processing for each ECC block 530.
[0062] «Data Structure of the Video Stream»
[0063] Each of the pictures included in the video stream represent one frame or one
field and are compressed by a video compression encoding method, such as
MPEG-2, MPEG-4 AVC, etc. This compression uses the picture's spatial or
temporal redundancy. Here, picture encoding that only uses the picture's spatial
redundancy is referred to as "intra-picrure encoding". On the other hand, picture
encoding that uses the similarity between data for multiple pictures displayed
sequentially is referred to as "inter-picture predictive encoding". In inter-picture
predictive encoding, first, a picture earlier or later in presentation time is assigned to
the picture to be encoded as a reference picture. Next, a motion vector is detected
between the picture to be encoded and the reference picture, and then motion
compensation is performed on the reference picture using the motion vector.
Furthermore, the difference value between the picture obtained by motion
compensation and the picture to be encoded is sought, and temporal redundancy is
removed using the difference value. In this way, the amount of data for each picture
is compressed.
[0064] FIG. 6 is a schematic diagram showing, in order of presentation time, three
pictures 601, 602, and 603 included in a video stream. As shown in FIG. 6, the
pictures 601, 602, and 603 are typically divided into a plurality of slices 611, ...,
621, 622, 623, ..., 631, .... A "slice" is a band-shaped region formed by
macroblocks that typically line up horizontally. A "macroblock" is a pixel matrix of
a predetermined size, such as 16 * 16. While not shown in FIG. 6, one slice may be
composed of two or more rows of macroblocks. In the above-mentioned encoding
method, pictures are compressed one slice at a time. After compression, a slice is
classified into one of three types: I slice, P slice, and B slice. An "I (Intra) slice" 621
refers to a slice compressed by intra-picture encoding. A "P (Predictive) slice" 622
refers to a slice compressed by inter-picture predictive encoding, having used as a
reference picture one picture 601 that has an earlier presentation time. A "B
(Bidirectionally Predictive) slice" 623 refers to a slice compressed by inter-picture
predictive encoding, having used two pictures 601, 603 that have an earlier or later
presentation time. In FIG. 6, the pictures to which a P slice 622 and a B slice 623
refer are indicated by arrows. In MPEG-4 AVC, as shown in FIG. 6, one picture 602
may include different types of slices. In MPEG-2, however, one picture only
includes slices of the same type.
[0065] For the sake of convenience, in the following explanation it is assumed that
one picture only includes slices of the same type, regardless of the encoding method.
In this case, after compression a picture is classified into one of three types, in
accordance with the type of the slice: I picture, P picture, and B picture. Furthermore,
B pictures that are used as a reference picture for other pictures in inter-picture
predictive encoding are particularly referred to as "Br (reference B) pictures".
[0066] FIG. 7 is a schematic diagram showing the pictures for a base-view video
stream 701 and a right-view video stream 702 in order of presentation time. As
shown in FIG. 7, the base-view video stream 701 includes pictures 710, 711, 712, ...,
719 (hereinafter "base-view pictures"), and the right-view video stream 702 includes
pictures 720, 721, 722, ..., 729 (hereinafter "right-view pictures"). Each of the
pictures 710-719 and 720-729 represents one frame or field and is compressed by a
video compression encoding method, such as MPEG-2, MPEG-4 AVC, etc.
[0067] As shown in FIG. 7, the base-view pictures 710-719 are typically divided
into a plurality of GOPs 731 and 732. A "GOP" refers to a sequence of pictures
having an I picture at the top of the sequence. The pictures in the GOPs 731 and 732
are compressed in the following order. In the first GOP 731, the top picture is
compressed as Iq picture 710. The subscripted number indicates the sequential
number allotted to each picture in the order of presentation time. Next, the fourth
picture is compressed as P3 picture 713 using I0 picture 710 as a reference picture.
The arrows shown in FIG. 7 indicate that the picture at the head of the arrow is a
reference picture for the picture at the tail of the arrow. Next, the second and third
pictures are respectively compressed as Br1 picture 711 and Br2 picture 712, using
both I0 picture 710 and P3 picture 713 as reference pictures. Furthermore, the
seventh picture is compressed as P6 picture 716 using P3 picture 713 as a reference
picture. Next, the fourth and fifth pictures are respectively compressed as Br4 picture
714 and Br5 picture 715, using both P3 picture 713 and P6 picture 716 as reference
pictures. Similarly, in the second GOP 732, the top picture is first compressed as I7
picture 717. Next, the third picture is compressed as P9 picture 719 using I7 picture
717 as a reference picture. Subsequently, the second picture is compressed as Brg
picture 718 using both I7 picture 717 and P9 picture 719 as reference pictures.
[0068] In the base-view video stream 701, each GOP 731 and 732 always contains
an I picture at the top, and thus pictures can be decoded GOP by GOP. For example,
in the first GOP 731, the I0 picture 710 is first decoded independently. Next, the P3
picture 713 is decoded using the decoded I0 picture 710. Then the Bri picture 711
and Br2 picture 712 are decoded using both the decoded I0 picture 710 and P3 picture
713. The subsequent picture group 714, 715, ... is similarly decoded. In this way,
the base-view video stream 701 can be decoded independently and furthermore can
be randomly accessed in units of GOPs.
[0069] As further shown in FIG. 7, the pictures 720-729 are compressed by
inter-picture encoding. However, the encoding method differs from the encoding
method for the pictures 710-719, since in addition to redundancy in the temporal
direction of video images, redundancy between the left and right video images is
also used. In particular, as shown by the arrows in FIG. 7, the base-view picture
having the same presentation time as each right-view picture is selected as a
reference picture for that right-view picture. These pictures represent a right-view
and a left-view for the same 3D video image, i.e. a parallax video image. On the
other hand, when the base-view picture is either an I picture or a P picture, a B
picture is not selected as a reference picture during compression of the
corresponding right-view picture.
[0070] Specifically, the top right-view picture is compressed as P0 picture 720 using
I0 picture 710 in the base-view video stream 701 as a reference picture. These
pictures 710 and 720 represent the left-view and right-view of the top frame in the
3D video images. Next, the fourth right-view picture is compressed as P3 picture 723
using P3 picture 713 in the base-view video stream 701 and P0 picture 720 as
reference pictures. In this case, the base-view picture corresponding to P3 picture
723 is P3 picture 713. Accordingly, during compression of P3 picture 723, a B
picture is not selected as a reference picture. For example, as shown by the cross in
FIG. 7, B1 picture 721 is prohibited from being selected as a reference picture. Next,
the second picture is compressed as B1 picture 721, using Br1 picture 711 in the
base-view video stream 701 in addition to P0 picture 720 and P3 picture 723 as
reference pictures. Similarly, the third picture is compressed as B2 picture 722, using
Br2 picture 712 in the base-view video stream 701 in addition to P0 picture 720 and
P3 picture 723 as reference pictures. Similarly, for subsequent pictures 724-729, the
pictures for which the presentation time is substantially equal are used as reference
pictures. In particular, since P6 picture 726, P7 picture 727, and P9 picture 729
respectively correspond to P6 picture 716, P7 picture 717, and P9 picture 719 in the
base-view video stream 701, a B picture is not selected as a reference picture during
compression of each of these pictures. For example, during compression of P6
picture 726, as shown by the cross in FIG. 7, B5 picture 725 is prohibited from being
selected as a reference picture.
[0071] The revised standards for MPEG-4 AVC/H.264, called multiview video
coding (MVC), are known as a video compression encoding method that makes use
of correlation between left and right video images as described previously. MVC
was created in July of 2008 by the joint video team (JVT), a joint project between
ISO/IEC MPEG and ITU-T VCEG, and is a standard for collectively encoding video
that can be seen from a plurality of perspectives. With MVC, not only is temporal
similarity in video images used for inter-video predictive encoding, but so is
similarity between video images from differing perspectives. This type of predictive
encoding has a higher video compression ratio than predictive encoding that
individually compresses data of video images seen from each perspective.
[0072] As described previously, right-view pictures 720-729 and base-view pictures
710-719 are in one-to-one correspondence in presentation order, and during
compression of a right-view picture, the corresponding base-view picture is used as
one of the reference pictures. Therefore, unlike the base-view video stream 701, the
right-view video stream 702 cannot be decoded independently. On the other hand,
however, the difference between parallax images is generally very small, that is, the
correlation between the left-view and the right-view is high. Accordingly, the
right-view pictures 720-729 generally have a significantly higher compression rate
than the base-view pictures 710-719, meaning that the amount of data is
significantly smaller.
[0073] Furthermore, when a base-view picture is either an I picture or a P picture,
the corresponding right-view picture is encoded without using a B picture as a
reference picture. As a result, when an I picture or P picture is selectively decoded
from the base-view video stream, a 3D video image can be played back as long as
the corresponding picture is decoded from the right-view video stream. Accordingly,
during trickplay of 3D video images, the burden on the 3D playback device of
decoding the video stream can be further reduced.
[0074] FIG. 8 is a schematic diagram showing the pictures in the base-view video
stream 701 and in the depth map stream 801 in order of presentation time. As shown
in FIG. 8, the base-view video stream 701 is the same as the one shown in FIG. 7.
Accordingly, a detailed description thereof can be found in the description of FIG. 7.
On the other hand, the depth map stream 801 includes depth maps 810, 811,812, ...,
819. The depth maps 810-819 are in one-to-one correspondence with the base-view
pictures 710-719 and represent a depth map for the 2D video image for one frame or
field shown by each picture.
[0075] The depth maps 810-819 are compressed by a video compression encoding
method, such as MPEG-2, MPEG-4 AVC, etc., in the same way as the base-view
pictures 710-719. In particular, inter-picture encoding is used in this encoding
method. In other words, each picture is compressed using another depth map as a
reference picture. Furthermore, when a base-view picture is either an I picture or a P
picture, a B picture is not selected as a reference picture during compression of the
depth map corresponding to the base-view picture.
[0076] As shown in FIG. 8, first the top of the depth map group corresponding to the
first GOP 731 is compressed as I0 picture 810. The subscripted number indicates the
sequential number allotted to each picture in the order of presentation time. Next,
the fourth depth map is compressed as P3 picture 813 using I0 picture 810 as a
reference picture. The arrows shown in FIG. 8 indicate that the picture at the head of
the arrow is a reference picture for the picture at the tail of the arrow. In this case,
the base-view picture corresponding to P3 picture 813 is P3 picture 713. Accordingly,
during compression of P3 picture 813, a B picture is not selected as a reference
picture. For example, as shown by the cross in FIG. 8, B1 picture 811 is prohibited
from being selected as a reference picture. Next, the second and third depth maps are
respectively compressed as B1 picture 811 and B2 picture 812, using both I0 picture
810 and P3 picture 813 as reference pictures. Furthermore, the seventh depth map is
compressed as P6 picture 816 using P3 picture 813 as a reference picture. In this case,
the base-view picture corresponding to P6 picture 816 is P6 picture 716. Accordingly,
during compression of P6 picture 816, a B picture is not selected as a reference
picture. For example, as shown by the cross in FIG. 8, B5 picture 815 is prohibited
from being selected as a reference picture. Next, the fourth and fifth depth maps are
respectively compressed as B4 picture 814 and B5 picture 815, using both P3 picture
813 and P6 picture 816 as reference pictures. Similarly, in the depth map group
corresponding to the second GOP 832, the top depth map is first compressed as I7
picture 817. Next, the third depth map is compressed as P9 picture 819 using I7
picture 817 as a reference picture. In this case, since I7 picture 817 and P9 picture
819 respectively correspond to I7 picture 717 and P9 picture 719 in the base-view
video stream 701, a B picture is not selected as a reference picture during
compression of either of these pictures. Subsequently, the second depth map is
compressed as B8 picture 818 using I7 picture 817 and P9 picture 819 as reference
pictures.
[0077] The depth map stream 801 is divided into units of GOPs in the same way as
the base-view video stream 701, and each GOP always contains an I picture at the
top. Accordingly, depth maps can be decoded GOP by GOP. For example, the Io
picture 810 is first decoded independently. Next, the P3 picture 813 is decoded using
the decoded I0 picture 810. Then, the Bj picture 811 and B2 picture 812 are decoded
using both the decoded I0 picture 810 and P3 picture 813. The subsequent picture
group 814, 815, ... is similarly decoded. However, since a depth map itself is only
information representing the depth of each part of a 2D video image pixel by pixel,
the depth map stream 801 cannot be used independently for playback of video
images.
[0078] Furthermore, when a base-view picture is either an I picture or a P picture,
the corresponding depth map is encoded without using a B picture as a reference
picture. As a result, when an I picture or P picture is selectively decoded from the
base-view video stream, a 3D video image can be played back as long as the
corresponding depth map is decoded from the depth map stream. Accordingly,
during trickplay of 3D video images, the burden on the 3D playback device of
decoding the video stream can be further reduced.
[0079] The same encoding method is used for compression of the right-view video
stream 702 and the depth map stream 801. For example, if the right-view video
stream 702 is encoded in MVC format, the depth map stream 801 is also encoded in
MVC format. In this case, during playback of 3D video images, the playback device
102 can smoothly switch between L/R mode and depth mode, while maintaining a
constant encoding method.
[0080] FIGS. 9 and 10 are schematic diagrams showing details on the data structure
of a video stream 900. As shown in FIGS. 9 and 10, the video stream 900 is
typically composed of a series of video sequences #1, #2, ..., #M (an integer M is
one or more). As shown in FIG. 9, a "video sequence" is a combination of pictures
911, 912, 913, 914, ... that constitute a single GOP 910 and to which additional
information, such as a header, has been individually attached. The combination of
this additional information and a picture is referred to as a "video access unit
(VAU)". That is, in each video sequence #1, #2, ..., #M, a single VAU is formed for
each picture. Each picture can be read from the video stream 900 in units of VAUs.
The base-view video stream and dependent-view video stream substantially share
this VAU structure.
[0081] As further shown in FIG. 9, the structure of the VAU #1 located at the top of
each video sequence differs between the base-view video stream and the
dependent-view video stream.
[0082] The VAU #1 931 includes an access unit (AU) identification code 931A,
sequence header 931B, picture header 931C, supplementary data 931D, and
compressed picture data 931E. The AU identification code 931A is a predetermined
code indicating the top of the VAU #1 931. The sequence header 931B, also called a
GOP header, includes an identification number for the video sequence #1 which
includes the VAU #1 931. The sequence header 931B further includes information
shared by the whole GOP 910, e.g. resolution, frame rate, aspect ratio, and bit rate.
The picture header 931C indicates its own identification number, the identification
number for the video sequence #1, and information necessary for decoding the
picture, such as the type of encoding method. The supplementary data 931D
includes additional information regarding matters other than the decoding of the
picture, for example closed caption text information, information on the GOP
structure, and time code information. In particular, the supplementary data 931D
includes decode switch information, described below. The compressed picture data
931E includes a base-view picture 911 at the top of a GOP 910, i.e. an I picture. A
header is provided in the compressed picture data 931E for each slice in the I picture
911. Hereinafter, this header is referred to as a "slice header". All of the slice
headers include the identification number of the picture header 931C. As shown by
the arrow on the dashed line in FIG. 9, by referring to a picture header 931C with
the same identification number, the information necessary to decode each slice can
be retrieved from the picture header 931C. Furthermore, it is clear that each slice
belongs to the video sequence #1 from the identification number of the video
sequence #1 shown by the picture header 931C. Also, as shown by the arrow on the
alternating long and short dashed line in FIG. 9, by referring to a sequence header
931B using the identification number for the video sequence #1, the resolution,
frame rate, aspect ratio, and bit rate for each slice can be retrieved from the sequence
header 931B. Additionally, the VAU #1 931 may include padding data 931F as
necessary. Padding data 931F is dummy data. By adjusting the size of this padding
data 931F in conjunction with the size of the compressed picture data 931E, the bit
rate of the VAU #1 931 can be maintained at a predetermined value.
[0083] The VAU #1 932 includes a sub-sequence header 932B, picture header 932C,
supplementary data 932D, and compressed picture data 932E. The sub-sequence
header 932B includes the identification number for the video sequence #1 which
includes the VAU #1 932. The sub-sequence header 932B further includes
information shared by the whole GOP 910, e.g. resolution, frame rate, aspect ratio,
and bit rate. In particular, these values are set to match the values set to the
corresponding GOP in the base-view video stream. In other words, these values
equal the values shown by the sequence header 931B in the VAU #1 931. The
picture header 932C indicates its own identification number, the identification
number for the video sequence #1, and information necessary for decoding the
picture, such as the type of encoding method. The supplementary data 932D
includes additional information regarding matters other than the decoding of the
picture, for example closed caption text information, information on the GOP
structure, and time code information. In particular, the supplementary data 932D
includes decode switch information, described below. The compressed picture data
932E includes a dependent-view picture 911 at the top of a GOP 910, i.e. a P picture
or an I picture. A slice header is provided in the compressed picture data 932E for
each slice in the dependent-view picture 911. All of the slice headers include the
identification number of the picture header 932C. As shown by arrow on the dashed
line in FIG. 9, by referring to the picture header 932C with the same identification
number, the information necessary to decode each slice can be retrieved from the
picture header 932C. Furthermore, it is clear that each slice belongs to the video
sequence #1 from the identification number of the video sequence #1 shown by the
picture header 932C. Also, as shown by arrow on the alternating long and short
dashed line in FIG. 9, by referring to a sequence header 932B using the
identification number for the video sequence #1, the resolution, frame rate, aspect
ratio, and bit rate for each slice can be retrieved from the sequence header 932B.
Additionally, the VAU #1 932 may include padding data 932F as necessary.
Padding data 932F is dummy data. By adjusting the size of this padding data 932F in
conjunction with the size of the compressed picture data 932E, the bit rate of the
VAU #1 932 can be maintained at a predetermined value.
[0084] As further shown in FIG. 10, the structures of the second and subsequent
VAU #N (N = 2, 3, ...) included in each video sequence differ between the
base-view video stream and dependent-view video stream.
[0085] The VAU #N 941 in the base-view video stream differs from the VAU #1
931 shown in FIG. 9 as follows. First, the VAU #N 941 does not include a sequence
header. In this case, the picture header 941C indicates the same identification
number for the video sequence as the value shown by the sequence header 941B in
VAU #1 located at the top of the video sequence #M that includes the VAU #N 941.
That is, the picture header 941C indicates the identification number for the video
sequence #M. Accordingly, as shown by the arrow on the alternating long and short
dashed line in FIG. 10, by referring to a sequence header 941B using the
identification number for the video sequence #M, the resolution, frame rate, aspect
ratio, and bit rate for each slice can be retrieved from the sequence header 941B. The
VAU #1 941 may further include a sequence end code 941G. The sequence end code
941G indicates that the VAU #N 941 is located at the end of the video sequence #M.
The sequence end code 941G may additionally indicate that the VAU #N 941 is
located at a boundary of a continuous playback area in the video stream 900 (see
modification [I] for details). The VAU #N 941 may also include a stream end code
941H in addition to the sequence end code 941G. The stream end code 941H
indicates the end of the video stream 900.
[0086] The VAU #N 942 in the dependent-view video stream differs from the VAU
#1 932 shown in FIG. 9 as follows. First, the VAU #N 942 does not include a
sequence header. In this case, the picture header 942C indicates the same
identification number for the video sequence as the value shown by the sequence
header 942B in VAU #1 located at the top of the video sequence #M that includes
the VAU #N 942. That is, the picture header 942C indicates the identification
number for the video sequence #M. Accordingly, as shown by the arrow on the
alternating long and short dashed line in FIG. 10, by referring to a sequence header
942B using the identification number for the video sequence #M, the resolution,
frame rate, aspect ratio, and bit rate for each slice can be retrieved from the sequence
header 942B. The VAU #1 942 may further include a sequence end code 942G. The
sequence end code 942G indicates that the VAU #N 942 is located at the end of the
video sequence #M. The sequence end code 942G may additionally indicate that the
VAU #N 942 is located at a boundary of a continuous playback area in the video
stream 900 (see modification [I] for details). The VAU #N 942 may also include a
stream end code 942H in addition to the sequence end code 942G. The stream end
code 942H indicates the end of the video stream 900.
[0087] The specific content of each component in a VAU differs according to the
encoding method of the video stream 900. For example, when the encoding method
is MPEG-4 AVC, the components in the VAUs shown in FIGS. 9 and 10 are
composed of a single network abstraction layer (NAL) unit. Specifically, the AU
identification code 931 A, sequence header 931B, picture header 931C,
supplementary data 931D, compression picture data 931E, padding data 931F,
sequence end code 941G, and stream end code 941H respectively correspond to an
access unit delimiter (AU delimiter), sequence parameter set (SPS), picture
parameter set (PPS), supplemental enhancement information (SEI), slice data, filler
data, end of sequence, and end of stream.
[0088] FIG. 11 is a schematic diagram showing details on the method for storing the
video stream 1101 into a PES packet sequence 1102. The video stream 1101 may be
either a base-view video stream or a dependent-view video stream. As shown in FIG.
11, in the actual video stream 1101, pictures are multiplexed in the order of
encoding, not in the order of presentation time. In other words, as shown in FIG. 11,
in each VAU comprising the video stream 1101, Io picture 1110, P3 picture 1111, B1
picture 1112, B2 picture 1113, ... are stored in order from the top. The subscripted
number indicates the sequential number allotted to each picture in the order of
presentation time. I0 picture 1110 is used as a reference picture for encoding P3
picture 1111, and both I0 picture 1110 and P3 picture 1111 are used as reference
pictures for encoding B1 picture 1112 and B2 picture 1113. Each of these VAUs is
stored as a different PES packet 1120, 1121, 1122, 1123, ..., and each PES packet
1120, ... includes a PES payload 1120P and a PES header 1120H. VAUs are stored
in a PES payload 1120P. PES headers 1120H include a presentation time,
(presentation time-stamp, or PTS), and a decoding time (decoding time-stamp, or
DTS), for the picture stored in the PES payload 1120P in the same PES packet 1120.
[0089] As with the video stream 1101 shown in FIG. 11, the other elementary
streams shown in FIGS. 3 and 4 are stored in PES payloads in a sequence of PES
packets. Furthermore, the PES header in each PES packet includes the PTS for the
data stored in the PES payload for the PES packet.
[0090] FIGS. 12A and 12B are schematic diagrams showing the relationship
between the PTS and DTS assigned to each picture in the base-view video stream
1201 and in the dependent-view video stream 1202. As shown in FIG. 12, between
the video streams 1201 and 1202, the same PTSs and DTSs are assigned to a pair of
pictures representing the same frame or field in a 3D video image. For example, the
top frame or field in the 3D video image is rendered from a combination of I1 picture
1211 in the base-view video stream 1201 and P1 picture 1221 in the dependent-view
video stream 1202. Accordingly, the PTS and DTS for these two pictures 1211 and
1221 are the same. The subscripted numbers indicate the sequential number allotted
to each picture in the order of DTSs. Also, when the dependent-view video stream
1202 is a depth map stream, P1 picture 1221 is replaced by an I picture representing
a depth map for the I1 picture 1211. Similarly, the PTS and DTS for the pair of
second pictures in the video streams 1201 and 1202, i.e. P2 pictures 1212 and 1222,
are the same. The PTS and DTS are both the same for the pair of third pictures in the
video streams 1201 and 1202, i.e. Br3 picture 1213 and B3 picture 1223. The same is
also true for the pair Br4 picture 1214 and B4 picture 1224.
[0091] A pair of VAUs that include pictures for which the PTS and DTS are the
same between the base-view video stream 1201 and the dependent-view video
stream 1202 is called a "3D VAU". A "3D VAU" may simply be referred to as an
"access unit", and the above-described VAU may be referred to as a "view
component". Using the allocation of PTSs and DTSs shown in FIG. 12, it is easy to
cause the decoder in the playback device 102 in 3D mode to process the base-view
video stream 1201 and the dependent-view video stream 1202 in parallel in units of
3D VAUs. In this way, the decoder definitely processes a pair of pictures
representing the same frame or field in a 3D video image in parallel. Furthermore,
the sequence header in the 3D VAU at the top of each GOP includes the same
resolution, the same frame rate, and the same aspect ratio. In particular, this frame
rate is equal to the value when the base-view video stream 1201 is decoded
independently in 2D playback mode.
[0092] FIG. 13 is a schematic diagram showing the data structure of supplementary
data 931D shown in FIG. 9. Supplementary data 931D corresponds to a type of NAL
unit, "SEP, in particular in MPEG-4 AVC. As shown in FIG. 13, supplementary
data 931D includes decoding switch information 1301. The decoding switch
information 1301 is included in each VAU in both the base-view video stream and
the dependent-view video stream. The decoding switch information 1301 is
information to cause the decoder in the playback device 102 to easily specify the
next VAU to decode. As described below, the decoder alternately decodes the
base-view video stream and the dependent-view video stream in units of VAUs. At
that time, the decoder generally specifies the next VAU to be decoded in alignment
with the time shown by the DTS assigned to each VAU. Many types of decoders,
however, continue to decode VAUs in order, ignoring the DTS. For such decoders,
it is preferable for each VAU to include decoding switch information 1301 in
addition to a DTS.
[0093] As shown in FIG. 13, decoding switch information 1301 includes a
subsequent access unit type 1311, subsequent access unit size 1312, and decoding
counter 1313. The subsequent access unit type 1311 indicates whether the next VAU
to be decoded belongs to a base-view video stream or a dependent-view video
stream. For example, when the value of the subsequent access unit type 1311 is "1",
the next VAU to be decoded belongs to a base-view video stream, and when the
value of the subsequent access unit type 1311 is "2", the next VAU to be decoded
belongs to a dependent-view video stream. When the value of the subsequent access
unit type 1311 is "0", the current VAU is located at the end of the stream targeted
for decoding, and the next VAU to be decoded does not exist. The subsequent access
unit size 1312 indicates the size of the next VAU that is to be decoded. By referring
to the subsequent access unit size 1312, the decoder in the playback device 102 can
specify the size of a VAU without analyzing its actual structure. Accordingly, the
decoder can easily extract VAUs from the buffer. The decode counter 1313 shows
the decoding order of the VAU to which it belongs. The order is counted from a
VAU that includes an I picture in the base-view video stream.
[0094] FIG. 14A is a schematic diagram showing an example of decoding counters,
1410 and 1420, assigned to each picture in the base-view video stream 1401 and in
the dependent-view video stream 1402. As shown in FIG. 14A, the decode counters
1410 and 1420 are incremented alternately between the two video streams 1401 and
1402. For example, for VAU 1411 that includes an I picture in the base-view video
stream 1401, a value of "1" is assigned to the decode counter 1410. Next, a value of
"2" is assigned to the decode counter 1420 for the VAU 1421 that includes the next
P picture to be decoded in the dependent-view video stream 1402. Furthermore, a
value of "3" is assigned to the decode counter 1410 for the VAU 1412 that includes
the next P picture to be decoded in the base-view video stream 1401. By assigning
values in this way, even when the decoder in the playback device 102 fails to read
one of the VAUs due to some error, the decoder can immediately specify the
missing picture using the decode counters 1410 and 1420. Accordingly, the decoder
can perform error processing appropriately and promptly.
[0095] In the example shown in FIG. 14A, an error occurs during the reading of the
third VAU 1413 in the base-view video stream 1401, and the Br picture is missing.
During decoding processing of the P picture contained in the second VAU 1422 in
the dependent-view video stream 1402, however, the decoder has read the decode
counter 1420 for this VAU 1422 and retained the value. Accordingly, the decoder
can predict the decode counter 1410 for the next VAU to be processed. Specifically,
the decode counter 1420 in the VAU 1422 that includes the P picture is "4".
Therefore, the decode counter 1410 for the next VAU to be read can be predicted to
be "5". The next VAU that is actually read, however, is the fourth VAU 1414 in the
base-view video stream 1401, whose decode counter 1410 is "7". The decoder thus
detects that it failed to read a VAU. Accordingly, the decoder can execute the
following processing: "skip decoding processing of the B picture extracted from the
third VAU 1423 in the dependent-view video stream 1402, since the Br picture to be
used as a reference is missing". In this way, the decoder checks the decode counters
1410 and 1420 during each decoding process. Consequently, the decoder can
promptly detect errors during reading of VAUs and can promptly execute
appropriate error processing. As a result, the decoder can prevent noise from
contaminating the playback video.
[0096] FIG. 14B is a schematic diagram showing another example of decoding
counters, 1430 and 1440, assigned to each picture in the base-view video stream
1401 and in the dependent-view video stream 1402. As shown in FIG. 14B, decode
counters 1430 and 1440 are incremented separately in the video streams 1401 and
1402. Therefore, the decode counters 1430 and 1440 are the same for a pair of
pictures in the same 3D VAU. In this case, when the decoder has decoded a VAU in
the base-view video stream 1401, it can predict that "the decode counter 1430 is the
same as the decode counter 1440 for the next VAU to be decoded in the
dependent-view video stream 1402". Conversely, when the decoder has decoded a
VAU in the dependent-view video stream 1402, it can predict that "the decode
counter 1430 for the next VAU to be decoded in the base-view video stream 1401 is
the same as the decode counter 1440 plus one". Accordingly, at any point in time,
the decoder can promptly detect an error in reading a VAU using the decode
counters 1430 and 1440 and can promptly execute appropriate error processing. As a
result, the decoder can prevent noise from contaminating the playback video.
[0097] «Interleaved Arrangement of Multiplexed Stream Data»
[0098] For seamless playback of 3D video images, the physical arrangement of the
base-view video stream and dependent-view video stream on the BD-ROM disc 101
is important. This "seamless playback" refers to playing back video and audio from
multiplexed stream data without interruption.
[0099] FIG. 15 is a schematic diagram showing the physical arrangement on the
BD-ROM disc 101 of a data block group belonging to the main TS, first sub-TS, and
second sub-TS respectively shown in FIGS. 3A, 3B, and 3C. A "data block" refers
to a sequence of data recorded on a contiguous area on the BD-ROM disc 101, i.e. a
plurality of physically contiguous sectors. Since physical addresses and logical
addresses on the BD-ROM disc 101 are substantially the same, the LBNs within
each data block are also continuous. Accordingly, the BD-ROM drive 121 can
continuously read a data block without causing the optical pickup to perform a seek.
Hereinafter, data blocks L0, L1, L2, ... belonging to a main TS are referred to as
"base-view data blocks", and data blocks R0, R1, R2, ..., D0, D1, D2, ... belonging
to a sub-TS are referred to as "dependent-view data blocks". In particular, the data
blocks R0, R1, R2, ... belonging to the first sub-TS are referred to as "right-view
data blocks", and the data blocks D0, D1, D2, ... belonging to the second sub-TS are
referred to as "depth map data blocks". As shown in FIG. 15, a data block group is
recorded continuously along track 1501 on the BD-ROM disc 101. Furthermore, the
base-view data blocks L0, L1, L2, ..., right-view data blocks R0, R1, R2, ..., and
depth map data blocks DO, D1, D2, ... are arranged alternately one by one. This type
of arrangement of data blocks is referred to as an "interleaved arrangement".
[0100] In the interleaved arrangement according to embodiment 1 of the present
invention, the extent ATC time is the same between the three types of contiguous
data blocks. For example, in FIG. 15, the top depth map data block DO, top
right-view data block R0, and top base-view data block L0 are contiguous. The
extent ATC time is the same between these data blocks D0, R0, and L0. In this
context, an "Arrival Time Clock (ATC)" refers to a clock that acts as a standard for
an ATS. Also, the "extent ATC time" is defined by the value of the ATC and
represents the range of the ATS assigned to source packets in an extent, i.e. the time
interval from the ATS of the source packet at the top of the extent to the ATS of the
source packet at the top of the next extent. In other words, the extent ATC time is
the same as the time required to transfer all of the source packets in the extent from
the read buffer in the playback device 102 to the system target decoder. Note that the
"read buffer" is a buffer memory in the playback device 102 where data blocks read
from the BD-ROM disc 101 are temporarily stored before being transmitted to the
system target decoder. Details on the read buffer are provided below.
[0101] Furthermore, in the interleaved arrangement according to embodiment 1 of
the present invention, the three contiguous data blocks with the same extent ATC
time are arranged in the order of the depth map block, right-view data block, and
base-view data block, that is, starting with the smallest amount of data. For example,
in FIG. 15, the picture included in the top right-view data block R0 is compressed
using the picture included in the top base-view data block L0 as a reference picture,
as shown in FIG. 7. Accordingly, the size Sext2[0] of the top right-view data block R0
is equal to or less than the size Sextl[0] of the top base-view data block L0:
Sext2[0] for details).
[0113] In the examples shown in FIGS. 2 and 15, the file entry 1510 in the file 2D
(01000.m2ts) 241 indicates the sizes of the base-view data blocks L0, L1, L2, ... and
the LBNs of their tops. Accordingly, the base-view data blocks L0, L1, L2, ... can
be accessed as extents EXT2D[0], EXT2D[1], EXT2D[2], ... in the file 2D 241.
Hereinafter, the extents EXT2D[0], EXT2D[1], EXT2D[2], ... belonging to the file
2D 241 are referred to as "2D extents".
[0114] The file entry 1520 in the first file DEP (02000.m2ts) indicates the sizes of
the right-view data blocks R0, R1, R2, ... and the LBNs of their tops. Accordingly,
the right-view data blocks R0, R1, R2, ... can be accessed as extents EXT2[0],
EXT2[1], EXT2[2], ... in the first file DEP 242. Hereinafter, the extents EXT2[0],
EXT2[1], EXT2[2], ... belonging to the first file DEP 242 are referred to as
"right-view extents".
[0115] The file entry 1530 in the second file DEP (02000.m2ts) indicates the sizes
of the depth map data blocks DO, D1, D2, ... and the LBNs of their tops.
Accordingly, the depth map data blocks D1, D2, D3, ... can be accessed as extents
EXT3[0], EXT3[1], EXT3[2], ... in the second file DEP 243. Hereinafter, the
extents EXT3[0], EXT3[1], EXT3[2], ... belonging to the second file DEP 243 are
referred to as "depth map extents". Furthermore, extents that belong to any file DEP,
as do right-view extents and depth map extents, are collectively referred to as
"dependent-view extents".
[0116] For the data block group shown in FIG. 15, the AV stream files are
cross-linked as follows.
[0117] The file entry 1540 in the first file SS (01000.ssif) 244A considers pairs of
adjacent right-view data blocks and base-view data blocks R0+L0, R1+L1, R2+L2,
... to each be one extent, indicating the size of each and the LBN of the top thereof.
Accordingly, the pairs of data blocks R0+L0, R1+L1, R2+L2, ... can be accessed as
extents EXTSS[0], EXTSS[1], EXTSS[2], ... in the first file SS 244A. Hereinafter,
the extents EXTSS[0], EXTSS[1], EXTSS[2], ... belonging to the first file SS 244A
are referred to as "3D extents". The 3D extents EXTSS[n] (n = 0, 1, 2, ...) have
base-view data blocks Ln in common with the file 2D 241 and right-view data
blocks Rn in common with the first file DEP 242.
[0118] The file entry 1550 alternately indicates the size of depth map data blocks D0,
D1, D2, ... and base-view data blocks L0, L1, L2, ... and the LBNs of their tops.
Accordingly, the data blocks D1, L1, D2, L2, ... can be accessed as extents
EXTSS[0], EXTSS[1], EXTSS[2], EXTSS[3], ... in the second file SS 244B. The
extents in the second file SS 244B have base-view data blocks Ln in common with
the file 2D 241 and depth map data blocks Dn in common with the second file DEP
243.
[0119] «Playback Path for a Data Block Group in an Interleaved Arrangement»
[0120] FIG. 18 is a schematic diagram showing a playback path 1801 in 2D
playback mode, playback path 1802 in L/R mode, and playback path 1803 in depth
mode for the data block groups shown in FIG. 15.
[0121] In 2D playback mode, the playback device 102 plays back the file 2D 241.
Accordingly, as the playback path 1801 for 2D playback mode shows, the base-view
data blocks L0, L1, and L2 are read in order as 2D extents EXT2D[0], EXT2D[1],
and EXT2D[2]. That is, the top base-view data block L0 is first read, then reading of
the immediately subsequent depth map data block D1 and right-view data block R1
is skipped by a first jump J2D1. Next, the second base-view data block L1 is read,
and then reading of the immediately subsequent depth map data block D2 and
right-view data block R2 is skipped by a second jump J2d2. Subsequently, the third
base-view data block L2 is read.
[0122] In L/R mode, the playback device 102 plays back the first file SS 244A.
Accordingly, as the playback path 1802 for L/R playback mode shows, pairs of
adjacent right-view data blocks and base-view data blocks R0+L0, R1+L1, and
R2+L2 are read in order as 3D extents EXTSS[0], EXTSS[1], and EXTSS[2]. That
is, the top right-view data block R0 and the immediately subsequent base-view data
block L0 are first continuously read, then reading of the immediately subsequent
depth map data block D1 is skipped by a first jump Jlr1. Next, the second right-view
data block Rl and the immediately subsequent base-view data block L1 are
continuously read, and then reading of the immediately subsequent depth map data
block D2 is skipped by a second jump Jlr2. Subsequently, the third right-view data
block R2 and base-view data block L2 are continuously read.
[0123] In depth mode, the playback device 102 plays back the second file SS 244B.
Accordingly, as the playback path 1803 for depth mode shows, depth map data
blocks DO, D1, ... and base-view data blocks L0, L1, ... are alternately read as
extents EXTSS[0], EXTSS[1], EXTSS[2], EXTSS[3], ... in the second file SS 244B.
That is, the top depth map data block DO is first read, then reading of the
immediately subsequent right-view data block R0 is skipped by a first jump JLD1.
Next, the top base-view data block L0 and the immediately subsequent depth map
extent D1 are continuously read. Furthermore, reading of the immediately
subsequent right-view extent Rl is skipped by a second jump JLD2, and the second
base-view data block L1 is read.
[0124] As shown by the playback paths 1801-1803 in FIG. 18, in the area in which a
data block group is recorded in an interleaved arrangement, the playback device 102
can substantially read the data block groups in order from the top. In this case,
jumps occur during read processing. The distance of the jumps, however, differs
from the jumps shown in FIG. 16A and is sufficiently shorter than the entire length
of either the main TS or the sub-TS. Furthermore, for each pair of a base-view data
block and dependent-view data block with the same extent ATC time, the
dependent-view data block, which is comparatively small in size, is read first.
Therefore, the read buffer capacity of the playback device 102 can be reduced more
than if the data blocks were read in opposite order.
[0125] In L/R mode, the playback device 102 reads a data block group as an extent
group in the first file SS 244A. That is, the playback device 102 reads the LBN of
the top of each 3D extents EXTSS[0], EXTSS[1], ..., as well as the size thereof,
from the file entry 1540 in the first file SS 244A and then outputs the LBNs and
sizes to the BD-ROM drive 121. The BD-ROM drive 121 continuously reads data
having the input size from the input LBN. In such processing, control of the
BD-ROM drive 121 is easier than processing to read the data block groups as the
extents in the first file DEP 242 and the file 2D 241 for the following reasons (A)
and (B): (A) the playback device 102 can refer in order to extents using a file entry
in one location, and (B) since the total number of extents to be read substantially
halves, the total number of pairs of an LBN and a size that need to be output to the
BD-ROM drive 121 halves. Advantage (A) is also true for processing to read the
data block group as extents in the second file SS 244B in depth mode. However,
after the playback device 102 has read the 3D extents EXTSS[0], EXTSS[1], ..., it
needs to separate each into a right-view data block and a base-view data block and
output them to the decoder. The clip information file is used for this separation
processing. Details are provided below.
[0126] «Other TS Packets Included in the AV Stream File»
[0127] The types of the TS packets contained in the AV stream file include not only
those that are converted from the elementary streams shown in FIGS. 3A, 3B, and
3C, but also a program association table (PAT), program map table (PMT), and
program clock reference (PCR). The PCR, PMT, and PAT are specified by the
European Digital Broadcasting Standard and are intended to regulate the partial
transport stream constituting a single program. By using PCR, PMT, and PAT, the
AV stream file can also be regulated in the same way as the partial transport stream.
Specifically, the PAT shows the PID of a PMT included in the same AV stream file.
The PID of the PAT itself is 0. The PMT includes the PIDs for the elementary
streams representing video, audio, subtitles, etc. included in the same AV stream file,
as well as the attribute information for the elementary streams. The PMT also
includes various descriptors relating to the AV stream file. The descriptors
particularly include copy control information showing whether copying of the AV
stream file is permitted or not. The PCR includes information indicating the value of
a system time clock (STC) to be associated with the ATS assigned to the PCR itself.
The STC referred to here is a clock used as a reference for the PTS and the DTS by a
decoder in the playback device 102. This decoder uses the PCR to synchronize the
STC with the ATC.
[0128] FIG. 19 is a schematic diagram showing the data structure of a PMT 1910.
The PMT 1910 includes a PMT header 1901, descriptors 1902, and pieces of stream
information 1903. The PMT header 1901 indicates the length of data, etc. stored in
the PMT 1910. Each descriptor 1902 relates to the entire AV stream file that
includes the PMT 1910. The copy control information is included in one of the
descriptors 1902. Each piece of stream information 1903 relates to one of the
elementary streams included in the AV stream file and is assigned to a different
elementary stream. Each piece of stream information 1903 includes a stream type
1931, a PID 1932, and stream descriptors 1933. The stream type 1931 includes
identification information for the codec used for compressing the elementary stream.
The PID 1932 indicates the PID of the elementary stream. The stream descriptors
1933 include attribute information of the elementary stream, such as a frame rate
and an aspect ratio.
[0129] By using PCR, PMT, and PAT, the decoder in the playback device 102 can
be made to process the AV stream file in the same way as the partial transport
stream in the European Digital Broadcasting Standard. In this way, it is possible to
ensure compatibility between a playback device for the BD-ROM disc 101 and a
terminal device conforming to the European Digital Broadcasting Standard.
[0130] «Clip Information File»
[0131] FIG. 20 is a schematic diagram showing the data structure of the first clip
information file (01000.clpi), i.e. the 2D clip information file 231. The
dependent-view clip information files (02000.clip, 03000.clpi) 232 and 233 have the
same data structure. Below, the data structure common to all clip information files is
first described, using the data structure of the 2D clip information file 231 as an
example. Afterwards, the differences in data structure between a 2D clip information
file and a dependent-view clip information file are described.
[0132] As shown in FIG. 20, the 2D clip information file 231 includes clip
information 2010, stream attribute information 2020, an entry map 2030, and 3D
meta data 2040. The 3D meta data 2040 includes an offset table 2041 and an extent
start point 2042.
[0133] As shown in FIG. 20, the clip information 2010 includes a system rate 2011,
a playback start time 2012, and a playback end time 2013. The system rate 2011
indicates the maximum value of the transfer speed at which "TS packets" belonging
to the file 2D (01000.m2ts) 241 are transferred from the read buffer in the playback
device 102 to the system target decoder. The interval between the ATSs of the
source packets in the file 2D 241 is set so that the transfer speed of the TS packets is
limited to the system rate or lower. The playback start time 2012 indicates the PTS
of the VAU located at the top of the file 2D 241, e.g. the PTS of the top video frame.
The playback end time 2012 indicates the value of the STC delayed a predetermined
time from the PTS of the VAU located at the end of the file 2D 241, e.g. the sum of
the PTS of the last video frame and the playback time of one frame.
[0134] As shown in FIG. 20, the stream attribute information 2020 is a
correspondence table between the PID 2021 for each elementary stream included in
the file 2D 241 with pieces of attribute information 2022. Each piece of attribute
information 2022 is different for a video stream, audio stream, PG stream, and IG
stream. For example, the attribute information corresponding to the PID 0x1011 for
the primary video stream includes a codec type used for the compression of the
video stream, as well as a resolution, aspect ratio, and frame rate for each picture
constituting the video stream. On the other hand, the attribute information
corresponding to the PID 0x1101 for the primary audio stream includes a codec type
used for compressing the audio stream, number of channels included in the audio
stream, language, and sampling frequency. The playback device 102 uses this
attribute information 2022 to initialize the decoder.
[0135] [Entry Map]
[0136] FIG. 21A is a schematic diagram showing the data structure of an entry map
2030. As shown in FIG. 21 A, the entry map 2030 includes tables 2100. There is the
same number of tables 2100 as there are video streams multiplexed in the main TS,
and tables are assigned one-by-one to each video stream. In FIG. 31 A, each table
2100 is distinguished by the PID of the video stream to which it is assigned. Each
table 2100 includes an entry map header 2101 and an entry point 2102. The entry
map header 2101 includes the PID corresponding to the table 2100 and the total
number of entry points 2102 included in the table 2100. The entry point 2102
associates a pair of a PTS 2103 and source packet number (SPN) 2104 with one of
individually differing entry points ID (EPJD) 2105. The PTS 2103 is equivalent to
the PTS for one of the I pictures included in the video stream for the PID indicated
by the entry map header 2101. The SPN 2104 is equivalent to the SPN for the top of
the source packet group stored in the corresponding I picture. An "SPN" refers to
the number assigned consecutively from the top to a source packet group belonging
to one AV stream file. The SPN is used as the address for each source packet in the
AV stream file. In the entry map 2030 in the 2D clip information file 231, the SPN
refers to the number assigned to the source packet group belonging to the file 2D
241, i.e. the source packet group constituting the main TS. Accordingly, the entry
point 2102 expresses the relationship between the PTS and the address, i.e. the SPN,
of each I picture included in the file 2D 241.
[0137] An entry point 2102 does not need to be set for all of the I pictures in the file
2D 241. However, when an I picture is located at the top of a GOP, and the TS
packet that includes the top of that I picture is located at the top of a 2D extent, an
entry point 2102 has to be set for that I picture.
[0138] FIG. 21B is a schematic diagram showing source packets in a source packet
group 2110 belonging to the file 2D 241 that are associated with each EPID 2105
by the entry map 2030. FIG. 21C is a schematic diagram showing the relationships
between the source packet group 2110 and the data block group Dn, Rn, Ln (n = 0, 1,
2, 3, ...) on a BD-ROM disc. When the playback device 102 plays back 2D video
images from the file 2D 241, it refers to the entry map 2030 to specify the SPN for
the source packet that includes a frame representing an arbitrary scene from the PTS
for that frame. Specifically, when for example a PTS = 360000 is indicated as the
PTS for a specific entry point for the position to start playback, the playback device
102 first retrieves the SPN = 3200 allocated to this PTS in the entry map 2030. Next,
the playback device 102 seeks the quotient SPN * 192 / 2048, i.e. the value of the
SPN multiplied by 192 bytes, the data amount per source packet, and divided by
2048 bytes, the data amount per sector. As can be understood from FIGS. 5B and 5C,
this value is the same as the total number of sectors recorded in the main TS prior to
the source packet to which the SPN is assigned. In the example shown in FIG. 21B,
this value is 3200 x 192 / 2048 = 300, and is equal to the total number of sectors on
which source packet groups 2111 are recorded from SPN 0 through 3199. Next, the
playback device 102 refers to the file entry in the file 2D 241 and specifies the LBN
of the (total number+1)th sector, counting from the top of the sector groups in which
2D extent groups are recorded. In the example shown in FIG. 21C, within the sector
groups in which the base-view data blocks L0, L1, L2, ... which can be accessed as
2D extents EXT2D[0], EXT2D[1], EXT2D[2], ... are recorded, the LBN of the 301st
sector counting from the top is specified. The playback device 102 indicates this
LBN to the BD-ROM drive 121. In this way, base-view data block groups are read
as aligned units in order from the sector for this LBN. Furthermore, from the first
aligned unit that is read in, the playback device 102 selects the source packet
indicated by the entry point for the position to start playback and decodes an I
picture. From then on, subsequent pictures are decoded in order referring to already
decoded pictures. In this way, the playback device 102 can play back 2D video
images from the file 2D 241 from a specified PTS onwards.
[0139] Furthermore, the entry map 2030 is useful for efficient processing during
trickplay such as fast forward, reverse, etc. For example, the playback device 102 in
2D playback mode first refers to the entry map 2030 to read SPNs starting at the
position to start playback, e.g. to read SPN = 3200, 4800, ... in order from the entry
points EP_ID = 2, 3, ... that include PTSs starting at PTS = 360000. Next, the
playback device 102 refers to the file entry in the file 2D 241 to specify the LBN of
the sectors corresponding to each SPN. The playback device 102 then indicates each
LBN to the BD-ROM drive 121. Aligned units are thus read from the sector for each
LBN. Furthermore, from each aligned unit, the playback device 102 selects the
source packet indicated by each entry point and decodes an I picture. The playback
device 102 can thus selectively play back an I picture from the file 2D 241 without
analyzing the 2D extent group EXT2D[n] itself.
[0140] [Offset Table]
[0141] FIG. 22A is a schematic diagram showing the data structure of an offset table
2041. The offset table 2041 is information used for cropping processing by the
playback device 102 in 3D playback mode. "Cropping processing" refers to
processing to generate, from a table representing a 2D video image, a pair of pieces
of plane data that represent a left-view and a right-view. A piece of "plane data"
refers to a two-dimensional array of pixel data. The size of the array is the same as
the resolution of a video frame. A piece of pixel data consists of a chromatic
coordinate value and an a value. The chromatic coordinate value is expressed as an
RGB value or a YCrCb value. The target of cropping processing includes the pieces
of plane data generated from the PG streams, IG streams, and secondary video
streams in the main TS, as well as the pieces of image plane data generated in
accordance with a BD-J object. Cropping processing changes the horizontal position
of each piece of pixel data in a piece of plane data. Accordingly, in the pair of pieces
of plane data obtained via cropping processing, the presentation positions in the
left-view and right-view are shifted to the left and right from the original
presentation position in the 2D video image. A viewer is made to perceive a pair of a
left-view and a right-view as a single 3D video image due to the binocular parallax
produced by these shifts.
[0142] As shown in FIG. 22A, the offset table 2041 includes a table 2210 for each
PID in PG streams, IG streams, and secondary video streams. Each table 2210 is a
correspondence table between PTSs 2201 and offset values 2202. The PTS 2201
represents each piece of plane data generated from PG streams, IG streams, and
secondary video streams. The offset value 2202 represents the signed number of
pixels by which each piece of pixel data is shifted horizontally by cropping
processing. For example, a positive sign represents a shift to the right, and a
negative sign a shift to the left. The sign of the offset value 2202 is determined by
whether the 3D video image is deeper than the screen or closer to the viewer.
Hereinafter, a pair 2203 of a PTS 2201 and an offset value 2202 is referred to as an
"offset entry".
[0143] FIG. 22B is a schematic diagram showing the valid section of an offset entry.
The valid section of an offset entry is, within the time measured by an STC, the
interval from the time indicated by the PTS of the offset entry until the time
indicated by the PTS of the next offset entry. When the PTS for a piece of plane data
belongs to a valid section of a certain offset entry, then during cropping processing,
the presentation position of the pixel data in that piece of plane data shifts by the
offset value in the offset entry. In the example shown in FIG. 22A, the PTS of offset
entry #1 is 180000, the PTS of offset entry #2 is 270000, and the PTS of offset entry
#3 is 360000. In this case, as shown in FIG. 22B, an offset value of "+5" in the
offset entry #1 is valid in an STC range 2204 from 180000 to 270000, and an offset
value of "+3" in the offset entry #2 is valid in an STC range 2205 from 270000 to
360000.
[0144] [Extent Start Point]
[0145] FIG. 23A is a schematic diagram showing the data structure of extent start
points 2042. As shown in FIG. 23A, the "extent start point" 2042 includes a
base-view extent ID (EXT1_ID) 2311 and an SPN 2312. The EXT1_ID 2311 is a
serial number assigned consecutively from the top to the base-view data blocks
belonging to the first file SS (01000.ssif) 244A. One SPN 2312 is assigned to each
EXT1ID 2311 and is the same as the SPN for the source packet located at the top
of the base-view data block identified by the EXT1_ID 2311. This SPN is a serial
number assigned from the top to the source packets included in the base-view data
block group belonging to the first file SS 244A.
[0146] In the data block group in an interleaved arrangement shown in FIG. 15, the
file 2D (01000.m2ts) and the first file SS 244A share the base-view data blocks in
common. However, a data block group recorded at a location where a long jump is
necessary, such as a boundary between recording layers, generally includes a
base-view data block belonging only to either the file 2D 241 or first file SS 244A
(see modification [0] for details). Accordingly, the SPN 2312 that indicates the
extent start point 2042 generally differs from the SPN for the source packet located
at the top of the 2D extent belonging to the file 2D 241.
[0147] FIG. 23B is a schematic diagram showing the data structure of extent start
points 2320 included in the second clip information file (02000.clpi), i.e. the
right-view clip information file 232. As shown in FIG. 23B, the extent start point
2320 includes right-view extent IDs (EXT2_ID) 2321 and SPNs 2322. The
EXT2_IDs 2321 are serial numbers assigned from the top to the right-view data
blocks belonging to the first file SS 244A. One SPN 2322 is assigned to each
EXT2_ID 2321 and is the same as the SPN for the source packet located at the top
of the right-view data block identified by the EXT2_ID 2321. This SPN is a serial
number assigned in order from the top to the source packets included in the
right-view data block group belonging to the first file SS 244A.
[0148] FIG. 23D is a schematic diagram representing the relationship between
right-view extents EXT2[0], EXT2[1], ... belonging to the first file DEP
(02000.m2ts) 242 and the SPNs 2322 shown by the extent start points 2320. As
shown in FIG. 15, the first file DEP 242 and first file SS 244A share right-view data
blocks. Accordingly, as shown in FIG. 23D, each SPN 2322 shown by the extent
start point 2320 is the same as the SPN for the source packet located at the top of
each right-view extent EXT2[0], EXT2[1], ....
[0149] As described below, the extent start point 2042 in the 2D clip information
file 231 and the extent start point 2320 in the right-view clip information file 232 are
used to detect the boundary of data blocks included in each 3D extent when playing
back 3D video images from the first file SS 244A.
[0150] FIG. 23E is a schematic diagram showing an example of the relationship
between 3D extents EXTSS[0], EXTSS[1], ... belonging to the first file SS 244A
and a data block group 2350 on the BD-ROM disc 101. As shown in FIG. 23E, the
data block group 2350 is recorded in an interleaved arrangement like the data block
group shown in FIG. 15. Note that the following description similarly holds for
other arrangements as well. In the data block 2350, the pairs of contiguous
right-view data blocks and base-view data blocks R1+L1, R2+L2, R3+L3, and
R4+L4 can respectively be accessed as 3D extents EXTSS[0], EXTSS[1],
EXTSS[2], and EXTSS[3]. Furthermore, in the nth 3D extent EXTSS[n] (n = 0, 1, 2,
...), the number of source packets included in the base-view data block L(n+1) is, in
the extent start point 2042, the same as the difference A(n+1)-An between SPNs
corresponding to EXT1_ID = n+1 and n (here, A0 = 0). On the other hand, the
number of source packets included in the right-view data block R(n+1) is, in the
extent start point 2320, the same as the difference B(n+1)-Bn between SPNs
corresponding to EXT2_ID = n+1 and n (here, BO = 0).
[0151] When the playback device 102 in L/R mode plays back 3D video images
from the first file SS 244A, in addition to the entry maps in the clip information files
231 and 232, it also refers to the extent start points 2042 and 2320 to specify, from
the PTS for a frame representing the right-view of an arbitrary scene, the LBN for
the sector on which a right-view data block that includes the frame is recorded.
Specifically, the playback device 102 for example first retrieves the SPN associated
with the PTS from the entry map in the right-view clip information file 232.
Suppose the source packet indicated by the SPN is included in the third right-view
extent EXT2[2] in the first file DEP 242, i.e. the right-view data block R3. Next, the
playback device 102 retrieves "B2", the largest SPN before the target SPN, from
among the SPNs 2322 shown by the extent start points 2320 in the right-view clip
information file 232. The playback device 102 also retrieves the corresponding
EXT2_ID "2". Then the playback device 102 retrieves the value "A2" for the SPN
2312 corresponding to the EXT1_ID which is the same as the EXT2_ID "2". The
playback device 102 further seeks the sum B2+A2 of the retrieved SPNs 2322 and
2312. As can be seen from FIG. 23E, this sum B2+A2 is the same as the total
number of source packets included in the data blocks located before the third
right-view data block R3 among the data blocks included in the 3D extent group
EXTSS[0], EXTSS[1], .... Accordingly, this sum B2+A2 multiplied by 192 bytes,
the data amount per source packet, and divided by 2048 bytes, the data amount per
sector, i.e. (B2+A2) x 192 / 2048, is the same as the number of sectors from the top
of the 3D extent group until immediately before the third right-view data block R3.
Using this quotient, the LBN for the sector on which the top of the right-view data
block R3 is recorded can be specified by referring to the file entry for the first file
SS 244A.
[0152] After specifying the LBN via the above-described procedure, the playback
device 102 indicates the LBN to the BD-ROM drive 121. In this way, the 3D extent
group recorded starting with the sector for this LBN, i.e. the 3D extent group
starting with the third right-view data block R3, is read as aligned units.
[0153] The playback device 102 further refers to the extent start points 2042 and
2320 to extract dependent-view data blocks and base-view data blocks alternately
from the read 3D extents. For example, assume that the 3D extent group EXTSS[n]
(n = 0, 1,2, ...) is read in order from the data block group 2350 shown in FIG. 23E.
The playback device 102 first extracts B1 source packets from the top of the 3D
extent EXTSS[0] as the dependent-view data block R1. Next, the playback device
102 extracts the B1th source packet and the subsequent (A1-1) source packets, a total
of Al source packets, as the first base-view data block L1. The playback device 102
then extracts the (B1+A1)th source packet and the subsequent (B2-B1-1) source
packets, a total of (B2-B1) source packets, as the second dependent-view data block
R2. The playback device 102 further extracts the (Al+B2)th source packet and the
subsequent (A2-A1-1) source packets, a total of (A2-A1) source packets, as the
second base-view data block L2. Thereafter, the playback device 102 thus continues
to detect the boundary between data blocks in each 3D extent based on the number
of read source packets, thereby alternately extracting dependent-view and base-view
data blocks. In parallel, the extracted base-view and right-view data blocks are
transmitted to the system target decoder and decoded.
[0154] In this way, the playback device 102 in L/R mode can play back 3D video
images from the first file SS 244A starting at a specific PTS. As a result, the
playback device 102 can in fact benefit from the above-described advantages (A)
and (B) regarding control of the BD-ROM drive 121.
[0155]«File Base»
[0156] FIG. 23C is a schematic diagram representing the base-view data blocks L1,
L2, ... extracted from the first file SS 244A by the playback device 102 in L/R mode.
As shown by FIG. 23C, the SPNs 2312 shown by the extent start points 2042 are the
same as the SPNs for the source packets located at the tops of base-view data blocks.
Base-view data block groups extracted from a single file SS by referring to extent
start points, like the base-view data block group 2330, are referred to as a "file base".
Furthermore, the base-view data blocks included in a file base are referred to as
"base-view extents". Each base-view extent, as shown in FIG. 23C, is referred to by
an extent start point in a 2D clip information file.
[0157] A base-view extent shares the same data, i.e. base-view data block, with a 2D
extent. Accordingly, the file base includes the same main TS as the file 2D. Unlike
2D extents, however, base-view extents are not referred to by a file entry. As
described above, base-view extents refer to extent start points in a clip information
file to extract 3D extents from the file SS. The file base thus differs from a
conventional file by not including a file entry and by needing an extent start point as
a reference for a base-view extent. In this sense, the file base is a "virtual file". In
particular, the file base is not recognized by the file system and does not appear in
the directory/file structure shown in FIG. 2.
[0158] The 3D video content recorded on the BD-ROM disc 101 may have only one
type of sub-TS corresponding to the main TS. FIG. 24 is a schematic diagram
showing the relationships between each extent group in a data block group 2400, file
2D 2410, file base 2411, file DEP 2412, and file SS 2420 which include the content.
As shown in FIG. 24, unlike the data block groups shown in FIG. 15, the data block
group 2400 alternately includes one dependent-view data block D[n] (n = ..., 0, 1, 2,
3, ...) and one base-view data block B[n]. Base-view data blocks B[n] belong to the
file 2D 2410 as 2D extents EXT2D[n]. Dependent-view data blocks D[n] belong to
the file DEP 2412 as dependent-view extents EXT2[n]. Two contiguous
dependent-view data blocks and base-view data blocks, the pairs D[0]+B[0] and
D[1]+B[1], belong to the file SS 2420 as one 3D extent EXTSS[0]. Similarly, two
contiguous dependent-view data blocks and base-view data blocks, the pairs
D[2]+B[2] and D[3]+B[3], belong to the file SS 2420 as one 3D extent EXTSS[0].
The 3D extents EXTSS[0], EXTSS[1] share the base-view data blocks B[n] with the
2D extents EXT2D[n] and share the dependent-view data blocks D[n] with the
dependent-view extents EXT2D[n]. After the 3D extents EXTSS[0], EXTSS[1]
have been read into the playback device 102, they are separated into dependent-view
data blocks D[n] and base-view data blocks B[n]. These base-view data blocks B[n]
belong to the file base 2411 as base-view extents EXTl[n]. The boundary between a
base-view extent EXT1[n] and a dependent-view extent EXT2[n] in each 3D extent
EXTSS[n] is specified referring to the extent start points in the clip information files
respectively assigned to the file 2D 2410 and file DEP 2412.
[0159] «Dependent-View Clip Information File»
[0160] The dependent-view clip information file has the same data structure as the
2D clip information file shown in FIGS. 20-23. Accordingly, the following
description covers the differences between the dependent-view clip information file
and the 2D clip information file. Details on the similarities can be found in the above
description.
[0161] A dependent-view clip information file differs from a 2D clip information
file mainly in the following three points: (i) conditions are placed on the stream
attribute information, (ii) conditions are placed on the entry points, and (iii) the 3D
meta data does not include offset tables.
[0162] (i) When the base-view video stream and the dependent-view video stream
are to be used for playback of 3D video images by a playback device 102 in L/R
mode, as shown in FIG. 7, the dependent-view video stream is compressed using the
base-view video stream. At this point, the video stream attributes of the
dependent-view video stream become equivalent to the base-view video stream. The
video stream attribute information for the base-view video stream is associated with
PID = 0x1011 in the stream attribute information 2020 in the 2D clip information
file. On the other hand, the video stream attribute information for the
dependent-view video stream is associated with PID = 0x1012 or 0x1013 in the
stream attribute information in the dependent-view clip information file.
Accordingly, the items shown in FIG. 20, i.e. the codec, resolution, aspect ratio, and
frame rate, have to match between these two pieces of video stream attribute
information. If the codec type matches, then a reference relationship between
pictures in the base-view video stream and the dependent-view video stream is
established during coding, and thus each picture can be decoded. If the resolution,
aspect ratio, and frame rate all match, then on-screen presentation of the left and
right videos can be synchronized. Therefore, these videos can be shown as 3D video
images without making the viewer feel uncomfortable.
[0163] (ii) The entry map in the dependent-view clip information file includes a
table allocated to the dependent-view video stream. Like the table 2100 shown in
FIG. 21 A, this table includes an entry map header and entry points. The entry map
header indicates the PID for the dependent-view video stream allocated to the table,
i.e. either 0x1012 or 0x1013. In each entry point, a pair of a PTS and an SPN is
associated with a single EP_TD. The PTS for each entry point is the same as the PTS
for the top picture in one of the GOPs included in the dependent-view video stream.
The SPN for each entry point is the same as the top SPN of the source packet group
stored in the picture indicated by the PTS belonging to the same entry point. This
SPN refers to a serial number assigned consecutively from the top to the source
packet group belonging to the file DEP, i.e. the source packet group constituting the
sub-TS. The PTS for each entry point has to match the PTS, within the entry map in
the 2D clip information file, for the entry point in the table allotted to the base-view
video stream. In other words, whenever an entry point is set to the top of a source
packet group that includes one of a set of pictures included in the same 3D VAU, an
entry point always has to be set to the top of the source packet group that includes
the other picture.
[0164] FIG. 25 is a schematic diagram showing an example of entry points set in a
base-view video stream 2510 and a dependent-view video stream 2520. In the two
video streams 2510 and 2520, GOPs that are the same number from the top
represent video for the same playback period. As shown in FIG. 25, in the base-view
video stream 2510, entry points 2501B, 2503B, and 2505B are set to the top of the
odd-numbered GOPS as counted from the top, i.e. GOP #1, GOP #3, and GOP #5.
Accordingly, in the dependent-view video stream 2520 as well, entry points 250ID,
2503D, and 2505D are set to the top of the odd-numbered GOPS as counted from
the top, i.e. GOP #1, GOP #3, and GOP #5. In this case, when the 3D playback
device 102 begins playback of 3D video images from GOP #3, for example, it can
immediately calculate the address of the position to start playback in the file SS
from the SPN of the corresponding entry points 2503B and 2503D. In particular,
when both entry points 2503B and 2503D are set to the top of a data block, then as
can be understood from FIG. 23E, the sum of the SPNs of the entry points 2503B
and 2503D equals the SPN of the position to start playback within the file SS. As
described with reference to FIG. 33E, from this number of source packets, it is
possible to calculate the LBN of the sector on which the part of the file SS for the
position to start playback is recorded. In this way, even during playback of 3D video
images, it is possible to improve response speed for processing that requires random
access to the video stream, such as interrupt playback or the like.
[0165] «2D Playlist File»
[0166] FIG. 26 is a schematic diagram showing the data structure of a 2D playlist
file. The first playlist file (00001.mpls) 221 shown in FIG. 2 has this data structure.
As shown in FIG. 26, the 2D playlist file 221 includes a main path 2601 and two
sub-paths 2602 and 2603.
[0167] The main path 2601 is a sequence of playitem information pieces (PI) that
defines the main playback path for the file 2D 241, i.e. the section for playback and
the section's playback order. Each PI is identified with a unique playitem ID = #N
(N = 1, 2, 3, ...). Each PI #N defines a different playback section along the main
playback path with a pair of PTSs. One of the PTSs in the pair represents the start
time (In-Time) of the playback section, and the other represents the end time
(Out-Time). Furthermore, the order of the Pis in the main path 2601 represents the
order of corresponding playback sections in the playback path.
[0168] Each of the sub-paths 2602 and 2603 is a sequence of sub-playitem
information pieces (SUBPI) that defines a playback path that can be associated in
parallel with the main playback path for the file 2D 241. Such a playback path is a
different section of the file 2D 241 than is represented by the main path 2601, or is a
section of stream data multiplexed in another file 2D, along with the corresponding
playback order. Such stream data represents other 2D video images to be played
back simultaneously with 2D video images played back from the file 2D 241 in
accordance with the main path 2601. These other 2D video images include, for
example, sub-video in a picture-in-picture format, a browser window, a pop-up
menu, or subtitles. Serial numbers "0" and "1" are assigned to the sub-paths 2602
and 2603 in the order of registration in the 2D playlist file 221. These serial numbers
are used as sub-path IDs to identify the sub-paths 2602 and 2603. In the sub-paths
2602 and 2603, each SUB_PI is identified by a unique sub-playitem ID = #M (M =
1, 2, 3, ...). Each SUB_PI #M defines a different playback section along the
playback path with a pair of PTSs. One of the PTSs in the pair represents the
playback start time of the playback section, and the other represents the playback
end time. Furthermore, the order of the SUBPIs in the sub-paths 2602 and 2603
represents the order of corresponding playback sections in the playback path.
[0169] FIG. 27 is a schematic diagram showing the data structure of a PI #N. As
shown in FIG. 27, a PI #N includes a piece of reference clip information 2701,
playback start time (InTime) 2702, playback end time (OutTime) 2703,
connection condition 2704, and stream selection table (hereinafter referred to as
"STN table" (stream number table)) 2705. The reference clip information 2701 is
information for identifying the 2D clip information file 231. The playback start time
2702 and playback end time 2703 respectively indicate PTSs for the beginning and
the end of the section for playback of the file 2D 241. The connection condition
2704 specifies a condition for connecting video in the playback section specified by
a playback start time 2702 and a playback end time 2703 to video in the playback
section specified by the previous PI #(N-1). The STN table 2705 is a list of
elementary streams that can be selected from the file 2D 241 by the decoder in the
playback device 102 from the playback start time 2702 until the playback end time
2703.
[0170] The data structure of a SUBPI is the same as the data structure of the PI
shown in FIG. 27 insofar as it includes reference clip information, a playback start
time, and a playback end time. In particular, the playback start time and playback
end time of a SUBPI are expressed as values along the same time axis as a PL The
SUB_PI further includes an "SP connection condition" field. The SP connection
condition has the same meaning as a PI connection condition.
[0171] [Connection Condition]
[0172] The connection condition 2704 can for example be assigned three types of
values, "1", "5", and "6". When the connection condition 2704 is "1", the video to
be played back from the section of the file 2D 241 specified by the PI #N does not
need to be seamlessly connected to the video played back from the section of the file
2D 241 specified by the immediately preceding PI #N. On the other hand, when the
connection condition 2704 indicates "5" or "6", both video images need to be
seamlessly connected.
[0173] FIGS. 28A and 28B are schematic diagrams showing the relationship
between playback sections 2801 and 2802 that are to be connected when the
connection condition 2704 shown in FIG. 27 indicates "5" and "6". In this case, the
PI #N(N-1) specifies a first section 2801 in the file 2D 241, and the PI #N specifies a
second section 2802 in the file 2D 241. As shown in FIG. 2 8A, when the connection
condition 2704 indicates "5", the STCs of the PI #(N-1) and PI #N may be
nonconsecutive. That is, the PTS #1 at the end of the first section 2801 and the PTS
#2 at the top of the second section 2802 may be nonconsecutive. Several constraint
conditions, however, need to be satisfied. For example, the first section 2801 and
second section 2802 need to be created so that the decoder can smoothly continue to
decode data even when the second section 2802 is supplied to the decoder
consecutively after the first section 2801. Furthermore, the last frame of the audio
stream contained in the first section 2801 needs to overlap the top frame of the audio
stream contained in the second section 2802. On the other hand, as shown in FIG.
28B, when the connection condition 2704 indicates "6", the first section 2801 and
the second section 2802 need to be able to be handled as successive sections for the
decoder to duly decode. That is, STCs and ATCs need to be contiguous between the
first section 2801 and the second section 2802. Similarly, when the SP connection
condition is "5" or "6", STCs and ATCs need to be contiguous between sections of
the file 2D specified by two contiguous SUBPIs.
[0174] [STN Table]
[0175] Referring again to FIG. 27, the STN table 2705 is an array of stream
registration information. "Stream registration information" is information
individually listing the elementary streams that can be selected for playback from
the main TS between the playback start time 2702 and playback end time 2703. The
stream number (STN) 2706 is a serial number allocated individually to stream
registration information and is used by the playback device 102 to identify each
elementary stream. The STN 2706 further indicates priority for selection among
elementary streams of the same type. The stream registration information includes a
stream entry 2709 and stream attribute information 2710. The stream entry 2709
includes stream path information 2707 and stream identification information 2708.
The stream path information 2707 is information indicating the file 2D to which the
selected elementary stream belongs. For example, if the stream path information
2707 indicates "main path", the file 2D corresponds to the 2D clip information file
indicated by reference clip information 2701. On the other hand, if the stream path
information 2707 indicates "sub-path ID = 1", the file 2D to which the selected
elementary stream belongs corresponds to the 2D clip information file indicated by
the reference clip information of the SUBPI included in the sub-path with a
sub-path ID = 1. The playback start time and playback end time specified by this
SUB_PI are both included in the interval from the playback start time 2702 until the
playback end time 2703 specified by the PI included in the STN table 2705. The
stream identification information 2708 indicates the PID for the elementary stream
multiplexed in the file 2D specified by the stream path information 2707. The
elementary stream indicated by this PID can be selected from the playback start time
2702 until the playback end time 2703. The stream attribute information 2710
indicates attribute information for each elementary stream. For example, the
attribute information of an audio stream, a PG stream, and an IG stream indicates a
language type of the stream.
[0176] [Playback of 2D Video Images in Accordance With a 2D Playlist File]
[0177] FIG. 29 is a schematic diagram showing the relationships between the PTSs
indicated by the 2D playlist file (00001.mpls) 221 and the sections played back from
the file 2D (01000.m2ts) 241. As shown in FIG. 29, in the main path 2601 in the 2D
playlist file 221, the PI #1 specifies a PTS #1, which indicates a playback start time
IN1, and a PTS #2, which indicates a playback end time OUT1. The reference clip
information 2701 for the PI #1 indicates the 2D clip information file (01000.clpi)
231. When playing back 2D video images in accordance with the 2D playlist file
221, the playback device 102 first reads the PTS #1 and PTS #2 from the PI #1.
Next, the playback device 102 refers to the entry map in the 2D clip information file
231 to retrieve from the file 2D 241 the SPN #1 and SPN #2 that correspond to the
PTS #1 and PTS #2. The playback device 102 then calculates the corresponding
numbers of sectors from the SPN #1 and SPN #2. Furthermore, the playback device
102 refers to these numbers of sectors and the file entry for the file 2D 241 to
specify the LBN #1 and LBN #2 at the beginning and end, respectively, of the sector
group PI on which the 2D extent group EXT2D[0], ..., EXT2D[n] to be played back
is recorded. Calculation of the numbers of sectors and specification of the LBNs are
as per the description of FIGS. 21B and 21C. Finally, the playback device 102
indicates the range from LBN #1 to LBN #2 to the BD-ROM drive 121. The source
packet group belonging to the 2D extent group EXT2D[0], ..., EXT2D[n] is thus
read from the sector group PI in this range. Similarly, the pair PTS #3 and PTS #4
indicated by the PI #2 are first converted into a pair of SPN #3 and SPN #4 by
referring to the entry map in the 2D clip information file 231. Then, referring to the
file entry for the file 2D 241, the pair of SPN #3 and SPN #4 are converted into a
pair of LBN #3 and LBN #4. Furthermore, a source packet group belonging to the
2D extent group is read from the sector group P2 in a range from the LBN #3 to the
LBN #4. Conversion of a pair of PTS #5 and PTS #6 indicated by the PI #3 to a pair
of SPN #5 and SPN #6, conversion of the pair of SPN #5 and SPN #6 to a pair of
LBN #5 and LBN #6, and reading of a source packet group from the sector group P3
in a range from the LBN #5 to the LBN #6 are similarly performed. The playback
device 102 thus plays back 2D video images from the file 2D 241 in accordance
with the main path 2601 in the 2D playlist file 221.
[0178] The 2D playlist file 221 may include an entry mark 2901. The entry mark
2901 indicates a time point in the main path 2601 at which playback is actually to
start. For example, as shown in FIG. 29, multiple entry marks 2901 can be set for the
PI #1. The entry mark 2901 is particularly used for searching for a position to start
playback during random access. For example, when the 2D playlist file 221 specifies
a playback path for a movie title, the entry marks 2901 are assigned to the top of
each chapter. Consequently, the playback device 102 can play back the movie title
by chapters.
[0179] «3D Playlist File»
[0180] FIG. 30 is a schematic diagram showing the data structure of a 3D playlist
file. The second playlist file (00002.mpls) 222 shown in FIG. 2 has this data
structure, as does the second playlist file (00003.mpls) 223. As shown in FIG. 30,
the 3D playlist file 222 includes a main path 3001, sub-path 3002, and extension
data 3003.
[0181] The main path 3001 specifies the playback path of the main TS shown in FIG.
3A. Accordingly, the main path 3001 is the same as the main path 2601 for the 2D
playlist file 221 shown in FIG. 26. The playback device 102 in 2D playback mode
can play back 2D video images from the file 2D 241 in accordance with the main
path 3001 in the 3D playlist file 222.
[0182] The sub-path 3002 specifies the playback path for the sub-TSs shown in
FIGS. 3B and 3C, i.e. the playback path for both the first file DEP 242 and the
second file DEP 243. The data structure of the sub-path 3002 is the same as the data
structure of the sub-paths 2602 and 2603 in the 2D playlist file 241 shown in FIG.
26. Accordingly, details on this similar data structure can be found in the description
of FIG. 26, in particular details on the data structure of the SUBPI.
[0183] The SUB_PI #N (N = 1, 2, 3, ...) in the sub-path 3002 are in one-to-one
correspondence with the PI #N in the main path 3001. Furthermore, the playback
start time and playback end time specified by each SUB_PI #N is the same as the
playback start time and playback end time specified by the corresponding PI #N.
The sub-path 3002 additionally includes a sub-path type 3010. The "sub-path type"
generally indicates whether playback processing should be synchronized between
the main path and the sub-path. In the 3D playlist file 222, the sub-path type 3010 in
particular indicates the type of the 3D playback mode, i.e. the type of the
dependent-view video stream to be played back in accordance with the sub-path
3002. In FIG. 30, the value of the sub-path type 3010 is "3D L/R", thus indicating
that the 3D playback mode is L/R mode, i.e. that the right-view video stream is to be
played back. On the other hand, a value of "3D depth" for the sub-path type 3010
indicates that the 3D playback mode is depth mode, i.e. that the depth map stream is
to be played back. When the playback device 102 in 3D playback mode detects that
the value of the sub-path type 3010 is "3D L/R" or "3D depth", the playback device
102 synchronizes playback processing in accordance with the main path 3001 with
playback processing in accordance with the sub-path 3002.
[0184] Only the playback device 102 in 3D playback mode interprets the extension
data 3003; the playback device 102 in 2D playback mode ignores the extension data
3003. In particular, the extension data 3003 includes an extension stream selection
table 3030. The "extension stream selection table (STN_table_SS)" (hereinafter
abbreviated as STN table SS) is an array of stream registration information to be
added to the STN tables indicated by each PI in the main path 3001. This stream
registration information indicates elementary streams that can be selected for
playback from the main TS.
[0185] FIG. 31 is a schematic diagram showing the data structure of an STN table
SS 3030. As shown in FIG. 31, an STN table SS 3030 includes stream registration
information sequences 3101, 3102, 3103, .... The stream registration information
sequences 3101, 3102, 3103, ... individually correspond to the PI #1, PI #2, PI #3,
... in the main path 3001 and are used by the playback device 102 in 3D playback
mode in combination with the stream registration information sequences included in
the STN tables in the corresponding PIs. The stream registration information
sequence 3101 corresponding to each PI includes an offset during popup
(Fixed_offset_during_Popup) 3111, stream registration information sequence 3112
for the dependent-view video streams, stream registration information sequence
3113 for the PG stream, and stream registration information sequence 3114 for the
IG stream.
[0186] The offset during popup 3111 indicates whether a popup menu is played
back from the IG stream. The playback device 102 in 3D playback mode changes
the presentation mode of the video plane and the PG plane in accordance with the
value of the offset 3111. There are two types of presentation modes for the video
plane: base-view (B) - dependent-view (D) presentation mode and B-B presentation
mode. There are three types of presentation modes for the PG plane and IG plane: 2
plane mode, 1 plane + offset mode, and 1 plane + zero offset mode. For example,
when the value of the offset during popup 3111 is "0", a popup menu is not played
back from the IG stream. At this point, B-D presentation mode is selected as the
video plane presentation mode, and 2 plane mode or 1 plane + offset mode is
selected as the presentation mode for the PG plane. On the other hand, when the
value of the offset during popup 3111 is "1", a popup menu is played back from the
IG stream. At this point, B-B presentation mode is selected as the video plane
presentation mode, and 1 plane + zero offset mode is selected as the presentation
mode for the PG plane.
[0187] In "B-D presentation mode", the playback device 102 alternately outputs
plane data decoded from the left-view and right-view video streams. Accordingly,
since left-view and right-view video frames representing video planes are alternately
displayed on the screen of the display device 103, a viewer perceives these frames as
3D video images. In "B-B presentation mode", the playback device 102 outputs
plane data decoded only from the base-view video stream twice for a frame while
maintaining the operation mode in 3D playback mode (in particular, maintaining the
frame rate at the value for 3D playback, e.g. 48 frames/second). Accordingly, only
either the left-view or right-view frames are displayed on the screen of the playback
device 103, and thus a viewer perceives these frames simply as 2D video images.
[0188] In "2 plane mode", when the sub-TS includes both left-view and right-view
graphics streams, the playback device 102 decodes and alternately outputs left-view
and right-view graphics plane data from the graphics streams. In "1 plane + offset
mode", the playback device 102 generates a pair of left-view plane data and
right-view plane data from the graphics stream in the main TS via cropping
processing and alternately outputs these pieces of plane data. In both of these modes,
left-view and right-view PG planes are alternately displayed on the screen of the
display device 103, and thus a viewer perceives these frames as 3D video images. In
"1 plane + zero offset mode", the playback device 102 temporarily stops cropping
processing and outputs plane data decoded from the graphics stream in the main TS
twice for a frame while maintaining the operation mode in 3D playback mode.
Accordingly, only either the left-view or right-view PG planes are displayed on the
screen of the playback device 103, and thus a viewer perceives these planes simply
as 2D video images.
[0189] The playback device 102 in 3D playback mode refers to the offset during
popup 3111 for each PI and selects B-B presentation mode and 1 plane + zero offset
mode when a popup menu is played back from an IG stream. While a pop-up menu
is displayed, other 3D video images are thus temporarily changed to 2D video
images. This improves the visibility and usability of the popup menu.
[0190] The stream registration information sequence 3112 for the dependent-view
video stream, the stream registration information sequence 3113 for the PG streams,
and the stream registration information sequence 3114 for the IG streams each
include stream registration information indicating the dependent-view video streams,
PG streams, and IG streams that can be selected for playback from the sub-TS.
These stream registration information sequences 3112,3113, and 3114 are each used
in combination with stream registration information sequences, located in the STN
table of the corresponding PI, that respectively indicate base-view streams, PG
streams, and IG streams. When reading a piece of stream registration information
from an STN table, the playback device 102 in 3D playback mode automatically
also reads the stream registration information sequence, located in the STN table SS,
that has been combined with the piece of stream registration information. When
simply switching from 2D playback mode to 3D playback mode, the playback
device 102 can thus maintain already recognized STNs and stream attributes such as
language.
[0191] FIG. 32A is a schematic diagram showing the data structure of a stream
registration information sequence 3112 for dependent-view video streams. As shown
in FIG. 32A, this stream registration information sequence 3112 generally includes a
plurality of pieces of stream registration information (SS_dependent_view_block)
3201. These are the same in number as the pieces of stream registration information
in the corresponding PI that indicate the base-view video stream. Each piece of
stream registration information 3201 includes an STN 3211, stream entry 3212, and
stream attribute information 3213. The STN 3211 is a serial number assigned
individually to pieces of stream registration information 3201 and is the same as the
STN of the piece of stream registration information, located in the corresponding PI,
with which each piece of stream registration information is combined. The stream
entry 3212 includes sub-path ID reference information (ref_to_subpath_id) 3221,
stream file reference information (ref_to_subclip_entry_id) 3222, and PID
(ref_to_stream_PID_subclip) 3223. The sub-path ID reference information 3221
indicates the sub-path ID of the sub-path that specifies the playback path of the
dependent-view video stream. The stream file reference information 3222 is
information to identify the file DEP storing this dependent-view video stream. The
PID 3223 is the PID for this dependent-view video stream. The stream attribute
information 3213 includes attributes for this dependent-view video stream, such as
frame rate, resolution, and video format. In particular, these attributes are the same
as those for the base-view video stream shown by the piece of stream registration
information, located in the corresponding PI, with which each piece of stream
registration information is combined.
[0192] FIG. 32B is a schematic diagram showing the data structure of a stream
registration information sequence 3113 for PG streams. As shown in FIG. 32B, this
stream registration information sequence 3113 generally includes a plurality of
pieces of stream registration information 3231. These are the same in number as the
pieces of stream registration information in the corresponding PI that indicates the
PG streams. Each piece of stream registration information 3231 includes an STN
3241, stereoscopic flag (is_SS_PG) 3242, base-view stream entry
(stream_entry_for_base_view) 3243, dependent-view stream entry
(stream_entry_for_dependent_view) 3244, and stream attribute information 3245.
The STN 3241 is a serial number assigned individually to pieces of stream
registration information 3231 and is the same as the STN of the piece of stream
registration information, located in the corresponding PI, with which each piece of
stream registration information 3231 is combined. The stereoscopic flag 3242
indicates whether both base-view and dependent-view, e.g. left-view and right-view,
PG streams are included on a BD-ROM disc 101. If the stereoscopic flag 3242 is on,
both PG streams are included in the sub-TS. Accordingly, the playback device reads
all of the fields in the base-view stream entry 3243, the dependent-view stream entry
3244, and the stream attribute information 3245. If the stereoscopic flag 3242 is off,
the playback device ignores all of these fields 3243-3245. Both the base-view stream
entry 3243 and the dependent-view stream entry 3244 include sub-path ID reference
information, stream file reference information, and a PID. The sub-path ID reference
information indicates the sub-path IDs of the sub-paths that specify the playback
paths of the base-view and dependent-view PG streams. The stream file reference
information is information to identify the file DEP storing the PG streams. The PIDs
are the PIDs for the PG streams. The stream attribute information 3245 includes
attributes for the PG streams, e.g. language type.
[0193] FIG. 32C is a schematic diagram showing the data structure of a stream
registration information sequence 3114 for IG streams. As shown in FIG. 32C, this
stream registration information sequence 3114 generally includes a plurality of
pieces of stream registration information 3251. These are the same in number as the
pieces of stream registration information in the corresponding PI that indicates the
IG streams. Each piece of stream registration information 3251 includes an STN
3261, stereoscopic flag (is_SS_IG) 3262, base-view stream entry 3263,
dependent-view stream entry 3264, and stream attribute information 3265. The STN
3261 is a serial number assigned individually to pieces of stream registration
information 3251 and is the same as the STN of the piece of stream registration
information, located in the corresponding PI, with which each piece of stream
registration information 3251 is combined. The stereoscopic flag 3262 indicates
whether both base-view and dependent-view, e.g. left-view and right-view, IG
streams are included on a BD-ROM disc 101. If the stereoscopic flag 3262 is on,
both IG streams are included in the sub-TS. Accordingly, the playback device reads
all of the fields in the base-view stream entry 3263, the dependent-view stream entry
3264, and the stream attribute information 3265. If the stereoscopic flag 3262 is off,
the playback device ignores all of these fields 3263-3265. Both the base-view stream
entry 3263 and the dependent-view stream entry 3264 include sub-path ID reference
information, stream file reference information, and a PID. The sub-path ID reference
information indicates the sub-path IDs of the sub-paths that specify the playback
paths of the base-view and dependent-view IG streams. The stream file reference
information is information to identify the file DEP storing the IG streams. The PIDs
are the PIDs for the IG streams. The stream attribute information 3265 includes
attributes for the IG streams, e.g. language type.
[0194] [Playback of 3D Video Images in Accordance With a 3D Playlist File]
[0195] FIG. 33 is a schematic diagram showing the relationships between the PTSs
indicated by the 3D playlist file (00002.mpls) 222 and the sections played back from
the first file SS (01000.ssif) 244A. As shown in FIG. 33, in the main path 3001 of
the 3D playlist file 222, the PI #1 specifies a PTS #1, which indicates a playback
start time INI, and a PTS #2, which indicates a playback end time OUT1. The
reference clip information for the PI #1 indicates the 2D clip information file
(01000.clpi) 231. In the sub-path 3002, which indicates that the sub-path type is "3D
L/R", the SUB_PI #1 specifies the same PTS #1 and PTS #2 as the PI #1. The
reference clip information for the SUBPI #1 indicates the right-view clip
information file (02000.clpi) 232.
[0196] When playing back 3D video images in accordance with the 3D playlist file
222, the playback device 102 first reads PTS #1 and PTS #2 from the PI #1 and
SUB_PI #1. Next, the playback device 102 refers to the entry map in the 2D clip
information file 231 to retrieve from the file 2D 241 the SPN #1 and SPN #2 that
correspond to the PTS #1 and PTS #2. In parallel, the playback device 102 refers to
the entry map in the right-view clip information file 232 to retrieve from the first file
DEP 242 the SPN #11 and SPN #12 that correspond to the PTS #1 and PTS #2. As
described with reference to FIG. 23E, the playback device 102 then uses the extent
start points 2042 and 2320 in the clip information files 231 and 232 to calculate,
from SPN #1 and SPN #11, the number of source packets SPN #21 from the top of
the first file SS 244A to the position to start playback. Similarly, the playback device
102 calculates, from SPN #2 and SPN #12, the number of source packets SPN #22
from the top of the first file SS 244A to the position to start playback. The playback
device 102 further calculates the numbers of sectors corresponding to the SPN #21
and SPN #22. Next, the playback device 102 refers to these numbers of sectors and
the allocation descriptors in the file entry for the file SS 244A to specify the LBN #1
and LBN #2 at the beginning and end, respectively, of the sector group Pll on
which the 3D extent group EXTSS[0], ..., EXTSS[n] to be played back is recorded.
Calculation of the numbers of sectors and specification of the LBNs are as per the
description of FIG. 23E. Finally, the playback device 102 indicates the range from
LBN #1 to LBN #2 to the BD-ROM drive 121. The source packet group belonging
to the 3D extent group EXTSS[0], ..., EXTSS[n] is thus read from the sector group
PI 1 in this range. Similarly, the pair PTS #3 and PTS #4 indicated by the PI #2 and
SUB_PI #2 are first converted into a pair of SPN #3 and SPN #4 and a pair of SPN
#13 and SPN #14 by referring to the entry maps in the clip information files 231 and
232. Then, the number of source packets SPN #23 from the top of the first file SS
244A to the position to start playback is calculated from SPN #3 and SPN #13, and
the number of source packets SPN #24 from the top of the first file SS 244A to the
position to end playback is calculated from SPN #4 and SPN #14. Next, referring to
the file entry for the first file SS 244A, the pair of SPN #23 and SPN #24 are
converted into a pair of LBN #3 and LBN #4. Furthermore, a source packet group
belonging to the 3D extent group is read from the sector group P12 in a range from
the LBN #3 to the LBN #4.
[0197] In parallel with the above-described read processing, as described with
reference to FIG. 23E, the playback device 102 refers to the extent start points 2042
and 2320 in the clip information files 231 and 232 to extract base-view extents from
each 3D extent and decode the base-view extents in parallel with the remaining
right-view extents. The playback device 102 can thus play back 3D video images
from the first file SS 244A in accordance with the 3D playlist file 222.
[0198] «Index Table»
[0199] FIG. 34 is a schematic diagram showing an index table 3410 in the index file
(index.bdmv) 211 shown in FIG. 2. As shown in FIG. 34, the index table 3410 stores
the items "first play" 3401, "top menu" 3402, and "title k" 3403 (k = 1, 2, ..., n; an
integer n is equal to or greater than one). Each item is associated with either a movie
object MVO-2D, MVO-3D, ..., or with a BD-J object BDJO-2D, BDJO-3D,....
Each time a title or a menu is called in response to a user operation or an application
program, a control unit in the playback device 102 refers to a corresponding item in
the index table 3410. Furthermore, the control unit calls an object associated with
the item from the BD-ROM disc 101 and accordingly executes a variety of
processes. Specifically, the "first play" 3401 specifies an object to be called when
the disc 101 is loaded into the BD-ROM drive 121. The "top menu" 3402 specifies
an object for displaying a menu on the display device 103 when a command "go
back to menu" is input, for example, by user operation. In the "title k" 3403, the
titles that constitute the content on the disc 101 are individually allocated. For
example, when a title for playback is specified by user operation, in the item "title
k" in which the title is allocated, the object for playing back a video from the AV
stream file corresponding to the title is specified.
[0200] In the example shown in FIG. 34, the items "title 1" and "title 2" are
allocated to titles of 2D video images. The movie object associated with the item
"title 1", MVO-2D, includes a group of commands related to playback processes for
2D video images using the 2D playlist file (00001.mpls) 221. When the playback
device 102 refers to the item "title 1", then in accordance with the movie object
MVO-2D, the 2D playlist file 221 is read from the disc 101, and playback processes
for 2D video images are executed in accordance with the playback path specified
therein. The BD-J object associated with the item "title 2", BDJO-2D, includes an
application management table related to playback processes for 2D video images
using the 2D playlist file 221. When the playback device 102 refers to the item "title
2", then in accordance with the application management table in the BD-J object
BDJO-2D, a Java application program is called from the JAR file 261 and executed.
In this way, the 2D playlist file 221 is read from the disc 101, and playback
processes for 2D video images are executed in accordance with the playback path
specified therein.
[0201] Furthermore, in the example shown in FIG. 34, the items "title 3" and "title
4" are allocated to titles of 3D video images. The movie object associated with the
item "title 3", MVO-3D, includes, in addition to a group of commands related to
playback processes for 2D video images using the 2D playlist file 221, a group of
commands related to playback processes for 3D video images using either 3D
playlist file (00002.mpls) 222 or (00003.mpls) 223. In the BD-J object associated
with the item "title 4", BDJO-3D, the application management table specifies, in
addition to a Java application program related to playback processes for 2D video
images using the 2D playlist file 221, a Java application program related to playback
processes for 3D video images using either 3D playlist file 222 or 223.
[0202] When the playback device 102 refers to item "title 3", the following four
determination processes are performed in accordance with the movie object
MVO-3D: (1) does the playback device 102 itself support playback of 3D video
images? (2) has the user selected playback of 3D video images? (3) does the display
device 103 support playback of 3D video images? and (4) is the 3D video playback
mode of the playback device 102 in L/R mode or depth mode? Next, in accordance
with the results of these determinations, one of the playlist files 221-223 is selected
for playback. When the playback device 102 refers to item "title 4", a Java
application program is called from the JAR file 261, in accordance with the
application management table in the BD-J object BDJO-3D, and executed. The
above-described determination processes are thus performed, and a playlist file is
then selected in accordance with the results of determination.
[0203] [Selection of Playlist File When Selecting a 3D Video Title]
[0204] FIG. 35 is a flowchart of selection processing for a playlist file to be played
back, the processing being performed when a 3D video title is selected. In the index
table 3410 shown in FIG. 34, selection processing is performed in accordance with
the movie object MVO-3D when referring to the item "title 3", and selection
processing is performed in accordance with the Java application program specified
by the BD-J object BDJO-3D when referring to the item "title 4".
[0205] In light of this selection processing, it is assumed that the playback device
102 includes a first flag and a second flag. A value of "0" for the first flag indicates
that the playback device 102 only supports playback of 2D video images, whereas
"1" indicates support of 3D video images as well. A value of "0" for the second flag
indicates that the playback device 102 is in L/R mode, whereas "1" indicates depth
mode.
[0206] In step S3501, the playback device 102 checks the value of the first flag. If
the value is "0", processing proceeds to step S3505. If the value is "1", processing
proceeds to step S3502.
[0207] In step S3502, the playback device 102 displays a menu on the display
device 103 for the user to select playback of either 2D or 3D video images. If the
user selects playback of 2D video images via operation of a remote control 105 or
the like, processing proceeds to step S3505, whereas if the user selects 3D video
images, processing proceeds to step S3503.
[0208] In step S3503, the playback device 102 checks whether the display device
103 supports playback of 3D video images. Specifically, the playback device 102
exchanges CEC messages with the display device 103 via an HDMI cable 122 to
check with the display device 103 as to whether it supports playback of 3D video
images. If the display device 103 does support playback of 3D video images,
processing proceeds to step S3504. If not, processing proceeds to step S3505.
[0209] In step S3504, the playback device 102 checks the value of the second flag.
If this value is "0", processing proceeds to step S3506. If this value is "1",
processing proceeds to step S3507.
[0210] In step S3505, the playback device 102 selects for playback the 2D playlist
file 221. Note that, at this time, the playback device 102 may cause the display
device 103 to display the reason why playback of 3D video images was not selected.
Processing then terminates.
[0211] In step S3506, the playback device 102 selects for playback the 3D playlist
file 222 used in L/R mode. Processing then terminates.
[0212] In step S3507, the playback device 102 selects for playback the 3D playlist
file 223 used in depth mode. Processing then terminates.
[0213]
[0214] When playing back 2D video contents from a BD-ROM disc 101 in 2D
playback mode, the playback device 102 operates as a 2D playback device. FIG. 36
is a functional block diagram of a 2D playback device 3600. As shown in FIG. 36,
the 2D playback device 3600 includes a BD-ROM drive 3601, playback unit 3602,
and control unit 3603. The playback unit 3602 includes a read buffer 3621, system
target decoder 3622, and plane adder 3623. The control unit 3603 includes a
dynamic scenario memory 3631, static scenario memory 3632, user event processing
unit 3633, program execution unit 3634, playback control unit 3635, player variable
storage unit 3636, and decoder driver 3637. The playback unit 3602 and the control
unit 3603 are each implemented on a different integrated circuit, but may
alternatively be implemented on a single integrated circuit.
[0215] When the BD-ROM disc 101 is loaded into the BD-ROM drive 3601, the
BD-ROM drive 3601 radiates laser light to the disc 101 and detects change in the
light reflected from the disc 101. Furthermore, using the change in the amount of
reflected light, the BD-ROM drive 3601 reads data recorded on the disc 101.
Specifically, the BD-ROM drive 3601 has an optical pickup, i.e. an optical head.
The optical head has a semiconductor laser, a collimate lens, a beam splitter, an
objective lens, a collecting lens, and an optical detector. A beam of light radiated
from the semiconductor laser sequentially passes through the collimate lens, the
beam splitter, and the objective lens to be collected on a recording layer of the disc
101. The collected beam is reflected and diffracted by the recording layer. The
reflected and diffracted light passes through the objective lens, the beam splitter, and
the collecting lens, and is collected onto the optical detector. The optical detector
generates a playback signal at a level in accordance with the amount of collected
light. Furthermore, data is decoded from the playback signal.
[0216] The BD-ROM drive 3601 reads data from the BD-ROM disc 101 based on a
request from the playback control unit 3635. Out of the read data, the extents in the
file 2D, i.e. the 2D extents, are transferred to the read buffer 3621; dynamic scenario
information is transferred to the dynamic scenario memory 3631; and static scenario
information is transferred to the static scenario memory 3632. "Dynamic scenario
information" includes an index file, movie object file, and BD-J object file. "Static
scenario information" includes a 2D playlist file and a 2D clip information file.
[0217] The read buffer 3621, the dynamic scenario memory 3631, and the static
scenario memory 3632 are each a buffer memory. A memory element in the
playback unit 3602 is used as the read buffer 3621. Memory elements in the control
unit 3603 are used as the dynamic scenario memory 3631 and the static scenario
memory 3632. Alternatively, different areas in a single memory element may be
used as part or all of these buffer memories 3621, 3631, and 3632. The read buffer
3621 stores 2D extents, the dynamic scenario memory 3631 stores dynamic scenario
information, and the static scenario memory 3632 stores static scenario information.
[0218] The system target decoder 3622 reads 2D extents from the read buffer 3621
in units of source packets and demultiplexes the 2D extents. The system target
decoder 3622 then decodes each of the elementary streams obtained by the
demultiplexing. At this point, information necessary for decoding each elementary
stream, such as the type of codec and attributes of the stream, is transferred from the
playback control unit 3635 to the system target decoder 3622 via the decoder driver
3637. The system target decoder 3622 outputs a primary video stream, secondary
video stream, IG stream, and PG stream respectively as primary video plane data,
secondary video plane data, IG plane data, and PG plane data, in units of VAUs. On
the other hand, the system target decoder 3622 mixes the decoded primary audio
stream and secondary audio stream and transmits the resultant data to an audio
output device, such as an internal speaker 103A of the display device 103. In
addition, the system target decoder 3622 receives graphics data from the program
execution unit 3634 via the decoder driver 3637. The graphics data is used for
rendering graphics such as a GUI menu on a screen and is in a raster data format
such as JPEG and PNG. The system target decoder 3622 processes the graphics data
and outputs the data as image plane data. Details on the system target decoder 3622
are described below.
[0219] The plane adder 3623 receives primary video plane data, secondary video
plane data, IG plane data, PG plane data, and image plane data from the system
target decoder 3622 and superimposes these pieces of plane data to generate one
composite video frame or field. The composited video data is transferred to the
display device 103 for display on the screen.
[0220] The user event processing unit 3633 detects a user operation via the remote
control 105 or the front panel of the playback device 102. Based on the user
operation, the user event processing unit 3633 requests the program execution unit
3634 or the playback control unit 3635 to perform a relevant process. For example,
when a user instructs to display a pop-up menu by pushing a button on the remote
control 105, the user event processing unit 3633 detects the push and identifies the
button. The user event processing unit 3633 further requests the program execution
unit 3634 to execute a command corresponding to the button, i.e. a command to
display the pop-up menu. On the other hand, when a user pushes a fast-forward or a
rewind button on the remote control 105, for example, the user event processing unit
3633 detects the push, identifies the button, and requests the playback control unit
3635 to fast-forward or rewind the playlist currently being played back.
[0221] The program execution unit 3634 is a processor that reads programs from
movie object files and BD-J object files stored in the dynamic scenario memory
3631 and executes these programs. Furthermore, the program execution unit 3634
performs the following operations in accordance with the programs. (1) The
program execution unit 3634 orders the playback control unit 3635 to perform
playlist playback processing. (2) The program execution unit 3634 generates
graphics data for a menu or game as PNG or JPEG raster data and transfers the
generated data to the system target decoder 3622 to be composited with other video
data. Via program design, specific details on these processes can be designed
relatively flexibly. In other words, during the authoring process of the BD-ROM
disc 101, the nature of these processes is determined while programming the movie
object files and BD-J object files.
[0222] The playback control unit 3635 controls transfer of different types of data,
such as 2D extents, an index file, etc. from the BD-ROM disc 101 to the read buffer
3621, the dynamic scenario memory 3631, and the static scenario memory 3632. A
file system managing the directory file structure shown in FIG. 2 is used for this
control. That is, the playback control unit 3635 causes the BD-ROM drive 3601 to
transfer the files to each of the buffer memories 3631, 3631, and 3632 using a
system call for opening files. The "file opening" is composed of a series of the
following processes. First, a file name to be detected is provided to the file system
by a system call, and an attempt is made to detect the file name from the
directory/file structure. When the detection is successful, the file entry for the target
file is first transferred to memory in the playback control unit 3635, and an FCB
(File Control Block) is generated in the memory. Subsequently, a file handle for the
target file is returned from the file system to the playback control unit 3635. After
this, the playback control unit 3635 can transfer the target file from the BD-ROM
disc 101 to each of the buffer memories 3621, 3631, and 3632 by showing the file
handle to the BD-ROM drive 3601.
[0223] The playback control unit 3635 decodes the file 2D to output video data and
audio data by controlling the BD-ROM drive 3601 and the system target decoder
3622. Specifically, the playback control unit 3635 first reads a 2D playlist file from
the static scenario memory 3632, in response to an instruction from the program
execution unit 3634 or a request from the user event processing unit 3633, and
interprets the content of the file. In accordance with the interpreted content,
particularly with the playback path, the playback control unit 3635 then specifies a
file 2D to be played back and instructs the BD-ROM drive 3601 and the system
target decoder 3622 to read and decode this file. Such playback processing based on
a playlist file is called "playlist playback". In addition, the playback control unit
3635 sets various types of player variables in the player variable storage unit 3636
using the static scenario information. With reference to the player variables, the
playback control unit 3635 further specifies to the system target decoder 3622
elementary streams to be decoded and provides the information necessary for
decoding the elementary streams.
[0224] The player variable storage unit 3636 is composed of a group of registers for
storing player variables. Types of player variables include system parameters
(SPRM) and general parameters (GPRM). FIG. 37 is a list of SPRMs. Each SPRM
is assigned a serial number 3701, and each serial number 3701 is associated with a
unique variable value 3702. The contents of major SPRMs are shown below. Here,
the numbers in parentheses indicate the serial numbers 3701.
[0225] SPRM(0) : Language code
SPRM(l) : Primary audio stream number
SPRM(2) : Subtitle stream number
SPRM(3) : Angle number
SPRM(4) : Title number
SPRM(5) : Chapter number
SPRM(6) : Program number
SPRM(7) : Cell number
SPRM(8) : Key name
SPRM(9) : Navigation timer
SPRM(10) : Current playback time
SPRM(11) : Player audio mixing mode for Karaoke
SPRM(12) : Country code for parental management
SPRM(13) : Parental level
SPRM(14) : Player configuration for Video
SPRM(15) : Player configuration for Audio
SPRM(16) : Language code for audio stream
SPRM(17) : Language code extension for audio stream
SPRM(18) : Language code for subtitle stream
SPRM(19) : Language code extension for subtitle stream
SPRM(20) : Player region code
SPRM(21) : Secondary video stream number
SPRM(22) : Secondary audio stream number
SPRM(23) : Player status
SPRM(24) : Reserved
SPRM(25) : Reserved
SPRM(26) : Reserved
SPRM(27) : Reserved
SPRM(28) : Reserved
SPRM(29) : Reserved
SPRM(30) : Reserved
SPRM(31) : Reserved
[0226] The SPRM(IO) indicates the PTS of the picture currently being decoded and
is updated every time a picture is decoded and written into the primary video plane
memory. Accordingly, the current playback point can be known by referring to the
SPRM(10).
[0227] The language code for audio stream in SPRM(16) and the language code for
subtitle stream in SPRM(18) show default language codes of the playback device
102. These codes may be changed by a user with use of the on-screen display (OSD)
or the like for the playback device 102, or may be changed by an application
program via the program execution unit 3634. For example, if the SPRM(16) shows
"English", in playback processing of a playlist, the playback control unit 3635 first
searches the STN table in the PI for a stream entry having the language code for
"English". The playback control unit 3635 then extracts the PID from the stream
identification information of the stream entry and transmits the extracted PID to the
system target decoder 3622. As a result, an audio stream having the same PID is
selected and decoded by the system target decoder 3622. These processes can be
executed by the playback control unit 3635 with use of the movie object file or the
BD-J object file.
[0228] During playback processing, the playback control unit 3635 updates the
player variables in accordance with the status of playback. The playback control unit
3635 updates the SPRM(l), SPRM(2), SPRM(21), and SPRM(22) in particular.
These SPRM respectively show, in the stated order, the STN of the audio stream,
subtitle stream, secondary video stream, and secondary audio stream that are
currently being processed. For example, suppose that the audio stream number
SPRM(l) has been changed by the program execution unit 3634. In this case, the
playback control unit 3635 first refers to the STN shown by the new SPRM(l) and
retrieves the stream entry that includes this STN from the STN table in the PI
currently being played back. The playback control unit 3635 then extracts the PID
from the stream identification information in the stream entry and transmits the
extracted PID to the system target decoder 3622. As a result, the audio stream
having the same PID is selected and decoded by the system target decoder 3622.
This is how the audio stream targeted for playback is switched. The subtitle stream
and the secondary video stream to be played back can be similarly switched.
[0229] The decoder driver 3637 is a device driver for the system target decoder 3622
and functions as an interface between the system target decoder 3622 on the one
hand and the program execution unit 3634 and playback control unit 3635 on the
other. Specifically, the program execution unit 3634 and playback control unit 3635
transmit instructions for the system target decoder 3622 to the decoder driver 3637.
The decoder driver 3637 then converts these instructions into commands in
conformity with the actual hardware in the system target decoder 3622 and transfers
these commands to the system target decoder 3622.
[0230] Furthermore, when causing the system target decoder 3622 to decode
pictures from 2D extents, the decoder driver 3637 participates in the decoding
process as follows. The decoder driver 3637 first causes the system target decoder
3622 to analyze the header of the VAU that includes the picture to be decoded. This
header includes the sequence header 931B, picture header 931C, and supplementary
data 931D, as well as the slice headers in the compressed picture data 931E, which
are shown in FIG. 9. The decoder driver 3637 then receives the results of analysis
from the system target decoder 3622 and determines the decoding method for the
picture based on the results. Subsequently, the decoder driver 3637 indicates the
decoding method to the system target decoder 3622. The system target decoder 3622
begins to decode the picture according to the indicated decoding method. Details on
these processes are provided below.
[0231] «System Target Decoder»
[0232] FIG. 38 is a functional block diagram of the system target decoder 3622. As
shown in FIG. 38, the system target decoder 3622 includes a source depacketizer
3810, ATC counter 3820, first 27 MHz clock 3830, PID filter 3840, STC counter
(STC1) 3850, second 27 MHz clock 3860, primary video decoder 3870, secondary
video decoder 3871, PG decoder 3872, IG decoder 3873, primary audio decoder
3874, secondary audio decoder 3875, image processor 3880, primary video plane
memory 3890, secondary video plane memory 3891, PG plane memory 3892, IG
plane memory 3893, image plane memory 3894, and audio mixer 3895.
[0233] The source depacketizer 3810 reads source packets from the read buffer 3621,
extracts the TS packets from the read source packets, and transfers the TS packets to
the PID filter 3840. Furthermore, the source depacketizer 3810 synchronizes the
time of the transfer with the time shown by the ATS of each source packet.
Specifically, the source depacketizer 3810 first monitors the value of the ATC
generated by the ATC counter 3820. In this case, the value of the ATC depends on
the ATC counter 3820, and is incremented in accordance with a pulse of the clock
signal of the first 27 MHz clock 3830. Subsequently, at the instant the value of the
ATC matches the ATS of a source packet, the source depacketizer 3810 transfers the
TS packets extracted from the source packet to the PID filter 3840. By adjusting the
time of transfer in this way, the mean transfer rate Rjs of TS packets from the source
depacketizer 3810 to the PID filter 3840 does not surpass the system rate 2011
shown by the 2D clip information file in FIG. 20.
[0234] The PID filter 3840 first monitors a PID that includes each TS packet
outputted by the source depacketizer 3810. When the PID matches a PID
pre-specified by the playback control unit 3635, the PID filter 3840 selects the TS
packet and transfers it to the decoder 3870-3875 appropriate for decoding of the
elementary stream indicated by the PID. For example, if a PID is 0x1011, the TS
packets are transferred to the primary video decoder 3870, whereas TS packets with
PIDs ranging from 0x1B00-0x1B1F, 0x1100-0x111F, 0x1A00-0x1A1F,
0x1200-0x121F, and 0x1400-0x141F are transferred to the secondary video decoder
3871, the primary audio decoder 3874, the secondary audio decoder 3875, the PG
decoder 3872, and the IG decoder 3873, respectively.
[0235] The PID filter 3840 further detects a PCR from TS packets using the PIDs of
the TS packets. At each detection, the PID filter 3840 sets the value of the STC
counter 3850 to a predetermined value. Then, the value of the STC counter 3850 is
incremented in accordance with a pulse of the clock signal of the second 27 MHz
clock 3860. In addition, the value to which the STC counter 3850 is set is indicated
to the PID filter 3840 from the playback control unit 3635 in advance. The decoders
3870—3875 each use the value of the STC counter 3850 as the STC. That is, the
decoders 3870-3875 adjust the timing of decoding of the TS packets outputted from
the PID filter 3840 in accordance with the times indicated by the PTSs or the DTSs
included in the TS packets.
[0236] The primary video decoder 3870, as shown in FIG. 38, includes a transport
stream buffer (TB) 3801, multiplexing buffer (MB) 3802, elementary stream buffer
(EB) 3803, compressed video decoder (DEC) 3804, and decoded picture buffer
(DPB) 3805.
[0237] The TB 3801, MB 3802, and EB 3803 are each a buffer memory and use an
area of a memory element internally provided in the primary video decoder 3870.
Alternatively, some or all of the TB 3801, MB 3802, and EB 3803 may be separated
in discrete memory elements. The TB 3801 stores the TS packets received from the
PID filter 3840 as they are. The MB 3802 stores PES packets reconstructed from the
TS packets stored in the TB 3801. Note that when the TS packets are transferred
from the TB 3801 to the MB 3802, the TS header is removed from each TS packet.
The EB 3803 extracts encoded VAUs from the PES packets and stores the extracted,
encoded VAUs therein. A VAU includes a compressed picture, i.e., an I picture, B
picture, or P picture. Note that when data is transferred from the MB 3802 to the EB
3803, the PES header is removed from each PES packet.
[0238] The DEC 3804 is a hardware decoder specifically for decoding of
compressed pictures and is composed of an LSI that includes, in particular, a
function to accelerate the decoding. The DEC 3804 decodes a picture from each
VAU in the EB 3803 at the time shown by the DTS included in the original TS
packet. The DEC 3804 may also refer to the decoding switch information 1301
shown in FIG. 13 to decode pictures from VAUs sequentially, regardless of the
DTSs. The DEC 3804 performs decoding in the following order. First, the DEC
3804 analyzes a VAU header in response to an instruction from the decoder driver
3637. Next, the DEC 3804 transmits the analysis results to the decoder driver 3637.
Subsequently, upon receiving an instruction regarding the decoding method from the
decoder driver 3637, the DEC 3804 starts to decode a picture from the VAU via the
indicated method. Furthermore, the DEC 3804 transmits the decoded, uncompressed
picture to the DPB 3805. Details on each step are provided below.
[0239] Like the TB 3801, MB 3802, and EB 3803, the DPB 3805 is a buffer
memory that uses an area of a built-in memory element in the primary video decoder
3870. Alternatively, the DPB 3805 may be located in a memory element separate
from the other buffer memories 3801, 3802, and 3803. The DPB 3805 temporarily
stores the decoded pictures. When a P picture or B picture is to be decoded by the
DEC 3804, the DPB 3805 retrieves reference pictures, in response to an instruction
from the DEC 3804, from among stored, decoded pictures. The DPB 3805 then
provides the reference pictures to the DEC 3804. Furthermore, the DPB 3805 writes
each of the stored pictures into the primary video plane memory 3890 at the time
shown by the PTS included in the original TS packet.
[0240] The secondary video decoder 3871 includes the same structure as the primary
video decoder 3870. The secondary video decoder 3871 first decodes the TS packets
of the secondary video stream received from the PID filter 3840 into uncompressed
pictures. Subsequently, the secondary video decoder 3871 writes the uncompressed
pictures into the secondary video plane memory 3891 at the time shown by the PTSs
included in the TS packets.
[0241] The PG decoder 3872 decodes the TS packets received from the PID filter
3840 into uncompressed graphics data and writes the uncompressed graphics data to
the PG plane memory 3892 at the time shown by the PTSs included in the TS
packets.
[0242] The IG decoder 3873 decodes the TS packets received from the PID filter
3840 into uncompressed graphics data and writes the uncompressed graphics data to
the IG plane memory 3893 at the time shown by the PTSs included in the TS
packets.
[0243] The primary audio decoder 3874 first stores the TS packets received from the
PID filter 3840 in a buffer provided therein. Subsequently, the primary audio
decoder 3874 removes the TS header and the PES header from each TS packet in the
buffer, and decodes the remaining data into uncompressed LPCM audio data.
Furthermore, the primary audio decoder 3874 transmits the resultant audio data to
the audio mixer 3895 at the time shown by the PTS included in the TS packet. The
primary audio decoder 3874 selects the decoding method of the uncompressed audio
data in accordance with the compression encoding format, e.g. AC-3 or DTS, and
the stream attribute of the primary audio stream, which are included in the TS
packet.
[0244] The secondary audio decoder 3875 has the same structure as the primary
audio decoder 3874. The secondary audio decoder 3875 first decodes the TS packets
of the secondary audio stream received from the PID filter 3840 into uncompressed
LPCM audio data. Subsequently, the secondary audio decoder 3875 transmits the
uncompressed LPCM audio data to the audio mixer 3895 at the times shown by the
PTSs included in the TS packets. The secondary audio decoder 3875 changes
decoding schemes of uncompressed audio data depending on the compression
encoding format, e.g. Dolby Digital Plus or DTS-HD LBR, and the stream attribute
of the secondary audio stream included in the TS packets.
[0245] The audio mixer 3895 receives uncompressed audio data from both the
primary audio decoder 3874 and the secondary audio decoder 3875 and then mixes
the received data (i.e. synthesizes sounds). The audio mixer 3895 also transmits the
mixed audio data to, for example, an internal speaker 103 A of the display device
103.
[0246] The image processor 3880 receives graphics data, i.e., PNG or JPEG raster
data, along with the PTS thereof from the program execution unit 3634. Upon the
reception of the graphics data, the image processor 3880 renders the graphics data
and writes the graphics data to the image plane memory 3894.
[0247] «Collaboration Between the Decoder Driver and DEC in a 2D Playback
Device»
[0248] FIG. 39A is a schematic diagram showing the flow of data processed by the
decoder driver 3637 and DEC 3804 during decoding of the primary video stream. As
shown in FIG. 3 9A, processing to decode a single picture from the primary video
stream is mainly composed of the following five steps, A-E.
[0249] Step A (header analysis/output of a decode start command): the decoder
driver 3637 outputs a header analysis command, COMA, to the DEC 3804. The
header analysis command, COMA, includes information indicating the VAU in
which the next picture to be decoded is stored (for example, the AU identification
code 931A shown in FIG. 9). Furthermore, when the picture decoding method has
been determined in step E immediately before step A, the decoder driver 3637
outputs a decode start command, COMB, to the DEC 3804 along with the header
analysis command, COMA. The decode start command, COMB, includes
information indicating the decoding method determined in the immediately
preceding step E.
[0250] Step B (header analysis): the DEC 3804 performs the following processing in
response to the header analysis command, COMA. The DEC 3804 first retrieves the
VAU indicated by the header analysis command, COMA, from the EB 3803. Next,
the DEC 3804 reads the header HI in the VAU and analyzes the header HI. This
header HI includes the sequence header and the picture header, as well as the slice
headers in the compressed picture data, which are shown in FIG. 9. For example,
when the encoding method is MPEG-4 AVC, the header HI includes an SPS, PPS,
and slice header. In particular, the DEC 3804 retrieves the picture header by
referring to the identification number for the picture header (e.g. the identification
number of the PPS) included in the slice header, as shown by the arrow on the
dashed line in FIG. 9. The type of encoding method for the slice is thus acquired
from the picture header. Furthermore, the DEC 3804 retrieves the sequence header
by referring to the identification number for the video sequence (e.g. the
identification number of the SPS) indicated by the picture header, as shown by the
arrow on the alternating long and short dashed line in FIG. 9. The resolution, frame
rate, aspect ratio, and bit rate for the slice are thus acquired from the sequence
header. Based on the data acquired in this way, the DEC 3804 generates analysis
results for the header HI so as to contain information necessary to determine the
decoding method of the picture.
[0251] Step C (output of notification of completion): upon completing the header
analysis in step B, the DEC 3804 outputs a notification of completion RES to the
decoder driver 3637. This notification of completion RES includes the analysis
results for the header HI generated in step B.
[0252] Step D (determination of picture decoding method): in response to the
notification of completion RES, the decoder driver 3637 performs processing
preliminary to decoding of a picture. Specifically, the decoder driver 3637 refers to
the resolution, frame rate, aspect ratio, bit rate, type of encoding method, etc. in the
analysis results for the header HI indicated by the notification of completion RES
and, based on these factors, determines the picture decoding method.
[0253] Step E (picture decoding): the DEC 3804 performs the following processing
in response to the decode start command, COMB. The DEC 3804 first reads
compressed picture data from the VAU specified in the immediately preceding step
B. Next, the DEC 3804 decodes compressed picture data via the decoding method
indicated by the decode start command, COMB. Furthermore, the DEC 3804 stores
a decoded, uncompressed picture PIC in the DPB 3805. Afterwards, this
uncompressed picture PIC is written into the primary video plane memory 3890
from the DPB 3805.
[0254] FIG. 39B is a schematic diagram showing the flow of decoding in the
primary video stream. As shown in FIG. 39B, during successive processing, the
above five steps A-E are repeated as follows.
[0255] During the first step A, Al, the decoder driver 3637 outputs the first header
analysis command, COMA1, to the DEC 3804. The DEC 3804 performs the first
step B, B1 in response to the command COMAL That is, the DEC 3804 reads the
header HI in the VAU indicated by the command COMA1 from the EB 3803 and
analyzes the header HI. After this step B, Bl, the DEC 3804 performs the first step
C, C1. That is, the DEC 3804 outputs the first notification of completion RES1 to
the decoder driver 3637, thereby notifying the decoder driver 3637 of the analysis
results for the header HI. In response to the notification RES1, the decoder driver
3637 performs the first step D, Dl. That is, the decoder driver 3637 reads the
analysis results for the header HI from the notification RES1 and, based on the
analysis results, determines the picture decoding method. The decoder driver 3637
then performs the second step A, A2. That is, the decoder driver 3637 outputs the
second header analysis command, COMA2, and the first decode start command,
COMB1, to the DEC 3804. The DEC 3804 starts the first step E, El, in response to
the decode start command, COMB1. That is, the DEC 3804 uses the decoding
method indicated by the command COMB1 to decode a picture from the VAU
indicated by the first header analysis command, COMA1.
[0256] After the first step E, E1, the DEC 3804 performs the second step B, B2.
That is, the DEC 3804 reads the header HI in the VAU indicated by the second
header analysis command, COMA2, from the EB 3803 and analyzes the header HI.
After this step B, B2, the DEC 3804 performs the second step C, C2. That is, the
DEC 3804 outputs the second notification of completion RES2 to the decoder driver
3637, thereby notifying the decoder driver 3637 of the analysis results for the header
HI. In response to the notification RES2, the decoder driver 3637 performs the
second step D, D2. That is, the decoder driver 3637 reads the analysis results for the
header HI from the notification RES2 and, based on the analysis results, determines
the picture decoding method. The decoder driver 3637 then performs the third step
A, A3. That is, the decoder driver 3637 outputs the third header analysis command,
COMA3, and the second decode start command, COMB2, to the DEC 3804. The
DEC 3804 starts the second step E, E2 in response to the decode start command,
COMB2. That is, the DEC 3804 uses the decoding method indicated by the
command COMB2 to decode a picture from the VAU indicated by the second
header analysis command, COMA2.
[0257] The decoder driver 3637 and DEC 3804 similarly collaborate to decode the
third and subsequent pictures by repeating steps A-E.
[0258]
[0259] When playing back 3D video contents from a BD-ROM disc 101 in 3D
playback mode, the playback device 102 operates as a 3D playback device. The
fundamental part of the device's structure is identical to the 2D playback device
shown in FIGS. 36 to 39. Therefore, the following is a description of sections of the
structure of the 2D playback device that are enlarged or modified. Details on the
fundamental parts of the 3D playback device can be found in the above description
of the 2D playback device. Regarding the playback processing of 2D video images
in accordance with 2D playlist files, i.e. the playback processing of the 2D playlist,
the 3D playback device has the same structure as the 2D playback device.
Accordingly, the details on this structure can be found in the description of the 2D
playback device. The following description assumes playback processing of 3D
video images in accordance with 3D playlist files, i.e. 3D playlist playback
processing.
[0260] FIG. 40 is a functional block diagram of the 3D playback device 4000. The
3D playback device 4000 includes a BD-ROM drive 4001, playback unit 4002, and
control unit 4003. The playback unit 4002 includes a switch 4020, first read buffer
4021, second read buffer 4022, system target decoder 4023, and plane adder 4024.
The control unit 4003 includes a dynamic scenario memory 4031, static scenario
memory 4032, user event processing unit 4033, program execution unit 4034,
playback control unit 4035, player variable storage unit 4036, and decoder driver
4037. The playback unit 4002 and control unit 4003 are mounted on a different
integrated circuit, but may alternatively be mounted on a single integrated circuit. In
particular, the dynamic scenario memory 4031, static scenario memory 4032, user
event processing unit 4033, and program execution unit 4034 have an identical
structure with the 2D playback device shown in FIG. 36. Accordingly, details
thereof can be found in the above explanation of the 2D playback device.
[0261] The BD-ROM drive 4001 includes elements identical to the BD-ROM drive
3601 in the 2D playback device shown in FIG 36. When the playback control unit
4035 indicates a range of LBN, the BD-ROM drive 4001 reads data from the sector
group on the BD-ROM disc 101 indicated by the range. In particular, a source
packet group belonging to extents in the file SS, i.e. 3D extents, is transferred from
the BD-ROM drive 4001 to the switch 4020. In this case, each 3D extent includes
one or more pairs of a base-view and dependent-view data block, as shown in FIG.
24. These data blocks need to be transferred in parallel to different read buffers, i.e.
read buffers 4021 and 4022. Accordingly, the BD-ROM drive 4001 needs to have at
least the same access speed as the BD-ROM drive 3601 in the 2D playback device.
[0262] The switch 4020 receives 3D extents from the BD-ROM drive 4001. On the
other hand, the switch 4020 receives, from the playback control unit 4035,
information indicating the boundary in each data block included in the 3D extents.
This information indicates, for example, the number of source packets from the top
of the 3D extent to each boundary. In this case, the playback control unit 4035
generates this information by referring to the extent start points in the clip
information file. The switch 4020 further refers to this information to extract
base-view extents from each 3D extent, thereafter transmitting the extents to the first
read buffer 4021. Conversely, the switch 4020 transmits the remaining
dependent-view extents to the second read buffer 4022.
[0263] The first read buffer 4021 and the second read buffer 4022 are buffer
memories that use a memory element in the playback unit 4002. In particular,
different areas in a single memory element are used as the read buffers 4021 and
4022. Alternatively, different memory elements may be used as the read buffers
4021 and 4022. The first read buffer 4021 receives base-view extents from the
switch 4020 and stores these extents. The second read buffer 4022 receives
dependent-view extents from the switch 4020 and stores these extents.
[0264] First, the system target decoder 4023 alternately reads base-view extents
stored in the first read buffer 4021 and dependent-view extents stored in the second
read buffer 4022. Next, the system target decoder 4023 separates elementary streams
from each source packet via demultiplexing and furthermore, from the separated
streams, decodes the data shown by the PID indicated by the playback control unit
4035. The system target decoder 4023 then writes the decoded elementary streams
in internal plane memory according to the type thereof. The base-view video stream
is written in the left video plane memory, and the dependent-view video stream is
written in the right plane memory. On the other hand, the secondary video stream is
written in the secondary video plane memory, the IG stream in the IG plane memory,
and the PG stream in the PG plane memory. When stream data other than the video
stream is composed of a pair of base-view stream data and dependent-view stream
data, a pair of corresponding plane memories are prepared for the left-view plane
data and right-view plane data. The system target decoder 4023 also renders
graphics data from the program execution unit 4034, such as JPEG, PNG, etc. raster
data, and writes this data in the image plane memory.
[0265] The system target decoder 4023 associates the output of plane data from the
left-video and right-video plane memories with B-D presentation mode and B-B
presentation mode as follows. When the playback control unit 4035 indicates B-D
presentation mode, the system target decoder 4023 alternately outputs plane data
from the left-video and right-video plane memories. On the other hand, when the
playback control unit 4035 indicates B-B presentation mode, the system target
decoder 4023 outputs plane data from only the left-video or right-video plane
memory twice per frame while maintaining the operation mode in 3D playback
mode.
[0266] Furthermore, the system target decoder 4023 associates the output of
graphics plane data from the graphics plane memories with 2 plane mode, 1 plane
mode + offset mode, and 1 plane + zero offset mode as follows. The graphics plane
memories referred to here include the PG plane memory, IG plane memory, and
image plane memory. When the playback control unit 4035 indicates 2 plane mode,
the system target decoder 4023 alternately outputs left-view and right-view graphics
plane data from each of the graphics plane memories. When the playback control
unit 4035 indicates 1 plane + offset mode or 1 plane + zero offset mode, the system
target decoder 4023 outputs graphics plane data from each of the graphics plane
memories while maintaining the operation mode in 3D playback mode. When the
playback control unit 4035 indicates 1 plane + offset mode, the system target
decoder 4023 furthermore outputs the offset value designated by the playback
control unit 4035 to the plane adder 4024. On the other hand, when the playback
control unit 4035 indicates 1 plane + zero offset mode, the system target decoder
4023 outputs "0" as the offset value to the plane adder 4024.
[0267] Upon receiving a request from, for example, the program execution unit 4034
for performing 3D playlist playback processing, the playback control unit 4035 first
refers to the 3D playlist file stored in the static scenario memory 4032. Next, in
accordance with the 3D playlist file and following the sequence described with
regards to FIG. 33E, the playback control unit 4035 indicates to the BD-ROM drive
4001 the ranges of the LBN for the sector group on which the 3D extent to be read is
recorded. The playback control unit 4035 also refers to the extent start point in the
clip information file stored in the static scenario memory 4032 to generate
information indicating the boundaries of the data blocks included in each 3D extent.
The playback control unit 4035 transmits this information to the switch 4020.
[0268] Additionally, the playback control unit 4035 refers to the STN table and STN
table SS in the 3D playlist file to control the operation requirements of the system
target decoder 4023 and the plane adder 4024. For example, the playback control
unit 4035 selects the PID for the elementary stream to be played back and outputs
the PID to the system target decoder 4023. The playback control unit 4035 also
selects the presentation mode for each plane in accordance with the offset during
popup 3111 in the STN table SS and indicates these presentation modes to the
system target decoder 4023 and plane adder 4024.
[0269] As in the 2D playback device, the player variable storage unit 4036 includes
the SPRM shown in FIG. 37. However, any two of the SPRM(24)-(32) that were
reserved in FIG. 37 include the first flag and second flag shown in FIG. 35. For
example, the SPRM(24) may include the first flag, and the SPRM(25) the second
flag. In this case, when the SPRM(24) is "0", the playback device 102 only supports
playback of 2D video images, and when it is "1", the playback device 102 also
supports 3D video image playback. When the SPRM(25) is "0", the 3D video image
playback mode of the playback device 102 is L/R mode, and when it is "1", the 3D
video image playback mode is depth mode.
[0270] The plane adder 4024 receives each type of plane data from the system target
decoder 4023 and superimposes the pieces of plane data to create one composite
frame or field. In particular, in L/R mode, the left-video plane data represents the
left-view video plane, and the right-video plane data represents the right-view video
plane. Accordingly, from among the other pieces of plane data, the plane adder 4024
superimposes pieces that represent the left-view on the left-view plane data and
pieces that represent the right-view on the right-view plane data. On the other hand,
in depth mode, the right-video plane data represents a depth map for a video plane
representing the left-video plane data. Accordingly, the plane adder 4024 first
generates a pair of left-view video plane data and right-view video plane data from
both pieces of video plane data. Subsequently, the plane adder 4024 performs the
same composition processing as in L/R mode.
[0271] When receiving an indication of 1 plane + offset mode or 1 plane + zero
offset mode from the playback control unit 4035 as the presentation mode for the
secondary video plane, PG plane, IG plane, or image plane, the plane adder 4024
performs cropping processing on the plane data received from the system target
decoder 4023. A pair of left-view plane data and right-view plane data is thus
generated. In particular, when 1 plane + offset mode is indicated, the cropping
processing refers to the offset value indicated by the system target decoder 4023 or
the program execution unit 4034. On the other hand, when 1 plane + zero offset
mode is indicated, the offset value is set to "0" during cropping processing.
Accordingly, the same plane data is output repeatedly to represent the left-view and
right-view. Subsequently, the plane adder 4024 performs the same composition
processing as in L/R mode. The composited frame or field is output to the display
device 103 and displayed on the screen.
[0272] «System Target Decoder»
[0273] FIG. 41 is a functional block diagram of the system target decoder 4023. The
structural elements shown in FIG. 41 differ from the 2D playback device 3622
shown in FIG. 38 in the following two points: 1) the input channel from the read
buffer to each decoder is doubled, and 2) the main video decoder supports 3D
playback mode, and the secondary video decoder, PG decoder, and IG decoder
support 2 plane mode. That is, these video decoders can all alternately decode a
base-view stream and a dependent-view stream. On the other hand, the primary
audio decoder, secondary audio decoder, audio mixer, image processor, and plane
memories are similar to those in the 2D playback device shown in FIG. 38.
Accordingly, among the structural elements shown in FIG. 41, those differing from
the structural elements shown in FIG. 38 are described below, and details about
similar structural elements can be found in the description of FIG. 38. Furthermore,
since the video decoders each have a similar structure, only the structure of the
primary video decoder 4115 is described below. Similar descriptions are applicable
to the structure of other video decoders.
[0274] The first source depacketizer 4111 reads source packets from the first read
buffer 4021, retrieves TS packets included in the source packets, and transmits the
TS packets to the first PID filter 4113. The second source depacketizer 4112 reads
source packets from the second read buffer 4022, retrieves TS packets included in
the source packets, and transmits the TS packets to the second PID filter 4114.
Furthermore, each of the source depacketizers 4111 and 4112 synchronizes the time
of transferring the TS packets in accordance with the time shown by the ATS of
each source packet. This synchronization is made with the same method as the
source depacketizer 3810 shown in FIG. 38. Accordingly, a description thereof can
be found in the description provided for FIG. 38. With this sort of adjustment of
transfer time, the mean transfer rate RTS1 of TS packets from the first source
depacketizer 4111 to the first PID filter 4113 does not exceed the system rate 2011
indicated by the 2D clip information file shown in FIG. 20. Similarly, the mean
transfer rate Rts2 of TS packets from the second source depacketizer 4112 to the
second PID filter 4114 does not exceed the system rate indicated by the
dependent-view clip information file.
[0275] The first PID filter 4113 compares the PID of each TS packet received from
the first source depacketizer 4111 with the selected PID. The playback control unit
4035 designates the selected PID beforehand in accordance with the STN table in
the 3D playlist file. When the two PIDs match, the first PID filter 4113 transfers the
TS packets to the decoder assigned to the PID. For example, if a PID is 0x1011, the
TS packets are transferred to TB(1) 4101 in the primary video decoder 4115,
whereas TS packets with PIDs ranging from 0x1B00-0x1B1F, 0x1100-0x111F,
0x1A00-0x1A1F, 0x1200-0x121F, and 0x1400-0x141F are transferred to the
secondary video decoder, primary audio decoder, secondary audio decoder, PG
decoder, or IG decoder respectively.
[0276] The second PID filter 4114 compares the PID of each TS packet received
from the second source depacketizer 4112 with the selected PID. The playback
control unit 4035 designates the selected PID beforehand in accordance with the
STN table SS in the 3D playlist file. When the two PIDs match, the second PID
filter 4114 transfers the TS packet to the decoder assigned to the PID. For example,
if a PID is 0x1012 or 0x1013, the TS packets are transferred to TB(2) 4108 in the
primary video decoder 4115, whereas TS packets with PIDs ranging from
0x1B20-0x1B3F, 0x1220-0x127F, and 0x1420-0x147F are transferred to the
secondary video decoder, PG decoder, or IG decoder respectively.
[0277] The primary video decoder 4115 includes a TB(1) 4101, MB(1) 4102, EB(1)
4103, TB(2) 4108, MB(2) 4109, EB(2) 4110, buffer switch 4106, DEC 4104, DPB
4105, and picture switch 4107. The TB(1) 4101, MB(1) 4102, EB(1) 4103, TB(2)
4108, MB(2) 4109, EB(2) 4110 and DPB 4105 are all buffer memories, each of
which uses an area of the memory elements included in the primary video decoder
4115. Note that some or all of these buffer memories may be separated on different
memory elements.
[0278] The TB(1) 4101 receives TS packets that include a base-view video stream
from the first PID filter 4113 and stores the TS packets as they are. The MB(l) 4102
stores PES packets reconstructed from the TS packets stored in the TB(1) 4101. The
TS headers of the TS packets are removed at this point. The EB(1) 4103 extracts and
stores encoded VAUs from the PES packets stored in the MB(1) 4102. The PES
headers of the PES packets are removed at this point.
[0279] The TB(2) 4108 receives TS packets that include a dependent-view video
stream from the second PID filter 4114 and stores the TS packets as they are. The
MB(2) 4109 stores PES packets reconstructed from the TS packets stored in the
TB(2) 4108. The TS headers of the TS packets are removed at this point. The EB(2)
4110 extracts and stores encoded VAUs from the PES packets stored in the MB(2)
4109. The PES headers of the PES packets are removed at this point.
[0280] The buffer switch 4106 transfers the headers of the VAUs stored in the EB(1)
4103 and the EB(2) 4110 in response to a request from the DEC 4104. Furthermore,
the buffer switch 4106 transfers the compressed picture data for the VAUs to the
DEC 4104 at the times indicated by the DTSs included in the original TS packets. In
this case, the DTSs are equal between a pair of pictures belonging to the same 3D
VAU between the base-view video stream and dependent-view stream. Accordingly,
for a pair of VAUs that have the same DTS, the buffer switch 4106 first transmits
the VAU stored in the EB(1) 4103 to the DEC 4104. Additionally, the buffer switch
4106 may cause the DEC 4104 to return the decode switch information 1301 in the
VAU. In such a case, the buffer switch 4106 can determine if it should transfer the
next VAU from the EB(1) 4103 or the EB(2) 4110 by referring to the decode switch
information 1301.
[0281] Like the DEC 3804 shown in FIG. 38, the DEC 4104 is a hardware decoder
specifically for decoding of compressed pictures and is composed of an LSI that
includes, in particular, a function to accelerate the decoding. The DEC 4104 decodes
the compressed picture data transferred from the buffer switch 4106 in order. In
particular, the DEC 4104 performs such decoding with the following procedures.
The DEC 4104 first acquires the header for a VAU from the EB(1) 4103 and the
EB(2) 4110 in response to instructions from the decoder driver 4037. Next, the DEC
4104 analyzes the header and returns the results to the decoder driver 4037.
Afterwards, upon receiving an instruction regarding the decoding method from the
decoder driver 4037, the DEC 4104 starts to decode a picture from the VAU via the
decoding method. Furthermore, the DEC 4104 transfers the decoded, uncompressed
picture to the DPB 4105. Details on each procedure are provided below.
[0282] The DPB 4105 temporarily stores the decoded, uncompressed pictures. When
the DEC 4104 decodes a P picture or a B picture, the DPB 4105 retrieves reference
pictures from among the stored, uncompressed pictures in response to a request from
the DEC 4104 and supplies the retrieved reference pictures to the DEC 4104.
[0283] The picture switch 4107 writes the uncompressed pictures from the DPB
4105 to either the left-video plane memory 4120 or the right-video plane memory
4121 at the time indicated by the PTS included in the original TS packet. In this case,
the PTSs are equal between a base-view picture and a dependent-view picture
belonging to the same 3D VAU. Accordingly, for a pair of pictures that have the
same PTS and that are stored by the DPB 4105, the picture switch 4107 first writes
the base-view picture in the left-video plane memory 4120 and then writes the
dependent-view picture in the right-video plane memory 4121.
[0284] «Collaboration Between the Decoder Driver and DEC in a 3D Playback
Device»
[0285] FIG. 42A is a schematic diagram showing the flow of data processed by the
decoder driver 4037 and DEC 4104 during decoding of a pair of base-view and
dependent-view primary video streams. As shown in FIG. 42A, processing to
decode a pair of pictures from the pair of primary video streams includes the
following five steps, A-E.
[0286] Step A (header analysis/output of a decode start command): the decoder
driver 4037 outputs header analysis commands, BCOMA and DCOMA, to the DEC
4104. There are two types of header analysis commands: a base-view header
analysis command, BCOMA, and a dependent-view header analysis command,
DCOMA. The base-view header analysis command, BCOMA, includes information
indicating the VAU in which the next base-view picture to be decoded is stored. The
dependent-view header analysis command, DCOMA, includes information
indicating the VAU in which the next dependent-view picture to be decoded is
stored. Furthermore, when the picture decoding method has been determined in step
E immediately before step A, the decoder driver 4037 outputs decode start
commands, BCOMB and DCOMB, to the DEC 4104 along with the header analysis
commands, BCOMA and DCOMA. The decode start commands, BCOMB and
DCOMB, include information indicating the decoding method determined in the
immediately preceding step D. There are two types of decode start commands: a
base-view decode start command, BCOMB, and a dependent-view decode start
command, DCOMB. The base-view decode start command, BCOMB, includes
information indicating the decoding method of the base-view picture, and the
dependent-view decode start command, DCOMB, includes information indicating
the decoding method of the dependent-view picture.
[0287] Step B (header analysis): the DEC 4104 performs the following processing in
response to the header analysis commands, BCOMA and DCOMA. The DEC 4104
first requests the buffer switch 4106 to transmit the headers BHI and DHI for the
VAUs shown by the header analysis commands, BCOMA and DCOMA. The buffer
switch 4106 retrieves the headers BHI and DHI for the VAUs from the EB(1) 4103
and EB(2) 4110 in response to the request. In this case, the header BHI retrieved
from the EB(1) 4103 is included in the VAU for the base-view video stream.
Accordingly, this header BHI includes the sequence header and the picture header,
as well as the slice headers in the compressed picture data, which are shown in FIG.
9. On the other hand, the header DHI retrieved from the EB(2) 4110 is included in
the VAU for the dependent-view video stream. Accordingly, this header DHI
includes the sequence header and the picture header, as well as the slice headers in
the compressed picture data, which are shown in FIG. 9. Next, the DEC 4104
analyzes the headers BHI and DHI received from the buffer switch 4106. In
particular, the DEC 4104 retrieves the picture headers by referring to the
identification number for the picture header (e.g. the identification number of the
PPS) included in the slice headers, as shown by the arrows on the dashed lines in
FIG. 9. The types of encoding methods for the slices are thus acquired from the
picture headers. Furthermore, the DEC 4104 retrieves the sequence header and
sub-sequence header by referring to the identification number for the video sequence
(e.g. the identification number of the SPS) indicated by the picture headers, as
shown by the arrows on the alternating long and short dashed lines in FIG. 9. The
resolution, frame rate, aspect ratio, and bit rate for the slices are thus acquired from
the sequence header and the sub-sequence header. Based on the data acquired in this
way, the DEC 4104 generates analysis results for the header BHI and header DHI so
as to contain information necessary to determine the decoding method of the picture.
[0288] Step C (output of notification of completion): upon completing the header
analysis in step B, the DEC 4104 outputs a notification of completion, BRES or
DRES, to the decoder driver 4037. There are two types of notifications: a
notification of completion of base-view header analysis, BRES, and a notification of
completion of dependent-view header analysis, DRES. The notification of
completion of base-view header analysis, BRES, includes the analysis results for the
header BHI for the VAU that includes the next base-view picture to be decoded. The
notification of completion of dependent-view header analysis, DRES, includes the
analysis results for the header DHI for the VAU that includes the next
dependent-view picture to be decoded.
[0289] Step D (determination of picture decoding method): in response to each of
the notifications of completion, BRES and DRES, the decoder driver 4037 performs
processing preliminary to decoding of a picture. Specifically, the decoder driver
4037 refers to the resolution, frame rate, aspect ratio, bit rate, type of encoding
method, etc. in the analysis results for the header BHI and header DHI indicated by
the notifications of completion, BRES and DRES, and determines the picture
decoding methods based on these factors.
[0290] Step E (picture decoding): the DEC 4104 performs the following processing
in response to each of the decode start commands, BCOMB and DCOMB. The DEC
4104 first decodes compressed picture data, which has been transferred from the
buffer switch 4106, via the decoding method indicated by the decode start command,
BCOMB or DCOMB. Furthermore, the DEC 4104 stores a decoded, uncompressed
base-view picture BPIC and dependent-view picture DPIC in the DPB 4105.
Afterwards, the picture switch 4107 writes the uncompressed base-view picture
BPIC into the left video plane memory 4120 from the DPB 4105 and writes the
uncompressed dependent-view picture DPIC into the right video plane memory
4121 from the DPB 4105.
[0291] FIG. 42B is a schematic diagram showing the flow of decoding of the pair of
base-view and dependent-view primary video streams. As shown in FIG. 42B,
during successive processing, the above five steps A-E are repeated as follows.
[0292] During the first step A, Al, the decoder driver 4037 outputs the first
base-view header analysis command, BCOMA1, to the DEC 4104. The DEC 4104
performs the first step B, B1 in response to the command BCOMA1. That is, the
DEC 4104 first requests the buffer switch 4106 to transfer the header BHI for the
VAU indicated by the command BCOMA1. In response to this request, the buffer
switch 4106 retrieves the header BHI from the EB(1) 4103 and transfers it to the
DEC 4104. Next, the DEC 4104 analyzes the header BHI.
[0293] After this first step B, B1, the DEC 4104 performs the first step C, C1. That
is, the DEC 4104 outputs the first notification of completion of base-view header
analysis, BRES1, to the decoder driver 4037, thereby notifying the decoder driver
4037 of the analysis results for the header BHI. In response to the notification
BRES1, the decoder driver 4037 performs the first step D, D1. That is, the decoder
driver 4037 reads the analysis results for the BHI header from the notification
BRES1 and, based on the analysis results, determines the base-view picture
decoding method. At the start of the first step D, D1, the decoder driver 4037
performs the second step A, A2. That is, the decoder driver 4037 outputs the first
dependent-view header analysis command, DCOMA1, to the DEC 4104. The DEC
4104 performs the second step B, B2, in response to the command DCOMA1. That
is, the DEC 4104 first requests the buffer switch 4106 to transfer the header DHI for
the VAU indicated by the command DCOMA1. In response to this request, the
buffer switch 4106 retrieves the header DHI from the EB(2) 4110 and transfers it to
the DEC 4104. Next, the DEC 4104 analyzes the header DHI. Accordingly, step B,
B2, by the DEC 4104 proceeds in parallel with step D, D1, by the decoder driver
4037.
[0294] After the second step B, B2, the DEC 4104 performs the second step C, C2.
That is, the DEC 4104 outputs the first notification of completion of dependent-view
header analysis, DRES1, to the decoder driver 4037, thereby notifying the decoder
driver 4037 of the header DHI analysis results. In response to the notification
DRES1, the decoder driver 4037 performs the second step D, D2. That is, the
decoder driver 4037 reads the analysis results for the DHI header from the
notification DRES1 and, based on the analysis results, determines the
dependent-view picture decoding method. At the start of the second step D, D2, the
decoder driver 4037 performs the third step A, A3. That is, the decoder driver 4037
outputs the second base-view header analysis command, BCOMA2, and the first
base-view decode start command, BCOMB1, to the DEC 4104. The DEC 4104
starts the first step E, E1, in response to the base-view decode start command,
BCOMB1. That is, the DEC 4104 uses the decoding method indicated by the
command BCOMB1 to decode a base-view picture from the VAU indicated by the
first base-view header analysis command, BCOMA1. Accordingly, step E, El, by
the DEC 4104 proceeds in parallel with step D, D2, by the decoder driver 4037.
[0295] After the first step E, E1, the DEC 4104 performs the third step B, B3. That
is, the DEC 4104 first requests the buffer switch 4106 to transfer the header BHI for
the VAU indicated by the second base-view header analysis command, BCOMA2.
In response to this request, the buffer switch 4106 retrieves the header BHI from the
EB(1) 4103 and transfers it to the DEC 4104. Next, the DEC 4104 analyzes the
header BHI.
[0296] After the third step B, B3, the DEC 4104 performs the third step C, C3. That
is, the DEC 4104 outputs the second notification of completion of base-view header
analysis, BRES2, to the decoder driver 4037, thereby notifying the decoder driver
4037 of the header BHI analysis results. In response to the notification BRES2, the
decoder driver 4037 performs the third step D, D3. That is, the decoder driver 4037
reads the BHI header analysis results from the notification BRES2 and, based on the
analysis results, determines the base-view picture decoding method. At the start of
the third step D, D3, the decoder driver 4037 performs the fourth step A, A4. That is,
the decoder driver 4037 outputs the second dependent-view header analysis
command, DCOMA2 and the first dependent-view decode start command,
DCOMB1, to the DEC 4104. The DEC 4104 starts the second step E, E2, in
response to the decode start command, DCOMB1. That is, the DEC 4104 uses the
decoding method indicated by the decode start command, DCOMB1, to decode a
dependent-view picture from the VAU indicated by the first dependent-view header
analysis command, DCOMA1. Accordingly, step E, E2, by the DEC 4104 proceeds
in parallel with step D, D3, by the decoder driver 4037.
[0297] After the second step E, E2, the DEC 4104 performs the fourth step B, B4.
That is, the DEC 4104 first requests the buffer switch 4106 to transfer the header
DHI for the VAU indicated by the second dependent-view header analysis command,
DCOMA2. In response to this request, the buffer switch 4106 retrieves the header
DHI from the EB(2) 4110 and transfers it to the DEC 4104. Next, the DEC 4104
analyzes the header DHI.
[0298] After the fourth step B, B4, the DEC 4104 performs the fourth step C, C4.
That is, the DEC 4104 outputs the second notification of completion of
dependent-view header analysis, DRES2, to the decoder driver 4037, thereby
notifying the decoder driver 4037 of the header DHI analysis results. In response to
the notification DRES2, the decoder driver 4037 performs the fourth step D, D4.
That is, the decoder driver 4037 reads the analysis results for the DHI header from
the notification DRES2 and, based on the analysis results, determines the
dependent-view picture decoding method. At the start of the fourth step D, D4, the
decoder driver 4037 performs the fifth step A, A5. That is, the decoder driver 4037
outputs the third base-view header analysis command, BCOMA3, and the second
base-view decode start command, BCOMB2, to the DEC 4104. The DEC 4104
starts the third step E, E3, in response to the decode start command, BCOMB2. That
is, the DEC 4104 uses the decoding method indicated by the decode start command,
BCOMB2, to decode a base-view picture from the VAU indicated by the second
base-view header analysis command, BCOMA2. Accordingly, step E, E3, by the
DEC 4104 proceeds in parallel with step D, D4, by the decoder driver 4037.
[0299] Thereafter, the decoder driver 4037 and the DEC 4104 collaborate in the
above-described way, repeating steps A-E. In particular, step E by the DEC 4104
and step D by the decoder driver 4037 proceed in parallel. That is, while the decoder
driver 4037 is determining the decoding method of a base-view picture, the DEC
4104 decodes a dependent-view picture. Conversely, while the decoder driver 4037
is determining the decoding method of a dependent-view picture, the DEC 4104
decodes a base-view picture.
[0300] In the processing flow shown in FIG. 42B, even if completion of step D by
the decoder driver 4037 becomes delayed due to changes in the burden placed on the
control unit 4003 by other processing, there is no danger of step E by the DEC 4104
being delayed. In other words, in this processing flow there is no danger of an
excessively large interval between output of decoded pictures. For example, suppose
that instead of this processing flow, step B, B2, through step E, E2, for decoding of a
base-view picture take place after step B, B1, through step E, E1, for decoding of a
dependent-view picture are complete, as in the flow shown in FIG. 39B. In this case,
a decode start command, COMB1, is output in the next step A, A2, when
preprocessing in step D, D1, is complete, rather than when preprocessing starts.
Accordingly, if completion of the preprocessing is delayed, then output of the
decode start command, COMB1, is also delayed. This delays the start of decoding of
a dependent-view picture in the next step E, E2. As a result, there is a risk of the
time between the picture switch 4107 writing a base-view picture in the left video
plane memory 4120 and writing a dependent-view picture in the right video plane
memory 4121 becoming excessively long. By contrast, in the processing flow shown
in FIG. 42B, the second step D, D2, and the first step E, E1, for example, proceed in
parallel. Accordingly, even if completion of step D, D2, is delayed, as shown by the
alternating long and short dashed line in FIG. 42B, the start of step E, E1, is not
delayed. As a result, the picture switch 4107 can reliably maintain writing of a
base-view picture BPIC into the left video plane memory 4120 and of a
dependent-view picture DPIC into the right video plane memory 4121 in succession.
[0301] As described above, in the playback device 102 according to embodiment 1
of the present invention, while the DEC 4104 is decoding a picture, the decoder
driver 4037 determines the decoding method for the next picture. As a result, the
primary video decoder 4115 can reliably write pictures into the video planes 4120
and 4121 in succession. The playback device 102 can thus decode the video stream
more efficiently, which further increases reliability.
[0302] «Plane Adders»
[0303] FIG. 43 is a functional block diagram of the plane adder 4024. As shown in
FIG. 43, the plane adder 4024 includes a parallax video generation unit 4310, switch
4320, four cropping processing units 4331-4334, and four adders 4341-4344.
[0304] The parallax video generation unit 4310 receives left-video plane data 4301
and right-video plane data 4302 from the system target decoder 4023. In the
playback device 102 in L/R mode, the left-video plane data 4301 represents the
left-view video plane, and the right-video plane data 4302 represents the right-view
video plane. At this point, the parallax video generation unit 4310 transmits the
left-video plane data 4301 and the right-video plane data 4302 as they are to the
switch 4320. On the other hand, in the playback device 102 in depth mode, the
left-video plane data 4301 represents the video plane for 2D video images, and the
right-video plane data 4302 represents a depth map for the 2D video images. In this
case, the parallax video generation unit 4310 first calculates the binocular parallax
for each element in the 2D video images using the depth map. Next, the parallax
video generation unit 4310 processes the left-video plane data 4301 to shift the
presentation position of each element in the video plane for 2D video images to the
left or right according to the calculated binocular parallax. This generates a pair of
video planes representing the left-view and right-view. Furthermore, the parallax
video generation unit 4310 transmits the pair of video planes to the switch 4320 as a
pair of pieces of left-video and right-video plane data.
[0305] When the playback control unit 4035 indicates B-D presentation mode, the
switch 4320 transmits left-video plane data 4301 and right-video plane data 4302
with the same PTS to the first adder 4341 in that order. When the playback control
unit 4035 indicates B-B presentation mode, the switch 4320 transmits one of the
left-video plane data 4301 and right-video plane data 4302 with the same PTS twice
per frame to the first adder 4341, discarding the other piece of plane data.
[0306] The cropping processing units 4331-4334 include the same structure as a pair
of the parallax video generation unit 4310 and switch 4320. These structures are
used in 2 plane mode. In particular, in the playback device 102 in depth mode, the
parallax video generation unit located within each of the cropping processing units
4331-4334 converts the plane data from the system target decoder 4023 into a pair
of left-view and right-view pieces of plane data. When the playback control unit
4035 indicates B-D presentation mode, the left-view and right-view pieces of plane
data are alternately transmitted to each of the adders 4341-4344. On the other hand,
when the playback control unit 4035 indicates B-B presentation mode, one of the
left-view and right-view pieces of plane data is transmitted twice per frame to each
of the adders 4341-4344, and the other piece of plane data is discarded.
[0307] In 1 plane + offset mode, the first cropping processing unit 4331 receives an
offset value 4351 from the system target decoder 4023 and refers to this value to
perform cropping on the secondary video plane data 4303. The secondary video
plane data 4303 is thus converted into a pair of pieces of secondary video plane data
that represent a left-view and a right-view and are alternately transmitted. On the
other hand, in 1 plane + zero offset mode, the secondary video plane data 4303 is
transmitted twice. Similarly, the second cropping processing unit 4332 performs
cropping processing on the PG plane data 4304, and the third cropping processing
unit 4333 performs cropping processing on the IG plane data 4305.
[0308] FIGS. 44A and 44B are schematic diagrams showing cropping processing by
the second cropping processing unit 4332. As shown in FIGS. 44A and 44B, a pair
of left-view PG plane data 4404L and right-view PG plane data 4404R is generated
from one piece of PG plane data 4304 as follows. First, the second cropping
processing unit 4332 retrieves the offset value assigned to the PG plane from the
offset value 4351. Next, the second cropping processing unit 4332 shifts the
presentation position of each graphics video image indicated by the PG plane data
4304 by the offset value. This yields a left-view and right-view pair of pieces of PG
plane data 4404L and 4404R. Note that in 1 plane + zero offset mode, the offset
value is "0", and thus the original PG plane data 4304 is preserved as is. The first
cropping processing unit 4331 similarly processes the secondary video plane data
4303, and the third cropping processing unit 4333 similarly processes the IG plane
data 4305.
[0309] As shown in FIG. 44A, when the sign of the offset value indicates that the
depth of a 3D video image is closer than the screen, the second cropping processing
unit 4332 first shifts each piece of pixel data in the PG plane data 4304 from its
original position to the right by a number of pixels 4401L, which is the same as the
offset value. When the sign of the offset value indicates that the depth of a 3D video
image is deeper than the screen, the second cropping processing unit 4332 shifts
pixel data to the left. Next, the second cropping processing unit 4332 removes the
section of pixel data 4402L that protrudes outside the range of the PG plane data
4304 to the right (or left). The second cropping processing unit 4332 then outputs
the remaining pixel data 4404L as the left-view PG plane data.
[0310] As shown in FIG. 44B, when the sign of the offset value indicates that the
depth of a 3D video image is closer than the screen, the second cropping processing
unit 4332 first shifts each piece of pixel data in the PG plane data 4304 from its
original position to the left by a number of pixels 4401R, which is the same as the
offset value. When the sign of the offset value indicates that the depth of a 3D video
image is deeper than the screen, the second cropping processing unit 4332 shifts
pixel data to the right. Next, the second cropping processing unit 4332 removes the
section of pixel data 4402R that protrudes outside the range of the PG plane data
4304 to the left (or right). The second cropping processing unit 4332 then outputs
the remaining pixel data 4404R as the right-view PG plane data.
[0311] FIGS. 45A, 45B, and 45C are schematic diagrams respectively showing the
video images represented by the left-view and right-view PG plane data generated
by the cropping processing shown in FIG. 44, i.e. the left-view and right-view PG
planes, as well as the 3D video image perceived by a viewer based on these PG
planes. As shown in FIG. 45A, the left-view PG plane 4501L is shifted to the right
from the range of the screen 4502 by an offset value 4401L. As a result, the subtitle
2D video image 4503 in the left-view PG plane 4501L appears shifted to the right
from its original position by the offset value 4401L. As shown in FIG. 45B, the
right-view PG plane 4501R is shifted to the left from the range of the screen 4502 by
an offset value 4401R. As a result, the subtitle 2D video image 4503 in the
right-view PG plane 4501R appears shifted to the left from its original position by
the offset value 4401R. When these PG planes 4501L and 4501R are alternately
displayed on the screen 4502, then as shown in FIG. 45C, a viewer 4504 perceives
the subtitle 3D video image 4505 as closer than the screen 4502. The distance
between the 3D video image 4505 and the screen 4502 can be adjusted with the
offset values 4401L and 4401R. When the position of each piece of pixel data in the
PG plane data 4304 is shifted in the opposite direction than is shown in FIGS. 45A
and 45B, the viewer 4504 perceives the subtitle 3D video image 4505 to be further
back than the screen 4502.
[0312] In 1 plane + offset mode, cropping processing is thus used to generate a pair
of a left-view and right-view pieces of plane data from a single piece of plane data.
This allows a parallax video image to be displayed from just one piece of plane data.
In other words, a sense of depth can be given to a planar image. In particular, a
viewer can be made to perceive this planar image as closer or further back than the
screen. Note that in 1 plane + zero offset mode, the offset value is "0", and thus the
planar image is preserved as is.
[0313] Once again referring to FIG. 43, the image plane data 4306 is graphics data
transmitted from the program execution unit 4034 to the system target decoder 4023
and decoded by the system target decoder 4023. The graphics data is raster data such
as JPEG data or PNG data, and shows a GUI graphics component such as a menu.
The fourth cropping processing unit 4334 performs the cropping processing on the
image plane data 4306 as do the other cropping processing units 4331-4333.
However, unlike the other cropping processing units 4331-4333, the fourth cropping
processing unit 4334 receives the offset value from a program API 4352 instead of
from the system target decoder 4023. In this case, the program API 4352 is executed
by the program execution unit 4034. The offset value corresponding to the depth of
the image represented by the graphics data is thus calculated and output to the fourth
cropping processing unit 4334.
[0314] First, the first adder 4341 receives video plane data from the switch 4320 and
receives secondary plane data from the first cropping processing unit 4331. Next, the
first adder 4341 superimposes one set of video plane data and secondary plane data
at a time, outputting the result to the second adder 4342. The second adder 4342
receives PG plane data from the second cropping processing unit 4332,
superimposes the PG plane data on the plane data from the first adder 4341, and
outputs the result to the third adder 4343. The third adder 4343 receives IG plane
data from the third cropping processing unit 4333, superimposes the IG plane data
on the plane data from the second adder 4342, and outputs the result to the fourth
adder 4344. The fourth adder 4344 receives image plane data from the fourth
cropping processing unit 4334, superimposes the image plane data on the plane data
from the third adder 4343, and outputs the result to the display device 103. As a
result, the secondary plane data 4303, PG plane data 4304, IG plane data 4305, and
image plane data 4306 are superimposed on the left-video plane data 4301 and
right-video plane data 4302 in the order shown by the arrow 4300 in FIG. 43. Via
this composition processing, for each video image shown by plane data, the
left-video image plane or right-video image plane, secondary video plane, IG plane,
PG plane, and image plane appear to overlap in this order on the screen of the
display device 103.
[0315] In addition to the above-stated processing, the plane adder 4024 performs
processing to convert an output format of the plane data combined by the four
adders 4341-4344 into a format that complies with the 3D display method adopted
in a device such as the display device 103 to which the data is output. If an
alternate-frame sequencing method is adopted in the device, for example, the plane
adder 4024 outputs the composited plane data pieces as one frame or one field. On
the other hand, if a method that uses a lenticular lens is adopted in the device, the
plane adder 4024 composites a pair of left-view and right-view pieces of plane data
as one frame or one field of video data with use of built-in buffer memory.
Specifically, the plane adder 4024 temporarily stores and holds in the buffer
memory the left-view plane data that has been composited first. Subsequently, the
plane adder 4024 composites the right-view plane data, and further composites the
resultant data with the left-view plane data held in the buffer memory. During
composition, the left-view and right-view pieces of plane data are each divided, in a
vertical direction, into small rectangular areas that are long and thin, and the small
rectangular areas are arranged alternately in the horizontal direction in one frame or
one field so as to re-constitute the frame or the field. In this way, the pair of
left-view and right-view pieces of plane data is combined into one video frame or
field, which the plane adder 4024 then outputs to the corresponding device.
[0316]
[0317] [A] When the VAU 931 for the base-view video stream and the VAU 932 for
the dependent-view video stream shown in FIG. 9 belong to the same 3D VAU, the
sequence header 931B and sequence header 932B may match, the picture headers
931C and 932C may match, and the slice headers in the compressed picture data
931E and 932E may match. The same is true for the VAU 941 and 942 shown in
FIG. 10. In this case, during the processing to decode pictures shown in FIG. 42B,
the decoding method of the dependent-view picture should be set to the same
decoding method as the immediately preceding base-view picture. Accordingly, the
decoder driver 4037 can omit steps D pertaining to the dependent-view pictures, like
the second and fourth steps D, D2 and D4, shown in FIG. 42B. As a result, the
burden on the decoder driver 4037 for decoding processing can be even further
reduced.
[0318] [B] Reference to headers may be prohibited between the VAU for the
base-view video stream and the VAU for the dependent-view video stream shown in
FIGS. 9 and 10. FIG. 46 is a schematic diagram showing reference relationships
between headers of VAUs respectively found in a base-view video stream 4610 and
dependent-view video stream 4620. As shown in FIG. 46, in the base-view video
stream 4610, the top picture BPIC is divided into slices #1-#K (an integer K is
greater than or equal to 1) and stored in the compressed picture data 4601 for the
VAU. A slice header is attached to each of the slices #1-#K. Each slice header
includes the identification number for the picture header 4611 (for example, PPS
number) in the same VAU. As shown by the arrow on the dashed lines in FIG. 46,
the picture header 4611 to be referenced can thus be specified from the identification
number indicated by each slice header. Similarly, another picture is divided into
slices #1-#L (an integer L is greater than or equal to 1) and stored in the compressed
picture data 4602 of another VAU. The slice header attached to each of the slices
#1-#L includes the identification number for the picture header 4612 in the same
VAU. As shown by the arrow on the dashed lines in FIG. 46, the picture header
4612 to be referenced can thus be specified from the identification number indicated
by each slice header. Furthermore, the picture headers 4611 and 4612 include the
identification number (for example, SPS number) for the sequence header 4621 in
the same video sequence. As shown by the arrow on the alternating long and short
dashed line in FIG. 46, the sequence header 4621 to be referenced can thus be
specified from the identification number indicated by the picture headers 4611 and
4612.
[0319] Further referring to FIG. 46, in the dependent-view video stream 4620, the
top picture DPIC is similarly divided into slices #1-#K and stored in the compressed
picture data 4603 for the VAU. The slice header attached to each of the slices #1-#K
includes the identification number for the picture header 4613 in the same VAU. As
shown by the arrow on the dashed lines in FIG. 46, the picture header 4613 to be
referenced can thus be specified from the identification number indicated by each
slice header. Similarly, another picture is divided into slices #1-#L and stored in the
compressed picture data 4604 of another VAU. The slice header attached to each of
the slices #1-#L includes the identification number for the picture header 4614 in the
same VAU. As shown by the arrow on the dashed lines in FIG. 46, the picture
header 4614 to be referenced can thus be specified from the identification number
indicated by each slice header. Furthermore, the picture headers 4613 and 4614
include the number for the sub-sequence header 4622 in the same video sequence.
As shown by the arrow on the alternating long and short dashed line in FIG. 46, the
sub-sequence header 4622 to be referenced can thus be specified from the
identification number indicated by the picture headers 4613 and 4614.
[0320] As indicated by the arrows on the dashed lines with a cross in FIG. 46, in the
base-view video stream 4610, the slice headers are prohibited from including the
identification numbers for the picture headers 4613 and 4614 in the dependent-view
video stream 4620. Conversely, in the dependent-view video stream 4620, the slice
headers are prohibited from including the identification numbers for the picture
headers 4611 and 4612 in the base-view video stream 4610. Furthermore, as
indicated by the arrows on the alternating long and short dashed lines with a cross in
FIG. 46, in the base-view video stream 4610, the picture headers 4611 and 4612 are
prohibited from including the identification number for the sub-sequence header
4622 in the dependent-view video stream 4620. Conversely, in the dependent-view
video stream 4620, the picture headers 4613 and 4614 are prohibited from including
the identification number for the sequence header 4621 in the base-view video
stream 4610.
[0321] As shown in FIG. 46, when reference between headers in the base-view and
dependent-view video streams is prohibited, then in the steps B, B1-B4, and steps D,
D1-D4, shown in FIG. 42B, analysis of the headers in the base-view and
dependent-view video streams can be performed independently. Accordingly, both
the burden on the DEC 4104 in step B and the burden on the decoder driver 4037 in
step D can be reduced.
[0322] When reference between headers in the base-view and dependent-view video
streams is prohibited, then unlike the primary video decoder 4115 shown in FIG. 41,
each video decoder may include two DECs. FIG. 47 is a schematic diagram showing
the structure of the primary video decoder 4715 in such a case. In FIG. 47, elements
that are the same as those shown in FIG. 41 bear the same labels as in FIG. 41. In
FIG. 47, two DECs 4701 and 4702 are provided instead of the picture switch, unlike
in FIG. 41. Both of the DECs 4701 and 4702 are hardware decoders similar to the
DEC 3804 shown in FIG. 38. The DEC(l) 4701 decodes base-view pictures from
the VAUs in the EB(1) 4103. The DEC(2) 4702 decodes dependent-view pictures
from the VAUs in the EB(2) 4110. During decoding processing, the DEC(l) 4701
first analyzes the header of the VAU in response to a base-view header analysis
command, BCOMA, from the decoder driver 4037, returning the results to the
decoder driver 4037 via a notification of completion of base-view header analysis,
BRES. Furthermore, when receiving a base-view decode start command, BCOMB,
from the decoder driver 4037, the DEC(l) 4701 reads the decoding method from the
decode start command, BCOMB, and starts to decode a base-view picture via this
method. Similarly, the DEC(2) 4702 analyzes the header of the VAU in response to
a dependent-view header analysis command, DCOMA, from the decoder driver
4037, returning the results to the decoder driver 4037 via a notification of
completion of dependent-view header analysis, DRES. Furthermore, when receiving
a dependent-view decode start command, DCOMB, from the decoder driver 4037,
the DEC(2) 4702 reads the decoding method from the decode start command,
DCOMB, and starts to decode a dependent-view picture via this method.
[0323] The burden placed on the DECs 4701 and 4702 by decoding processing is
lighter than for the DEC 4104 shown in FIG. 41. Accordingly, the primary video
decoder 4715 shown in FIG. 47 increases reliability of decoding processing even
more than the primary video decoder 4115 shown in FIG. 41.
[0324] [C] Embodiment 1 of the present invention pertains to decoding technology
for a 3D video stream. However, the present invention can also be used in decoding
technology for high frame rate video. Specifically, the high frame rate video can for
example be divided into an odd-numbered frame group and an even-numbered frame
group, which can be considered as a base-view video stream and a dependent-view
video stream and recorded on a recording medium with the same data structure as
the data structure described in embodiment 1. A playback device that only supports
video playback at a normal frame rate can play back the odd-numbered frame group
from the recording medium. Conversely, a playback device that supports video
playback at a high frame rate can selectively play back only the odd-numbered
frame group or both frame groups. Compatibility with a playback device that only
supports video playback at a normal frame rate can thus be ensured on a recording
medium on which high frame rate video is stored.
[0325] [D] In embodiment 1 of the present invention, the base-view video stream
represents the left-view, and the dependent-view video stream represents the
right-view. Conversely, however, the base-view video stream may represent the
right-view and the dependent-view video stream the left-view.
[0326] [E] In an AV stream file for 3D video images, data related to the playback
format of 3D video images may be added to the PMT 1910 shown in FIG. 19. FIG.
48 is a schematic diagram showing the data structure of such a PMT 4810. As
shown in FIG. 48, this PMT 4810 includes 3D descriptors 4804 in addition to a
PMT header 4801, descriptors 4802, and pieces of stream information 4803. The
PMT header 4801 and the descriptors 4802 are the same as the PMT header 1901
and descriptors 1902 shown in FIG. 19. The 3D descriptors 4804 are information
that is related to the playback format of 3D video images and is common to the
entire AV stream file. In particular, the 3D descriptors 4804 include pieces of 3D
format information 4841. The pieces of 3D format information 4841 indicate the
playback format, such as L/R mode, depth mode, etc., for the AV stream file for 3D
video images.
[0327] Further referring to FIG. 48, each piece of stream information 4803 includes
a 3D stream descriptor 4834 in addition to a stream type 4831, PID 4832, and stream
descriptors 4833. The stream type 4831, PID 4832, and stream descriptors 4833 are
the same as the stream type 1931, PID 1932, and stream descriptors 1933 shown in
FIG. 19. The 3D stream descriptor 4834 indicates information related to the
playback format of 3D video images for each elementary stream included in an AV
stream file. In particular, the 3D stream descriptor 4834 for the video stream
includes 3D display types 4835. When the video images indicated by the video
stream are displayed in L/R mode, the 3D display types 4835 indicate whether the
video images are for the left-view or right-view. Also, when the video images
indicated by the video stream are displayed in depth mode, the 3D display types
4835 indicate whether the video images are 2D video images or depth maps.
[0328] As shown in FIG. 48, when the PMT 4810 includes information related to the
playback format of 3D video images, information on the playback system for the
video images can be acquired from only the AV stream file. Accordingly, this type
of data structure is helpful when distributing 3D video contents via broadcast waves,
for example.
[0329] [F] The offset table 2041 shown in FIG. 22A includes a table 2210 of offset
entries 2204 for each PID. The offset table may additionally include a table of offset
entries for each plane. In this case, analysis of the offset table by the 3D playback
device can be simplified. Furthermore, a lower limit, such as one second, may be
placed on the length of the valid section of an offset entry in conjunction with the
capabilities of the 3D playback device with regards to plane composition.
[0330] [G] The 3D playlist file shown in FIG. 30 includes one sub-path indicating
the playback path of the sub-TS. Alternatively, the 3D playlist file may include
sub-paths indicating playback paths for different sub-TSs. For example, the sub-path
type of one sub-path may be "3D L/R", and the sub-path type of another sub-path
may be "3D depth". When 3D video images are played back in accordance with this
3D playlist file, the playback device 102 can easily switch between L/R mode and
depth mode by switching the sub-path for playback between these two types of
sub-paths. In particular, this switching processing can be performed faster than
switching the 3D playlist file itself.
[0331] The 3D playlist file may include multiple sub-paths of the same sub-path
type. For example, when 3D video images for the same scene are represented with
different binocular parallaxes by using multiple right-views that share the same
left-view, a different file DEP is recorded on the BD-ROM disc 101 for each
different right-view video stream. The 3D playlist file then contains multiple
sub-paths with a sub-path type of "3D L/R". These sub-paths individually specify
the playback path for the different files DEP. Additionally, one file 2D may include
two or more types of depth map stream. In this case, the 3D playlist file includes
multiple sub-paths with a sub-path type of "3D depth". These sub-paths individually
specify the playback path for the files DEP that include the depth map streams.
When 3D video images are played back in accordance with such a 3D playlist file,
the sub-path for playback can quickly be switched, for example in response to user
operation, and thus the binocular parallax for 3D video images can be changed
without substantial delay. In this way, users can easily be allowed to select a desired
binocular parallax for 3D video images.
[0332] [H] In the data block group in the interleaved arrangement shown in FIG. 15,
for three types of data blocks with equal extent ATC times, such as the top three
data blocks D1, R1, and L1, the playback period may match, and the playback time
of the video stream may be equal. In other words, the number of VAUs and the
number of pictures in each of these data blocks may be equal. The significance of
such equality is explained below.
[0333] FIG. 49A is a schematic diagram showing the playback path when the extent
ATC times and the playback times of the video stream differ between contiguous
base-view data blocks and dependent-view data blocks. As shown in FIG. 49A, the
playback time of the top base-view data block B[0] is four seconds, and the
playback time of the top dependent-view data block D[0] is one second. In this case,
the section of the base-view data block that is necessary for decoding of the
dependent-view data block D[0] has the same playback time as the dependent-view
data block D[0]. Accordingly, to save read buffer capacity in the playback device
102, it is preferable, as shown by the arrow 4910 in FIG. 49A, to alternately read the
base-view data block B[0] and the dependent-view data block D[0] into the buffer
by the same amount of playback time, for example one second at a time. In that case,
however, as shown by the dashed lines in FIG. 49A, jumps occur during read
processing. As a result, it is difficult to cause read processing to keep up with
decoding processing, and thus it is difficult to stably maintain seamless playback.
[0334] FIG. 49B is a schematic diagram showing the playback path when the
playback times of the video stream are equal for contiguous base-view and
dependent-view data blocks. On a BD-ROM disc 101 according to embodiment 1 of
the present invention, as shown in FIG. 49B, the playback time of the video stream
between a pair of adjacent data blocks may be the same. For example, for the pair of
the top data blocks B[0] and D[0], the playback times of the video stream are both
equal to one second, and the playback times of the video stream for the second pair
of data blocks B[1] and D[1] are both equal to 0.7 seconds. In this case, during
playback of 3D video images, the playback device 102 reads data blocks B[0], D[0],
B[1], D[1] in order from the top, as shown by arrow 4920 in FIG. 49B. Simply in
this way, the playback device 102 can smoothly read the main TS and sub-TS
alternately. In particular, since no jump occurs during read processing, seamless
playback of 3D video images can be stably maintained.
[0335] If the extent ATC time is actually the same between contiguous base-view
and dependent-view data blocks, jumps do not occur during reading, and
synchronous decoding can be maintained. Accordingly, even if the playback period
or the playback time of the video stream are not equal, the playback device 102 can
reliably maintain seamless playback of 3D video images by simply reading data
block groups in order from the top, as in the case shown in FIG. 49B.
[0336] The number of any of the headers in a VAU, and the number of PES headers,
may be equal for contiguous base-view and dependent-view data blocks. These
headers are used to synchronize decoding between data blocks. Accordingly, if the
number of headers is equal between data blocks, it is relatively easy to maintain
synchronous decoding, even if the number of VAUs is not equal. Furthermore,
unlike when the number of VAUs is equal, all of the data in the VAUs need not be
multiplexed in the same data block. Therefore, there is a high degree of freedom for
multiplexing stream data during the authoring process of the BD-ROM disc 101.
[0337] The number of entry points may be equal for contiguous base-view and
dependent-view data blocks. FIG. 50 is a schematic diagram for such a case,
showing the relationships between entry points and a data block group in an
interleaved arrangement. As shown in FIG. 50, the 2D extents EXT1[n] (n = 0, 1,2,
...) in the file 2D 241 refer to base-view data blocks Ln, the right-view extents
EXT2[n] in the first file DEP 242 refer to right-view data blocks Rn, and the depth
map extents EXT3[n] in the second file DEP 243 refer to depth map data blocks Dn.
In FIG. 50, entry points are shown by triangles 5001, 5002, and 5003, and the
number of entry points included in each extent is indicated by a numeral. In the three
files 241, 242, and 243, the extents EXTl[n], EXT2[n], and EXT3[n], located in the
same order from the top, have the same number of entry points 5001, 5002, and
5003. When playing back 3D video images from a data block group Dn, Rn, and Ln,
a jump occurs in L/R mode at each depth map data block Dn, and a jump occurs in
depth mode at each right-view data block Rn. When the number of entry points is
equal between data blocks, however, the playback time is substantially equal.
Accordingly, it is easy to maintain synchronous decoding regardless of jumps.
Furthermore, unlike when the number of VAUs is equal, all of the data in the VAUs
need not be multiplexed in the same data block. Therefore, there is a high degree of
freedom for multiplexing stream data during the authoring process of the BD-ROM
disc 101.
[0338] [I] Conditions on Setting Sequence End Codes
[0339] As shown in FIG. 10, a VAU may include sequence end codes 941G and
942G. As described above, a sequence end code indicates the end of a video
sequence. When the video decoder in the playback device 102 detects a sequence
end code, it accordingly performs initialization processing, such as resetting the STC.
Therefore, by using a sequence end code, the video decoder can be caused to detect
a boundary of a video sequence from stream data for decoding without referring to a
playlist file.
[0340] FIGS. 51A-51F are schematic diagrams showing conditions on setting a
sequence end code for multiplexed stream data played back according to the main
path in the 2D playlist file. In FIG. 51, each rectangle AU represents one VAU in
the multiplexed stream data 5101 and 5102. In particular, sequence end codes are set
in the VAUs indicated by rectangles AU that are emphasized by diagonal lines.
[0341] In FIG. 51A, the connection condition (CC) is "1" for PI #2, which follows
PI #1. In this case, the video sequence differs between PI #1 and PI #2. In particular,
the playback end time PTS1 of PI #1 differs from the playback start time PTS2 of PI
#2. Accordingly, a sequence end code is set in the last VAU corresponding to the
playback end time PTS1 in the multiplexed stream data 5101 for playback indicated
by PI #1. Based on this sequence end code, the video decoder can detect that,
between the multiplexed stream data 5101 and 5102 to be played back, there is a
video sequence boundary.
[0342] In FIG. 5IB, the CC is "5" for PI #2, which follows PI #1. In this case, the
multiplexed stream data 5101 and 5102 to be played back indicated by PI #1 and PI
#2 is transmitted to the decoder successively. However, the video sequence differs
between PI #1 and PI #2. In particular, the playback end time PTS1 of PI #1 differs
from the playback start time PTS2 of PI #2. Accordingly, a sequence end code is set
in the last VAU corresponding to the playback end time PTS1 in the multiplexed
stream data 5101 for playback indicated by PI #1. Based on this sequence end code,
the video decoder can detect that, between the multiplexed stream data 5101 and
5102 to be played back, there is a video sequence boundary.
[0343] In FIG. 51C, the CC is "6" for PI #2, which follows PI #1. In this case, the
video sequence is continuous between PI #1 and PI #2. In particular, the playback
end time PTS1 of PI #1 equals the playback start time PTS2 of PI #2. Accordingly,
it is preferable not to cause the video decoder to detect the boundary between the
multiplexed stream data 5101 and 5102 to be played back indicated by PI #1 and PI
#2 as a video sequence boundary. Therefore, unlike FIGS. 51A and 51B, a sequence
end code is prohibited from being set in the last VAU corresponding to the playback
end time PTSl for PI#l.
[0344] In FIG. 5ID, the multiplexed stream data 5101 for playback indicated by PI
#1 includes video gaps G1 and G2. A "video gap" refers to locations where the
playback time of the video stream in the multiplexed stream data is interrupted.
Accordingly, in this multiplexed stream data 5101, a sequence end code is set in
each of the VAUs located immediately before the video gaps G1 and G2. The video
decoder can detect the video gaps G1 and G2 based on these sequence end codes. As
a result, the video decoder can avoid freezing during the video gaps G1 and G2, i.e.
"waiting for the next VAU to be transmitted". It is thus possible to prevent the
undesirable condition of "the video image represented by the data written into the
video plane immediately before each of the video gaps G1 and G2 being
continuously displayed".
[0345] In FIG. 51E, the multiplexed stream data 5101 for playback indicated by PI
#1 includes a discontinuous point in the STC sequence. An "STC sequence" refers
to a sequence of data with continuous PTSs. Accordingly, a "discontinuous point in
the STC sequence" refers to a location where the PTSs are not continuous. Such
discontinuous points include the case of updating the STC value in accordance with
the PCR. At the discontinuous point in the STC sequence shown in FIG. 51E, the
PTSs are not continuous between two contiguous VAUs. In this case, a sequence
end code is set in the earlier of the two VAUs. The video decoder can detect the
discontinuous point in the STC sequence based on this sequence end code.
[0346] In FIG. 51F, PI #N is located at the end of the main path 5103 in the 2D
playlist file. Accordingly, in the multiplexed stream data 5101 for playback
indicated by the PI #N, the VAU corresponding to the playback end time PTS1 is
located at the end of the video sequence. In this case, a sequence end code is set in
this VAU. The video decoder can detect the end of the video sequence based on this
sequence end code.
[0347] For cases other than the six cases shown in FIGS. 51A-51F, the playback
section is continuous. Accordingly, setting of a sequence end code in a VAU is
prohibited in the section of the multiplexed stream data corresponding to a
continuous playback section.
[0348] Conditions on setting sequence end codes are the same for multiplexed
stream data played back in accordance with the sub-path in the 2D playlist file. In
other words, in FIGS. 51A-51F, "PI" can be replaced by "SUB_PI", and
"connection condition" can be replaced by "SP connection condition".
[0349] Conditions on setting sequence end codes are the same for a main TS played
back in accordance with the main path and for a sub-TS played back in accordance
with the sub-path in the 3D playlist file. In particular, when a sequence end code is
set in either the VAU in the main TS or the VAU in the sub-TS belonging to the
same 3D VAU, a sequence end code also has to be set in the other VAU.
[0350] Note that for the setting of a stream end code, the condition that the stream
end code be "set only when a sequence end code is set, and placed immediately
thereafter" may be applied. Also, when the playback device can detect a video
sequence boundary from information other than a sequence end code, part or all of
the above condition may be waived in accordance with such detection ability. That
is, whether or not a sequence end code is actually set in the VAUs emphasized with
diagonal lines in FIGS. 51A-51F may be determined based on the playback device's
detection ability.
[0351] When the above-described conditions are set on sequence end codes for the
main TS and the sub-TS, the 3D playback device should be made not to detect a
sequence end code from a VAU in the base-view video stream via the following
method.
[0352] FIG. 52 is a schematic diagram showing the data structure of a TS packet
sequence storing a VAU #N in a base-view video stream for which a sequence end
code is set. As shown in FIG. 52, the VAU #N is generally divided into multiple
parts and stored in TS packets 5210 and 5220, after a PES header has been attached
to the top of the VAU #N. In the TS packets 5210 including the sequence end code
5201 and the stream end code 5202 in the VAU #N, the value of the TS degree of
priority 5211 is "1". Conversely, in the TS packets 5220 containing the rest of the
data in the VAU #N, the TS degree of priority 5221 is "0". These TS packets 5210
and 5220 are multiplexed in the base-view video stream. Note that the size of each
of the TS packets 5210 and 5220 is equally set to 188 bytes, using the AD fields
5212 and 5222 for stuffing as necessary. In the TS packets 5220, having a value of
"0" for the TS degree of priority 5221, padding data 5203 may be used for stuffing
instead of the AD field 5222.
[0353] FIG. 53 is a functional block diagram of a system target decoder 5310 in a
3D playback device. Unlike the system target decoder 4023 shown in FIG. 41, this
system target decoder 5310 includes a TS degree of priority filter 5301. Other
elements are the same for the system target decoders 5310 and 4023. Accordingly,
details on elements common to both decoders can be found in the description for the
system target decoder 4023 shown in FIG. 41.
[0354] The TS degree of priority filter 5301 monitors the value of the TS degree of
priority indicated by each TS packet transmitted from the first PID filter 4113 and,
based on this value, filters the TS packets. Specifically, the TS degree of priority
filter 5301 transmits TS packets having a TS degree of priority of "0" to the TB(1)
4101 and discards TS packets having a TS degree of priority of "1".
[0355] FIG. 54 is a schematic diagram showing the order of decoding, by the system
target decoder 5310 shown in FIG. 53, of a base-view video stream VAU 5401 and a
dependent-view video stream VAU 5402. The base-view video stream VAU 5401 is
the VAU #N shown in FIG. 52. The dependent-view video stream VAU 5402
belongs to the same 3D VAU as the VAU #N. As shown by the arrow 5403 in FIG.
54, processing by the system target decoder 5310 proceeds in order from the TS
packet included in the base-view video stream VAU 5401. As shown in FIG. 52, the
data from the top of the VAU 5401 until the padding data is stored in TS packets
5220 that have a TS degree of priority of "0". Accordingly, the TS degree of priority
filter 5301 stores these TS packets in the TB(1) 4101. On the other hand, the
sequence end code and stream end code in the VAU 5401 are stored in TS packets
5210 that have a TS degree of priority of "1". Accordingly, the TS degree of priority
filter 5301 discards these TS packets. As indicated by the cross in FIG. 54, decoding
of the sequence end code and the stream end code is thus skipped.
[0356] Via the above-described method, the sequence end code and the stream end
code in the base-view video stream VAU 5401 are not transferred to the primary
video decoder 4115. Accordingly, the primary video decoder 4115 does not detect a
sequence end code from the base-view video stream VAU 5401 before decoding the
dependent-view video stream VAU 5402. This avoids the risk of misinterpreting the
position of the sequence end code as a video sequence boundary, thus preventing a
playback error in the last 3D VAU due to an interruption in decoding.
[0357] Note that, unlike FIG. 52, the sequence end code and stream end code for a
base-view video stream VAU may be stored in TS packets with a TS degree of
priority of "0", and other data may be stored in TS packets with a TS degree of
priority of "1". In this case, the TS degree of priority filter 5301 discards TS packets
having a TS degree of priority of "0" and transmits TS packets having a TS degree
of priority of "1" to the TB(1) 4101. In the same way as shown in FIG. 54, the
primary video decoder 4115 can thus be prevented from detecting the sequence end
code in a base-view video stream VAU.
[0358] [J] Size of Data Blocks in the Interleaved Arrangement
[0359] On a BD-ROM disc 101 according to embodiment 1 of the present invention,
base-view and dependent-view data block groups are formed in the interleaved
arrangement shown in FIGS. 15 and 24. The interleaved arrangement is useful for
seamless playback of both 2D video images and 3D video images. To further ensure
such seamless playback, the size of each data block should meet the following
conditions based on the capability of the playback device 102.
[0360] [J-l] Conditions Based on Capability in 2D Playback Mode
[0361] FIG. 55 is a schematic diagram showing the playback processing system in
the playback device 102 in 2D playback mode. As shown in FIG. 55, this playback
processing system includes the BD-ROM drive 3601, read buffer 3621, and system
target decoder 3622 shown in FIG. 36. The BD-ROM drive 3601 reads 2D extents
from the BD-ROM disc 101 and transfers the 2D extents to the read buffer 3621 at a
read rate Rud-2D- The system target decoder 3622 reads source packets from each 2D
extent stored in the read buffer 3621 at a mean transfer rate ReXt2D and decodes the
source packets into video data VD and audio data AD.
[0362] The mean transfer rate ReXt2D is the same as 192/188 times the mean transfer
rate RTS of TS packets from the source depacketizer 3811 to the PID filter 3813
shown in FIG. 38. In general, this mean transfer rate ReXt2D changes for each 2D
extent. The maximum value Rmax2D of the mean transfer rate Rext2D is the same as
192/188 times the system rate for the file 2D. In this case, the 2D clip information
file specifies the system rate, as shown in FIG. 20. Also, the above coefficient
192/188 is the ratio of bytes in a source packet to bytes in a TS packet. The mean
transfer rate RexeD is conventionally represented in bits/second and specifically
equals the value of the size of a 2D extent expressed in bits divided by the extent
ATC time. The "size of an extent expressed in bits" is eight times the product of the
number of source packets in the extent and the number of bytes per source packet (=
192 bytes). The extent ATC time is the same as the time required to transfer all of
the source packets in the extent from the read buffer 3621 to the system target
decoder 3622.
[0363] In order to accurately calculate the extent ATC time when evaluating the
mean transfer rate, the size of each extent can be regulated as a fixed multiple of the
source packet length. Furthermore, when a particular extent includes more source
packets than this multiple, the extent ATC time of the extent can be calculated as
follows: first, the number of source packets exceeding the multiple is multiplied by
the transfer time per source packet (= 188 x 8 / system rate). This product is then
added to the extent ATC time corresponding to the fixed multiple to yield the extent
ATC time for the particular extent. Alternatively, the extent ATC time can be
defined as the sum of (i) the value of the time interval from the ATS of the top
source packet in an extent until the ATS of the last source packet in the same extent
and (ii) the transfer time per source packet. In this case, reference to the next extent
is unnecessary for calculation of the extent ATC time, and thus the calculation can
be simplified. Note that in the above-described calculation of extent ATC time, the
occurrence of wraparound in the ATS needs to be taken into consideration.
[0364] The read rate Rud-2d is conventionally expressed in bits/second and is set at a
higher value, e.g. 54 Mbps, than the maximum value Rmax2D of the mean transfer rate
Rext2D: Rud-2D > Rmax2D. This prevents underflow in the read buffer 3621 due to
decoding processing by the system target decoder 3622 while the BD-ROM drive
3601 is reading a 2D extent from the BD-ROM disc 101.
[0365] FIG. 56A is a graph showing the change in the data amount DA stored in the
read buffer 3621 during operation in 2D playback mode. FIG. 56B is a schematic
diagram showing the relationship between a data block group 5610 for playback and
a playback path 5620 in 2D playback mode. As shown in FIG. 56B, the data block
group 5610 is composed of a base-view data block group Ln (n = 0, 1,2, ...) and a
dependent-view data block group Dn, Rn in the interleaved arrangement. In
accordance with the playback path 5620, the base-view data blocks Ln are each
treated as one 2D extent EXT2D[n] and are read from the BD-ROM disc 101 into
the read buffer 3621. As shown in FIG. 5 6A, during the read period PR2o[n] for each
base-view data block Ln, i.e. each 2D extent EXT2D[n], the stored data amount DA
increases at a rate equal to Rud-2d - Rext2D[n], the difference between the read rate
Rud-2D and the mean transfer rate ReXt2D[n].
[0366] Reading and transfer operations by the BD-ROM drive 3601 are not actually
performed continuously, but rather intermittently, as shown in FIG. 56A. During the
read period PR2D[n] for each 2D extent, this prevents the stored data amount DA
from exceeding the capacity of the read buffer 3621, i.e. overflow in the read buffer
3621. Accordingly, the graph in FIG. 56A represents what is actually a step-wise
increase as an approximated straight increase.
[0367] A jump J2d[n], however, occurs between two contiguous 2D extents
EXT2D[n-l] and EXT2D[n]. Since the reading of two contiguous dependent-view
data blocks Dn and Rn is skipped during the corresponding jump period PJ2d[n],
reading of data from the BD-ROM disc 101 is interrupted. Accordingly, the stored
data amount DA decreases at a mean transfer rate Rextcd[n] during each jump period
PJ2D[n].
[0368] In order to play back 2D video images seamlessly from the data block group
5610 shown in FIG. 56B, the following conditions [1] and [2] should be met.
[0369] [1] While data is continuously provided from the read buffer 3621 to the
system target decoder 3622 during each jump period PJ2D[n], continual output from
the system target decoder 3622 needs to be ensured. To do so, the following
condition should be met: the size Sextd[n] of each 2D extent EXT2D[n] is the same
as the data amount transferred from the read buffer 3621 to the system target
decoder 3622 from the read period PR2D[n] through the next jump period PJ2D[n+1].
If this is the case, then as shown in FIG. 5 6A, the stored data amount DA at the end
of the jump period PJ2D[n+1] does not fall below the value at the start of the read
period PR2D[n]. In other words, during each jump period PJ2D[n], data is
continuously provided from the read buffer 3621 to the system target decoder 3622.
In particular, underflow does not occur in the read buffer 3621. In this case, the
length of the read period PR2D[n] equals Sext2D[n] / Rud-2D, the value obtained by
dividing the size Sext2D[n] of a 2D extent EXT2D[n] by the read rate Rud-2D-
Accordingly, the size Sext2D[n] of each 2D extent EXT2D[n] should satisfy
expression 1.
[0370]

[0371] In expression 1, the jump time Tjump-2D[n] represents the length of the jump
period PJ2D[n] in seconds. The read rate Rud-2D and the mean transfer rate Rext2d are
both expressed in bits per second. Accordingly, in expression 1, the mean transfer
rate ReXt2D is divided by 8 to convert the size Sext2D[n] of the 2D extent from bits to
bytes. That is, the size Sext2D[n] of the 2D extent is expressed in bytes. The function
CEIL() is an operation to round up fractional numbers after the decimal point of the
value in parentheses.
[0372] [2] Since the capacity of the read buffer 3621 is limited, the maximum value
of the jump period Tjump-2D[n] is limited. In other words, even if the stored data
amount DA immediately before a jump period PJ2d[n] is the maximum capacity of
the read buffer 3621, if the jump time Tjump.2D[n] is too long, the stored data amount
DA will reach zero during the jump period PJdM, and there is a danger of
underflow occurring in the read buffer 3621. Hereinafter, the time for the stored data
amount DA to decrease from the maximum capacity of the read buffer 3621 to zero
while data supply from the BD-ROM disc 101 to the read buffer 3621 has stopped,
that is, the maximum value of the jump time Tjump-2D that guarantees seamless
playback, is referred to as the "maximum jump time".
[0373] In standards of optical discs, the relationships between jump distances and
maximum jump times are determined from the access speed of the optical disc drive
and other factors. "Jump distance" refers to the length of the area on the optical disc
whose reading is skipped during a jump period. Jump distance is normally expressed
as the number of sectors of the corresponding section. FIG. 57 is an example of a
correspondence table between jump distances Sjump and maximum jump times
TjumP_max for a BD-ROM disc. As shown in FIG. 57, jump distances Sjump are
represented in units of sectors, and maximum jump times Tjump-max are represented in
milliseconds. In this figure, one sector equals 2048 bytes. When a jump distance
Sjump is zero sectors or is within a range of 1-10000 sectors, 10001-20000 sectors,
20001-40000 sectors, 40001 sectors-1/10 of a stroke, and 1/10 of a stroke or greater,
the corresponding maximum jump time Tjump_max is 50 ms, 250 ms, 300 ms, 350 ms,
700 ms, and 1400 ms, respectively.
[0374] When the jump distance Sjump is equal to zero sectors, the maximum jump
time is particularly referred to as a "zero sector transition time Tjump_0". A "zero
sector transition" is a movement of the optical pickup between two consecutive data
blocks. During a zero sector transition period, the optical pickup head temporarily
suspends its read operation and waits. The zero sector transition time may include,
in addition to the time for shifting the position of the optical pickup head via
revolution of the BD-ROM disc 101, overhead caused by error correction processing.
"Overhead caused by error correction processing" refers to excess time caused by
performing error correction processing twice using an ECC block when the
boundary for ECC blocks does not match the boundary for two data blocks. A whole
ECC block is necessary for error correction processing. Accordingly, when two
consecutive data blocks share a single ECC block, the whole ECC block is read and
used for error correction processing during reading of either data block. As a result,
each time one of these data blocks is read, a maximum of 32 sectors of excess data is
additionally read. The overhead caused by error correction processing is assessed as
the total time for reading the excess data, i.e. 32 sectors x 2048 bytes x 8 bits/byte x
2 instances / read rate RUd-2d. Note that by configuring each data block in ECC block
units, the overhead caused by error correction processing may be removed from the
zero sector transition time.
[0375] Based on the above considerations, the jump time Tjump-2d[n] to be substituted
into expression 1 is the maximum jump time specified for each jump distance by
BD-ROM disc standards. Specifically, the jump distance Sjump between the 2D
extents EXT2D[n-l] and EXT2D[n] is substituted into expression 1 as the jump time
TjumP-2D[n]. This jump distance Sjump equals the maximum jump time Tjump_max that
corresponds to the number of sectors from the end of the nth 2D extent EXT2D[n] to
the top of the (n+1)th 2D extent EXT2D[n+1] as found in the table in FIG. 57.
[0376] Since the jump time Tjump-2D[n] for the jump between two 2D extents
EXT2D[n] and EXT2D[n+1] is limited to the maximum jump time Tjump_max, the
jump distance Sjump, i.e. the distance between the two 2D extents EXT2D[n] and
EXT2D[n+1], is also limited. For example, when the maximum value Tjump_max, of
the jump time Tjump.2D[n] is limited to 700 ms, then the jump distance Sjump between
the two 2D extents EXT2D[n] and EXT2D[n+1] is permitted to be a maximum of
1/10 of a stroke (approximately 1.2 GB). When the jump time Tjump is at a maximum
jump time Tjump_max, the jump distance Sjump reaches this maximum value, which is
referred to as the "maximum jump distance Sjump_max". F°r seamless playback of 2D
video images, in addition to the size of 2D extents satisfying expression 1, the
distance between 2D extents needs to be equal to or less than the maximum jump
distance Sjump_max.
[0377] [J-2] «Conditions Based on Performance in 3D Playback Mode»
[0378] FIG. 58 is a schematic diagram showing the playback processing system in
the playback device 102 in 3D playback mode. As shown in FIG. 58, from among
the elements shown in FIG. 40, this playback processing system includes the
BD-ROM drive 4001, switch 4020, pair of read buffers 4021 and 4022, and system
target decoder 4023. The BD-ROM drive 4001 reads 3D extents from the BD-ROM
disc 101 and transfers the 3D extents to the switch 4020 at a read rate Rud-3D- The
switch 4020 separates 3D extents into base-view extents and dependent-view extents.
The base-view extents are stored in the first read buffer 4021, and the
dependent-view extents are stored in the second read buffer 4022. The stored data in
the second read buffer 4022 consists of right-view extents in L/R mode and of depth
map extents in depth mode. The system target decoder 4023 reads source packets
from the base-view extents stored in the first read buffer 4021 at a first mean transfer
rate ReXt1. The system target decoder 4023 in L/R mode reads source packets from
the right-view extents stored in the second read buffer 4022 at a second mean
transfer rate ReXt2. The system target decoder 4023 in depth mode reads source
packets from the depth map extents stored in the second read buffer 4022 at a third
mean transfer rate Rext3. The system target decoder 4023 also decodes pairs of read
base-view extents and dependent-view extents into video data VD and audio data
AD.
[0379] The first mean transfer rate Rext1 is referred to as the "base-view transfer rate".
The base-view transfer rate ReXt1 equals 192/188 times the mean transfer rate RTS1 of
TS packets from the first source depacketizer 4111 to the first PID filter 4113 shown
in FIG. 41. In general, this base-view transfer rate ReXt1 changes for each base-view
extent. The maximum value Rmax1 of the base-view transfer rate ReXt1 equals 192/188
times the system rate for the file 2D. The 2D clip information file specifies the
system rate. The base-view transfer rate ReXt1 is conventionally represented in
bits/second and specifically equals the value of the size of a base-view extent
expressed in bits divided by the extent ATC time. The extent ATC time equals the
time necessary to transfer all of the source packets in the base-view extent from the
first read buffer 4021 to the system target decoder 4023.
[0380] The second mean transfer rate ReXt2 is referred to as the "right-view transfer
rate", and the third mean transfer rate Rext3 is referred to as the "depth map transfer
rate". Both transfer rates ReXt2 and ReXt3 equal 192/188 times the mean transfer rate
R.TS2 of TS packets from the second source depacketizer 4112 to the second PID
filter 4114. In general, these transfer rates ReXt2 and Rext3 change for each
dependent-view extent. The maximum value Rmax2 of the right-view transfer rate
ReXt2 equals 192/188 times the system rate for the first file DEP, and the maximum
value Rmax3 of the depth map transfer rate ReXt3 equals 192/188 times the system rate
for the second file DEP. The right-view clip information file and depth map clip
information file specify the respective system rates. The transfer rates Rext2 and Rext3
are conventionally represented in bits/second and specifically equal the value of the
size of each dependent-view extent expressed in bits divided by the extent ATC time.
The extent ATC time equals the time necessary to transfer all of the source packets
in each dependent-view extent from the second read buffer 4022 to the system target
decoder 4023.
[0381] The read rate Rud_3D is conventionally expressed in bits/second and is set at a
higher value, e.g. 72 Mbps, than the maximum values Rmax1-Rmax3 of the first
through third mean transfer rates Rext1-Rext3: Rud-3D > Rmax1, Rud-3D > Rmaxi, Rud-3D >
Rmax3. This prevents underflow in the read buffers 4021 and 4022 due to decoding
processing by the system target decoder 4023 while the BD-ROM drive 4001 is
reading a 3D extent from the BD-ROM disc 101.
[0382] [L/R mode]
[0383] FIGS. 59A and 59B are graphs showing the change in data amounts DA1 and
DA2 stored in the read buffers 4021 and 4022 during operation in L/R mode. FIG.
59C is a schematic diagram showing the relationship between a data block group
5910 for playback and a playback path 5920 in L/R mode. As shown in FIG. 59C,
the data block group 5910 is composed of data block groups Dk, Rk, Lk (k = n-1, n,
n+1, n+2, ...) in the same interleaved arrangement as the data block group 5610
shown in FIG. 56B. In accordance with the playback path 5920, each pair of
adjacent right-view data blocks Rk and base-view data blocks Lk is read together as
one 3D extent EXTSS[k]. Subsequently, the switch 4020 separates the 3D extent
EXTSS[k] into a right-view extent and a left-view extent, which are stored in the
read buffers 4021 and 4022.
[0384] For sake of simplicity, this description does not differentiate between a
"base-view data block" and a "base view extent", nor between a "dependent-view
data block" and a "dependent-view extent". Furthermore, it is assumed that (n-1) 3D
extents have already been read, and that an integer n is sufficiently larger than one.
In this case, the stored data amounts DA1 and DA2 in the read buffers 4021 and
4022 are already maintained at or above the respective lower limits UL1 and UL2.
These lower limits UL1 and UL2 are referred to as a "buffer margin amount".
Details on the buffer margin amounts UL1 and UL2 are provided below.
[0385] As shown in FIGS. 59A and 59B, during the read period PRR[n] of the n*
right-view extent Rn, the stored data amount DA2 in the second read buffer 4022
increases at a rate equal to Rud-3D - RexsM, the difference between the read rate
Rud-3D and a right-view transfer rate Rexs[n], whereas the stored data amount DA1 in
the first read buffer 4021 decreases at a base-view transfer rate ReXtl[n-1]. As shown
in FIG. 59C, a zero sector transition J0[n] occurs between a contiguous right-view
extent Rn and base-view extent Ln. As shown in FIGS. 59A and 59B, during the
zero sector transition period PJ0[n], the stored data amount DA1 in the first read
buffer 4021 continues to decrease at the base-view transfer rate ReXt1[n-1], whereas
the stored data amount DA2 in the second read buffer 4022 decreases at the
right-view transfer rate Rext2[n]
[0386] As further shown in FIGS. 59A and 59B, during the read period PRL[n] for
the nth base-view extent block Ln, the stored data amount DA1 in the first read
buffer 4021 increases at a rate equal to Rud.3D - Rext1[n] the difference between the
read rate Rud-3D and a base-view transfer rate ReXtl[n], whereas the stored data
amount DA2 in the second read buffer 4022 continues to decrease at a right-view
transfer rate Rext2[n]. As further shown in FIG. 59C, a jump JLR[n] occurs between
the base-view extent Ln and the next right-view extent R(n+1). As shown in FIGS.
59A and 59B, during the jump period PJLR[n], the stored data amount DA1 in the
first read buffer 4021 decreases at the base-view transfer rate Rext1[n], and the stored
data amount DA2 in the second read buffer 4022 continues to decrease at the
right-view transfer rate Rex2[n].
[0387] For seamless playback of 3D video images in L/R mode from the data block
group 5910 shown in FIG. 59C, the following conditions [3], [4], and [5] should be
met.
[0388] [3] The size Sextl[n] of the nth base-view extent Ln is at least equal to the data
amount transferred from the first read buffer 4021 to the system target decoder 4023
from the corresponding read period PRJn] through the jump period PJlrM, the read
period PRR[n] of the next right-view extent R(n+1), and the zero sector transition
period PJ0[n+1]. In this case, at the end of this zero sector transition period PJ0[n+1],
the stored data amount DA1 in the first read buffer 4021 does not fall below the first
buffer margin amount UL1, as shown in FIG. 59A. The length of the read period
PRL[n] for the nth base-view extent Ln equals Sext1[n] / Rud-3D, the value obtained by
dividing the size Sext1[n] of this base-view extent Ln by the read rate Rud-3D. On the
other hand, the length of the read period PRR[n+1] for the (n+1)th right-view extent
R(n+1) equals Sext2[n+1] / Rud, the value obtained by dividing the size Sext2[n+1]
of the (n+1)th right-view extent R(n+1) by the read rate Rud-3d Accordingly, the size
Sext1[n] of this base-view extent Ln should satisfy expression 2.
[0389]

[0390] [4] The size Sext2[n] of the nth right-view extent Rn is at least equal to the data
amount transferred from the second read buffer 4022 to the system target decoder
4023 from the corresponding read period PRr[n] through the zero sector transition
period PJo[n], the read period PRL[n] of the next base-view extent Ln, and the jump
period PJLR[n]. In this case, at the end of this jump period PJlrM, the stored data
amount DA2 in the second read buffer 4022 does not fall below the second buffer
margin amount UL2, as shown in FIG. 59B. The length of the read period PRR[n]
for the nth right-view extent Rn equals Sext2[n]/ Rud-3D, the value obtained by
dividing the size Sext2[n] of this right-view extent Rn by the read rate Rud-3D-
Accordingly, the size Se^n] of this right-view extent Rn should satisfy expression
3.
[0391]

[0392] [5] The jump time Tjump3[n] to be substituted into expressions 2 and 3
equals the jump distance Sjump from the nth base-view extent Ln to the (n+1)th
right-view extent R(n+1). This jump distance Sjump equals the maximum jump
distance T^p^ that corresponds to the number of sectors from the end of the nth
base-view extent Ln to the top of the (n+1)* right-view extent R(n+1) as found in,
for example, the table in FIG. 57. Since the jump time T^^n] is thus limited to
the maximum jump time T^p^, the jump distance S^p is also limited to be equal
to or less than the maximum jump distance S^p^. In other words, for seamless
playback of 3D video images in L/R mode, in addition to the size of extents
satisfying expressions 2 and 3, the distance between the base-view extent Ln and the
right-view extent R(n+1) needs to be equal to or less than the maximum jump
distance Sjump_max.
[0393] [Depth Mode]
[0394] FIGS. 60A and 60B are graphs showing the change in data amounts DA1 and
DA2 stored in the read buffers 4021 and 4022 during operation in depth mode. FIG.
60C is a schematic diagram showing the relationship between a data block group
6010 for playback and a playback path 6020 in depth mode. As shown in FIG. 60C,
the data block group 6010 is composed of data block groups Dk, Rk, Lk in the same
interleaved arrangement as the data block group 5610 shown in FIG. 56C. In
accordance with the playback path 6020, depth map data blocks Dk and base-view
data blocks Lk are read as one 3D extent. As in FIG. 56, it is assumed that (n-1)
pairs of 3D extents have already been read, and that an integer n is sufficiently larger
than one. In this case, the stored data amounts DA1 and DA2 in the read buffers
4021 and 4022 are already maintained at or above the respective buffer margin
amounts UL1 and UL2.
[0395] As shown in FIGS. 60A and 60B, during the read period PRD[n] of the nth
depth map extent Dn, the stored data amount DA2 in the second read buffer 4022
increases at a rate equal to Rud-3D - Rext3[n], the difference between the read rate
Rud-3D and a depth map transfer rate ReXt3[n], and the stored data amount DA1 in the
first read buffer 4021 decreases at the base-view transfer rate ReXt1[n-1]. As shown in
FIG. 60C, a jump Jld[n] occurs from the depth map extent Dn until the base-view
extent Ln. As shown in FIGS. 60A and 60B, during the jump period PJldM, the
stored data amount DA1 in the first read buffer 4021 continues to decrease at the
base-view transfer rate Rext1[n-1], and the stored data amount DA2 in the second
read buffer 4022 decreases at the depth map transfer rate Rext3[n].
[0396] As further shown in FIGS. 60A and 60B, during the read period PRL[n] for
the nth base-view extent Ln, the stored data amount DA1 in the first read buffer 4021
increases at a rate equal to Rud-3D - Rext1 [n], the difference between the read rate
Rud-3D and the base-view transfer rate Rext1[n]. Conversely, the stored data amount
DA2 in the second read buffer 4022 continues to decrease at the depth map transfer
rate ReXt3[n]. As shown in FIG. 60C, a zero sector transition J0[n] occurs between a
contiguous left-view extent Ln and depth map extent D(n+1). As shown in FIGS.
60A and 60B, during the zero sector transition period PJo[n], the stored data amount
DA1 in the first read buffer 4021 decreases at the base-view transfer rate Rext[n],
and the stored data amount DA2 in the second read buffer 4022 continues to
decrease at the depth map transfer rate Rext3[n].
[0397] For seamless playback of 3D video images in depth mode from the data
block group 6010 shown in FIG. 60C, the following conditions [6], [7], and [8]
should be met.
[0398] [6] The size Sext1[n] of the nth base-view extent Ln is at least equal to the data
amount transferred from the first read buffer 4021 to the system target decoder 4023
from the corresponding read period PRl[n] through the zero sector transition period
PJ0[n], the read period PRD[n] of the next depth map extent D(n+1), and the jump
period PJLD[n+1]. In this case, at the end of this jump period PJLD[n+1], the stored
data amount DA1 in the first read buffer 4021 does not fall below the first buffer
margin amount UL1, as shown in FIG. 60 A. The length of the read period PRL[n]
for the nth base-view extent Ln equals Sext1[n] / Rud-3d, the value obtained by dividing
the size Sext1[n] of this base-view extent Ln by the read rate Rud-3D. On the other hand,
the length of the read period PRD[n+1] for the (n+1)th depth map extent D(n+1)
equals Sext3[n+1] / Rud-3d, the value obtained by dividing the size Sext3[n+1] of the
(n+1)th depth map extent D(n+1) by the read rate Rud-3D- Accordingly, the size
Sext1[n] of this base-view extent Ln should satisfy expression 4.
[0399]

[0400] [7] The size Sext3[n] of the nth depth map extent Dn is at least equal to the data
amount transferred from the second read buffer 4022 to the system target decoder
4023 from the corresponding read period PRD[n] through the jump period PJld[n],
the read period PRl[n] of the next base-view extent Ln, and the zero sector transition
period PJo[n]. In this case, at the end of this zero sector transition period PJo[n], the
stored data amount DA2 in the second read buffer 4022 does not fall below the
second buffer margin amount UL2, as shown in FIG. 60B. The length of the read
period PRD[n] for the nth depth map extent Dn equals Sext3[n] / Rud-3D, the value
obtained by dividing the size Sext3[n] of this depth map extent Dn by the read rate
Rud-3d- Accordingly, the size Sext3[n] of this depth map extent Dn should satisfy
expression 5.
[0401]
[0402] [8] The jump time Tjump-3D[n] to be substituted into expressions 4 and 5
equals the jump distance Sjump from the nth depth map extent Dn to the nth base-view
extent Ln. This jump distance Sjump equals the maximum jump distance Tjump_max that
corresponds to the number of sectors from the end of the nth depth map extent Dn to
the top of the nth base-view extent Ln as found in, for example, the table in FIG. 57.
Since the jump time Tjump-3D[n] is thus limited to the maximum jump time Tjump_max,
the jump distance Sjump is also limited to be equal to or less than the maximum jump
distance Sjump_max. In other words, for seamless playback of 3D video images in
depth mode, in addition to the size of extents satisfying expressions 4 and 5, the
distance between the depth map extent Dn and the base-view extent Ln needs to be
equal to or less than the maximum jump distance Sjump_max.
[0403] Based on the above results, in order to permit seamless playback of 2D video
images, of 3D video images in L/R mode, and of 3D video images in depth mode
from data block groups in the interleaved arrangement, the size of each data block
should be designed to satisfy all of the above expressions 1-5. In particular, the size
of the base-view data block should be equal to or greater than the largest value
among the right-hand side of expressions 1,3, and 5. Hereinafter, the lower limit on
the size of a data block that satisfies all of the expressions 1-5 is referred to as the
"minimum extent size".
[0404] [J-3] Conditional Expressions for Data Block Groups Corresponding to L/R
Mode Only
[0405] When only L/R mode is used for playback of 3D video images, the depth
map data blocks in the arrangement in FIG. 56 may be removed. In other words, two
types of data blocks, base-view data blocks B[n] (n = 0, 1, 2, ...) and
dependent-view data blocks D[n], may be recorded on the BD-ROM disc in the
interleaved arrangement shown in FIG. 24. Conditions are similarly placed on this
arrangement for the size of data blocks necessary for seamless playback of video
images.
[0406] As shown in FIG. 24, during playback of 2D video images, only the 2D
extents EXT2D[n] in file 2D 2410, i.e. the base-view data blocks B[n], are read,
whereas reading of the dependent-view data blocks D[n] is skipped by jumps. The
playback path for 2D video images differs from the playback path 5620 shown in
FIG. 56 only by the jump distances. Accordingly, for seamless playback of 2D video
images, the size Sext1[n] of the nth 2D extent EXT2D[n] should fulfill expression 1.
[0407] During playback of 3D video images, 3D extents EXTSS[n] are read from
file SS 2420 and divided into base-view extents EXT1[n] and dependent-view
extents EXT2[n]. In this case, the playback path for 3D video images differs from
the playback path 5920 for 3D video images in L/R mode shown in FIG. 59 in that
only zero sector transitions occur, whereas jumps do not occur. Accordingly, for
seamless playback of 3D video images, the following condition should be met: the
size Sext1[n] of the nth base-view extent EXT1[n], i.e. the base-view data block B[n],
should fulfill expression 6 below instead of expression 2. On the other hand, the size
Sext2[n] of the nth dependent-view extent EXT2[n], i.e. the dependent-view data
block D[n], should fulfill expression 7 below instead of expression 3. Expressions 6
and 7 are the same as expressions 2 and 3, replacing the jump time Tjump-3D with the
zero sector transition time Tjump-0.
[0408]

[0409] Accordingly, the size of the base-view data block B[n] should fulfill
expressions 1 and 6. Note that during reading of a 3D extent EXTSS[n], the zero
sector transition time Tjump_0[n] may be considered to be 0. In this case, expressions 6
and 7 change into the following expressions.
[0410]

[0411] [K] The playback device 102 in 3D playback mode may use a single read
buffer instead of the two read buffers 4021 and 4022 shown in FIG. 40.
[0412] FIG. 61 is a schematic diagram showing a playback processing system when
the playback device 102 in 3D playback mode uses a single read buffer. As shown in
FIG. 61, this playback processing system differs from the system shown in FIG. 58
by including a single read buffer 6101 instead of a switch 4020 and a pair of read
buffers 4021 and 4022. The BD-ROM drive 4001 reads 3D extents from the
BD-ROM drive 101 and transmits them to the read buffer 6101. The read buffer
6101 stores data for the 3D extents in the order they are transferred. The system
target decoder 4023 receives information from the playback control unit 4035
indicating the boundary of each data block included in the 3D extent. Furthermore,
the system target decoder 4023 uses this information to detect the boundary between
data blocks from the 3D extents stored in the read buffer 6101. The system target
decoder 4023 can thus identify regions in the read buffer 6101 in which base-view
extents and dependent-view extents are stored. Furthermore, the system target
decoder 4023 transmits source packets from the extents stored in each area in the
read buffer 6101 to one of two source packetizers 4111 and 4112. The source
packetizer 4111 or 4112 to which source packets are transmitted is selected in
accordance with the type of extent stored in the area in the read buffer 6101 from
which source packets are transmitted. Furthermore, the system target decoder 4023
reads source packets from the read buffer 6101 at a mean transfer rate equal to the
sum of the base-view transfer rate and the right-view transfer rate (or the depth map
transfer rate).
[0413] FIGS. 62A and 62B are schematic diagrams showing changes in the area in
which data is stored in the read buffer 6101 when a data block group 6210 in the
interleaved arrangement is read in accordance with a playback path 6220.
[0414] At the first point in time PA on the playback path 6220, the top right-view
extent EXT2[0] is stored in order from the top of the read buffer 6101. The system
target decoder 4023 waits to start reading source packets from the read buffer 6101
until the playback path 6220 progresses until the second point in time PB, when the
top right-view extent EXT2[0] is entirely stored in the read buffer 6101.
[0415] At the second point in time PB, the system target decoder 4023 detects the
boundary between the top right-view extent EXT2[0] and the top base-view extent
EXT1[0] in the read buffer 6101 and distinguishes between the areas in which these
extents are stored. Furthermore, the system target decoder 4023 starts to transmit
source packets from the read buffer 6101.
[0416] At the third point in time PC on the playback path 6220, the right-view extent
EXT2[0] stored in the read buffer 6101 is read in order from the top of the read
buffer 6101. On the other hand, the top base-view extent EXT1[0] is stored in the
next area after the area in which the right-view extent EXT2[0] is stored and is read
in order from the part that was stored first.
[0417] At the fourth point in time PD on the playback path 6220, the top base-view
extent EXT1[0] has been completely stored in the read buffer 6101. After the point
in time when data is stored at the end of the read buffer 6101, subsequent data is
stored at the top of the read buffer 6101. This area is made available by the top
right-view extent EXT2[0] being read. Accordingly, the top base-view extent
EXT1[0] is divided into two parts S11 and S12 and stored in the read buffer 6101.
Furthermore, at the fourth point in time PD, the system target decoder 4023 detects
the boundary between the top base-view extent EXT1[0] and the second right-view
extent EXT2[1] in the read buffer 6101 and distinguishes between the areas in which
these extents are stored.
[0418] At the fifth point in time PE on the playback path 6220, the second
right-view extent EXT2[1] is stored in the next area after the area in which the top
right-view extent EXT2[0] is stored.
[0419] At the sixth point in time PF on the playback path 6220, the second
right-view extent EXT2[1] is read in the order in which it was stored. Meanwhile,
the second base-view extent EXT1[1] is stored in the next area after the area in
which the top base-view extent EXT1[0] is stored. Furthermore, this area extends up
to the area made available by the second right-view extent EXT2[1] being read.
[0420] As shown in FIG. 62B, by using the available area in the read buffer 6101,
base-view extents EXT1[n] and right-view extents EXT2[n] can be stored
alternately even in a single read buffer 6101. Furthermore, in this case, the capacity
RB0 necessary in the read buffer 6101 can be reduced below the total capacity of the
pair of read buffers 4021 and 4022 shown in FIG. 41.
[0421] FIG. 63B is a schematic diagram showing the playback path 6320 in L/R
mode for a data block group 6310 in the interleaved arrangement. FIG. 63A is a
graph showing changes in the data amount DA stored in the read buffers 6101, 4021,
and 4022 when the playback processing systems in FIGS. 58 and 61 read the data
block group 6310 according to the playback path 6320. In FIG. 63A, the solid line
GRO shows the changes in the stored data amount in the read buffer 6101, the
alternating long and short dashed line GR1 shows the changes in the stored data
amount in the first read buffer 4021, and the dashed line GR2 shows the changes in
the stored data amount in the second read buffer 4022. As FIG. 62A illustrates, the
stored data amount in the read buffer 6101 equals the total of the stored data
amounts in the pair of read buffers 4021 and 4022. On the other hand, as shown in
FIG. 63 A, in the lines GR1 and GR2 for the stored data amounts in the pair of read
buffers 4021 and 4022, the peaks of one line are closer to the other line's minimum
points than to the other line's peaks. Accordingly, all of the peaks in the line GRO
for the stored data amount in the read buffer 6101 are well below the sum RB1+RB2
of the capacities of the pair of read buffers 4021 and 4022. Therefore, the capacity
RB0 of the read buffer 6101 can be reduced below the sum RB1+RB2 of the
capacities of the pair of read buffers 4021 and 4022.
[0422] In the playback processing system shown in FIG. 61, as in the system shown
in FIG. 58, the timing of transmission of source packets from the read buffer 6101 to
the system target decoder 4023 is adjusted in accordance with the ATS assigned to
the source packets. Accordingly, when a base-view extent EXT1[n] and a
dependent-view extent EXT2[n] stored in the read buffer 6101 include source
packets with the same ATS, they cannot be transmitted from the read buffer 6101 to
the system target decoder 4023 simultaneously. For example, if the extents EXT1[n]
and EXT2[n] both include source packets with ATS = 100, the transmission time of
one of the source packets will be delayed past the time indicated by ATS = 100 by
the transmission time for one source packet. As a result, there is a risk of problems
occurring, such as buffer underflow. This risk can be avoided, however, by setting
ATSs for the base-view and dependent-view as follows.
[0423] FIG. 64 is a schematic diagram showing settings of such ATSs. In FIG. 64,
rectangles 6410 indicating source packets SP#10, SP#11, SP#12, and SP#13 for
base-view extents and rectangles 6420 indicating source packets SP#20, SP#21,
SP#22, and SP#23 for dependent-view extents are arranged along the ATC time axis
in order of the ATS for each source packet. The position of the top of each rectangle
6410 and 6420 represents the value of the ATS for that source packet. On the other
hand, the length of each rectangle 6410 and 6420 represents the amount of time
necessary to transfer one source packet from the read buffer 6101 to the system
target decoder 4023 in the playback processing system in the 3D playback device
shown in FIG. 61. Hereinafter, this time is referred to as the first time ATI.
Conversely, the amount of time necessary to transfer one source packet from the
read buffer 3621 to the system target decoder 3622 in the playback processing
system in the 2D playback device shown in FIG. 55 is referred to as the second time
AT2.
[0424] As shown in FIG. 64, in base-view extents, the interval between ATSs for
contiguous source packets is set to at least AT2. For example, the ATS for SP#11 is
prohibited from being set before the second time AT2 has passed after the ATS of
SP#10. With this setting, the system target decoder 3622 in the 2D playback device
can completely transmit the entire SP#10 from the read buffer 3621 in the time
period from the ATS of SP#10 to the ATS of SP#11. Accordingly, the system target
decoder 3622 can start transmitting SP#11 from the read buffer 3621 at the time
indicated by the ATS of SP#11.
[0425] Furthermore, the time period from the ATS of each dependent-view extent
source packet SP#20, SP#21, ... through the first time AT1 thereafter is not allowed
to overlap the time period from the ATS of each base-view extent source packet
SP#10, SP#11, ... through the first time AT1 thereafter. In other words, in FIG. 64,
the time periods of the ATCs corresponding to the lengthwise ranges of the
rectangles 6420 that represent the source packets SP#20, SP#21, ... are not allowed
to overlap the time periods of the ATCs corresponding to the lengthwise ranges of
the rectangles 6410 that represent the source packets SP#10, SP#11, .... For
example, the interval between the ATS of SP#22 and the ATS of SP#13 is
prohibited from being set shorter than the first time ATI. With this setting, the
system target decoder 4023 in the 3D playback device can transmit SP#22 and
SP#13 from the read buffer 6101 during different time periods. Two source packets
to which the same ATS has been assigned can thus be prevented from being
transmitted simultaneously from the read buffer 6101 to the system target decoder
4023.
[0426] [1] Among data block groups in the interleaved arrangement, extents that
belong to a different file, for example a BD-J object file, may be recorded. FIG. 65A
is a schematic diagram showing data blocks in an interleaved arrangement that
includes only multiplexed stream data. FIG. 65B is a schematic diagram showing
data blocks in an interleaved arrangement that includes extents belonging to another
file.
[0427] As shown in FIG. 65A, the data block group 6501 includes depth map data
blocks D1, D2, and D3, right-view data blocks R1, R2, and R3, and base-view data
blocks L1, L2, and L3 in an alternating arrangement. In the playback path 6502 in
L/R mode, pairs of adjacent right-view and left-view data blocks R1+L1, R2+L2,
and R3+L3 are read in order. In each pair, a zero sector transition J0 occurs between
the right-view data block and the base-view data block. Furthermore, reading of
each depth map data block D1, D2, and D3 is skipped by a jump Jlr. In the playback
path 6503 in depth mode, depth map data blocks D1, D2, and D3 and base-view data
blocks L1, L2, and L3 are alternately read. A zero sector transition jump J0 occurs
between adjacent base-view data blocks and depth map data blocks. Furthermore,
reading of each right-view data block R1, R2, and R3 is skipped by a jump JLD.
[0428] On the other hand, as shown in FIG. 65B, extents A1 and A2 belonging to a
different file are inserted among the data block group 6504, which is the same as in
FIG. 65A. This "different file" may be, for example, a movie object file, BD-J
object file, or JAR file. These extents Al and A2 are both inserted between a depth
map data block and right-view data block that are adjacent in FIG. 65A. In this case,
in the playback path 6505 in L/R mode, the distance of the jump JLR is longer than in
the playback path 6502 shown in FIG. 65A. However, the zero sector transition
jump J0 need not be changed into a regular jump, which is not the case if the extents
A1 and A2 are inserted next to a base-view data block. The same is true for the
playback path 6506 in depth mode. As is clear from FIG. 57, the maximum jump
time generally increases more when changing a zero sector transition to a regular
jump than when changing the jump distance. Accordingly, as is clear from
expressions 2-5, the minimum extent size generally increases more when changing a
zero sector transition to a regular jump than when changing the jump distance.
Therefore, when inserting extents Al and A2 into the data block group 6501, which
is in the interleaved arrangement, the extents Al and A2 are inserted between depth
map data blocks and right-view data blocks, as shown in FIG. 65B. The increase in
minimum extent size caused by this insertion is thereby suppressed, making it
possible to avoid increasing the minimum capacity of the read buffers.
[0429] Furthermore, in the arrangement shown in FIG. 65B, the sizes in sectors G1
and G2 of the extents A1 and A2 may be restricted to be equal to or less than the
maximum jump distance MAX_EXTJUMP3D: G1 < MAXEXTJUMP3D and G2 <
MAX_EXTJUMP3D. This maximum jump distance MAX_EXTJUMP3D
represents, in sectors, the maximum jump distance among the jumps Jlr and Jld
occurring within the data block group 6504. With this restriction, the maximum
jump time that is to be substituted in the right-hand side of expressions 2-5 does not
easily increase, and thus the minimum extent size does not easily increase.
Accordingly, it is possible to avoid an increase in the minimum capacity of the read
buffers due to insertion of the extents Al and A2.
[0430] Additionally, the sums of (i) the sizes G1 and G2 of the extents Al and A2
and (ii) the sizes Sext3[2], Sext2[2], Sext3[3], and Sext2[3] of the dependent-view data
blocks D2, R2, D3, and R3 contiguous with the extents Al and A2 may be restricted
to be equal to or less than the maximum jump distance MAX_EXTJUMP3D.
[0431]
CEIL(Sext3[2] / 2048) + G1 < MAX_EXTJUMP3D,
CEIL(Sext2[2] / 2048) + G1 < MAX_EXTJUMP3D,
CEIL(Sext3[3] / 2048) + G2 < MAX_EXTJUMP3D,
CEIL(Sext2[3] / 2048) + G2 < MAX_EXTJUMP3D.
[0432] In these expressions, the size in bytes of a dependent-view data block is
divided by 2048, the number of bytes per sector, to change the units of the size from
bytes to sectors. As long as these conditions are met, the maximum jump time to be
inserted into the right-hand side of expressions 2-5 does not exceed a fixed value.
For example, if the maximum jump distance MAX_EXTJUMP3D is fixed at 40000
sectors, then the maximum jump time from FIG. 57 does not exceed 350 ms.
Accordingly, the minimum extent size does not exceed a fixed value. It is thus
possible to reliably avoid an increase in the minimum capacity of the read buffers
due to insertion of the extents Al and A2.
[0433] Apart from the above restrictions, the sums of (i) the sizes G1 and G2 of the
extents Al and A2 and (ii) the sizes Sext3[2], Sext2[2], Sext3[3], and Sext2[3] of the
dependent-view data blocks D2, R2, D3, and R3 adjacent to the extents Al and A2
may be further restricted to be equal to or less than the maximum jump distance
MAX_JUMP(.) corresponding to the size of each dependent-view data block.
[0434]
CEIL(Sext3[2] / 2048) + G1 < MAX_JUMP(Sext3[2]),
CEIL(Sext2[2] / 2048) + G1 < MAX_JUMP(Sext2[2]),
CEIL(Sext3[3] / 2048) + G2 < MAX_JUMP(Sext3[3]),
CEIL(Sext2[3] / 2048) + G2 < MAX_JUMP(Sext2[3]).
[0435] When the size of the dependent-view data block is expressed in sectors and
the corresponding maximum jump time obtained from the table in FIG. 57, the
maximum jump distance MAX_JUMP(•) refers to the maximum value of the range
of sectors to which the maximum jump time corresponds. For example, if the size of
the dependent-view data block is 5000 sectors, then the maximum jump time in the
table in FIG. 57 for 5000 sectors is 250 ms, which corresponds to a range of "1 -
10000 sectors". Accordingly, the maximum jump distance MAX_JUMP (5000 x
2048 bytes) is the maximum value in this range, i.e. 10000 sectors. As long as the
above conditions are met, the maximum jump time to be inserted into the right-hand
side of expressions 2-5 does not change, and thus the minimum extent size does not
change. Accordingly, it is possible to reliably avoid an increase in the minimum
capacity of the read buffers due to insertion of the extents A1 and A2.
[0436] [M] Read Buffer Margin Amounts
[0437] The lower limits UL1 and UL2 of the stored data amounts DA1 and DA2 in
the read buffers 4021 and 4022, shown in FIGS. 59A, 59B, 60A, and 60B, represent
buffer margin amounts. The "buffer margin amount" is the lower limit of the stored
data amount that is to be maintained in each read buffer during reading of data block
groups in the interleaved arrangement. The buffer margin amount is set to the
amount at which underflow in the read buffers can be prevented during a long jump.
[0438] A "long jump" is a collective term for jumps with a long seek time and
specifically refers to a jump distance that exceeds a predetermined threshold value.
This threshold value depends on the type of optical disc and on the disc drive's read
processing capability and is specified, for example, as 40000 sectors in the
BD-ROM standard. Long jumps particularly include focus jumps and track jumps.
When the BD-ROM disc 101 has multiple recording layers, a "focus jump" is a
jump caused by switching the recording layer from which the drive reads. A focus
jump particularly includes processing to change the focus distance of the optical
pickup. A "track jump" includes processing to move the optical pickup in a radial
direction along the BD-ROM disc 101.
[0439] During reading of stream data, a long jump occurs when the recording layer
being read is switched or when read processing is interrupted to read from another
file. The term "another file" refers to a file other than the AV stream file shown in
FIG. 2 and includes, for example, a movie object file 212, BD-J object file 251, and
JAR file 261. The long jump is longer than jumps derived from expressions 2-5.
Furthermore, the timing of a long jump caused by interruption to read another file is
irregular and may occur even during the reading of a single data block. Accordingly,
rather than setting the minimum extent size by substituting the maximum jump time
of a long jump into expressions 2-5, it is more advantageous to maintain the buffer
margin amount.
[0440] FIG. 66 is a schematic diagram showing the long jumps JLY, JbdjI, and JBdj2
produced during playback processing in L/R mode. As shown in FIG. 66, a layer
boundary LB represents a boundary between two recording layers. A first 3D extent
block 6601 is recorded on the first recording layer, which is located before the layer
boundary LB, and a second 3D extent block 6602 is recorded on the second
recording layer, which is located after the layer boundary LB. A "3D extent block"
refers to successive data block groups recorded in the interleaved arrangement. As
shown in FIG. 65B, the 3D extent block may include extents from another file.
Furthermore, a BD-J object file 6603 is recorded in an area distant from both 3D
extent blocks 6601 and 6602. When playback processing proceeds from the first 3D
extent block 6601 to the second 3D extent block 6602, a long jump JLY occurs due to
switching layers. In contrast, reading of the first 3D extent block 6601 is interrupted
for reading of the BD-J object file 6603, and thus a pair of long jumps JBdj1 and
JBdj2 occur. The buffer margin amounts UL1 and UL2 necessary for the long jumps
JLY and JBdj are calculated as follows.
[0441] The maximum jump time Tjump-LY for a long jump JLY caused by layer
switching equals the sum of the layer switching time and the maximum jump time,
as per the table in FIG. 57, corresponding to the jump distance of the first long jump
JLY. This jump distance equals the number of sectors between the end of the
base-view data block L3, the last block in the first 3D extent block 6601, and the
beginning of the top right-view data block R4 in the second 3D extent block 6602.
The layer switching time refers to the time necessary to switch recording layers,
such as for a focus jump, and for example equals 350 ms. Note also that the
base-view transfer rate Rext1 does not exceed the maximum value Rmax1. It thus
follows that the data amount read from the first read buffer 4021 during the long
jump JLY does not exceed the product of the maximum value Rmax1 of the base-view
transfer rate and the maximum jump time Tjump-LY. The value of this product is set as
the first buffer margin amount UL1. In other words, the first buffer margin amount
UL1 is calculated via expression 8.
[0442]

[0443] For example, when the maximum jump distance is 40000 sectors, then as per
the table in FIG. 57, the maximum jump time Tjump-LT is 700 ms, which includes the
layer switching time of 350 ms. Accordingly, when the system rate corresponding to
the file 2D is 48 Mbps, the first buffer margin amount UL1 equals (48 Mbps x 192 /
188) x 0.7 seconds = approximately 4.09 MB.
[0444] Similarly, the maximum value of the data amount read from the second read
buffer 4022 during the long jump JLY, i.e. the product of the maximum value Rmax2
of the right-view transfer rate and the maximum jump time Tjump-LY, is determined to
be the second buffer margin amount UL2. In other words, the second buffer margin
amount UL2 is calculated via expression 9.
[0445]

[0446] For example, when the maximum jump distance is 40000 sectors, meaning
that the maximum jump time Tjump-LY is 700 ms, and when the system rate
corresponding to the first file DEP is 16 Mbps, the second buffer margin amount
UL2 equals (16 Mbps x 192 /188) x 0.7 seconds = approximately 1.36 MB.
[0447] Referring again to FIG. 66, when reading of the BD-J object file 6603
interrupts the read period of the first 3D extent block 6601, the first long jump JBdj1
occurs. In this way, the position targeted for reading shifts from the recording area
of the second base-view data block L2 to the recording area of the BD-J object file
6603. The corresponding jump time TBDJ is set to a predetermined fixed value, e.g.
900 ms. Next, the BD-J object file 6603 is read. The time required for reading equals
the value of eight times the size SBdj of the extent belonging to the file 6603 divided
by the read rate Rud-3D, or 8 x SBDJ[n] / Rud-3D (normally, the extent size SBdj is
expressed in bytes, and the read rate Rud-3D in bits/second; therefore, it is necessary
to multiply by eight). Next, the second long jump JBDJ2 occurs. The position targeted
for reading thus returns from the recording area of the BD-J object file 6603 back to
the recording area of the second base-view data block L2. The corresponding jump
time TBDJ is equal to the first jump period, e.g. 900 ms. During the two jumps JBDJ1
and JBDJ2 and the reading of the BD-J object file 6603, data is not read into the first
read buffer 4021. Accordingly, the maximum value of the amount of data read from
the first read buffer 4021 during this time is determined to be the first read buffer
margin amount UL1. In other words, the first read buffer margin amount UL1 is
calculated via expression 10.
[0448]

[0449] Similarly, the maximum value of the data amount read from the second read
buffer 4022 during the two long jumps JBDJ1 and JBDJ2 and reading of the BD-J
object file 6603 is determined to be the second buffer margin amount UL2. In other
words, the second buffer margin amount UL2 is calculated via expression 11.
[0450]

[0451] The first buffer margin amount UL1 is set to the larger of the values of the
right-hand side of expressions 8 and 10. The second buffer margin amount UL2 is
set to the larger of the values of the right-hand side of expressions 9 and 11.
[0452] [N] Minimum Capacity of the Read Buffers
[0453] During playback processing of the successive data block groups shown in
FIGS. 59C and 60C, the minimum value of the capacity necessary for each of the
read buffers 4021 and 4022 is calculated as follows.
[0454] When the nth base-view data block Ln (n = 0, 1,2, ...) is read in 3D playback
mode, the capacity necessary for the first read buffer 4021, RBl[n], should be equal
to or greater than the peak, among the peaks in the graphs shown in FIGS. 59A and
60A, at the time of completion of reading of the nth base-view data block Ln.
Accordingly, the capacity RBl[n] should satisfy expression 12 in both L/R mode
and depth mode.
[0455]

[0456] When the nth right -view data block Rn is read in L/R mode, the capacity
necessary for the second read buffer 4022, RB2LR[n], should be equal to or greater
than the peak, among the peaks in the graph shown in FIG. 59B, at the time of
completion of reading of the nth right-view data block Rn. Accordingly, the capacity
RB2LR[n] should satisfy expression 13.
[0457]

[0458] Any of the right-view data blocks may be read first by interrupt playback. In
such a case, the system target decoder 4023 does not read data from the second read
buffer 4022 until the entire right-view data block that is read first is stored in the
second read buffer 4022. Accordingly, unlike the capacity RBl[n] of the first read
buffer 4021, the capacity RB2LR[n] of the second read buffer 4022 needs to further
meet the condition of being "at least larger than the size Sext2[n] of the nth right-view
data block Rn", as shown in expression 13.
[0459] Similarly, when reading the nth depth map data block Dn, the capacity
RB2LD[n] of the second read buffer 4022 should satisfy expression 14.
[0460]

[0461] [O] Arrangement of Multiplexed Stream Data Before and After a Layer
Boundary
[0462] When the BD-ROM disc 101 includes multiple recording layers, the main TS
and sub-TS may be recorded across a layer boundary on two recording layers. In this
case, a long jump occurs during reading of the main TS and sub-TS.
[0463] FIG. 67A is a schematic diagram showing data block groups 6701 and 6702
recorded before and after a layer boundary LB. As shown in FIG. 67A, on the
recording layer located before the layer boundary LB, the depth map data block
group ..., D1, D2, the right-view data block group ..., R1, R2, and the base-view
data block group ..., L1, L2 are recorded in an interleaved arrangement, thus
constituting the first 3D extent block 6701. On the other hand, on the recording layer
located after the layer boundary LB, the depth map data block group D3, ..., the
right-view data block group R3, ..., and the base-view data block group L3, ... are
recorded in an interleaved arrangement, thus constituting the second 3D extent block
6702. The interleaved arrangements of 3D extent blocks 6701 and 6702 are the same
as the arrangement 1501 shown in FIG. 15. Furthermore, stream data is continuous
between the three data blocks D2, R2, and L2 located at the end of the first 3D
extent block 6701 and the three data blocks D3, R3, and L3 located at the top of the
second 3D extent block 6702.
[0464] As in the arrangement 1501 shown in FIG. 15, the data blocks shown in FIG.
67A can be accessed as extents in a file 2D, file DEP, or file SS. In particular, the
file 2D and file SS share the base-view data blocks. For example, base-view data
blocks L1-L3 can each be accessed respectively as 2D extents
EXT2D[0]-EXT2D[2] in file 2D 241. On the other hand, each pair of contiguous
right-view data blocks and base-view data blocks Rl+Ll, R2+L2, and R3+L3 can
respectively be accessed as 3D extents EXTSS[0], EXTSS[1], and EXTSS[2] in the
first file SS 244A.
[0465] FIG 67B is a schematic diagram showing playback paths 6710, 6711, and
6712 in each playback mode for 3D extent blocks 6701 and 6702. As shown in FIG.
67B, both playback path 6710 in 2D playback mode and playback path 6711 in L/R
mode traverse the same base-view data block L2 immediately before a long jump
Jly-
[0466] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 6710 in 2D playback mode, the
base-view data block L1 located second from the end in the first 3D extent block
6701 is first read as 2D extent EXT2D[0]. Reading of the immediately subsequent
depth map data block D2 and right-view data block R2 is skipped by the first jump
J2d1- Next, the last base-view data block L2 in the first 3D extent block 6701 is read
as the second 2D extent EXT2D[1]. Immediately thereafter, a long jump JLY occurs,
and reading of the two data blocks D3 and R3 located at the top of the second 3D
extent block 6702 is skipped. Subsequently, the top base-view data block L3 in the
second 3D extent block 6702 is read as the third 2D extent EXT2D[2].
[0467] The playback device playback device 102 in L/R mode plays back the first
file SS 244A. Accordingly, as shown by the playback path 6711 in L/R mode, the
pair R1+L1 of the top right-view data block Rl and the immediately subsequent
base-view data block L1 is consecutively read as the first 3D extent EXTSS[0].
Reading of the immediately subsequent depth map data block D2 is skipped by the
first jump Jlr1. Next, the second right-view data block R2 and the last base-view
data block L2 are consecutively read as the second 3D extent EXTSS[1]. A long
jump JLY occurs immediately thereafter, and reading of the top depth map data block
D3 in the second 3D extent block 6702 is skipped. Subsequently, the top right-view
data block R3 and the immediately subsequent base-view data block L3 in the
second 3D extent block 6702 are consecutively read as the third 3D extent
EXTSS[2].
[0468] During the long jump JLY, the BD-ROM drive stops reading, but the system
target decoder continues to decode stream data. Accordingly, for the playback
device 102 to play back video images seamlessly before and after the long jump JLY,
buffer underflow has to be prevented during a long jump JLY.
[0469] The playback device 102 in L/R mode stores buffer margin amounts UL1
and UL2 in the read buffers 4021 and 4022 while decoding the first 3D extent block
6701. During a long jump JLY, data corresponding to the buffer margin amounts UL1
and UL2 is decoded in addition to the data in the 3D extent EXTSS[1] = R2 + L2
read immediately before the long jump JLY. Accordingly, the buffer margin amounts
UL1 and UL2 should be large enough to prevent buffer underflow in L/R mode.
[0470] For example, it is presumed that the buffer margin amounts UL1 and UL2
are sought via expressions 8 and 9, assuming that the jump distance Sjum_max for the
long jump JLY is 40000 sectors. In this case, the buffer margin amounts UL1 and
UL2 alone can prevent underflow in the read buffers 4021 and 4022 during the
maximum jump time Tjump_max = 700 ms. This maximum jump time Tjump_max for the
long jump JLY produced when changing layers includes a layer switching time of
350 ms in addition to the maximum jump time Tjump_max = 350 ms corresponding to
the jump distance Sjump as per the table in FIG. 57. Accordingly, as long as the actual
jump time for the long jump JLY is equal to or less than 700 ms, the size of the data
blocks R2 and L2 should be values Smin2 and Sminl for which the buffer margin
amounts can be maintained until immediately before a long jump JLY. In other words,
these values Smin2 and Sminl should be calculated by substituting the maximum
jump time Tjump_max for the long jump JLY minus the layer switching time into the
right-hand side of expressions 3 and 2 as the jump time Tjump_3D[n]. As a result, the
size Smin2 and Sminl of the data blocks R2 and L2 equal the minimum extent size
if "two 3D extent blocks 6701 and 6702 are contiguously recorded".
[0471] On the other hand, to prevent buffer underflow in 2D playback mode, the
following two conditions should be met: first, the size Sext2D[1] of the 2D extent
EXT2D[1], i.e. the base-view data block L2, should satisfy expression 1. Next, the
number of sectors from the last 2D extent in the first 3D extent block 6701 to the top
2D extent in the second 3D extent block 6702 should be equal to or less than the
maximum jump distance Sjump_max for the long jump JLY specified in accordance with
the capabilities of the 2D playback device. The size Sext2D[1] satisfying expression 1
is generally larger than the minimum extent size Sminl in L/R mode, as shown in
FIG. 67B. Accordingly, the capacity of the first read buffer 4021 must be larger than
the minimum value necessary for seamless playback in L/R mode. Furthermore, the
extent ATC times are the same for the right-view data block R2 and base-view data
block L2 included in the same 3D extent EXTSS[1]. Accordingly, the size Sext2[1] of
the right-view data block R2 is generally larger than the minimum extent size Smin2
in L/R mode. Therefore, the capacity of the second read buffer 4022 has to be larger
than the minimum value necessary for seamless playback in L/R mode.
[0472] As per the above description, seamless playback of video images is possible
even during a long jump between two 3D extent blocks 6701 and 6702 in the
arrangement shown in FIG. 67A. However, a sufficiently large capacity has to be
guaranteed in the read buffers 4021 and 4022 in the playback device 102 in L/R
mode.
[0473] To reduce the capacity of the read buffers 4021 and 4022 while still
permitting seamless playback of video images during a long jump, changes may be
made in the interleaved arrangement of data blocks before and after a position where
a long jump is necessary, such as a layer boundary. These changes are represented,
for example, by the following six types of arrangements 1-6. With any of the
arrangements 1-6, as described below, the playback device 102 can easily perform
seamless playback of video images during a long jump while keeping the necessary
capacity of the read buffers 4021 and 4022 to a minimum.
[0474] [0-1] Arrangement 1
[0475] FIG. 68A is a schematic diagram showing a first example of a physical
arrangement of a data block group recorded before and after a layer boundary LB on
a BD-ROM disc 101. Hereinafter, this arrangement is referred to as "arrangement 1".
As shown in FIG. 68A, the first 3D extent block 6801 is recorded before the layer
boundary LB, and the second 3D extent block 6802 is recorded after the layer
boundary LB. The 3D extent blocks 6801 and 6802 are the same as the blocks 6701
and 6702 shown in FIG. 67A. In arrangement 1, one base-view data block L32d is
further placed between the end L2 of the first 3D extent block 6801 and the layer
boundary LB. This base-view data block L32d matches bit-for-bit with a base-view
data block L3Ss at the top of the second 3D extent block 6802. Hereinafter, L32d is
referred to as a "block exclusively for 2D playback", and L3Ss is referred to as a
"block exclusively for 3D playback".
[0476] The data blocks shown in FIG. 68A can be accessed as extents in either file
2D or file DEP, with the exception of the block exclusively for 3D playback L3SS.
For example, the base-view data block L1 second from the end of the first 3D extent
block 6801, the pair L2+L32D of the last base-view data block L2 and the block
exclusively for 2D playback L32D, and the second base-view data block L4 in the
second 3D extent block 6802 can respectively be accessed as individual 2D extents
EXT2D[0], EXT2D[1], and EXT2D[2] in the file 2D 241.
[0477] For the data block groups shown in FIG. 68A, cross-linking of AV stream
files is performed as follows. Each pair of contiguous right-view and base-view data
blocks R1+L1, R2+L2, R3+L3SS, and R4+L4 in the 3D extent blocks 6801 and 6802
can be accessed respectively as individual 3D extents EXTSS[0], EXTSS[1],
EXTSS[2], and EXTSS[3] in the first file SS 244A. In this case, with the exception
of the 3D extent EXTSS[2] immediately after the layer boundary LB, the 3D extents
EXTSS[0], EXTSS[1], and EXTSS[3] respectively share base-view data blocks L1,
L2, and L4 with the file 2D 241. On the other hand, the block exclusively for 2D
playback L32d can be accessed as part of the extent EXT2D[1] in the file 2D 241,
the extent EXT2D[1] being located immediately before the layer boundary LB.
Furthermore, the block exclusively for 3D playback L3SS can be accessed as part of
the 3D extent EXTSS[2], located immediately after the layer boundary LB.
[0478] FIG. 68B is a schematic diagram showing a playback path 6810 in 2D
playback mode, playback path 6820 in L/R mode, and a playback path 6830 in depth
mode for the data block group shown in FIG. 68A.
[0479] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 6810 in 2D playback mode, first the
base-view data block L1, which is second from the end of the first 3D extent block
6801, is read as the first 2D extent EXT2D[0], and reading of the immediately
subsequent depth map data block D2 and right-view data block R2 is skipped by a
first jump J2D1. Next, a pair L2+L32D of the last base-view data block L2 in the first
3D extent block 6810 and the immediately subsequent block exclusively for 2D
playback L32D is continuously read as the second 2D extent EXT2D[1]. A long jump
JLY occurs at the immediately subsequent layer boundary LB, and reading of the five
data blocks D3, R3, L3Ss, D4, and R4, located at the top of the second 3D extent
block 6802, is skipped. Next, the second base-view data block L4 in the second 3D
extent block 6802 is read as the third 2D extent EXT2D[2].
[0480] The playback device 102 in L/R mode plays back the first file SS 244A.
Accordingly, as shown by the playback path 6820 in L/R mode, first a pair R1+L1
of the top right-view data block R1 and the immediately subsequent base-view data
block L1 is read continuously as the first 3D extent EXTSS[0], and reading of the
immediately subsequent depth map data block D2 is skipped by a first jump Jlr1.
Next, the second right-view data block R2 and the immediately subsequent
base-view data block L2 are read continuously as the second 3D extent EXTSS[1].
A long jump JLy occurs immediately thereafter, and reading of the block exclusively
for 2D playback L32d and the top depth map data block D3 in the second 3D extent
block 6802 is skipped. Next, the top right-view data block R3 in the second 3D
extent block 6802 and the immediately subsequent block exclusively for 3D
playback L3Ss are read continuously as the third 3D extent EXTSS[2], and reading
of the immediately subsequent depth map data block D4 is skipped by a second
jump JLR2. Furthermore, the next right-view data block R4 and the immediately
subsequent base-view data block L4 are read continuously as the fourth 3D extent
EXTSS[3].
[0481] As shown in FIG. 68B, in 2D playback mode, the block exclusively for 2D
playback L32d is read, whereas reading of the block exclusively for 3D playback
L3SS is skipped. Conversely, in L/R mode, reading of the block exclusively for 2D
playback L32d is skipped, whereas the block exclusively for 3D playback L3Ss is
read. However, since the data blocks L32d and L3SS match bit-for-bit, the left-view
video frames that are played back are the same in both playback modes. In
arrangement 1, the playback path 6810 in 2D playback mode and the playback path
6820 in L/R mode are divided before and after the long jump JLy in this way. The
same is also true for depth mode. Accordingly, unlike the arrangement shown in FIG.
67A, the size Sext2D[1] of the 2D extent EXT2D[1] located immediately before the
layer boundary LB and the size Sext2[1] of the immediately preceding right-view data
block R2 can be determined separately as follows.
[0482] The size Sext2D[1] of the 2D extent EXT2D[1] equals Sextl[1] + S2D, the sum
of the size Sexti[1] of the base-view data block L2 and the size S2D of the block
exclusively for 2D playback L32D. Accordingly, for seamless playback in 2D
playback mode, this sum Sext1[1] + S2d first should satisfy expression 1. Next, the
number of sectors from the end of the block exclusively for 2D playback L32d to the
first 2D extent EXT2D[2] = L4 in the second 3D extent block 6802 should be equal
to or less than the maximum jump distance Sjump_max for the long jump JLY specified
in accordance with the capabilities of the 2D playback device.
[0483] On the other hand, for seamless playback in L/R mode, the sizes Sext2[1] and
Sext1[1] of the right-view data block R2 and base-view data block L2 located
immediately before the layer boundary LB should satisfy expressions 3 and 2. The
maximum jump time Tjump_max for the long jump JLy minus the layer switching time
should be substituted into the right-hand side of these expressions as the jump time
Tjump-3D- Next, the number of sectors from the end of the 3D extent EXTSS[1] to the
top of the first 3D extent EXTSS[2] in the second 3D extent block 6802 should be
equal to or less than the maximum jump distance Sjump_max for the long jump JLY
specified in accordance with the capabilities of the 3D playback device.
[0484] Only the base-view data block L2 located at the front of the 2D extent
EXT2D[1] is shared with the 3D extent EXTSS[1]. Accordingly, by appropriately
enlarging the size S2D of the block exclusively for 2D playback L32D, the size Sextl[1]
of the base-view data block L2 can be further limited while keeping the size Sext2D[1]
= Sext1[1] + S2D of the 2D extent EXT2D[1] constant. As a result, the size Sext2[1] of
the right-view data block R2 can also be further limited.
[0485] Since the block exclusively for 3D playback L3SS and the block exclusively
for 2D playback L32D match bit for bit, enlarging the size S2d of the block
exclusively for 2D playback L32D enlarges the size of the right-view data block R3
located immediately before the block exclusively for 3D playback L3SS. However,
this size can be made sufficiently smaller than the size of the right-view data block
R2 located immediately before the layer boundary LB shown in FIG. 6 7A. The
capacity of the read buffers 4021 and 4022 to be guaranteed in the playback device
102 in L/R mode can thus be brought even closer to the minimum amount necessary
for seamless playback in L/R mode.
[0486] It is thus possible to set each data block in arrangement 1 to be a size at
which seamless playback of video images during a long jump is possible in both 2D
playback mode and L/R mode while keeping the read buffer capacity that is to be
guaranteed in the playback device 102 to the minimum necessary. The same is also
true for depth mode.
[0487] [0-2] Arrangement 1 Supporting L/R Mode Only
[0488] When playing back 3D video images in L/R mode only, the depth map
blocks may be removed from arrangement 1. FIG. 69 is a schematic diagram
showing arrangement 1 in FIG. 68A with the depth map data blocks removed. As
shown in FIG. 69, a dependent-view data block group ..., D[0], D[1] and a
base-view data block group ..., B[0], B[1] are recorded in an interleaved
arrangement in the first 3D extent block 6901 located before the layer boundary LB.
On the other hand, a dependent-view data block group D[2], D[3], ... and a
base-view data block group B[2]ss, B[3], ... are recorded in an interleaved
arrangement in the second 3D extent block 6902 located after the layer boundary LB.
Furthermore, a block exclusively for 2D playback B[2]2d is placed between the end
B[1] of the first 3D extent block 6901 and the layer boundary LB, and a block
exclusively for 3D playback B[2]ss is placed at the top of the second 3D extent
block 6902. These data blocks B[2]2D and B[2]ss match bit-for-bit.
[0489] In the interleaved arrangement of the 3D extent blocks 6901 and 6902,
dependent-view data blocks D[n] and base-view data blocks B[n] alternate.
Furthermore, the extent ATC time is equal for each set of two contiguous data
blocks D[0], B[0]; D[1], B[1]; D[2], B[2]ss; and D[3], B[3]. The content of each
piece of stream data is continuous between the two data blocks D[1] and B[1]
located at the end of the first 3D extent block 6901 and the two data blocks D[2] and
B[2]Ss located at the top of the second 3D extent block 6902.
[0490] With the exception of the block exclusively for 3D playback B[2]ss, the data
blocks shown in FIG. 69 can each be accessed as an extent in one of file 2D 6910
and file DEP 6912. For example, the base-view data block B[0] located second from
the end in the first 3D extent block 6901, the pair B[1]+B[2]2d of the last base-view
data block in the first 3D extent block 6901 and the block exclusively for 2D
playback, and the second base-view data block B[3] in the second 3D extent block
6902 can respectively be accessed as individual 2D extents EXT2D[0], EXT2D[1],
and EXT2D[2] in the file 2D 6910.
[0491] For the data block groups shown in FIG. 69, cross-linking of AV stream files
is performed as follows. Each set of contiguous dependent-view and base-view data
blocks D[0]+B[0]+D[1]+B[1] and D[2]+B[2]ss+D[3]+B[3] in the 3D extent blocks
6901 and 6902 can be accessed respectively as individual 3D extents EXTSS[0] and
EXTSS[1] in the file SS 6920. In this case, the 3D extents EXTSS[0] and EXTSS[1]
share base-view data blocks B[0], B[1], and B[3] with the file 2D 6910. On the other
hand, the block exclusively for 2D playback B[2]2d can be accessed as part of the
2D extent EXT2D[1] located immediately before the layer boundary LB.
Furthermore, the block exclusively for 3D playback B[2]ss can be accessed as part
of the 3D extent EXTSS[1], located immediately after the layer boundary LB.
[0492] The playback device 102 in 2D playback mode plays back the file 2D 6910.
Accordingly, like the playback path 6810 in 2D playback mode shown in FIG. 68B,
only the 2D extent EXT2D[0] = B[0], EXT2D[1] = B[1] + B[2]2D, and EXT2D[2] =
B[3] are read, whereas reading of other data blocks is skipped by jumps.
[0493] The playback device 102 in L/R mode plays back the file SS 6920.
Accordingly, data blocks other than the block exclusively for 2D playback B[2]2D
are consecutively read as 3D extents EXTSS[0] and EXTSS[1], and only the reading
of the block exclusively for 2D playback B[2]2D is skipped.
[0494] As per the above description, in 2D playback mode, the block exclusively for
2D playback B[2]2d is read, whereas reading of the block exclusively for 3D
playback B[2]ss is skipped. Conversely, in L/R mode, reading of the block
exclusively for 2D playback B[2]2D is skipped, whereas the block exclusively for 3D
playback B[2]Ss is read. Since the data blocks B[2]2D and B[2]ss match bit-for-bit,
however, the left-view video frames that are played back are the same in either
playback mode. In arrangement 1 therefore, even in the case of supporting only L/R
mode, the playback path in 2D playback mode and the playback path in L/R mode
are separate before and after a long jump JLY. Accordingly, by appropriately
enlarging the size S2D of the block exclusively for 2D playback B[2]2D, the following
four conditions can simultaneously be met. (i) The size of the 2D extent EXT2D[1]
= B[1] + B[2]2D satisfies expression 1. (ii) The number of sectors from the end of the
block exclusively for 2D playback B[2]2D to the first 2D extent EXT2D[2] = B[3] in
the second 3D extent block 6902 is equal to or less than the maximum jump distance
SjumP_max for the long jump JLY specified in accordance with the capabilities of the 2D
playback device, (iii) The sizes of the dependent-view data block D[1] and the
base-view data block B[1] located immediately before the layer boundary LB satisfy
expressions 3 and 2. The maximum jump time Tjump_max for the long jump JLY minus
the layer switching time should be substituted into the right-hand side of these
expressions as the jump time Tjump-3D. (iv) The number of sectors from the end of the
3D extent EXTSS[0] to the top of the first 3D extent EXTSS[1] in the second 3D
extent block 6902 is equal to or less than the maximum jump distance Sjump_max for
the long jump JLY specified in accordance with the capabilities of the 3D playback
device. As a result of these conditions, the capacity of the read buffers 4021 and
4022 to be guaranteed in the playback device 102 in L/R mode can thus be brought
even closer to the minimum amount necessary for seamless playback in L/R mode.
[0495] Even when arrangement 1 supports only L/R mode, it is thus possible to set
each data block to be a size at which seamless playback of video images during a
long jump is possible in both 2D playback mode and L/R mode while keeping the
read buffer capacity that is to be guaranteed in the playback device 102 to the
minimum necessary.
[0496] [0-3] Arrangement 2
[0497] FIG. 70A is a schematic diagram showing a second example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101. Hereinafter, this arrangement is referred to as "arrangement
2". As shown by comparing FIG. 70A with FIG. 68A, arrangement 2 differs from
arrangement 1 by including two blocks exclusively for 3D playback L3SS and L4SS at
the top of the second 3D extent block 7002. The blocks exclusively for 3D playback
L3Ss and L4SS match bit-for-bit with the block exclusively for 2D playback
(L3+L4)2D located immediately before the layer boundary LB. The other
characteristics of arrangement 2 are the same as arrangement 1, and thus a detailed
description thereof can be found in the description for arrangement 1.
[0498] The data blocks shown in FIG. 70A can be accessed as extents in either file
2D or file DEP, with the exception of the blocks exclusively for 3D playback L3SS
and L4SS. For example, the base-view data block L1 second from the end of the first
3D extent block 7001, the pair L2+(L3+L4)2D of the last base-view data block L2
and the block exclusively for 2D playback (L3+L4)2D, and the third base-view data
block L5 in the second 3D extent block 7002 can respectively be accessed as
individual 2D extents EXT2D[0], EXT2D[1], and EXT2D[2] in the file 2D 241.
[0499] For the data block groups shown in FIG. 70A, cross-linking of AV stream
files is performed as follows. Each pair of contiguous right-view and base-view data
blocks Rl+Ll, R2+L2, R3+L3SS, R4+L4SS, and R5+L5 in the 3D extent blocks 7001
immediately subsequent depth map data block D2 is skipped by a first jump JlrI.
Next, the second right-view data block R2 and the immediately subsequent
base-view data block L2 are read continuously as the second 3D extent EXTSS[1].
A long jump JLY occurs immediately thereafter, and reading of the block exclusively
for 2D playback (L3+L4)2d and the top depth map data block D3 in the second 3D
extent block 7002 is skipped. Next, the top right-view data block R3 in the second
3D extent block 7002 and the immediately subsequent block exclusively for 3D
playback L3SS are read continuously as the third 3D extent EXTSS[2], and reading
of the immediately subsequent depth map data block D4 is skipped by a second
jump JLR2. Similarly, the next right-view data block R4 and the immediately
subsequent block exclusively for 3D playback L4SS are read continuously as the
fourth 3D extent EXTSS[3], and reading of the immediately subsequent depth map
data block D5 is skipped by a third jump Jlr3. Furthermore, the next right-view data
block R5 and the immediately subsequent base-view data block L5 are read
continuously as the fifth 3D extent EXTSS[4].
[0503] As shown in FIG. 70B, in 2D playback mode, the block exclusively for 2D
playback (L3+L4)2D is read, whereas reading of the blocks exclusively for 3D
playback L3Ss and L4SS is skipped. Conversely, in L/R mode, reading of the block
exclusively for 2D playback (L3+L4)2d is skipped, whereas the blocks exclusively
for 3D playback L3SS and L4SS are read. However, since the block exclusively for
2D playback (L3+L4)2D matches the blocks exclusively for 3D playback L3SS and
L4SS bit-for-bit, the left-view video frames that are played back are the same in both
playback modes. In arrangement 2, the playback path 7010 in 2D playback mode
and the playback path 7020 in L/R mode are divided before and after the long jump
JLY in this way. Accordingly, the size Sextd[1] of the 2D extent EXT2D[1] located
immediately before the layer boundary LB and the size Sext2[1] of the immediately
preceding right-view data block R2 can be determined separately as follows. The
same is also true for depth mode.
and 7002 can be accessed respectively as individual 3D extents EXTSS[0],
EXTSS[1], EXTSS[2], EXTSS[3], and EXTSS[4] in the first file SS 244A. In this
case, with the exception of the two 3D extents EXTSS[2] and EXTSS[3]
immediately after the layer boundary LB, the 3D extents EXTSS[0], EXTSS[1], and
EXTSS[4] respectively share base-view data blocks L1, L2, and L5 with 2D extents
EXT2D[0], EXT2D[1], and EXT2D[2]. On the other hand, the block exclusively for
2D playback (L3+L4)2D can be accessed as part of the 2D extent EXT2D[1].
Furthermore, the blocks exclusively for 3D playback L3Ss and L4SS can be accessed
as part of the 3D extents EXTSS[2] and EXTSS[3].
[0500] FIG. 70B is a schematic diagram showing a playback path 7010 in 2D
playback mode, playback path 7020 in L/R mode, and a playback path 7030 in depth
mode for the data block groups shown in FIG. 70A.
[0501] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 7010 in 2D playback mode, first the
base-view data block L1, which is second from the end of the first 3D extent block
7001, is read as the first 2D extent EXT2D[0], and reading of the immediately
subsequent depth map data block D2 and right-view data block R2 is skipped by a
first jump J2dL Next, a pair L2+(L3+L4)2d of the last base-view data block L2 in the
first 3D extent block 7001 and the immediately subsequent block exclusively for 2D
playback (L3+L4)2d is continuously read as the second 2D extent EXT2D[1]. A long
jump JLY occurs at the immediately subsequent layer boundary LB, and reading of
the eight data blocks D3, R3, L3SS, D4, R4, L4SS, D5, and R5, located at the top of
the second 3D extent block 7002, is skipped. Next, the third base-view data block
L5 in the second 3D extent block 7002 is read as the third 2D extent EXT2D[2].
[0502] The playback device 102 in L/R mode plays back the first file SS 244A
Accordingly, as shown by the playback path 7020 in L/R mode, first a pair R1+L1
of the top right-view data block R1 and the immediately subsequent base-view data
block L1 is read continuously as the first 3D extent EXTSS[0], and reading of the
[0504] The size Sext2D[1] of the 2D extent EXT2D[1] equals Sextl[1] + S2D, the sum
of the size Sexti[1] of the base-view data block L2 and the size S2d of the block
exclusively for 2D playback (L3+L4)2D. Accordingly, for seamless playback in 2D
playback mode, this sum Sextd1[1] + S2d should first satisfy expression 1. Next, the
number of sectors from the end of the block exclusively for 2D playback (L3+L4)2D
to the first 2D extent EXT2D[2] = L5 in the second 3D extent block 7002 should be
equal to or less than the maximum jump distance Sjump_max for the long jump JLY
specified in accordance with the capabilities of the 2D playback device.
[0505] On the other hand, for seamless playback in L/R mode, the sizes Sext2[1] and
Sext1[1] of the right-view data block R2 and base-view data block L2 located
immediately before the layer boundary LB should satisfy expressions 3 and 2. The
maximum jump time T^p,^ for the long jump JLY minus the layer switching time
should be substituted into the right-hand side of these expressions as the jump time
TjumP-3D- Next, the number of sectors from the end of the 3D extent EXTSS[1] to the
top of the first 3D extent EXTSS[2] in the second 3D extent block 7002 should be
equal to or less than the maximum jump distance S^p,^ for the long jump JLY
specified in accordance with the capabilities of the 3D playback device.
[0506] Only the base-view data block L2 located at the front of the 2D extent
EXT2D[1] is shared with the 3D extent EXTSS[1]. Accordingly, by appropriately
enlarging the size S2D of the block exclusively for 2D playback (L3+L4)2D, the size
Sexti[1] of the base-view data block L2 can be further limited while keeping the size
Sext2D[1] = Sexti[1] + S2D of the 2D extent EXT2D[1] constant. As a result, the size
Sexetl] of the right-view data block R2 can also be further limited.
[0507] Since the blocks exclusively for 3D playback L3SS and L4SS match the block
exclusively for 2D playback (L3+L4)2D bit for bit, enlarging the size S2D of the block
exclusively for 2D playback (L3+L4)2D enlarges the sizes of the right-view data
blocks R3 and R4 respectively located immediately before the blocks exclusively for
3D playback L3SS and L4SS. However, since there are two blocks exclusively for 3D
playback L3SS and L4SS as compared to one block exclusively for 2D playback
(L3+L4)2D, the sizes of the right-view data blocks R3 and R4 can be made
sufficiently smaller than the size of the right-view data block R2 located
immediately before the layer boundary LB shown in FIG. 67A. The capacity of the
read buffers 4021 and 4022 to be guaranteed in the playback device 102 in L/R
mode can thus be brought even closer to the minimum amount necessary for
seamless playback in L/R mode.
[0508] It is thus possible to set each data block in arrangement 2 to be a size at
which seamless playback of video images during a long jump is possible in both 2D
playback mode and L/R mode while keeping the read buffer capacity that is to be
guaranteed in the playback device 102 to the minimum necessary. The same is also
true for depth mode.
[0509] In arrangement 2, duplicate data of the block exclusively for 2D playback
(L3+L4)2D is divided into two blocks exclusively for 3D playback L3SS and L4ss-
Alternatively, the duplicate data may be divided into three or more blocks
exclusively for 3D playback.
[0510] [0-4] Arrangement 3
[0511] FIG. 71A is a schematic diagram showing a third example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101. Hereinafter, this arrangement is referred to as "arrangement
3". As shown by comparing FIG. 71A with FIG. 70A, arrangement 3 differs from
arrangement 2 in that the block exclusively for 2D playback (L2+L3)2d can be
accessed as a single 2D extent EXT2D[1]. The block exclusively for 2D playback
(L2+L3)2d matches bit-for-bit with the entirety of the blocks exclusively for 3D
playback L2SS+L3SS located immediately after the layer boundary LB. The other
characteristics of arrangement 3 are the same as arrangement 2, and thus a detailed
description thereof can be found in the description for arrangement 2.
[0512] The data blocks shown in FIG. 71A can be accessed as extents in either file
2D or file DEP, with the exception of the blocks exclusively for 3D playback L2SS
and L3SS. For example, the last base-view data block L1 in the first 3D extent block
7101, the block exclusively for 2D playback (L2+L3)2D, and the third base-view data
block L4 in the second 3D extent block 7102 can respectively be accessed as
individual 2D extents EXT2D[0], EXT2D[1], and EXT2D[2] in the file 2D 241.
[0513] For the data block groups shown in FIG. 71 A, cross-linking of AV stream
files is performed as follows. Each pair of contiguous right-view and base-view data
blocks R1+L1, R2+L2SS, R3+L3SS, and R4+L4 in the 3D extent blocks 7101 and
7102 can be accessed respectively as individual 3D extents EXTSS[0], EXTSS[1],
EXTSS[2], and EXTSS[3] in the first file SS 244A. In this case, with the exception
of the two 3D extents EXTSS[1] and EXTSS[2] immediately after the layer
boundary LB, the 3D extents EXTSS[0] and EXTSS[4] respectively share base-view
data blocks L1 and L4 with 2D extents EXT2D[0] and EXT2D[2]. On the other
hand, the block exclusively for 2D playback (L2+L3)2D can be accessed as part of
the 2D extent EXT2D[1]. Furthermore, the blocks exclusively for 3D playback L2SS
and L3SS can be accessed as part of the 3D extents EXTSS[1] and EXTSS[2].
[0514] FIG. 7IB is a schematic diagram showing a playback path 7110 in 2D
playback mode, playback path 7120 in L/R mode, and a playback path 7130 in depth
mode for the data block groups shown in FIG. 71 A.
[0515] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 7110 in 2D playback mode, the last
base-view data block L1 in the first 3D extent block 7101 is read as the first 2D
extent EXT2D[0]. Next, the immediately subsequent block exclusively for 2D
playback (L2+L3)2d is read as the second 2D extent EXT2D[1]. A long jump JLY
occurs at the immediately subsequent layer boundary LB, and reading of the eight
data blocks D2, R2, L2Ss, D3, R3, L3SS, D4, and R4, located at the top of the second
3D extent block 7102, is skipped. Next, the third base-view data block L4 in the
second 3D extent block 7102 is read as the third 2D extent EXT2D[2].
[0516] The playback device 102 in L/R mode plays back the first file SS 244A.
Accordingly, as shown by the playback path 7120 in L/R mode, first a pair R1+L1
of the top right-view data block R1 and the immediately subsequent base-view data
block L1 is read continuously as the first 3D extent EXTSS[0]. A long jump JLy
occurs immediately thereafter, and reading of the block exclusively for 2D playback
(L2+L3)2d and the top depth map data block D2 in the second 3D extent block 7102
is skipped. Next, the top right-view data block R2 in the second 3D extent block
7102 and the immediately subsequent block exclusively for 3D playback L2SS are
read continuously as the second 3D extent EXTSS[1], and reading of the
immediately subsequent depth map data block D3 is skipped by a first jump JLR1.
Similarly, the next right-view data block R3 and the immediately subsequent block
exclusively for 3D playback L3SS are read continuously as the third 3D extent
EXTSS[2], and reading of the immediately subsequent depth map data block D4 is
skipped by a second jump Jlr2. Furthermore, the next right-view data block R4 and
the immediately subsequent base-view data block L4 are read continuously as the
fourth 3D extent EXTSS[3].
[0517] As shown in FIG. 71B, in 2D playback mode, the block exclusively for 2D
playback (L2+L3)2D is read, whereas reading of the blocks exclusively for 3D
playback L2SS and L3SS is skipped. Conversely, in L/R mode, reading of the block
exclusively for 2D playback (L2+L3)2d is skipped, whereas the blocks exclusively
for 3D playback L2SS and L3Ss are read. However, since the block exclusively for
2D playback (L2+L3)2d matches the blocks exclusively for 3D playback L2SS and
L3SS bit-for-bit, the left-view video frames that are played back are the same in both
playback modes. In arrangement 3, the playback path 7110 in 2D playback mode
and the playback path 7120 in L/R mode are divided before and after the long jump
JLY in this way. Accordingly, the size Sext2D[1] of the 2D extent EXT2D[1] located
immediately before the layer boundary LB and the size Sext2[0] of the immediately
preceding right-view data block Rl can be determined separately as follows. The
same is also true for depth mode.
[0518] The sum of the sizes Sext2D[0]+Sext2D[1] of the 2D extents EXT2D[0] and
EXT2D[1] equals Sextl[0] + Sext2D[1], the sum of the size Sext1[0] of the base-view
data block L1 and the size Sext2D[1] of the block exclusively for 2D playback
(L2+L3)2D. Accordingly, for seamless playback in 2D playback mode, this sum
Sext1[0] + Sext2D[1] should first satisfy expression 1. Next, the number of sectors from
the end of the block exclusively for 2D playback (L2+L3)2d to the first 2D extent
EXT2D[2] = L4 in the second 3D extent block 7102 should be equal to or less than
the maximum jump distance Sjump_max for the long jump JLY specified in accordance
with the capabilities of the 2D playback device.
[0519] On the other hand, for seamless playback in L/R mode, the sizes Sext2[0] and
Sext1[0] of the right-view data block R1 and base-view data block L1 located
immediately before the layer boundary LB should satisfy expressions 3 and 2. The
maximum jump time Tjump_max for the long jump JLY minus the layer switching time
should be substituted into the right-hand side of these expressions as the jump time
TjumP-3D- Next, the number of sectors from the end of the 3D extent EXTSS[0] to the
top of the first 3D extent EXTSS[1] in the second 3D extent block 7102 should be
equal to or less than the maximum jump distance Sjump_max for the long jump JLY
specified in accordance with the capabilities of the 3D playback device.
[0520] The base-view data block Ll and the block exclusively for 2D playback
(L2+L3)2d belong to different 2D extents. Accordingly, by appropriately enlarging
the size Sext2D[1] of the block exclusively for 2D playback (L2+L3)2D, the size
Sext2D[0] = Sext1[0] of the base-view data block Ll can be further limited while
keeping the sum of the sizes Sext2D[0] + Sext2D[1] of the 2D extents EXT2D[0] and
EXT2D[1] constant. As a result, the size Sext2[0] of the right-view data block Rl can
also be further limited.
[0521] Since the blocks exclusively for 3D playback L2SS and L3Ss match the block
exclusively for 2D playback (L2+L3)2D bit for bit, enlarging the size Sext2D[1] of the
block exclusively for 2D playback (L2+L3)2d enlarges the sizes of the right-view
data blocks R2 and R3 respectively located immediately before the blocks
exclusively for 3D playback L2SS and L3Ss- However, since there are two blocks
exclusively for 3D playback L2SS and L3SS as compared to one block exclusively for
2D playback (L2+L3)2D, the sizes of the right-view data blocks R2 and R3 can be
made sufficiently smaller than the size of the right-view data block R2 located
immediately before the layer boundary LB shown in FIG. 67A. The capacity of the
read buffers 4021 and 4022 to be guaranteed in the playback device 102 in L/R
mode can thus be brought even closer to the minimum amount necessary for
seamless playback in L/R mode.
[0522] It is thus possible to set each data block in arrangement 3 to be a size at
which seamless playback of video images during a long jump is possible in both 2D
playback mode and L/R mode while keeping the read buffer capacity that is to be
guaranteed in the playback device 102 to the minimum necessary. The same is also
true for depth mode.
[0523] In arrangement 3, duplicate data of the block exclusively for 2D playback
(L2+L3)2D is divided into two blocks exclusively for 3D playback L2SS and L3SS.
Alternatively, the duplicate data may be provided as a single block exclusively for
3D playback or divided into three or more blocks exclusively for 3D playback.
Furthermore, the block exclusively for 2D playback may be accessible as two or
more extents in the file 2D.
[0524] In arrangement 3, the contiguous base-view data block L1 and the block
exclusively for 2D playback (L2+L3)2D may belong to different files 2D. In this case,
in the main path of the 2D playlist file, the CC is set to 5 or 6 between the Pis that
specify the playback section in each file 2D. Furthermore, the two 3D extent blocks
7101 and 7102 may belong to different files SS. Accordingly, in the main path of the
3D playlist file, the CC is set to 5 or 6 between the PIs that specify the playback
section in the file 2D that shares base-view data blocks with the files SS. On the
other hand, in the sub-path of the 3D playlist file, the SP connection condition (CC)
is set to 5 or 6 between the SUBPIs that specify the playback section in the file
DEP that shares dependent-view data blocks with the files SS.
[0525] [0-5] Arrangement 4
[0526] FIG. 72A is a schematic diagram showing a fourth example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101. Hereinafter, this arrangement is referred to as "arrangement
4". As shown by comparing FIG. 72A with FIG. 70A, arrangement 4 differs from
arrangement 2 in that a data block group in an interleaved arrangement that includes
the blocks exclusively for 3D playback L3Ss and L4SS is located immediately before
the layer boundary LB. The other characteristics of arrangement 4 are the same as
arrangement 2, and thus a detailed description thereof can be found in the
description for arrangement 2.
[0527] Blocks exclusively for 3D playback L3Ss and L4SS, along with depth map
data blocks D3 and D4 and right-view data blocks R3 and R4, are recorded in an
interleaved arrangement between the end L2 of the first 3D extent block 7201 and
the layer boundary LB. The content of each piece of stream data is continuous
between the data blocks D2, R2, and L2 located at the end of the first 3D extent
block 7201 and between the data blocks D5, R5, and L5 located at the top of the
second 3D extent block 7202. The blocks exclusively for 3D playback L3SS and L4SS
match the block exclusively for 2D playback (L3+L4)2D bit-for-bit.
[0528] The data blocks shown in FIG. 72A can be accessed as extents in either file
2D or file DEP, with the exception of the blocks exclusively for 3D playback L3Ss
and L4SS. For example, the base-view data block L1 second from the end of the first
3D extent block 7201, the pair of the last base-view data block L2 in the first 3D
extent block 7201 and the block exclusively for 2D playback (L3+L4)2d, and the
first base-view data block L5 in the second 3D extent block 7202 can respectively be
accessed as individual 2D extents EXT2D[0], EXT2D[1], and EXT2D[2] in the file
2D 241.
[0529] For the data block groups shown in FIG. 72A, cross-linking of AV stream
files is performed as follows. Each pair of contiguous right-view and base-view data
blocks R1+L1, R2+L2, R3+L3SS, R4+L4SS, and R5+L5 in the 3D extent blocks 7201
and 7202 and the interleaved arrangement immediately before the layer boundary
LB can be accessed respectively as individual 3D extents EXTSS[0], EXTSS[1],
EXTSS[2], EXTSS[3], and EXTSS[4] in the first file SS 244A. In this case, with the
exception of the two 3D extents EXTSS[2] and EXTSS[3] immediately before the
layer boundary LB, the 3D extents EXTSS[0], EXTSS[1], and EXTSS[4]
respectively share base-view data blocks L1, L2, and L5 with 2D extents EXT2D[0],
EXT2D[1], and EXT2D[2]. On the other hand, the block exclusively for 2D
playback (L3+L4)2D can be accessed as part of the 2D extent EXT2D[1].
Furthermore, the blocks exclusively for 3D playback L3Ss and L4SS can be accessed
as part of the 3D extents EXTSS[2] and EXTSS[3].
[0530] FIG. 72B is a schematic diagram showing a playback path 7210 in 2D
playback mode, playback path 7220 in L/R mode, and a playback path 7230 in depth
mode for the data block groups shown in FIG. 72A.
[0531] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 7210 in 2D playback mode, first the
base-view data block L1, which is second from the end of the first 3D extent block
7201, is read as the first 2D extent EXT2D[0], and reading of the immediately
subsequent depth map data block D2 and right-view data block R2 is skipped by a
first jump J2D1. Next, a pair L2+(L3+L4)2D of the last base-view data block L2 in the
first 3D extent block 7201 and the immediately subsequent block exclusively for 2D
playback (L3+L4)2D is continuously read as the second 2D extent EXT2D[1]. A long
jump JLY occurs immediately thereafter, and reading is skipped for the six data
blocks D3, R3, L3SS, D4, R4, and L4SS located immediately before the layer
boundary LB, as well as the two data blocks D5 and R5 located at the top of the
second 3D extent block 7202. Next, the first base-view data block L5 in the second
3D extent block 7202 is read as the third 2D extent EXT2D[2].
[0532] The playback device 102 in L/R mode plays back the first file SS 244A.
Accordingly, as shown by the playback path 7220 in L/R mode, first a pair R1+L1
of the top right-view data block Rl and the immediately subsequent base-view data
block L1 is read continuously as the first 3D extent EXTSS[0], and reading of the
immediately subsequent depth map data block D2 is skipped by a first jump JlrI .
Next, the second right-view data block R2 and the immediately subsequent
base-view data block L2 are read continuously as the second 3D extent EXTSS[1],
and reading of the immediately subsequent block exclusively for 2D playback
(L3+L4)2d and the depth map data block D3 is skipped by a second jump JEX.
Subsequently, the right-view data block R3 and the immediately subsequent block
exclusively for 3D playback L3SS are read continuously as the third 3D extent
EXTSS[2], and reading of the immediately subsequent depth map data block D4 is
skipped by a third jump Jlr3. Similarly, the next right-view data block R4 and the
immediately subsequent block exclusively for 3D playback L4SS are read
continuously as the fourth 3D extent EXTSS[3]. A long jump JLY occurs
immediately thereafter, and reading of the first depth map data block D5 in the
second 3D extent block 7202 is skipped. Furthermore, the next right-view data block
R5 and the immediately subsequent base-view data block L5 are read continuously
as the fifth 3D extent EXTSS[4].
[0533] As shown in FIG. 72B, in 2D playback mode, the block exclusively for 2D
playback (L3+L4)2D is read, whereas reading of the blocks exclusively for 3D
playback L3SS and L4SS is skipped. Conversely, in L/R mode, reading of the block
exclusively for 2D playback (L3+L4)2D is skipped, whereas the blocks exclusively
for 3D playback L3SS and L4SS are read. However, since the block exclusively for
2D playback (L3+L4)2d matches the blocks exclusively for 3D playback L3SS and
L4SS bit-for-bit, the left-view video frames that are played back are the same in both
playback modes. In arrangement 4, the playback path 7210 in 2D playback mode
and the playback path 7220 in L/R mode are divided immediately before the long
jump JLY in this way. Accordingly, the size Sext2d[1] of the 2D extent EXT2D[1]
located immediately before the layer boundary LB and the size Sext2[1] of the
immediately preceding right-view data block R2 can be determined separately as
follows. The same is also true for depth mode.
[0534] The size Sext2D[1] of the 2D extent EXT2D[1] equals Sext1[1] + S2D, the sum
of the size Sextl[1] of the base-view data block L2 and the size S2d of the block
exclusively for 2D playback (L3+L4)2D. Accordingly, for seamless playback in 2D
playback mode, this sum Sext1[1] + S2d should first satisfy expression 1. Next, the
number of sectors from the end of the block exclusively for 2D playback (L3+L4)2D
to the first 2D extent EXT2D[2] = L5 in the second 3D extent block 7202 should be
equal to or less than the maximum jump distance Sjump_max for the long jump JLY
specified in accordance with the capabilities of the 2D playback device.
[0535] On the other hand, for seamless playback in L/R mode, the sizes Sext2[1] and
Sext1[1] °f the right-view data block R2 and base-view data block L2 located
immediately before the block exclusively for 2D playback (L3+L4)2D should satisfy
expressions 3 and 2. The value of the maximum jump time Tjump_max that is to be
substituted into the right-hand side of these expressions as the jump time Tjump-3d
should correspond, as per the table in FIG. 57, to the number of sectors for the jump
distance of the second jump Jex minus the size of the block exclusively for 2D
playback (L3+L4)2D. In other words, the sizes of the data blocks R2 and L2
substantially equal the minimum extent size calculated supposing that "the
immediately subsequent block exclusively for 2D playback (L3+L4)2D is removed,
and the depth map data block D3 follows thereafter". Next, the sizes of the
right-view data block R3 and block exclusively for 3D playback L3SS located
immediately after the block exclusively for 2D playback (L3+L4)2D should satisfy
expressions 3 and 2. In this case, the jump time Tjump-3D that should be substituted
into the right-hand side of these expressions is the maximum jump time Tjump_max of
the third jump Jlr3. However, rather than the size of the right-view data block R4,
the size of the first right-view data block R5 in the second 3D extent block 7202 is
substituted into the right-hand side of expression 2 as the size Sext2[n+1] of the next
right-view extent. In other words, the sizes of the data blocks R3 and L3SS
substantially equal the minimum extent size calculated supposing that "the second
3D extent block 7202 follows immediately thereafter". The sizes of the data blocks
D4, R4, and L4SS located immediately before the layer boundary LB thus do not
have to satisfy expressions 2-5. Furthermore, the number of sectors from the end of
the block exclusively for 3D playback L4SS to the top of the next 3D extent
EXTSS[4] should be equal to or less than the maximum jump distance Sjump_max for
the long jump JLY specified in accordance with the capabilities of the 3D playback
device.
[0536] Only the base-view data block L2 located at the front of the 2D extent
EXT2D[1] is shared with the 3D extent EXTSS[1]. Accordingly, by appropriately
enlarging the size S2d of the block exclusively for 2D playback (L3+L4)2D, the size
Sext1[1] of the base-view data block L2 can be further limited while keeping the size
Sext2D[1] = Sext1[1] + S2d of the 2D extent EXT2D[1] constant. As a result, the size
Sext2[1] of the right-view data block R2 can also be further limited.
[0537] Since the blocks exclusively for 3D playback L3Ss and L4Ss match the block
exclusively for 2D playback (L3+L4)2d bit for bit, enlarging the size S2D of the block
exclusively for 2D playback (L3+L4)2D enlarges the sizes of the right-view data
blocks R3 and R4 respectively located immediately before the blocks exclusively for
3D playback L3SS and L4SS. However, since there are two blocks exclusively for 3D
playback L3SS and L4Ss as compared to one block exclusively for 2D playback
(L3+L4)2D, the sizes of the right-view data blocks R3 and R4 can be made
sufficiently smaller than the size of the right-view data block R2 located
immediately before the layer boundary LB shown in FIG. 6 7A.
[0538] It is thus possible to set each data block in arrangement 4 to be a size at
which seamless playback of video images during a long jump is possible in both 2D
playback mode and L/R mode while keeping the read buffer capacity that is to be
guaranteed in the playback device 102 to the minimum necessary. The same is also
true for depth mode.
[0539] However, since the sizes of the data blocks D4, R4, and L4SS located
immediately before the layer boundary LB in arrangement 4 do not satisfy
expressions 2-5, the buffer margin amounts UL1 and UL2 to be maintained in the
read buffers 4021 and 4022 are not evaluated via expressions 8 and 9, but rather as
follows.
[0540] FIG. 73A is a graph showing changes in the data amount DA1 stored in the
first read buffer 4021 during a read period of data blocks in accordance with the
playback path 7220 in L/R mode shown in FIG. 72B. At the first time TA shown in
FIG. 73A, reading of the last base-view data block L2 in the first 3D extent block
7201 starts. Afterwards, at the second time TB, reading of the first base-view data
block L5 in the second 3D extent block 7202 starts. Expression 15 yields the
maximum value DR1 of the data amount that can be read from the first read buffer
4021 from the first time TA until the second time TB.
[0541]

[0542] In this expression, the jump times Tjump-ex, Tjump[2], and Tjump-LY respectively
represent the jump times for the second jump Jlr2, the third jump Jlr3, and the long
jump JLY. Furthermore, the sizes Sext2[2] and Sext2[4] of right-view extents
respectively represent the sizes of the right-view data block R3 located immediately
after the block exclusively for 2D playback (L3+L4)2d and the first right-view data
block R5 in the second 3D extent block 7202. Note that for the purpose of seeking
the maximum possible value of the necessary buffer margin amount, the sizes of the
data blocks D4, R4, and L4SS located immediately before the layer boundary LB are
assumed to be zero.
[0543] On the other hand, expression 16 yields the minimum value DI1 of the data
amount that can be stored in the first read buffer 4021 from the first time TA until
the second time TB.
[0544]

[0545] In this expression, the sizes Sext1[1] and Sext1[2] of base-view extents
respectively represent the sizes of the last base-view data block L2 in the first 3D
extent block 7201 and the block exclusively for 3D playback L3SS located
immediately after the block exclusively for 2D playback (L3+L4)2d-
[0546] To prevent underflow in the first read buffer 4021 during the long jump JLY,
the stored data amount DA1 should be equal to or greater than zero at the second
time TB. Accordingly, the buffer margin amount UL1 should at least be the
difference between the maximum value DR1 of the data amount that can be read
from the first read buffer 4021 from the first time TA until the second time TB and
the minimum value DI1 of the data amount that can be stored in the first read buffer
4021 in the same period. That is, the buffer margin amount UL1 is represented in
expression 17.
[0547]
UL1>DR1-DI1

[0548] The jump time Tjump in this expression equals the maximum jump time
Tjump_max, as per the table in FIG. 57, corresponding to the number of sectors of the
jump distance for the second jump Jex minus the size of the block exclusively for 2D
playback (L3+L4)2D. In this case, since the sizes Sext[1] and Sext1[2] of the base-view
data blocks L2 and L3Ss satisfy expression 2, the second and third terms in
expression 16 are both equal to or less than zero. Therefore, the value of the buffer
margin amount UL1 should at least satisfy expression 18.

[0550] FIG. 73B is a graph showing changes in the data amount DA2 stored in the
second read buffer 4022 during a read period of data blocks in accordance with the
playback path 7220 in L/R mode shown in FIG. 72B. At the third time TC shown in
FIG. 73B, reading of the last right-view data block R2 in the first 3D extent block
7201 starts. Afterwards, at the fourth time TD, reading of the first right-view data
block R5 in the second 3D extent block 7202 starts.
[0551] The buffer margin amount UL2 should at least be the difference between the
maximum value of the data amount that can be read from the second read buffer
4022 from the third time TC until the fourth time TD and the minimum value of the
data amount that can be stored in the second read buffer 4022 in the same period.
Accordingly, since the sizes of the right-view data blocks R2 and R3 satisfy
expression 3, the value of the buffer margin amount UL2 should at least satisfy
expression 19.
[0552]

[0553] In depth mode as well, for the same reasons the values of the buffer margin
amounts UL1 and UL2 in the read buffers 4021 and 4022 should at least fulfill
expressions 20 and 21.
[0554]

[0555] In these expressions, the jump times Tjump-EX and Tjump respectively represent
the jump times of the jump JEX to skip reading of the block exclusively for 2D
playback (L3+L4)2d and the jump JLD3 to skip reading of the right-view data block
R4 located immediately before the layer boundary LB.
[0556] In arrangement 4, duplicate data of the block exclusively for 2D playback
(L3+L4)2D is divided into two blocks exclusively for 3D playback L3SS and L4SS.
Alternatively, the duplicate data may be provided as a single block exclusively for
3D playback or divided into three or more blocks exclusively for 3D playback.
Furthermore, the block exclusively for 2D playback may be accessible as two or
more extents in the file 2D.
[0557] In arrangement 4, a third 3D extent block differing from the second 3D
extent block 7202 may follow after the end of the first 3D extent block 7201. FIG.
74 is a schematic diagram showing a third 3D extent block 7401, the file 2D #2
7410 and the file SS #2 7420 that share the base-view data blocks therein, and
playlist files 221, 222, 7430, and 7440 that define playback paths for each of the
files 241, 244A, 7410, and 7420.
[0558] The first base-view data block Lx in the third 3D extent block 7401 is
recorded at a distance from the end of the block exclusively for 2D playback
(L3+L4)2d that is equal to or less than the maximum jump distance Sjump_max for the
long jump JLY specified in accordance with the capabilities of the 2D playback
device. Furthermore, the top of the third 3D extent block 7401 is recorded at a
distance from the end of the first 3D extent block 7201 that is equal to or less than
the maximum jump distance Sjump_max for the long jump JLy specified in accordance
with the capabilities of the 3D playback device. The sizes of the two types of
dependent-view data blocks Dx and Rx located at the top of the third 3D extent
block 7401 are set, in expressions 4 and 2, so as to be compatible with the size of the
block exclusively for 3D playback L3Ss located immediately after the block
exclusively for 2D playback (L3+L4)2D-
[0559] In the main path of the 2D playlist file #2 7430, PI #1 specifies the playback
section in the file 2D 241 corresponding to the first 3D extent block 7201. On the
other hand, PI #2 specifies the playback section in the file 2D #2 7410
corresponding to the third 3D extent block 7401. Furthermore, a CC value of 5 or 6
is set in PI #2 with regards to PI #1. Accordingly, during playback of the 2D playlist
file #2 7430, 2D video images are seamlessly played back from the third 3D extent
block 7401 subsequently after the first 3D extent block 7201.
[0560] Similarly in the main path of the 3D playlist file #2 7440, the CC is set to 5
or 6 between the Pis that specify the playback section in each file 2D. On the other
hand, in the sub-path of the 3D playlist file #2, the SUB_PI #1 and #2 respectively
specify playback sections in the file DEP that shares dependent-view data blocks
with each file SS. Furthermore, the SPCC is set to 5 or 6 between these SUB_PIs.
Accordingly, during playback of the 3D playlist file #2 7440, 3D video images are
seamlessly played back from the third 3D extent block 7401 subsequently after the
first 3D extent block 7201.
[0561] [0-6] Arrangement 5
[0562] FIG. 75A is a schematic diagram showing a fifth example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101. Hereinafter, this arrangement is referred to as "arrangement
5". As shown by comparing FIG. 75A with FIG. 71 A, arrangement 5 differs from
arrangement 3 in that a data block group in an interleaved arrangement that includes
the blocks exclusively for 3D playback L2SS, L3SS, and L4SS is located immediately
before the block exclusively for 2D playback (L2+L3+L4)2D. The other
characteristics of arrangement 5 are the same as arrangement 3, and thus a detailed
description thereof can be found in the description for arrangement 3.
[0563] Blocks exclusively for 3D playback L2SS, L3SS, and L4SS, along with depth
map data blocks D2, D3, and D4 and right-view data blocks R2, R3, and R4, are
recorded in an interleaved arrangement immediately after the end L1 of the first 3D
extent block 7501. The content of each piece of stream data is continuous between
the data blocks D2, R2, and L2 located at the end of the first 3D extent block 7501
and between the data blocks D5, R5, and L5 located at the top of the second 3D
extent block 7502. A block exclusively for 2D playback (L2+L3+L4)2d is recorded
between the block exclusively for 3D playback L4SS and the layer boundary LB. The
blocks exclusively for 3D playback L2SS, L3Ss, and L4SS match the block exclusively
for 2D playback (L2+L3+L4)2D bit-for-bit.
[0564] The data blocks shown in FIG. 75A can be accessed as extents in either file
2D or file DEP, with the exception of the blocks exclusively for 3D playback L2SS,
L3SS, and L4SS. For example, the last base-view data block L1 in the first 3D extent
block 7501, the block exclusively for 2D playback (L2+L3+L4)2D, and the first
base-view data block L5 in the second 3D extent block 7502 can respectively be
accessed as individual 2D extents EXT2D[0], EXT2D[1], and EXT2D[2] in the file
2D 241.
[0565] For the data block groups shown in FIG. 75A, cross-linking of AV stream
files is performed as follows. Each pair of contiguous right-view and base-view data
blocks R1+L1, R2+L2SS, R3+L3SS, R4+L4SS, and R5+L5 in the 3D extent blocks
7501 and 7502 and the interleaved arrangement immediately before the layer
boundary LB can be accessed respectively as individual 3D extents EXTSS[0],
EXTSS[1], EXTSS[2], EXTSS[3], and EXTSS[4] in the first file SS 244A. In this
case, with the exception of the 3D extents EXTSS[1], EXTSS[2], and EXTSS[3]
that include the blocks exclusively for 3D playback L2SS, L3Ss, and L4SS, the 3D
extents EXTSS[0] and EXTSS[4] respectively share base-view data blocks L1 and
L5 with 2D extents EXT2D[0] and EXT2D[2]. On the other hand, the block
exclusively for 2D playback (L2+L3+L4)2d can be accessed as part of the 2D extent
EXT2D[1]. Furthermore, the blocks exclusively for 3D playback L2SS, L3SS, and
L4Ss can be accessed as part of the 3D extents EXTSSfl], EXTSS[2], and
EXTSS[3].
[0566] FIG. 75B is a schematic diagram showing a playback path 7510 in 2D
playback mode, playback path 7520 in L/R mode, and a playback path 7530 in depth
mode for the data block groups shown in FIG. 75 A.
[0567] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 7510 in 2D playback mode, the last
base-view data block L1 in the first 3D extent block 7501 is read as the first 2D
extent EXT2D[0], and reading of the immediately subsequent nine data blocks D2,
R2, L2SS, D3, R3, L3Ss, D4, R4, and L4SS is skipped by a jump J2D1- Next, the block
exclusively for 2D playback (L2+L3+L4)2d immediately before the layer boundary
LB is read as the second 2D extent EXT2D[1]. A long jump JLY occurs immediately
thereafter, and reading of the two data blocks D5 and R5 located at the top of the
second 3D extent block 7502 is skipped. Subsequently, the first base-view data
block L5 in the second 3D extent block 7502 is read as the third 2D extent
EXT2D[2].
[0568] The playback device 102 in L/R mode plays back the first file SS 244A.
Accordingly, as shown by the playback path 7520 in L/R mode, first a pair R1+L1
of the top right-view data block R1 and the immediately subsequent base-view data
block L1 is read continuously as the first 3D extent EXTSS[0], and reading of the
immediately subsequent depth map data block D2 is skipped by a first jump JlrI.
Next, the second right-view data block R2 and the immediately subsequent block
exclusively for 3D playback L2SS are read continuously as the second 3D extent
EXTSS[1], and reading of the immediately subsequent depth map data block D3 is
skipped by a second jump Jlr2. Subsequently, the right-view data block R3 and the
immediately subsequent block exclusively for 3D playback L3SS are read
continuously as the third 3D extent EXTSS[1], and reading of the immediately
subsequent depth map data block D4 is skipped by a third jump Jlr3. Similarly, the
right-view data block R4 and the immediately subsequent block exclusively for 3D
playback L4SS are read continuously as the fourth 3D extent EXTSS[3]. A long jump
JLY occurs immediately thereafter, and reading of the immediately subsequent block
exclusively for 2D playback (L2+L3+L4)2D and of the first depth map data block D5
in the second 3D extent block 7502 is skipped. Furthermore, the next right-view data
block R5 and the immediately subsequent base-view data block L5 are read
continuously as the fifth 3D extent EXTSS[4].
[0569] As shown in FIG. 75B, in 2D playback mode, the block exclusively for 2D
playback (L2+L3+L4)2D is read, whereas reading of the blocks exclusively for 3D
playback L2SS, L3Ss, and L4SS is skipped. Conversely, in L/R mode, reading of the
block exclusively for 2D playback (L2+L3+L4)2D is skipped, whereas the blocks
exclusively for 3D playback L2SS, L3SS, and L4SS are read. However, since the block
exclusively for 2D playback (L2+L3+L4)2d matches the blocks exclusively for 3D
playback L2SS, L3SS, and L4SS bit-for-bit, the left-view video frames that are played
back are the same in both playback modes. In arrangement 5, the playback path
7510 in 2D playback mode and the playback path 7520 in L/R mode are divided
immediately before the long jump JLY in this way. Accordingly, the size of the block
exclusively for 2D playback (L2+L3+L4)2D, i.e. the size Sext2d[1] of the 2D extent
EXT2D[1], and the size Sext2[0] of the last right-view data block R1 in the first 3D
extent block 7501 can be determined separately as follows. The same is also true for
depth mode.
[0570] The block exclusively for 2D playback (L2+L3+L4)2D and the last base-view
data block L1 in the first 3D extent block 7501 belong to different 2D extents
EXT2D[0] and EXT2D[1]. Accordingly, for seamless playback in 2D playback
mode, the size Sext2D[1] of the block exclusively for 2D playback (L2+L3+L4)2D
should satisfy expression 1. Next, the number of sectors from the end of the block
exclusively for 2D playback (L2+L3+L4)2D to the first 2D extent EXT2D[2] = L5 in
the second 3D extent block 7502 should be equal to or less than the maximum jump
distance Sjump_max for the long jump JLY specified in accordance with the capabilities
of the 2D playback device. Furthermore, the size Sext2D[0] of the base-view data
block L1 should fulfill expression 1. The maximum jump time Tjump_max for the jump
J2d1 should be substituted into the right-hand side of this expression as the jump
time Tjump-2D.
[0571] On the other hand, for seamless playback in L/R mode, the sizes Sext2[0] and
Sext1[0] of the last right-view data block R1 and base-view data block L1 in the first
3D extent block 7501 should satisfy expressions 3 and 2. The maximum jump time
Tjump_max for the first jump Jlr1 should be substituted into the right-hand side of these
expressions as the jump time Tjump-3d. Next, the sizes of the data blocks R2, L2SS, R3,
and L3SS located immediately after the first 3D extent block 7501 should satisfy
expressions 3 and 2. However, with regards to the size of the block exclusively for
3D playback L3SS located last among these blocks, rather than the size of the
right-view data block R4 located immediately after the block exclusively for 3D
playback L3SS, the size of the first right-view data block R5 in the second 3D extent
block 7502 is substituted into the right-hand side of expression 2 as the size
Sext2[n+1] of the next right-view extent. In other words, the sizes of the data blocks
R3 and L3Ss substantially equal the minimum extent size calculated supposing that
"the second 3D extent block 7502 follows immediately thereafter". The sizes of the
data blocks D4, R4, and L4SS located immediately before the layer boundary LB
thus do not have to satisfy expressions 2-5. Furthermore, the number of sectors from
the end of the block exclusively for 3D playback L4SS to the top of the next 3D
extent EXTSS[4] should be equal to or less than the maximum jump distance
Sjump_max for the long jump JLY specified in accordance with the capabilities of the 3D
playback device.
[0572] As in the above description, the size of the last base-view data block L1 in
the first 3D extent block 7501 can be set independently of the size of the block
exclusively for 2D playback (L2+L3+L4)2D. Accordingly, the size Sext1[0] of the
base-view data block L1 can be further limited while keeping the size Sext2d[1] of the
block exclusively for 2D playback (L2+L3+L4)2D constant. As a result, the size
Sext2[0] of the right-view data block R1 can also be further limited.
[0573] Since the entirety of the blocks exclusively for 3D playback L2SS+L3SS+L4SS
match the block exclusively for 2D playback (L2+L3+L4)2D bit for bit, enlarging the
size of the block exclusively for 2D playback (L2+L3+L4)2D enlarges the sizes of
the right-view data blocks R2, R3, and R4 respectively located immediately before
the blocks exclusively for 3D playback L2SS, L3SS, and L4SS. However, since there
are three blocks exclusively for 3D playback L2SS, L3SS, and L4SS as compared to
one block exclusively for 2D playback (L2+L3+L4)2D, the sizes of the right-view
data blocks R2, R3, and R4 can be made sufficiently smaller than the size of the
right-view data block R2 located immediately before the layer boundary LB shown
in FIG. 67A.
[0574] It is thus possible to set each data block in arrangement 5 to be a size at
which seamless playback of video images during a long jump is possible in both 2D
playback mode and L/R mode while keeping the read buffer capacity that is to be
guaranteed in the playback device 102 to the minimum necessary. The same is also
true for depth mode.
[0575] However, for seamless playback of 2D video images from the data block
groups in arrangement 5, the number of sectors from the base-view data block L1
located at the end of the first 3D extent block 7501 to the top of the block
exclusively for 2D playback (L2+L3+L4)2D has to be kept equal to or less than the
maximum jump distance Sjump_max for the jump J2D1 specified in accordance with the
capabilities of the 2D playback device. The size of the right-view data block R1
located immediately before the base-view data block L1 thus has to be kept small. If
this condition is not met, then instead of arrangement 5, another arrangement such as
arrangement 4 should be used. As is clear from expression 1, the minimum extent
size of 2D extents depends on the system rate for the file 2D, which equals 188/192
times the maximum value Rmax2D of the mean transfer rate Rext2D. Accordingly,
during the authoring process of the file 2D, the above condition may be determined
to be met when the system rate is equal to or less than a predetermined threshold.
[0576] Furthermore, since the sizes of the data blocks D4, R4, and L4SS located
immediately before the layer boundary LB in arrangement 5 do not satisfy
expressions 2-5, the buffer margin amounts UL1 and UL2 to be maintained in the
read buffers 4021 and 4022 are not evaluated via expressions 8 and 9, but rather as
follows.
[0577] FIG. 76A is a graph showing changes in the data amount DA1 stored in the
first read buffer 4021 during a read period of data blocks in accordance with the
playback path 7520 in L/R mode shown in FIG. 75B. At the first time TE shown in
FIG. 76A, reading of the second block exclusively for 3D playback L3SS starts.
Afterwards, at the second time TF, reading of the first base-view data block L5 in
the second 3D extent block 7502 starts. Expression 22 yields the maximum value
DR1 of the data amount that can be read from the first read buffer 4021 from the
first time TE until the second time TF.
[0578]

[0579] In this expression, the jump times Tjump and Tjump-Ly respectively represent the
jump times for the third jump JLr3 and the long jump JLY. Furthermore, the size
Sext2[4] of the right-view extent represents the size of the first right-view data block
R5 in the second 3D extent block 7502. Note that for the purpose of seeking the
maximum possible value of the necessary buffer margin amount, the sizes of the
data blocks D4, R4, and L4SS located immediately before the layer boundary LB are
assumed to be zero.
[0580] On the other hand, expression 23 yields the minimum value DI1 of the data
amount that can be stored in the first read buffer 4021 from the first time TE until
the second time TF.
[0581]

[0582] In this expression, the size Sext1[2] of the base-view extent represents the size
of the second block exclusively for 3D playback L3SS.
[0583] To prevent underflow in the first read buffer 4021 during the long jump JLY,
the stored data amount DA1 should be equal to or greater than zero at the second
time TF. Accordingly, the buffer margin amount UL1 should at least be the
difference between the maximum value DR1 of the data amount that can be read
from the first read buffer 4021 from the first time TE until the second time TF and
the minimum value DI1 of the data amount that can be stored in the first read buffer
4021 in the same period. That is, the buffer margin amount UL1 is represented in
expression 24.
[0584]
UL1>DR1-DI1
[0585] In this case, since the size Sext1[2] of the second block exclusively for 3D
playback L3SS satisfies expression 2, the second term in expression 24 is equal to or
less than zero. Therefore, the value of the buffer margin amount UL1 should at least
satisfy expression 25.
[0586]

[0587] FIG. 76B is a graph showing changes in the data amount DA2 stored in the
second read buffer 4022 during a read period of data blocks in accordance with the
playback path 7520 in L/R mode shown in FIG. 75B. At the third time TG shown in
FIG. 76B, reading of the right-view data block R3 located immediately before the
second block exclusively for 3D playback L3SS starts. Afterwards, at the fourth time
TH, reading of the first right-view data block R5 in the second 3D extent block 7502
starts.
[0588] The buffer margin amount UL2 should at least be the difference between the
maximum value of the data amount that can be read from the second read buffer
4022 from the third time TG until the fourth time TH and the minimum value of the
data amount that can be stored in the second read buffer 4022 in the same period.
Accordingly, since the size of the right-view data block R3 satisfies expression 3,
the value of the buffer margin amount UL2 should at least satisfy expression 26.
[0589]
[0590] In depth mode as well, for the same reasons the values of the buffer margin
amounts UL1 and UL2 in the read buffers 4021 and 4022 should at least fulfill
expressions 27 and 28.
[0591]

[0592] In these expressions, the jump time Tjump represents the jump time of the
jump Jld3 to skip reading of the right-view data block R4 located immediately
before the layer boundary LB.
[0593] As can be seen by comparing expressions 25 and 26 with expressions 19 and
20, the buffer margin amounts UL1 and UL2 in L/R mode are smaller in
arrangement 5 than in arrangement 4. Accordingly, as is clear from expressions
12-14 in modification [N], it is possible to reduce the minimum capacity of the read
buffers 4021 and 4022 in L/R mode.
[0594] In arrangement 5, duplicate data of the block exclusively for 2D playback
(L2+L3+L4)2D is divided into three blocks exclusively for 3D playback L2SS, L3Ss,
and L4SS. Alternatively, the duplicate data may be provided as a single block
exclusively for 3D playback or divided into four or more blocks exclusively for 3D
playback. Furthermore, the block exclusively for 2D playback may be accessible as
two or more extents in the file 2D.
[0595] In arrangement 5, the base-view data blocks in the 3D extent block 7501 may
belong to a different file 2D than the base-view data blocks in the 3D extent block
7502. In this case, in the main path of the 2D playlist file, the CC is set to 5 or 6
between the PIs that specify the playback section in each file 2D. Furthermore, the
two 3D extent blocks 7501 and 7502 belong to different files SS. Accordingly, in the
main path of the 3D playlist file, the CC is set to 5 or 6 between the PIs that specify
the playback section in the file 2D that shares base-view data blocks with the files
SS. On the other hand, in the sub-path of the 3D playlist file, the SP connection
condition (CC) is set to 5 or 6 between the SUB_PIs that specify the playback
section in the file DEP that shares dependent-view data blocks with the files SS.
[0596] [0-7] Arrangement 6
[0597] FIG. 77A is a schematic diagram showing a sixth example of a physical
arrangement of data block groups recorded before and after a layer boundary LB on
the BD-ROM disc 101. Hereinafter, this arrangement is referred to as "arrangement
6". As shown by comparing FIG. 77A with FIG. 72A, arrangement 6 differs from
arrangement 4 in that, in the pairs of a right-view data block and a depth map data
block R3+D3 and R4+D4, respectively located immediately before the blocks
exclusively for 3D playback L3Ss and L4SS, the right-view data blocks and depth
map data blocks are in reverse order. The other characteristics of arrangement 6 are
the same as arrangement 4, and thus a detailed description thereof can be found in
the description for arrangement 4.
[0598] For the data block groups shown in FIG. 77A, cross-linking of AV stream
files is performed as follows. Each pair of contiguous right-view and base-view data
blocks R1+L1, R2+L2, and R5+L5 in the 3D extent blocks 7701 and 7702 can be
accessed respectively as individual 3D extents EXTSS[0], EXTSS[1], and
EXTSS[6] in the first file SS 244A. In this case, the 3D extents EXTSS[0],
EXTSS[1], and EXTSS[6] respectively share the base-view data blocks L1, L2, and
L5 with the 2D extents EXT2D[0], EXT2D[1], and EXT2D[2]. On the other hand,
the right-view data blocks R3 and R4 and the blocks exclusively for 3D playback
L3Ss and L4SS, located within the interleaved arrangement immediately before the
layer boundary LB, can respectively be accessed as individual 3D extents EXTSS[2],
EXTSS[3], EXTSS[4], and EXTSS[5] in the first file SS 244A. Furthermore, the
block exclusively for 2D playback (L3+L4)2d can be accessed as an individual 2D
extent EXT2D[1].
[0599] FIG. 77B is a schematic diagram showing a playback path 7710 in 2D
playback mode, playback path 7720 in L/R mode, and a playback path 7730 in depth
mode for the data block groups shown in FIG. 77A.
[0600] The playback device 102 in 2D playback mode plays back the file 2D 241.
Accordingly, as shown by the playback path 7710 in 2D playback mode, first the
base-view data block L1, which is second from the end of the first 3D extent block
7701, is read as the first 2D extent EXT2D[0], and reading of the immediately
subsequent depth map data block D2 and right-view data block R2 is skipped by a
first jump J2D1. Next, a pair L2+(L3+L4)2D of the last base-view data block L2 in the
first 3D extent block 7701 and the immediately subsequent block exclusively for 2D
playback (L3+L4)2d is continuously read as the second 2D extent EXT2D[1]. A long
jump JLY occurs immediately thereafter, and reading is skipped for the six data
blocks R3, D3, L3SS, R4, D4, and L4SS located immediately before the layer
boundary LB, as well as the two data blocks D5 and R5 located at the top of the
second 3D extent block 7702. Next, the first base-view data block L5 in the second
3D extent block 7702 is read as the third 2D extent EXT2D[2].
[0601] The playback device 102 in L/R mode plays back the first file SS 244A.
Accordingly, as shown by the playback path 7720 in L/R mode, first a pair R1+L1
of the top right-view data block R1 and the immediately subsequent base-view data
block L1 is read continuously as the first 3D extent EXTSS[0], and reading of the
immediately subsequent depth map data block D2 is skipped by a first jump JlrI.
Next, the second right-view data block R2 and the immediately subsequent
base-view data block L2 are read continuously as the second 3D extent EXTSS[1],
and reading of the immediately subsequent block exclusively for 2D playback
(L3+L4)2D is skipped by a second jump JEX. Subsequently, the right-view data block
R3 is read as the third 3D extent EXTSS[2], and reading of the immediately
subsequent depth map data block D3 is skipped by a third jump Jlr3. Furthermore,
the immediately subsequent block exclusively for 3D playback L3SS is read as the
fourth 3D extent EXTSS[3], and the next right-view data block R4 is read as the
fifth 3D extent EXTSS[4]. Reading of the immediately subsequent depth map data
block D4 is skipped by a fourth jump Jlr4. The immediately subsequent block
exclusively for 3D playback L4SS is read as the sixth 3D extent EXTSS[5]. A long
jump JLY occurs immediately thereafter, and reading of the first depth map data
block D5 in the second 3D extent block 7702 is skipped. Furthermore, the next
right-view data block R5 and the immediately subsequent base-view data block L5
are read continuously as the seventh 3D extent EXTSS[6].
[0602] As shown in FIG. 77B, the playback path 7710 in 2D playback mode and the
playback path 7720 in L/R mode are divided immediately before the long jump JLY
in arrangement 6 in the same way as in arrangement 4. Accordingly, the size
Sext2D[1] of the 2D extent EXT2D[1] located immediately before the layer boundary
LB and the size Sext2[1] of the immediately preceding right-view data block R2 can
be determined separately as follows. The same is also true for depth mode.
[0603] The size Sext2D[1] of the 2D extent EXT2D[1] equals Sextl[1] + S2D, the sum
of the size Sextl[1] of the base-view data block L2 and the size S2d of the block
exclusively for 2D playback (L3+L4)2D. Accordingly, for seamless playback in 2D
playback mode, this sum Sext1[1] + S2d should first satisfy expression 1. Next, the
number of sectors from the end of the block exclusively for 2D playback (L3+L4)2D
to the first 2D extent EXT2D[2] = L5 in the second 3D extent block 7702 should be
equal to or less than the maximum jump distance Sjump_max for the long jump JLY
specified in accordance with the capabilities of the 2D playback device.
[0604] On the other hand, for seamless playback in L/R mode, the sizes Sext2[1] and
Sext1[1] of the right-view data block R2 and base-view data block L2 located
immediately before the block exclusively for 2D playback (L3+L4)2D should satisfy
expressions 3 and 2. The zero sector transition time Tjump-0 should be substituted into
the right-hand side of these expressions as the jump time Tjump-3d. In other words, the
sizes of the data blocks R2 and L2 substantially equal the minimum extent size
calculated supposing that "the immediately subsequent block exclusively for 2D
playback (L3+L4)2D is removed, and the right-view data block R3 follows
thereafter". Next, the sizes of the right-view data block R3 and block exclusively for
3D playback L3SS located immediately after the block exclusively for 2D playback
(L3+L4)2D should satisfy expressions 5 and 4, replacing the depth-map data block in
these expressions with the right-view data block. However, rather than the size of
the right-view data block R4, the size of the first right-view data block R5 in the
second 3D extent block 7702 is substituted into the right-hand side of expression 4
as the size Sext2[n+1] of the next right-view extent. In other words, the sizes of the
data blocks R3 and L3Ss substantially equal the minimum extent size calculated
supposing that "the second 3D extent block 7702 follows immediately thereafter".
The sizes of the data blocks R4, D4, and L4Ss located immediately before the layer
boundary LB thus do not have to satisfy expressions 2-5. Furthermore, the number
of sectors from the end of the block exclusively for 3D playback L4SS to the top of
the next 3D extent EXTSS[4] should be equal to or less than the maximum jump
distance Sjump_max for the long jump JLY specified in accordance with the capabilities
of the 3D playback device.
[0605] Only the base-view data block L2 located at the front of the 2D extent
EXT2D[1] is shared with the 3D extent EXTSS[1]. Accordingly, by appropriately
enlarging the size S2d of the block exclusively for 2D playback (L3+L4)2D, the size
Sext1[1] of the base-view data block L2 can be further limited while keeping the size
Sext2D[1] = Sext1[1] + S2D of the 2D extent EXT2D[1] constant. As a result, the size
Sext2[1] of the right-view data block R2 can also be further limited.
[0606] Since the blocks exclusively for 3D playback L3SS and L4SS match the block
exclusively for 2D playback (L3+L4)2d bit for bit, enlarging the size S2d of the block
exclusively for 2D playback (L3+L4)2D enlarges the sizes of the right-view data
blocks R3 and R4 respectively located immediately before the blocks exclusively for
3D playback L3SS and L4SS. However, since there are two blocks exclusively for 3D
playback L3SS and L4Ss as compared to one block exclusively for 2D playback
(L3+L4)2d, the sizes of the right-view data blocks R3 and R4 can be made
sufficiently smaller than the size of the right-view data block R2 located
immediately before the layer boundary LB shown in FIG. 67A.
[0607] It is thus possible to set each data block in arrangement 6 to be a size at
which seamless playback of video images during a long jump is possible in both 2D
playback mode and L/R mode while keeping the read buffer capacity that is to be
guaranteed in the playback device 102 to the minimum necessary. The same is also
true for depth mode.
[0608] However, since the sizes of the data blocks R4, D4, and L4SS located
immediately before the layer boundary LB in arrangement 6 do not satisfy
expressions 2-5, the buffer margin amounts UL1 and UL2 to be maintained in the
read buffers 4021 and 4022 are not evaluated via expressions 8 and 9, but rather as
follows.
[0609] FIG. 78A is a graph showing changes in the data amount DA1 stored in the
first read buffer 4021 during a read period of data blocks in accordance with the
playback path 7720 in L/R mode shown in FIG. 77B. At the first time TI shown in
FIG. 78A, reading of the last base-view data block L2 in the first 3D extent block
7701 starts. Afterwards, at the second time TJ, reading of the first base-view data
block L5 in the second 3D extent block 7702 starts. Expression 29 yields the
maximum value DR1 of the data amount that can be read from the first read buffer
4021 from the first time TI until the second time TJ.
[0610]

[0611] In this expression, the jump times Tjump-EX, Tjump[2], Tjump[3], and
Tjump-LY
respectively represent the jump times for the second jump Jlr2, the third jump Jlr3,
the fourth jump Jlr4, and the long jump JLY. Furthermore, the sizes Sext2[2] and
Sext2[4] of right-view extents respectively represent the sizes of the right-view data
block R3 located immediately after the block exclusively for 2D playback
(L3+L4)2D and the first right-view data block R5 in the second 3D extent block 7702.
Note that for the purpose of seeking the maximum possible value of the necessary
buffer margin amount, the sizes of the data blocks R4, D4, and L4SS located
immediately before the layer boundary LB are assumed to be zero.
[0612] On the other hand, expression 30 yields the minimum value DI1 of the data
amount that can be stored in the first read buffer 4021 from the first time TI until the
second time TJ.
[0613]

[0614] In this expression, the sizes Sext1[1] and Sext1[2] of base-view extents
respectively represent the sizes of the last base-view data block L2 in the first 3D
extent block 7701 and the block exclusively for 3D playback L3SS located
immediately after the block exclusively for 2D playback (L3+L4)2d-
[0615] To prevent underflow in the first read buffer 4021 during the long jump JLY,
the stored data amount DA1 should be equal to or greater than zero at the second
time TJ. Accordingly, the buffer margin amount UL1 should at least be the
difference between the maximum value DR1 of the data amount that can be read
from the first read buffer 4021 from the first time TI until the second time TJ and the
minimum value DI1 of the data amount that can be stored in the first read buffer
4021 in the same period. That is, the buffer margin amount UL1 is represented in
expression 31.
[0616]
UL1>DR1-DI1

[0617] In this case, since the sizes Sext1[1] and Sext1[2] of the base-view data blocks
L2 and L3SS satisfy expression 4 replacing the depth map data block with the
right-view data block, the second and third terms in expression 31 are both equal to
or less than zero. Therefore, the value of the buffer margin amount UL1 should at
least satisfy expression 32.
[0618]

[0619] FIG. 78B is a graph showing changes in the data amount DA2 stored in the
second read buffer 4022 during a read period of data blocks in accordance with the
playback path 7720 in L/R mode shown in FIG. 77B. At the third time TK shown in
FIG. 78B, reading of the last right-view data block R2 in the first 3D extent block
7701 starts. Afterwards, at the fourth time TL, reading of the first right-view data
block R5 in the second 3D extent block 7702 starts.
[0620] The buffer margin amount UL2 should at least be the difference between the
maximum value of the data amount that can be read from the second read buffer
4022 from the third time TK until the fourth time TL and the minimum value of the
data amount that can be stored in the second read buffer 4022 in the same period.
Accordingly, since the sizes of the right-view data blocks R2 and R3 satisfy
expression 5 replacing the depth map data block with the right-view data block, the
value of the buffer margin amount UL2 should at least satisfy expression 33.
[0621]

[0622] In depth mode as well, for the same reasons the values of the buffer margin
amounts UL1 and UL2 in the read buffers 4021 and 4022 should at least fulfill
expressions 34 and 35.
[06231

[0624] As can be seen by comparing expressions 34 and 35 with expressions 20 and
21, the buffer margin amounts UL1 and UL2 in depth mode are smaller in
arrangement 6 than in arrangement 4. Accordingly, as is clear from expressions
12-14 in modification [N], it is possible to reduce the minimum capacity of the read
buffers 4021 and 4022 in depth mode.
[0625] In arrangement 6, duplicate data of the block exclusively for 2D playback
(L3+L4)2D is divided into two blocks exclusively for 3D playback L3SS and L4SS.
Alternatively, the duplicate data may be provided as a single block exclusively for
3D playback or divided into three or more blocks exclusively for 3D playback.
Furthermore, the block exclusively for 2D playback may be accessible as two or
more extents in the file 2D.
[0626] In arrangement 6, the base-view data blocks in the 3D extent block 7701 may
belong to a different file 2D than the base-view data blocks in the 3D extent block
7702. In this case, in the main path of the 2D playlist file, the CC is set to 5 or 6
between the PIs that specify the playback section in each file 2D. Furthermore, the
two 3D extent blocks 7701 and 7702 belong to different files SS. Accordingly, in the
main path of the 3D playlist file, the CC is set to 5 or 6 between the PIs that specify
the playback section in the file 2D that shares base-view data blocks with the files
SS. On the other hand, in the sub-path of the 3D playlist file, the SP connection
condition (CC) is set to 5 or 6 between the SUB_PIs that specify the playback
section in the file DEP that shares dependent-view data blocks with the files SS.
[0627] [P] Conditional Expressions of Extent Size Referring to Extent ATC Time
[0628] In expressions 2-5, the size of base-view extents and dependent-view extents
is restricted by the size of subsequently located extents. However, from the
perspective of using extents in the authoring process, it is preferable that the
conditions on the size of each extent be expressed in a form that does not depend on
the size of other extents. Accordingly, expressions 2-5 are redefined by conditional
expressions that refer to extent ATC time.
[0629] In the data block groups in the interleaved arrangements shown in FIG. 15
and other figures, three types of contiguous extents Dn, Rn, Ln (n = 0, 1,2, ...) all
have the same extent ATC time Text[n]. The minimum value of these extent ATC
times is set as the minimum extent ATC time minText, and the maximum value as the
maximum extent ATC time maxText: minText < Text[n] < maxText. Let the difference
between the maximum extent ATC time maxText and the minimum extent ATC time
minText be a constant value Tm: maxText = minText + Tm. In this case, the sizes
Sext1[n]5 Sext2[n], and Sext3[n] of the nth extents EXT1[n], EXT2[n], and EXT3[n] are
limited to the ranges in expressions 36, 37, and 38.
[0630]
CEIL(REXT1[n]xminText/8)1) having a minimum extent ATC time minText. As
shown in FIG. 80A, the extent ATC time of the last data block EXT[n] does not
meet the minimum extent ATC time minText. In this case, the extent ATC time of the
last data block EXT[n] is distributed evenly among other data blocks
EXT[0]-EXT[n-l], and each extent ATC time is thus lengthened beyond the
minimum extent ATC time minText. FIG. 80B is a schematic diagram showing
multiplexed stream data that has thus been lengthened. As shown in FIG. 80B, the
extent ATC time of each lengthened data block is longer than the minimum extent
ATC time minText. Furthermore, the extent ATC time of the last data block EXT[n]
shown in FIG. 80A is at most equal to the minimum extent ATC time minText.
Accordingly, the maximum extent ATC time maxText is set to be at least the
maximum value of the lengthened extent ATC time. Expression 44 represents this
condition.
[0651] For example, if the minimum extent ATC time minText is two seconds, then
for multiplexed stream data with an ATC time TDR of 20 or 30 seconds, the
maximum extent ATC time is respectively 2.222 seconds or 2.142 seconds. As the
maximum extent ATC time maxText grows larger, so does the size of the data blocks,
and thus the buffer capacity necessary in the playback device increases. Accordingly,
the relationship between the maximum extent ATC time maxText and the ATC time
TDR of the entire multiplexed stream data is set appropriately in accordance with the
jump capability of the playback device and other factors. In standards, for example,
the ATC time TDR of the entire multiplexed stream data that is to be connected
seamlessly may be restricted to 30 seconds or more, thus limiting the maximum
extent ATC time maxText to 2.15 seconds. The extent ATC time of the last data
block group in the multiplexed stream data can thus always be set to be equal to or
greater than the minimum extent ATC time. As a result, the buffer margin amounts
UL1 and UL2 in the 3D playback device can be further reduced.
[0652] [R] Guaranteeing the Buffer Margin Amount
[0653] The three following methods «I», «II», and «III» are preferable as
methods for guaranteeing the buffer margin amounts UL1 and UL2.
[0654] [R-1 ] Method «I»
[0655] In method «I», the buffer margin amounts UL1 and UL2 are guaranteed in
the following way. First, the condition that "the extent ATC time Text is equal to or
greater than the minimum extent ATC time minText" is placed on the design of each
data block. In this case, as shown in expressions 40-43, the minimum extent ATC
time minText is a value calculated when the mean transfer rates Rext1, Rext2, and Rext3
equal their respective maximum values Rmax1, Rmax2, and Rmax3. The actual mean
transfer rates Rext1, Rext2, and ReXt3, however, are generally lower than their respective
maximum values Rmax1, Rmax2, and Rmax3. Accordingly, the actual sizes of the data
blocks Rext1 x Text, ReXt2 x Text, and ReXt3 x TeXt are generally smaller than the values
assumed in the above conditions, i.e. Rmax1 x Text, Rmax2 x Text, and Rmax x Text.
Therefore, after the start of reading of each data block, reading of the next data block
begins before the extent ATC time Text passes. In other words, the stored data
amounts DA1 and DA2 in the read buffers 4021 and 4022 generally start to increase
again before returning to their value at the start of reading, unlike the case shown in
FIGS. 59A, 59B, 60A, and 60B. The stored data amounts DA1 and DA2 therefore
increase by a predetermined amount each time a pair of a base-view and a
dependent-view data block is read. As a result, by continuously reading a certain
number of data blocks into the read buffers 4021 and 4022, the buffer margin
amounts UL1 and UL2 are guaranteed.
[0656] FIG. 81A is a graph showing the relationship between a 3D extent block
8110 and a playback path 8120 in L/R mode. As shown in FIG. 81 A, the 3D extent
block 8110 is composed of base-view data block groups Lk and dependent-view
data block groups Dk and Rk (k = 0, 1, 2, ...) in an interleaved arrangement. In
accordance with the playback path 8120, each pair of contiguous right-view data
blocks Rk and base-view data blocks Lk is read as one 3D extent, i.e. as a pair of a
dependent-view extent and a base-view extent. The extent Size Sext1[k] of the
base-view extent Lk equals the product of the base-view transfer rate ReXt1[k] and the
extent ATC time Text[k]: Sext1[k] = Rext1[k] x Text[k]. This extent size Sextl[k] is
generally smaller than the product of the maximum value Rmax1 of the base-view
transfer rate and the extent ATC time Text[k]: Sext1[k] < Rmax1 x Text[k]. The same is
true for the extent sizes Sext3[k] and Sext2[k] of the dependent-view extents Dk and
Rk.
[0657] FIG. 81B is a graph showing the change in the data amount DA1 in the first
read buffer 4021 when the 3D extent block 8110 is read in accordance with the
playback path 8120 in L/R mode. The thin line indicates changes when the mean
transfer rates Rext1[k], Rext2[k], and Rext3[k] equal the maximum values Rmax1, Rmax2,
and Rmax3. On the other hand, the thick line indicates changes when the transfer rate
Rext1[0] of the top base-view extent L0 is lower than the maximum value Rmax1. Note
that for convenience of explanation, it is assumed that the dependent-view transfer
rates Rext2[k] and Rext3[k] equal their respective maximum values Rmax2 and RmaX3. In
this case, the sizes ReXt2[k] x Text[k] and Rext3[k] x Text[k] of the dependent-view
extents equal the maximum possible values, Rmax2[k] x Text[k] and Rmax3[k] x Text[k].
[0658] As shown in FIG. 81B, for the thin line, after an extent ATC time Text[0] has
passed from the start of reading of the top base-view extent LO, reading of the next
base-view extent L1 begins. Accordingly, the stored data amount DA1 at this point
is substantially equal to the value DM10 at the start of reading. Conversely, for the
thick line, a time Sext1[0] / Rud-3d is necessary to read the entire top base-view extent
LO from the BD-ROM disc 101 into the first read buffer 4021. This time is shorter
than the time Rmax1[k] x Text[0] / Rud-3D in the thin line by a time ?Tb: ?Tb = Rmax1 x
Text[0] / Rud- 3D - Sextl[0] / Rud-3d = (Rmax1 - Rext1[0]) X Text[0] / Rud-.3D. Accordingly,
the stored data amount DA1 reaches its peak in the thick line earlier than in the thin
line by a time of ATb. On the other hand, the sizes Sext2[1] and Sext3[1] of the
dependent-view extents D1 and R1 are the same for both lines: Rmax2 x Text[1] and
Rmax3 x Text[1]. Accordingly, the time AT from the peak of the stored data amount
DA1 until the start of reading of the next base-view extent L1 is the same for both
lines. As a result, unlike the thin line, reading of the next base-view extent L1 begins
in the thick line at a time that is ATb earlier than after the extent ATC time Text has
passed from the start of reading of the top base-view extent LO. Therefore, the value
DM11 of the stored data amount DA1 at that point increases over the value DM10 at
the start of reading of the top base-view extent LO by an increment DM1 [0]. As is
clear from FIG. 81B, this increase DM1 [0] equals the product of the actual rate of
decrease ReXt1[0] of the stored data amount DA1 and the time ATb: DM1 [0] =
ReXt1[0] x ?Tb = ReXt1[0] x (Rext1[0] - Rmax1) x Text[0] / Rud-3D.
[0659] FIG. 81C is a graph showing the change in the data amount DA2 in the
second read buffer 4022 while the data amount DA1 in the first read buffer 4021
changes as shown in FIG. 81B. The thin line indicates changes when the mean
transfer rates Rext1[k], Rext2[k], and ReXt3[k] equal the maximum values Rmax1, Rmax2,
and Rmax3. On the other hand, the thick line indicates changes when the transfer rate
Rext1[0] of the top base-view extent L0 is lower than the maximum value Rmax1. Note
that for convenience of explanation, it is assumed that the dependent-view transfer
rates Rext2[k] and ReXt3[k] equal their respective maximum values Rmax2 and Rmax3.
[0660] As shown in FIG. 81C, for the thin line, after an extent ATC time Text[0] has
passed from the start of reading of the top right-view extent R0, reading of the next
right-view extent R1 begins. Accordingly, the stored data amount DA2 at this point
is substantially equal to the value DM20 at the start of reading. Conversely, for the
thick line, the entire top base-view extent L0 is read from the BD-ROM disc 101
into the first read buffer 4021 earlier than in the thin line by a time ATb.
Accordingly, reading of the next right-view extent R1 begins in the thick line earlier
than in the thin line by a time ATb, i.e. at a time ATb earlier than the extent ATC
time Text has passed from the start of reading of the top right-view extent R0. As a
result, the value DM21 of the stored data amount DA2 at that point increases over
the value DM20 at the start of reading of the top right-view extent R0 by an
increment DM2[0]. As is clear from FIG. 81C, this increase DM2[0] equals the
product of the actual rate of decrease ReXt2[0] of the stored data amount DA2 and the
time ATb: DM2[0] = ReXt2[0] x ?Tb = Rext2[0] x (Rext1[0] - Rmax1) x Text[0] / Rud-3d-
[0661] In FIGS. 81B and 81C, it is assumed that the dependent-view transfer rates
Rext2[k] and ReXt3[k] equal their respective maximum values Rmax2 and Rmax3. The
actual dependent-view transfer rates Rext2[k] and ReXt3[k], however, are generally
lower than their respective maximum values RmaX2 and Rmax3. In this case, as in FIG.
81B, the stored data amount DA2 in FIG. 81C reaches its peak earlier by a time
Rud.3D. In the graph in FIG. 81B, the time AT from the peak of the stored data
amount DA1 to the start of reading of the next base-view extent L1 is shortened by
the same time ATd. In light of these changes, each time a pair of a base-view extent
Lk and a right-view extent Rk is processed, the stored data amounts DA1 and DA2
in the read buffers increase by increments DM1 [k] and DM2 [k], as shown in
expressions 45 and 46.
[0662]
DM1 [k]=ReXt1[k]x(?Tb+?Td)
[0663] In L/R mode, each time a base-view extent Lk and a right-view extent Rk are
read from a 3D extent EXTSS[k] into the read buffers 4021 and 4022, the stored
data amounts DA1 and DA2 increase by increments DM1 [k] and DM2[k]. Similarly
in depth mode, each time a base-view extent Lk and a depth-map extent Dk are read
into the read buffers 4021 and 4022, the stored data amounts DA1 and DA2 increase
by increments DM3[k] and DM4[k]. These increments DM3[k] and DM4[k] are
shown in expressions 47 and 48.
[0664]
DM3 [k]=

DM4[k]=

[0665] Accordingly, when the total Tsum = Text[0] + Text[1] + Text[2] + ... of the
extent ATC time for the entire 3D extent block 8110 satisfies expression 49, the
buffer margin amounts UL1 and UL2 in the read buffers 4021 and 4022 can be
guaranteed by reading the entire 3D extent block 8110.
[0666]

[0667] The following approximation is used here: throughout the 3D extent block
8110, the base-view transfer rate ReXt1[k] equals the mean value Rext1-av, and the
dependent-view transfer rates Rexe[k] and Rext3[k] respectively equal the mean
Values Rexe-av and Rext3-av
[0668] Method «II»
[0669] In method «II», the buffer margin amounts UL1 and UL2 are guaranteed
as follows. First, the sizes of the data blocks in a sequence of 3D extent blocks
satisfy expressions 50-53, which add a margin time Tmargin, to the right-hand side of
expressions 2-5.
[0670]

[0671] FIGS. 82A and 82B are graphs showing changes in the data amounts DA1
and DA2 stored in the read buffers 4021 and 4022 when a sequence of 3D extent
blocks that satisfy expressions 50-53 is read by the playback device 102 in L/R
mode. As shown in FIGS. 82A and 82B, the effects of adding a margin time Tmargin
to the right-hand side of expressions 2-5 can be interpreted as follows.
[0672] First, the effects of explicitly adding a margin time Tmaigin in the right-hand
side of expressions 50-53 can be described as follows: in expression 51, the value
assumed for the jump time necessary from the start of reading of each right-view
data block until the start of reading of the next right-view data block is longer than
the actual value by the margin time Tmargin. Accordingly, to prevent underflow in the
second read buffer 4022 during this jump time, the size of each right-view data
block includes an additional data amount that is read from the second read buffer
4022 during the margin time Tmargin. As a result, each time a right-view data block is
read, the stored data amount DA2 in the second read buffer 4022 increases by the
product of the right-view transfer rate ReXt2 and the margin time Tmargin. Similarly,
each time a base-view data block is read, the stored data amount DA1 in the first
read buffer 4021 increases by the product of the base-view transfer rate Rext1 and the
margin time Tmargin.
[0673] Next, the effects of implicitly adding a margin time Tmargin in the right-hand
side of expressions 50-53 via the sizes of other data blocks can be described as
follows: the time assumed to be necessary for reading each right-view data block
from the second read buffer 4022 is longer than the actual time by the margin time
Tmargin. On the other hand, during the period in which each right-view data block is
being read from the second read buffer 4022, data is not read into the first read
buffer 4021, and data that is already stored therein is simply read. Accordingly, the
value assumed for the length of the read period is longer than the actual value by the
margin time Tmargin. As a result, each time a right-view data block is read, the stored
data amount DA1 in the first read buffer 4021 increases by the product of the
base-view transfer rate ReXt1 and the margin time Tmargin. Similarly, each time a
base-view data block is read, the stored data amount DA2 in the second read buffer
4022 increases by the product of the right-view transfer rate Rext2 and the margin
time 1 margin-
[0674] Combining the above results, the increase in the stored data amount DA1 in
the first read buffer 4021 caused by reading one base-view data block, i.e. DM1 =
DM11 - DM10, equals two times the product of the base-view transfer rate Rext1 and
the margin time Tmargin: DM1 = 2 x Rext1 x Tmargin. Similarly, the increase in the
stored data amount DA2 in the second read buffer 4022 caused by reading one
dependent-view data block, i.e. DM2 = DM21 - DM20, equals two times the
product of the dependent-view transfer rate Rextk and the margin time Tmargin: DM2 =

[0675] Accordingly, if the total extent ATC time of the entirety of a sequence of 3D
extent blocks, i.e. Tsum = Text[0] + Text[1] + Text[2] + ..., satisfies expression 54,
then the buffer margin amounts UL1 and UL2 can be guaranteed in the read buffers
4021 and 4022 by reading the 3D extent blocks in their entirety.
[0676]

[0677] The following approximation is used in this expression: throughout the 3D
extent blocks, the base-view transfer rate Rext1 equals a mean value Rext1-av, and the
dependent-view transfer rates Rext2 and ReXt3 equal mean values ReXt2-av and ReXt3-av
Furthermore, the extent ATC time Text of each data block equals a mean value Text-av.
[0678] [R-3] Method «III»
[0679] In method «III», the buffer margin amounts UL1 and UL2 are guaranteed
at the start of playback of the AV stream file. For example, at the start of playback,
the playback device in L/R mode does not transfer the top right-view extent
EXT2[0] from the second read buffer 4022 to the system target decoder 4023 until it
has read the entire extent into the second read buffer 4022. Furthermore, in method
«III», transfer from the second read buffer 4022 to the system target decoder
4023 does not begin until a sufficient data amount has been stored from the top
base-view extent EXT1[0] into the first read buffer 4021. As a result, the buffer
margin amounts UL1 and UL2 are respectively stored in the read buffers 4021 and
4022.
[0680] [R-4] Methods «I» and «II» may be combined, and the extent ATC
time Tsum of the 3D extent block in its entirety may be specified by expression 55.
[0681]
[0682] [R-5] When a jump is performed after a 3D extent block and another data
block is read continuously, the jump time for which these data blocks can be
connected seamlessly is represented by the constant Tseamless. At such a point, the
buffer margin amounts UL1 and UL2 are represented by the product of (i) the mean
transfer rates Rext1-av, Rext2-av, and Rext3-av throughout the 3D extent blocks and (ii) the
constant Tscamless: UL1 = Rext1-av x Tscamless, UL2 = ReXt2-av x Tscamless (L/R mode), and
UL2 = ReXt3-av x Tseamless (depth mode). When substituting these values into
expressions 49 and 54, since the depth map transfer rate Rext3-av is generally lower
than the right-view transfer rate Rext2-av, conditions for the total Tsum of the extent
ATC time throughout the 3D extent blocks can be expressed as follows.
[0683]

[0684] [R-6] In methods «I» and «II», as long as a long jump does not occur
during reading of a sequence of 3D extent blocks, the stored data amounts DA1 and
DA2 continue to increase. Accordingly, when the stored data amounts DA1 and
DA2 exceed a threshold, the playback device 102 makes the BD-ROM drive
suspend reading/transfer operations. The read rate Rud-3d thereby decreases, thus
suppressing an increase in the stored data amounts DA1 and DA2. The read buffers
4021 and 4022 can thus avoid overflow.
[0685] [R-7] Buffer Margin Amount in 2D Playback Mode
[0686] In the above embodiment, for example as in arrangement 1 shown in FIG. 68,
a 2D extent of sufficient size is placed immediately before a location where a long
jump is necessary, such as immediately before a layer boundary LB. A sufficient
data amount is thereby stored in the read buffer 3621 immediately before the long
jump, and 2D video images can thus be played back seamlessly. Long jumps,
however, also occur when playback of multiplexed stream data is interrupted for
processing to read from a file, such as a BD-J object file, other than the file for the
multiplexed stream data. As described below, in order to seamless play back 2D
video images despite these long jumps, the playback device 102 in 2D playback
mode may maintain a buffer margin amount in the read buffer 3621 in the same way
as the above-described methods «I» and «II».
[0687] FIG. 83A is a schematic diagram showing the relationships between a 3D
extent block 8310 and a playback path 8320 in 2D playback mode. As shown in FIG.
83A, the 3D extent block 8310 is composed of base-view data blocks Lk and
dependent-view data blocks Dk and Rk (k = 0, 1, 2, ...) in the interleaved
arrangement. In accordance with the playback path 8320, each base-view data block
Lk is read as a single 2D extent.
[0688] FIG. 83B is a graph showing changes in the stored data amount DA in the
read buffer 3621 when the 3D extent block 8310 is read according to the playback
path 8320 in 2D playback mode. The thin line indicates changes when the mean
transfer rate Rext2D[k] equals the maximum value Rmax2D. Conversely, the thick line
indicates changes when the transfer rate ReXt2D[0] of the top 2D extent L0 is lower
than the maximum value Rmax2D.
[0689] As shown in FIG. 83B, for the thin line, after an extent ATC time Text[0] has
passed from the start of reading of the top 2D extent L0, reading of the next 2D
extent L1 begins. Accordingly, the stored data amount DA at this point is
substantially equal to the value DM0 at the start of reading. Conversely, for the thick
line, the time necessary to read the entire top 2D extent L0 from the BD-ROM disc
101 into the read buffer 3621 is shorter than the time in the thin line by a difference
in time AT. Accordingly, the stored data amount DA reaches its peak in the thick
line earlier than in the thin line by a time of AT. As a result, unlike the thin line,
reading of the next 2D extent L1 begins in the thick line at a time that is AT earlier
than after the extent ATC time Text has passed from the start of reading of the top 2D
extent L0. Therefore, the value DM1 of the stored data amount DA1 at that point
increases over the value DM0 at the start of reading of the top 2D extent L0 by an
increment DM[0].
[0690] FIG. 83C is a graph showing changes in the stored data amount DA in the
read buffer 3621 when the entire 3D extent block 8310 shown in FIG. 83A is read.
As shown in FIG. 83C, each time a 2D extent Lk is read, the stored data amount DA
in the read buffer 3621 increases. Accordingly, it is possible to store a sufficient
buffer margin amount in the read buffer 3621 by reading a sufficient number of 2D
extents from the 3D extent block 8310 before a layer switch and before reading of a
BD-J object file or the like. Note that extent ATC time Tsum of the entire 3D extent
block necessary for storing the buffer margin amount is represented, for example, by
the following expression.
[0691]
[0692] [S] Reading of a BD-J Object File
[0693] Processing to read a BD-J object file may interrupt playback of video images
from 3D extent blocks. In this case, the playback device 102 prevents underflow in
the read buffers during interrupt processing as follows.
[0694] FIG. 84A is a schematic diagram showing the case when a BD-J object file is
read during the period in which 3D video images are played back from a 3D extent
block 8401 in accordance with a playback path 8420 in L/R mode. First, the
playback device 102 in L/R mode reads data block groups from the 3D extent block
8401 in accordance with the playback path 8420. As shown in modification [R],
while these data block groups are being read, buffer margin amounts UL1 and UL2
are stored in the read buffers 4201 and 4202. When processing to read a BD-J object
file interrupts, a first long jump JBdj1 from the playback path 8420 to the recording
area 8402 for the BD-J object file occurs. Subsequently, the BD-J object file is read
from the recording area 8402. When reading is finished, a second long jump JBDJ2
from this recording area 8402 to the playback path 8420 occurs. Playback
processing of the 3D extent block 8401 thus restarts from the location at which the
first long jump JBdj1 occurred.
[0695] During the processing to read the BD-J object file shown in FIG. 84A, the
following conditions should be met to prevent underflow in the first read buffer
4021. First, the buffer margin amount UL1 should be equal to or greater than the
data amount read from the first read buffer 4021 from the start of the first long jump
Jbdj1 until the end of the second long jump Jbdj2. Accordingly, the condition the
buffer margin amount UL1 should meet is represented in expression 56 in terms of
the size SJAVa of the BD-J object file that is read, the jump time Tjump of the long
jumps JBDJ1 and JBdj2, and the mean value Rext1-av of the base-view transfer rate for
the entire 3D extent block 8401.
[0696]

[0697] Next, the condition that the time TR for read processing of the BD-J object
file should fulfill is represented in expression 57 in terms of the minimum capacity
RB1 of the first read buffer 4021.
[0698]

[0699] In this expression, the mean transfer rates Rext1-av and Rext2-av for the entire 3D
extent block 8401 equal 192/188 times the mean transfer rates RAVi and RAV2 of TS
packets: Rextk-av = R-AVk x 192 / 188 (k = 1, 2). Furthermore, the maximum values
Rmax1 and Rmax2 of the mean transfer rates Rext1 and Rext2 are respectively equal to the
system rates for the file 2D and file DEP that refer to the 3D extent block 8401, i.e.
192/188 times the recording rates RTS1 and RTS2 of TS packets belonging to each file:
Rmaxk = RTSk x 192 / 188 (k = 1, 2). Expression 57 is calculated the same way as
expression 49.
[0700] Whether or not the playback device 102 in 3D playback mode can guarantee
completion of processing to read the BD-J object file within the time TR may be
expressed as a specific flag. By referring to this flag, an application program can
determine whether or not to read the BD-J object file during playback of 3D video
images. For example, suppose that the system rate RTS1 + RTs2 for the file SS which
refers to the 3D extent block 8401 is 60 Mbps, the sum of the mean transfer rates for
the 3D extent block 8401 RAV1 + RAv2 is 50 Mbps, and the time TR is 20 seconds. In
this case, if the playback device 102 can guarantee reading of the BD-J object file
within 20 seconds or less even when the sum of the mean transfer rates RAv1 + Rav2
is equal to or less than 50 Mbps, it turns the flag on. Otherwise, the playback device
102 turns the flag off.
[0701] FIG. 84B is a schematic diagram showing the case when a BD-J object file is
read while 2D video images are being played back from a 3D extent block 8401 in
accordance with a playback path 8410 in 2D playback mode. First, the playback
device 102 in 2D playback mode reads data block groups from the 3D extent block
8401 in accordance with the playback path 8410. As shown in modification [R],
while these data block groups are being read, the buffer margin amount UL is stored
in the read buffer 3621. When processing to read a BD-J object file interrupts, a first
long jump JBdj1 from the playback path 8410 to the recording area 8402 for the
BD-J object file occurs. Subsequently, the BD-J object file is read from the
recording area 8402. When reading is finished, a second long jump JBDJ2 from this
recording area 8402 to the playback path 8410 occurs. Playback processing of the
3D extent block 8401 thus restarts from the location at which the first long jump
Jbdj1 occurred.
[0702] During the processing to read the BD-J object file shown in FIG. 84B, the
following conditions should be met to prevent underflow in the read buffer 3621.
The condition the buffer margin amount UL should meet is represented in
expression 58 in terms of the size SJAva of the BD-J object file that is read, the jump
time Tjump of the long jumps JBdj1 and Jbdj2, and the mean transfer rate Rext2D-av for
the entire 3D extent block 8401.
[0703]

[0704] In this expression, the read rate Rud-2D of the BD-ROM drive 3601 is, for
example, 54 Mbps. Also, when the jump distance of the long jumps JBdj1 and Jbdj2
is, for example, 1/3 of a stroke, the jump time Tjump equals 1020 ms, which is the
sum of the maximum jump time Tjump_max (1000 ms) and the time necessary for error
correction processing (20 ms).
[0705] Next, the condition the time TR for the reading of the BD-J object file should
meet is represented in expression 59 in terms of the minimum capacity RB of the
read buffer 3621.
[0706]

[0707] In this expression, the mean transfer rates Rext2D-av for the entire 3D extent
block 8401 equals 192/188 times the mean transfer rates RAV of TS packets
belonging to the file 2D: Rext2D-av = R-av x 192 / 188. Furthermore, the maximum
value Rmax2D of the mean transfer rate Rext2d equals the system rate for the file 2D
that refers to the 3D extent block 8401, i.e. 192/188 times the recording rate RTS of
TS packets belonging to the file 2D: Rmax2d = RTs x 192 / 188. Expression 59 is
calculated the same way as expression 57.
[0708] Whether or not the playback device 102 in 2D playback mode can guarantee
completion of processing to read the BD-J object file within the time TR may be
expressed as a specific flag. By referring to this flag, an application program can
determine whether or not to read the BD-J object file during playback of 2D video
images. For example, suppose that the system rate Rxs for the file 2D which refers to
the 3D extent block 8401 is 45 Mbps, the mean transfer rate for the 3D extent block
8401 RAV is 35 Mbps, and the time TR is 20 seconds. In this case, if the playback
device 102 can guarantee reading of the BD-J object file within 20 seconds or less
even when the mean transfer rate RAV is equal to or less than 35 Mbps, it turns the
flag on. Otherwise, the playback device 102 turns the flag off.
[0709] [T] A clip information file may be provided for the file SS in the same way
as for the file 2D and the file DEP. This file is useful for trickplay such as interrupt
playback. In this file, SPNs for an entry map represent serial numbers for source
packets in the entire file SS. Accordingly, the size of each 3D extent needs to be set
to a common multiple, such as 6KB, of the source packet size, 192 bytes, and the
sector size, 2048 bytes.
[0710] FIG. 85A is a schematic diagram representing (k+1) source packets SP #0,
SP #1, SP #2, ..., SP #k to be included in one 3D extent. In FIG. 85A, the length
AT1 of the rectangles representing each source packet SP #0, SP #1, SP #2, ..., SP
#k represents the ATC time of the source packet. This ATC time AT1 equals, in the
playback processing system in 3D playback mode shown in FIG. 58, the amount of
time necessary to transfer the source packet from either of the read buffers 4021 and
4022 to the system target decoder 4023. When a 3D extent consists of source
packets SP #0-SP #k, first the total ATC time of the source packets is set to be equal
to or less than the minimum extent ATC time minText, as shown in FIG. 85A. This
minimum extent ATC time minText equals, for example, the total ATC time for a
6KB source packet group.
[0711] FIG. 85B is a schematic diagram showing the source packets SP #0-SP #k
along an ATC time axis in order of ATS. Each of the positions ATSO-ATSk of the
tops of the rectangles representing the source packets SP #0, SP #1, SP #2, ..., SP #k
represents the value of the ATS for the source packet. During the process of creating
a disc image, free space between the source packets SP #0-SP #k is first detected. In
the example shown in FIG. 85B, there is a space between the time ATS0 + AT1
when SP #0 is completely transferred from the read buffer 4021 or 4022 to the
system target decoder 4023 and the time ATS1 when transfer of SP #1 begins. The
same is true between SP #1 and SP #2. Furthermore, there is a space between the
time ATSk + AT1 when SP #k is completely transferred from the read buffer 4021
or 4022 to the system target decoder 4023 and the time ATS0 + minText, i.e. the time
once the minimum extent ATC time minText has passed after the time ATS0
indicated by the ATS of SP #0.
[0712] FIG. 85C is a schematic diagram showing NULL packets inserted into the
empty regions shown in FIG. 85B. As shown in FIG. 85C, the process of creating a
disc image also includes insertion of NULL packets into the detected free spaces
between the source packets SP#0 - SP#k. As a result, the total of the size of the
source packets SP#0 - SP#k and the NULL packets coincides with 6KB. These
packets are multiplexed into a single 3D extent. The size of each 3D extent is thus
set to 6KB.
[0713] [U] Multi-angle
[0714] FIG. 86A is a schematic diagram showing a playback path for multiplexed
stream data supporting multi-angle. As shown in FIG. 86A, three types of pieces of
stream data L, R, and D respectively for a base-view, right-view, and depth map are
multiplexed in the multiplexed stream data. For example, in L/R mode the base-view
and right-view pieces of stream data L and R are played back in parallel.
Furthermore, pieces of stream data Ak, Bk, and Ck (k = 0, 1,2, ..., n) for different
angles are multiplexed in the section played back during a multi-angle playback
period TANG. The stream data Ak, Bk, and Ck for different angles is divided into
sections for which the playback time equals the angle change interval. Furthermore,
stream data for the base-view, right-view and depth map is multiplexed in each of
the pieces of data Ak, Bk, and Ck. During the multi-angle playback period Tang,
playback can be switched between the pieces of stream data Ak, Bk, and Ck for
different angles in response to user operation or instruction by an application
program.
[0715] FIG. 86B is a schematic diagram showing a data block 8601 recorded on a
BD-ROM disc and a corresponding playback path 8602 in L/R mode. This data
block group 8601 includes the pieces of stream data L, R, D, Ak, Bk, and Ck shown
in FIG. 86A. As shown in FIG. 86B, in addition to the regular pieces of stream data
L, R, and D, the pieces of stream data Ak, Bk, and Ck for different angles are
recorded in an interleaved arrangement. In L/R mode, as shown in the playback path
8602, the right-view and base-view data blocks R and L are read, and reading of the
depth map data blocks D is skipped by jumps. Furthermore, from among the pieces
of stream data Ak, Bk, and Ck for different angles, the data blocks for the selected
angles A0, B1, ..., Cn are read, and reading of other data blocks is skipped by
jumps.
[0716] FIG. 86C is a schematic diagram showing the 3D extent blocks constituting
the pieces of stream data Ak, Bk, and Ck for different angles. As shown in FIG. 86C,
the pieces of stream data Ak, Bk, and Ck for each angle are composed of three types
of data blocks L, R, and D respectively for a base-view, right-view, and depth map.
Furthermore, these data blocks L, R, and D are recorded in an interleaved
arrangement. In L/R mode, as shown by the playback path 8602, from among the
pieces of stream data Ak, Bk, and Ck for different angles, right-view and base-view
data blocks R and L are read for selected angles A0, B1, ..., Cn. Conversely, the
other data blocks are skipped by jumps.
[0717] The 3D extent blocks constituting the pieces of stream data Ak, Bk, and Ck
for each angle may be arranged in the following three ways.
[0718] FIG. 87A is a schematic diagram showing a first 3D extent block 8701
supporting multi-angle and three types of corresponding playback paths 8710, 8720,
and 8730. The playback paths 8710, 8720, and 8730 respectively represent the paths
for 2D playback mode, L/R mode, and depth mode. In the first 3D extent block 8701,
the pieces of stream data Ak, Bk, and Ck for each angle are composed of three data
blocks L, R, and D. In this case, the playback time for one data block equals the
angle change interval. Accordingly, the angle change interval is small. On the other
hand, the buffer margin amount necessary for a jump has to be guaranteed via
reading of one data block. As a result, the mean transfer rate ReXtk (k = 1, 2, 3) of
each data block has to be maintained at a low level.
[0719] FIG. 87B is a schematic diagram showing a second 3D extent block 8702
supporting multi-angle and three types of corresponding playback paths 8711, 8721,
and 8731. In the second 3D extent block 8702, the pieces of stream data Ak, Bk, and
Ck for each angle are composed of seven data blocks Rj, Dj, L, L2D, and Lss (j = 1,
2) in the same interleaved arrangement as in arrangement 6. Furthermore, the sum of
the playback times for two data blocks equals the angle change interval.
Accordingly, the angle change interval is large. Also, for seamless playback in 2D
playback mode, the sum of the sizes of the base-view data block L and the block
exclusively for 2D playback L2D has to be 1.5 times the size of the base-view data
block L shown in FIG. 87A. In 3D playback mode, however, the buffer margin
amount necessary for a jump should be guaranteed by reading two data blocks. For
example, in the playback path 8712 in L/R mode, the pair R1 and L of the first
right-view and base-view data blocks, the next right-view data block R2, and the
block exclusively for 3D playback Lss are read. The same is true for depth mode. As
a result, unlike the arrangement shown in FIG. 8 7A, the mean transfer rate ReXtk (k =
1, 2, 3) of each data block can be maintained at a high value.
[0720] FIG. 87C is a schematic diagram showing a third 3D extent block 8703
supporting multi-angle and three types of corresponding playback paths 8712, 8722,
and 8732. In the third 3D extent block 8703, the pieces of stream data Ak, Bk, and
Ck for each angle are composed of seven data blocks Rj, Dj, Lssj, and L2D, (j = 1, 2).
The arrangement of these data blocks differs from the arrangement shown in FIG.
87B in that the block exclusively for 2D playback L2D is located at the end, and that
the playback path 8712 in 2D playback mode only traverses the block exclusively
for 2D playback L2D. In 3D playback mode, the sum of the playback times for two
data blocks equals the angle change interval. Accordingly, the angle change interval
is large. Also, for seamless playback in 2D playback mode, the size of the block
exclusively for 2D playback L2d has to be two times the size of the base-view data
block L shown in FIG. 8 7A. In 3D playback mode, however, the buffer margin
amount necessary for a jump should be guaranteed by reading two data blocks. For
example, in the playback path 8722 in L/R mode, the pair of the first right-view data
block R1 and the block exclusively for 3D playback Lssl and the pair of the next
right-view data block R2 and the block exclusively for 3D playback Lss2 are read.
The same is true for depth mode. As a result, unlike the arrangement shown in FIG.
87A, the mean transfer rate ReXtk (k = 1, 2, 3) of each data block can be maintained at
a high value. Furthermore, unlike the arrangement shown in FIG. 87B, the block
exclusively for 2D playback L2D is located at the end of each piece of stream data
Ak, Bk, and Ck for each angle. Accordingly, in 3D playback mode, the jump
distances within each angle change interval are short, and thus the mean transfer rate
ReXtk of each data block can be maintained at a higher value than in the arrangement
shown in FIG. 87B.
[0721] Note that in the pieces of stream data Ak, Bk, and Ck for each angle, the
stream data for the base-view, right-view, and depth map may be stored as single
pieces of multiplexed stream data. However, the recording rate has to be limited to
the range of the system rate for which playback is possible in the 2D playback
device. Also, the number of pieces of stream data (TS) to be transferred to the
system target decoder differs between such pieces of multiplexed stream data and
multiplexed stream data for other 3D video images. Accordingly, each piece of
playitem information (PI) may include a flag indicating the number of TS to be
played back. By referring to this flag, the 3D playback device can switch between
these pieces of multiplexed stream data within one playlist file. In the PI that
specifies two TS for playback in 3D playback mode, this flag indicates 2TS. On the
other hand, in the PI that specifies a single TS for playback, such as the above pieces
of multiplexed stream data, the flag indicates ITS. The 3D playback device can
switch the setting of the system target decoder in accordance with the value of the
flag. Furthermore, this flag may be expressed by the value of the connection
condition (CC). For example, a CC of "7" indicates a transition from 2TS to ITS,
whereas a CC of "8" indicates a transition from ITS to 2TS.
[0722] «Embodiment 2»
[0723] The following describes, as the second embodiment of the present invention,
a recording device and a recording method for recording the recording medium of
embodiment 1 of the present invention.
[0724] The recording device described here is called an authoring device. The
authoring device, generally located at a creation studio that creates movie contents to
be distributed, is used by authoring staff. First, in response to operations by the
authoring staff, the recording apparatus converts movie content into a digital stream
that is compression encoded in accordance with an MPEG specification, i.e. into an
AV stream file. Next, the recording device generates a scenario, which is
information defining how each title included in the movie content is to be played
back. Specifically, the scenario includes the above-described dynamic scenario
information and static scenario information. Then, the recording device generates a
volume image or an update kit for a BD-ROM disc from the aforementioned digital
stream and scenario. Lastly, the recording device records the volume image on the
recording medium in accordance with the arrangements of extents explained in
embodiment 1.
[0725] FIG. 88 is a block diagram showing the internal structure of the
above-described recording device. As shown in FIG. 88, the recording device
includes a video encoder 8801, material creation unit 8802, scenario generation unit
8803, BD program creation unit 8804, multiplex processing unit 8805, format
processing unit 8806, and database unit 8807.
[0726] The database unit 8807 is a nonvolatile storage device embedded in the
recording device and is in particular a hard disk drive (HDD). Alternatively, the
database unit 8807 may be an external HDD connected to the recording device, a
nonvolatile semiconductor memory element embedded in the recording device, or an
external nonvolatile semiconductor memory element connected to the recording
device.
[0727] The video encoder 8801 receives video data, such as uncompressed bitmap
data, from the authoring staff, and compresses the received video data in accordance
with a compression/encoding scheme such as MPEG-4 AVC or MPEG-2. This
process converts primary video data into a primary video stream and secondary
video data into a secondary video stream. In particular, 3D video image data is
converted into a base-view video stream and a dependent-view video stream. As
shown in FIG. 7, the video encoder 8801 converts the left-view video stream into a
base-view video stream by performing inter-picture predictive encoding with the
pictures in the left-view video stream. On the other hand, the video encoder 8801
converts the right-view video stream into a dependent-view video stream by
performing inter-picture predictive encoding with not only the pictures in the
right-view video stream but also the pictures in the base-view video stream. Note
that the right-view video stream may be converted into a base-view video stream.
Furthermore, the left-view video stream may be converted into the dependent-view
video stream. The converted video streams 8811 are stored in the database unit
8807.
[0728] During the above-described process of inter-picture predictive encoding, the
video encoder 8801 further detects motion vectors between left video images and
right video images and calculates depth information of each 3D video image based
on the detected motion vectors. The calculated depth information of each 3D video
image is organized into the frame depth information 8810 that is stored in the
database unit 8807.
[0729] FIGS. 89A and 89B are schematic diagrams showing a left-video image
picture and a right-video image picture used in display of one scene in a 3D video
image, and FIG. 64C is a schematic diagram showing depth information calculated
from these pictures by a video encoder 8801.
[0730] The video encoder 8801 first compresses each picture using the redundancy
between the left and right pictures. At that time, the video encoder 8801 compares
an uncompressed left picture and an uncompressed right picture on a
per-macroblock basis (each macroblock containing a matrix of 8 x 8 or 16 x 16
pixels) so as to detect a motion vector for each image in the two pictures.
Specifically, as shown in FIGS. 89A and 89B, a left video picture 8901 and a right
video picture 8902 are each divided into macroblocks 8903, the entirety of which
represents a matrix. Next, the areas occupied by the image data in picture 8901 and
picture 8902 are compared for each macroblock 8903, and a motion vector between
these pieces of image data is detected based on the result of the comparison. For
example, the area occupied by image 8904 showing a "house" in picture 8901 is
substantially the same as that in picture 8902. Accordingly, a motion vector is not
detected from such areas. On the other hand, the area occupied by image 8905
showing a "circle" in picture 8901 is substantially different from the area in picture
8902. Accordingly, a motion vector indicating the displacement between the images
8905 showing the "circles" in the pictures 8901 and 8902 is detected from these
areas.
[0731] The video encoder 8801 next makes use of the detected motion vector not
only when compressing the pictures 8901 and 8902, but also when calculating the
binocular parallax pertaining to a 3D video image constituted from the pieces of
image data 8904 and 8905. Furthermore, in accordance with the binocular parallax
thus obtained, the video encoder 8801 calculates the "depths" of each image, such as
the images 8904 and 8905 of the "house" and "circle". The information indicating
the depth of each image may be organized, for example, into a matrix 8906 the same
size as the matrix of the macroblocks in pictures 8901 and 8902 as shown in FIG.
89C. The frame depth information 8810 shown in FIG. 88 includes this matrix 8906.
In this matrix 8906, blocks 8907 are in one-to-one correspondence with the
macroblocks 8903 in pictures 8901 and 8902. Each block 8907 indicates the depth
of the image shown by the corresponding macroblocks 8903 by using, for example,
a depth of eight bits. In the example shown in FIGS. 89A-C, the depth of the image
8905 of the "circle" is stored in each of the blocks in an area 8908 in the matrix
8906. This area 8908 corresponds to the entire areas in the pictures 8901 and 8902
that represent the image 8905.
[0732] Referring again to FIG. 88, the material creation unit 8802 creates
elementary streams other than video streams, such as an audio stream 8812, PG
stream 8813, and IG stream 8814 and stores the created streams into the database
unit 8807. For example, the material creation unit 8802 receives uncompressed
LPCM audio data from the authoring staff, encodes the uncompressed LPCM audio
data in accordance with a compression/encoding scheme such as AC-3, and converts
the encoded LPCM audio data into the audio stream 8812. The material creation unit
8802 additionally receives a subtitle information file from the authoring staff and
creates the PG stream 8813 in accordance with the subtitle information file. The
subtitle information file defines image data for showing subtitles, display timings of
the subtitles, and visual effects to be added to the subtitles (e.g., fade-in and
fade-out). Furthermore, the material creation unit 8802 receives bitmap data and a
menu file from the authoring staff and creates the IG stream 8814 in accordance
with the bitmap data and the menu file. The bitmap data shows images that are to be
presented on a menu. The menu file defines how each button on the menu is to be
transitioned from one status to another and defines visual effects to be added to each
button.
[0733] The scenario generation unit 8803 creates BD-ROM scenario data 8815 in
response to an instruction that has been issued by the authoring staff and received
via GUI and then stores the created BD-ROM scenario data 8815 in the database
unit 8807. The BD-ROM scenario data 8815 described here is a file group that
defines methods of playing back the elementary streams 8811-8814 stored in the
database unit 8807. Of the file group shown in FIG. 2, the BD-ROM scenario data
8815 includes the index file 211, the movie object file 212, and the playlist files
221-223. The scenario generation unit 8803 further creates a parameter file 8816 and
transfers the created parameter file 8816 to the multiplex processing unit 8805. The
parameter file 8816 defines, from among the elementary streams 8811-8814 stored
in the database unit 8807, stream data to be multiplexed into the main TS and
sub-TS.
[0734] The BD program creation unit 8804 provides the authoring staff with a
programming environment for programming a BD-J object and Java application
programs. The BD program creation unit 8804 receives a request from a user via
GUI and creates each program's source code according to the request. The BD
program creation unit 8804 further creates the BD-J object file 251 from the BD-J
object and compresses the Java application programs in the JAR file 261. The files
251 and 261 are transferred to the format processing unit 8806.
[0735] Here, it is assumed that the BD-J object is programmed in the following way:
the BD-J object causes the program execution units 3634 and 4034 shown in FIGS.
36 and 40 to transfer graphics data for GUI to the system target decoders 3622 and
4023. Furthermore, the BD-J object causes the system target decoders 3622 and
4023 to process graphics data as image plane data. In this case, the BD program
creation unit 8804 may set the offset value corresponding to the image plane data in
the BD-J object by using the frame depth information 8810 stored in the database
unit 8807.
[0736] In accordance with the parameter file 8816, the multiplex processing unit
8805 multiplexes each of the elementary streams 8811-8814 stored in the database
unit 8807 to form a stream file in MPEG-2 TS format. More specifically, as shown
in FIG. 4, each of the elementary streams 8811-8814 is converted into a source
packet sequence, and the source packets included in each sequence are assembled to
construct a single piece of multiplexed stream data. In this manner, the main TS and
sub-TS are created.
[0737] In parallel with the aforementioned processing, the multiplex processing unit
8805 creates the 2D clip information file and dependent-view clip information file
by the following procedure. First, the entry map 2030 shown in FIG. 21 is generated
for each file 2D and file DEP. Next, referring to each entry map, the extent start
point list 2320 shown in FIG. 23 is created. Afterwards, the stream attribute
information shown in FIG. 20 is extracted from each elementary stream to be
multiplexed into the main TS and sub-TS. Furthermore, as shown in FIG. 20, a
combination of an entry map, a piece of 3D meta data, and a piece of stream
attribute information is associated with a piece of clip information.
[0738] The format processing unit 8806 creates a BD-ROM disc image 8820 of the
directory structure shown in FIG. 2 from (i) the BD-ROM scenario data 8815 stored
in the database unit 8807, (ii) a group of program files including, among others, a
BD-J object file created by the BD program creation unit 8804, and (iii) multiplexed
stream data and clip information files generated by the multiplex processing unit
8805. In this directory structure, UDF is used as a file system.
[0739] When creating file entries for each of the files 2D, files DEP, and files SS,
the format processing unit 8806 refers to the entry maps and 3D meta data included
in each of the 2D clip information files and dependent-view clip information files.
The SPN for each entry point and extent start point is thereby used in creating each
allocation descriptor. In particular, allocation descriptors are created so as to
represent the interleaved arrangement shown in FIG. 15. The file SS and file 2D thus
share each base-view data block, and the file SS and file DEP thus share each
dependent-view data block. On the other hand, at locations where a long jump is
necessary, allocation descriptors may be created so as to represent, for example, one
of arrangements 1-6. In particular, some base-view data blocks are referred to by
allocation descriptors in the file 2D as blocks exclusively for 2D playback, and
duplicate data thereof is referred to by allocation descriptors in the file SS as blocks
exclusively for 3D playback. Furthermore, the size of each extent for the base-view
and the dependent-view is set so as to satisfy expressions 1-5, and the value of the
logical address shown by each allocation descriptor is determined accordingly.
[0740] In addition, by using the frame depth information 8810 stored in the database
unit 8807, the format processing unit 8806 creates the offset table shown in FIG.
22A for each secondary video stream 8811, PG stream 8813, and IG stream 8814.
The format processing unit 8806 furthermore stores the offset table in the 3D meta
data for the 2D clip information file. At this point, the positions of image data pieces
within left and right video frames are automatically adjusted so that 3D video
images represented by one stream avoid overlap with 3D video images represented
by other streams in the same visual direction. Furthermore, the offset value for each
video frame is also automatically adjusted so that depths of 3D video images
represented by one stream avoid agreement with depths of 3D video images
represented by other streams.
[0741] Thereafter, the BD-ROM disc image 8820 generated by the format
processing unit 8806 is converted into data suited for pressing of a BD-ROM disc.
This data is then recorded on a BD-ROM disc master. Mass production of the
BD-ROM disc 101 pertaining to embodiment 1 of the present invention is made
possible by pressing the master.
[0742] «Embodiment 3»
[0743] FIG. 90 is a functional block diagram of the integrated circuit 3 according to
embodiment 3 of the present invention. As shown in FIG. 90, the integrated circuit 3
is mounted on a playback device 102 according to embodiment 1. This playback
device 102 includes a medium interface (IF) unit 1, memory unit 2, and output
terminal 10 in addition to the integrated circuit 3.
[0744] The medium IF unit 1 receives or reads data from an external medium ME
and transmits the data to the integrated circuit 3. In particular, this data has the same
structure as data on the BD-ROM disc 101 according to embodiment 1. Types of
medium ME include disc recording media, such as optical discs, hard disks, etc.;
semiconductor memory such as an SD card, USB memory, etc.; broadcast waves
such as CATV or the like; and networks such as the Ethernet™, wireless LAN, and
wireless public networks. In conjunction with the type of medium ME, types of
medium IF unit 1 include a disc drive, card IF, CAN tuner, Si tuner, and network IF.
[0745] The memory unit 2 temporarily stores both the data that is received or read
from the medium ME by the medium IF unit 1 and data that is being processed by
the integrated circuit 3. A synchronous dynamic random access memory (SDRAM),
double-data-rate x synchronous dynamic random access memory (DDRx SDRAM;
x = 1, 2, 3, ...), etc. is used as the memory unit 2. The memory unit 2 is a single
memory element. Alternatively, the memory unit 2 may include a plurality of
memory elements.
[0746] The integrated circuit 3 is a system LSI and performs video and audio
processing on the data transmitted from the medium IF unit 1. As shown in FIG. 90,
the integrated circuit 3 includes a main control unit 6, stream processing unit 5,
signal processing unit 7, memory control unit 9, and AV output unit 8.
[0747] The main control unit 6 includes a processor core and program memory. The
processor core includes a timer function and an interrupt function. The program
memory stores basic software such as the OS. The processor core controls the entire
integrated circuit 3 in accordance with the programs stored, for example, in the
program memory.
[0748] Under the control of the main control unit 6, the stream processing unit 5
receives data from the medium ME transmitted via the medium IF unit 1.
Furthermore, the stream processing unit 5 stores the received data in the memory
unit 2 via a data bus in the integrated circuit 3. Additionally, the stream processing
unit 5 separates visual data and audio data from the received data. As previously
described, the data received from the medium ME includes data configured
according to embodiment 1. In this case, "visual data" includes a primary video
stream, secondary video streams, PG streams, and IG streams. "Audio data"
includes a primary audio stream and secondary audio streams. In particular, the data
configured according to embodiment 1 is separated into a plurality of extents for
main-view data and sub-view data, and the extents are alternately arranged. When
receiving data with this structure, under the control of the main control unit 6, the
stream processing unit 5 extracts the main-view data and stores it in a first area in
the memory unit 2. The stream processing unit 5 also extracts the sub-view stream
and stores it in a second area in the memory unit 2. Main-view data includes the
left-view video stream, and sub-view data includes the right-view video stream. The
reverse may be true. Also, the combination of the main-view and sub-view may be a
combination of 2D video images and corresponding depth maps. The first area and
second area in the memory unit 2 referred to here are a logical division of a single
memory element. Alternatively, each area may be included in physically different
memory elements.
[0749] The visual data and audio data separated by the stream processing unit 5 are
compressed via coding. Types of coding methods for visual data include MPEG-2,
MPEG-4 AVC, MPEG-4 MVC, SMPTE VC-1, etc. In particular, in MPEG-4 AVC,
context-adaptive variable length coding (CAVLC) and context-adaptive binary
arithmetic coding (CABAC) are used as the picture coding method. Types of coding
of audio data include Dolby AC-3, Dolby Digital Plus, MLP, DTS, DTS-HD, linear
PCM, etc. Under the control of the main control unit 6, the signal processing unit 7
decodes the visual data and audio data via a method appropriate for the coding
method used. The signal processing unit 7 corresponds, for example, to each of the
decoders shown in FIG. 41.
[0750] The signal processing unit 7 selects the decoding method for pictures
included in the main-view data (hereinafter, main-view pictures) and pictures
included in the sub-view data (hereinafter, sub-view pictures) in accordance with the
coding method, for example CAVLC/CABAC. Main-view and sub-view pictures
are in one-to-one correspondence. In particular, when decoding one of the sub-view
pictures whose corresponding main-view picture is an I picture or a P picture, the
signal processing unit 7 does not use a B picture as a reference picture. Also, when
the signal processing unit 7 determines the decoding method in accordance with the
coding method for each main-view picture, it refers to the header of the main-view
picture but does not refer to the header of the sub-view picture. Conversely, when
the signal processing unit 7 determines the decoding method in accordance with the
coding method for each sub-view picture, it refers to the header of the sub-view
picture but does not refer to the header of the main-view picture.
[0751] The memory control unit 9 arbitrates access to the memory unit 2 by the
function blocks 5-8 in the integrated circuit 3.
[0752] Under the control of the main control unit 6, the AV output unit 8 processes
the visual data and audio data decoded by the signal processing unit 7 into
appropriate forms and, via separate output terminals 10, outputs the results to the
display device 103 and to speakers in the display device 103. Such processing of
data includes superimposing visual data, converting the format of each piece of data,
mixing audio data, etc.
[0753] FIG. 91 is a functional block diagram showing a typical structure of the
stream processing unit 5. As shown in FIG. 91, the stream processing unit 5 includes
a device stream IF unit 51, a demultiplexer 52, and a switching unit 53.
[0754] The device stream IF unit 51 is an interface that transfers data between the
medium IF unit 1 and the other function blocks 6-9 in the integrated circuit 3. For
example, if the medium ME is an optical disc or a hard disk, the device stream IF
unit 51 includes a serial advanced technology attachment (SATA), advanced
technology attachment packet interface (ATAPI), or parallel advanced technology
attachment (PATA). When the medium ME is a semiconductor memory such as an
SD card, USB memory, etc., the device stream IF unit 51 includes a card IF. When
the medium ME is a broadcast wave such as CATV or the like, the device stream IF
unit 51 includes a tuner IF. When the medium ME is a network such as the
Ethernet™, a wireless LAN, or wireless public network, the device stream IF unit 51
includes a network IF. Depending on the type of medium ME, the device stream IF
unit 51 may achieve part of the functions of the medium IF unit 1. Conversely, when
the medium IF unit 1 is internal to the integrated circuit 3, the device stream IF unit
51 may be omitted.
[0755] From the memory control unit 9, the demultiplexer 52 receives data
transmitted from the medium ME to the memory unit 2 and separates visual data and
audio data from the received data. Each extent included in data structured according
to embodiment 1 consists of source packets for a video stream, audio stream, PG
stream, IG stream, etc., as shown in FIG. 4. In some cases, however, the sub-view
data may not include an audio stream. The demultiplexer 52 reads PIDs from source
packets and, in accordance with the PIDs, separates a source packet group into
visual TS packets VTS and audio TS packets ATS. The separated TS packets Vts and
ATS are transferred to the signal processing unit 7 either directly or after temporary
storage in the memory unit 2. The demultiplexer 52 corresponds, for example, to the
source depacketizers 4111 and 4112 and the PID filters 4113 and 4114 shown in
FIG. 41.
[0756] The switching unit 53 switches the output destination in accordance with the
type of data received by the device stream IF unit 51. For example, when the device
stream IF unit 51 receives the main-view data, the switching unit 53 switches the
storage location of the data to the first area in the memory unit 2. Conversely, when
the device stream IF unit 51 receives the sub-view data, the switching unit 53
switches the storage location of the data to the second area in the memory unit 2.
[0757] The switching unit 53 is, for example, a direct memory access controller
(DMAC). FIG. 92 is a schematic diagram showing the surrounding configuration of
the switching unit 53 in this case. Under the control of the main control unit 6, the
DMAC 53 transmits data received by the device stream IF unit 51 as well as the
address of the location for storage of the data to the memory control unit 9.
Specifically, when the device stream IF unit 51 receives main-view data MD, the
DMAC 53 transmits the main-view data MD along with an address 1 AD1. This
"address 1" AD1 is data indicating the top address AD1 in the first storage area 21
in the memory unit 2. On the other hand, when the device stream IF unit 51 receives
sub-view data SD, the DMAC 53 transmits the sub-view data SD along with an
address 2 AD2. This "address 2" AD2 is data indicating the top address AD2 in the
second storage area 22 in the memory unit 2. The DMAC 53 thus switches the
output destination, in particular the storage location in the memory unit 2, in
accordance with the type of data received by the device stream IF unit 51. The
memory control unit 9 stores the main-view data MD and sub-view data SD
received from the DMAC 53 in the respective areas 21 and 22 of the memory unit 2
shown by the addresses AD1 and AD2 received at the same time.
[0758] The main control unit 6 refers to the extent start points in the clip information
file for the switching unit 53 to switch the storage location. In this case, the clip
information file is received before the main-view data MD and sub-view data SD
and is stored in the memory unit 2. In particular, the main control unit 6 refers to the
file base to recognize that the data received by the device stream IF unit 51 is
main-view data MD. Conversely, the main control unit 6 refers to the file DEP to
recognize that the data received by the device stream IF unit 51 is sub-view data.
Furthermore, the main control unit 6 transmits a control signal CS to the switching
unit 53 in accordance with the results of recognition and causes the switching unit
53 to switch the storage location. Note that the switching unit 53 may be controlled
by a dedicated control circuit separate from the main control unit 6.
[0759] In addition to the function blocks 51, 52, and 53 shown in FIG. 91, the
stream processing unit 5 may be further provided with an encryption engine, a
security control unit, and a controller for direct memory access. The encryption
engine decrypts encrypted data, key data, etc. received by the device stream IF unit
51. The security control unit stores the private key and uses it to control execution of
a device authentication protocol or the like between the medium ME and the
playback device 102.
[0760] In the above example, when data received from the medium ME is stored in
the memory unit 2, the storage location thereof is switched according to whether the
data is main-view data MD or sub-view data SD. Alternatively, regardless of type,
the data received from the medium ME may be temporarily stored in the same area
in the memory unit 2 and separated into main-view data MD and sub-view data SD
when subsequently being transferred to the demultiplexer 52.
[0761] FIG. 931s a functional block diagram showing a typical structure of the AV
output unit 8. As shown in FIG. 93, the AV output unit 8 is provided with an image
superposition unit 81, video output format conversion unit 82, and audio/video
output IF unit 83.
[0762] The image superposition unit 81 superimposes visual data VP, PG, and IG
decoded by the signal processing unit 7. Specifically, the image superposition unit
81 first receives processed right-view or left-view video plane data from the video
output format conversion unit 82 and decoded PG plane data PG and IG plane data
IG from the signal processing unit 7. Next, the image superposition unit 81
superimposes PG plane data PG and IG plane data IG on the video plane data VP in
units of pictures. The image superposition unit 81 corresponds, for example, to the
plane adder 4024 shown in FIGS. 40, 41, and 43.
[0763] The video output format conversion unit 82 receives decoded video plane
data VP from the signal processing unit 7 and superimposed visual data VP/PG/IG
from the image superposition unit 81. Furthermore, the video output format
conversion unit 82 performs various processing on the visual data VP and VP/PG/IG
as necessary. Such processing includes resizing, IP conversion, noise reduction, and
frame rate conversion. Resizing is processing to enlarge or reduce the size of the
visual images. IP conversion is processing to convert the scanning method between
progressive and interlaced. Noise reduction is processing to remove noise from the
visual images. Frame rate conversion is processing to convert the frame rate. The
video output format conversion unit 82 transmits processed video plane data VP to
the image superposition unit 81 and transmits processed visual data VS to the
audio/video output IF unit 83.
[0764] The audio/video output IF unit 83 receives visual data VS from the video
output format conversion unit 82 and receives decoded audio data AS from the
signal processing unit 7. Furthermore, the audio/video output IF unit 83 performs
processing such as coding on the received data VS and AS in conjunction with the
data transmission format. As described below, part of the audio/video output IF unit
83 may be provided externally to the integrated circuit 3.
[0765] FIG. 94 is a schematic diagram showing details regarding data output by the
playback device 102, which includes the AV output unit 8. As shown in FIG. 94, the
audio/video output IF unit 83 includes an analog video output IF unit 83a, digital
video/audio output IF unit 83b, and analog audio output IF unit 83c. The integrated
circuit 3 and playback device 102 are thus compatible with various formats for
transmitting visual data and audio data, as described below.
[0766] The analog video output IF unit 83a receives visual data VS from the video
output format conversion unit 82, converts/encodes this data VS into data VD in
analog video signal format, and outputs the data VD. The analog video output IF
unit 83a includes a composite video encoder, S video signal (Y/C separation)
encoder, component video signal encoder, D/A converter (DAC), etc. compatible
with, for example, one of the following formats: NTSC, PAL, and SEC AM.
[0767] The digital video/audio output IF unit 83b receives decoded audio data AS
from the signal processing unit 7 and receives visual data VS from the video output
format conversion unit 82. Furthermore, the digital video/audio output IF unit 83b
unifies and encrypts the data AS and data VS. Afterwards, the digital video/audio
output IF unit 83b encodes the encrypted data SVA in accordance with data
transmission standards and outputs the result. The digital video/audio output IF unit
83b corresponds, for example, to a high-definition multimedia interface (HDMI) or
the like.
[0768] The analog audio output IF unit 83c receives decoded audio data AS from the
signal processing unit 7, converts this data into analog audio data AD via D/A
conversion, and outputs the audio data AD. The analog audio output IF unit 83c
corresponds, for example, to an audio DAC.
[0769] The transmission format for the visual data and audio data can switch in
accordance with the type of the data reception device/data input terminal provided in
the display device 103/speaker 103A. The transmission format can also be switched
by user selection. Furthermore, the playback device 102 can transmit data for the
same content not only in a single transmission format but also in multiple
transmission formats in parallel.
[0770] The AV output unit 8 may be further provided with a graphics engine in
addition to the function blocks 81, 82, and 83 shown in FIGS. 93 and 94. The
graphics engine performs graphics processing, such as filtering, screen composition,
curve rendering, and 3D presentation processing on the data decoded by the signal
processing unit 7.
[0771] The above-described function blocks shown in FIGS. 90, 91, 93, and 94 are
included in the integrated circuit 3. This is not a requirement, however, and part of
the function blocks may be external to the integrated circuit 3. Also, unlike the
structure shown in FIG. 90, the memory unit 2 may be included in the integrated
circuit 3. Furthermore, the main control unit 6 and signal processing unit 7 need not
be completely separate function blocks. The main control unit 6 may, for example,
perform part of the processing corresponding to the signal processing unit 7.
[0772] The topology of the control bus and data bus that connect the function blocks
in the integrated circuit 3 may be selected in accordance with the order and the type
of the processing by each function block. FIGS. 95A and 95B are schematic
diagrams showing examples of the topology of a control bus and data bus in the
integrated circuit 3. As shown in FIG. 95A, both the control bus 11 and data bus 12
are configured so as to directly connect each of the function blocks 5-9 with all of
the other function blocks. Alternatively, as shown in FIG. 95B, the data bus 13 may
be configured so as to directly connect each of the function blocks 5-8 with only the
memory control unit 9. In this case, each of the function blocks 5-8 transmits data to
the other function blocks via the memory control unit 9 and, additionally, the
memory unit 2.
[0773] Instead of an LSI integrated on a single chip, the integrated circuit 3 may be
a multi-chip module. In this case, since the plurality of chips composing the
integrated circuit 3 are sealed in a single package, the integrated circuit 3 looks like
a single LSI. Alternatively, the integrated circuit 3 may be configured using a field
programmable gate array (FPGA) or a reconfigurable processor. An FPGA is an LSI
that can be programmed after manufacture. A reconfigurable processor is an LSI
whose connections between internal circuit cells and settings for each circuit cell can
be reconfigured.
[0774]
[0775] FIG. 96 is a flowchart of playback processing by a playback device 102 that
uses the integrated circuit 3. This playback processing begins when the medium IF
unit 1 is connected to the medium ME so as to be capable of data transmission, as
for example when an optical disc is inserted into the disc drive. During this
processing, the playback device 102 receives data from the medium ME and decodes
the data. Subsequently, the playback device 102 outputs the decoded data as a video
signal and an audio signal.
[0776] In step S1, the medium IF unit 1 receives or reads data from the medium ME
and transmits the data to the stream processing unit 5. Processing then proceeds to
step S2.
[0777] In step S2, the stream processing unit 5 separates the data received or read in
step S1 into visual data and audio data. Processing then proceeds to step S3.
[0778] In step S3, the signal processing unit 7 decodes each piece of data separated
in step S2 by the stream processing unit 5 using a method appropriate for the coding
method. Processing then proceeds to step S4.
[0779] In step S4, the AV output unit 8 superimposes the pieces of visual data
decoded by the signal processing unit 7 in step S3. Processing then proceeds to step
S5.
[0780] In step S5, the AV output unit 8 outputs the visual data and audio data
processed in steps S2-4. Processing then proceeds to step S6.
[0781] In step S6, the main control unit 6 determines whether the playback device
102 should continue playback processing. When, for example, data that is to be
newly received or read from the medium ME via the medium IF unit 1 remains,
processing is repeated starting at step S1. Conversely, processing ends if the medium
IF unit 1 stops receiving or reading data from the medium ME due to the optical disc
being removed from the disc drive, the user indicating to stop playback, etc.
[0782] FIG. 97 is a flowchart showing details on steps S1-6 shown in FIG. 96. The
steps S101-110 shown in FIG. 97 are performed under the control of the main
control unit 6. Step S101 corresponds mainly to details on step S1, steps S102-S104
correspond mainly to details on step S2, step S105 corresponds mainly to details on
step S3, steps S106-S108 correspond mainly to details on step S4, and steps S109
and S110 correspond mainly to details on step S5.
[0783] In step S101, before reading or receiving from the medium ME, via the
medium IF unit 1, data to be played back, the device stream IF unit 51 reads or
receives data necessary for such playback, such as a playlist and clip information file.
Furthermore, the device stream IF unit 51 stores this data in the memory unit 2 via
the memory control unit 9. Processing then proceeds to step S102.
[0784] In step S102, from the stream attribute information included in the clip
information file, the main control unit 6 identifies the respective coding methods of
the video data and audio data stored in the medium ME. Furthermore, the main
control unit 6 initializes the signal processing unit 7 so that decoding can be
performed in accordance with the identified coding method. Processing then
proceeds to step S103.
[0785] In step S103, the device stream IF unit 51 receives or reads video data and
audio data for playback from the medium ME via the medium IF unit 1. In particular,
this data is received or read in units of extents. Furthermore, the device stream IF
unit 51 stores this data in the memory unit 2 via the switching unit 53 and the
memory control unit 9. In particular, when the main-view data is received or read,
the main control unit 6 switches the storage location of the data to the first area in
the memory unit 2 by controlling the switching unit 53. Conversely, when sub-view
data is received or read, the main control unit 6 switches the storage location of the
data to the second area in the memory unit 2 by controlling the switching unit 53.
Processing then proceeds to step S104.
[0786] In step S104, the data stored in the memory unit 2 is transferred to the
demultiplexer 52 in the stream processing unit 5. The demultiplexer 52 first reads a
PID from each source packet composing the data. Next, in accordance with the PID,
the demultiplexer 52 identifies whether the TS packets included in the source packet
are visual data or audio data. Furthermore, in accordance with the results of
identification, the demultiplexer 52 transmits each TS packet to the corresponding
decoder in the signal processing unit 7. Processing then proceeds to step S105.
[0787] In step S105, each decoder in the signal processing unit 7 decodes
transmitted TS packets using an appropriate method. Processing then proceeds to
step S106.
[0788] In step S106, each picture in the left-view video stream and right-view video
stream that were decoded in the signal processing unit 7 are transmitted to the video
output format conversion unit 82. The video output format conversion unit 82
resizes these pictures to match the resolution of the display device 103. Processing
then proceeds to step S107.
[0789] In step S107, the image superposition unit 81 receives video plane data,
which is composed of pictures resized in step S106, from the video output format
conversion unit 82. On the other hand, the image superposition unit 81 receives
decoded PG plane data and IG plane data from the signal processing unit 7.
Furthermore, the image superposition unit 81 superimposes these pieces of plane
data. Processing then proceeds to step S108.
[0790] In step S108, the video output format conversion unit 82 receives the plane
data superimposed in step S107 from the image superposition unit 81. Furthermore,
the video output format conversion unit 82 performs IP conversion on this plane
data. Processing then proceeds to step S109.
[0791] In step S109, the audio/video output IF unit 83 receives visual data that has
undergone IP conversion in step S108 from the video output format conversion unit
82 and receives decoded audio data from the signal processing unit 7. Furthermore,
the audio/video output IF unit 83 performs coding, D/A conversion, etc. on these
pieces of data in accordance with the data output format in the display device
103/speaker 103 A and with the format for transmitting data to the display device
103/speaker 103A. The visual data and audio data are thus converted into either an
analog output format or a digital output format. Analog output formats of visual data
include, for example, a composite video signal, S video signal, component video
signal, etc. Digital output formats of visual data/audio data include HDMI or the like.
Processing then proceeds to step S110.
[0792] In step S110, the audio/video output IF unit 83 transmits the audio data and
visual data processed in step S109 to the display device 103/speaker 103A.
Processing then proceeds to step S6, a description of which can be found above.
[0793] Each time data is processed in each of the above steps, the results are
temporarily stored in the memory unit 2. The resizing and IP conversion by the
video output format conversion unit 82 in steps S106 and S108 may be omitted as
necessary. Furthermore, in addition to or in lieu of these processes, other processing
such as noise reduction, frame rate conversion, etc. may be performed. The order of
processing may also be changed wherever possible.
[0794] Supplementary Explanation>
[0795] «Principle of 3D Video Image Playback»
[0796] Playback methods of 3D video images are roughly classified into two
categories: methods using a holographic technique, and methods using parallax
video.
[0797] A method using a holographic technique is characterized by allowing a
viewer to perceive objects in video as stereoscopic by giving the viewer's visual
perception substantially the same information as optical information provided to
visual perception by human beings of actual objects. However, although a technical
theory for utilizing these methods for moving video display has been established, it
is extremely difficult to construct, with present technology, a computer that is
capable of real-time processing of the enormous amount of calculation required for
moving video display and a display device having super-high resolution of several
thousand lines per 1 mm. Accordingly, at the present time, the realization of these
methods for commercial use is hardly in sight.
[0798] "Parallax video" refers to a pair of 2D video images shown to each of a
viewer's eyes for the same scene, i.e. the pair of a left-view and a right-view. A
method using a parallax video is characterized by playing back the left-view and
right-view of a single scene so that the viewer sees each view in only one eye,
thereby allowing the user to perceive the scene as stereoscopic.
[0799] FIGS. 90A, 90B, 90C are schematic diagrams illustrating the principle of
playing back 3D video images (stereoscopic video) according to a method using
parallax video. FIG. 90A is a top view of a viewer 9001 looking at a cube 9002
placed directly in front of the viewer's face. FIGS. 90B and 90C are schematic
diagrams showing the outer appearance of the cube 9002 as a 2D video image as
perceived respectively by the left eye 9001L and the right eye 9001R of the viewer
9001. As is clear from comparing FIG. 90B and FIG. 90C, the outer appearances of
the cube 9002 as perceived by the eyes are slightly different. The difference in the
outer appearances, i.e., the binocular parallax allows the viewer 9001 to recognize
the cube 9002 as three-dimensional. Thus, according to a method using parallax
video, left and right 2D video images with different viewpoints are first prepared for
a single scene. For example, for the cube 9002 shown in FIG. 90A, the left view of
the cube 9002 shown in FIG. 90B and the right view shown in FIG. 90C are
prepared. At this point, the position of each viewpoint is determined by the
binocular parallax of the viewer 9001. Next, each video image is played back so as
to be perceived only by the corresponding eye of the viewer 9001. Consequently, the
viewer 9001 recognizes the scene played back on the screen, i.e., the video image of
the cube 9002, as stereoscopic. Unlike methods using a holography technique,
methods using parallax video thus have the advantage of requiring preparation of 2D
video images from merely two viewpoints.
[0800] Several concrete methods for how to use parallax video have been proposed.
From the standpoint of how these methods show left and right 2D video images to
the viewer's eyes, the methods are divided into alternate frame sequencing methods,
methods that use a lenticular lens, and two-color separation methods.
[0801] In alternate frame sequencing, left and right 2D video images are alternately
displayed on a screen for a predetermined time, while the viewer observes the screen
using shutter glasses. Here, each lens in the shutter glasses is, for example, formed
by a liquid crystal panel. The lenses pass or block light in a uniform and alternate
manner in synchronization with switching of the 2D video images on the screen.
That is, each lens functions as a shutter that periodically blocks an eye of the viewer.
More specifically, while a left video image is displayed on the screen, the shutter
glasses make the left-side lens transmit light and the right-hand side lens block light.
Conversely, while a right video image is displayed on the screen, the shutter glasses
make the right-side glass transmit light and the left-side lens block light. As a result,
the viewer sees afterimages of the right and left video images overlaid on each other
and thus perceives a single 3D video image.
[0802] According to the alternate-frame sequencing, as described previously, right
and left video images are alternately displayed in a predetermined cycle. For
example, when 24 video frames are displayed per second for playing back a normal
2D movie, 48 video frames in total for both right and left eyes need to be displayed
for a 3D movie. Accordingly, a display device capable of quickly executing
rewriting of the screen is preferred for this method.
[0803] In a method using a lenticular lens, a right video frame and a left video frame
are respectively divided into reed-shaped small and narrow areas whose longitudinal
sides lie in the vertical direction of the screen. In the screen, the small areas of the
right video frame and the small areas of the left video frame are alternately arranged
in the landscape direction of the screen and displayed at the same time. Here, the
surface of the screen is covered by a lenticular lens. The lenticular lens is a
sheet-shaped lens constituted from parallel-arranged multiple long and thin
hog-backed lenses. Each hog-backed lens lies in the longitudinal direction on the
surface of the screen. When a viewer sees the left and right video frames through the
lenticular lens, only the viewer's left eye perceives light from the display areas of
the left video frame, and only the viewer's right eye perceives light from the display
areas of the right video frame. This is how the viewer sees a 3D video image from
the parallax between the video images respectively perceived by the left and right
eyes. Note that according to this method, another optical component having similar
functions, such as a liquid crystal device, may be used instead of the lenticular lens.
Alternatively, for example, a longitudinal polarization filter may be provided in the
display areas of the left image frame, and a lateral polarization filter may be
provided in the display areas of the right image frame. In this case, the viewer sees
the display through polarization glasses. Here, for the polarization glasses, a
longitudinal polarization filter is provided for the left lens, and a lateral polarization
filter is provided for the right lens. Consequently, the right and left video images are
each perceived only by the corresponding eye, thereby allowing the viewer to
perceive a stereoscopic video image.
[0804] In a method using parallax video, in addition to being constructed from the
start by a combination of left and right video images, the 3D video content can also
be constructed from a combination of 2D video images and a depth map. The 2D
video images represent 3D video images projected on a hypothetical 2D picture
plane, and the depth map represents the depth of each pixel in each portion of the 3D
video image as compared to the 2D picture plane. When the 3D content is
constructed from a combination of 2D video images with a depth map, the 3D
playback device or the display device first constructs left and right video images
from the combination of 2D video images with a depth map and then creates 3D
video images from these left and right video images using one of the
above-described methods.
[0805] FIG. 91 is a schematic diagram showing an example of constructing a
left-view 9103L and a right-view 9103R from a combination of a 2D video image
9101 and a depth map 9102. As shown in FIG. 91, a circular plate 9111 is shown in
the background 9112 of the 2D video image 9101. The depth map 9102 indicates the
depth for each pixel in each portion of the 2D video image 9101. According to the
depth map 9102, in the 2D video image 9101, the display area 9121 of the circular
plate 9111 is closer to the viewer than the screen, and the display area 9122 of the
background 9112 is deeper than the screen. The parallax video generation unit 9100
in the playback device 102 first calculates the binocular parallax for each portion of
the 2D video image 9101 using the depth of each portion indicated by the depth map
9102. Next, the parallax video generation unit 9100 shifts the presentation position
of each portion in the 2D video image 9101 in accordance with the calculated
binocular parallax to construct the left-view 9103L and the right-view 9103R. In the
example shown in FIG. 91, the parallax video generation unit 9100 shifts the
presentation position of the circular plate 9111 in the 2D video image 9101 as
follows: the presentation position of the circular plate 9131L in the left-view 9103L
is shifted to the right by half of its binocular parallax, S1, and the presentation
position of the circular plate 9131R in the right-view 9103R is shifted to the left by
half of its binocular parallax, S1. In this way, the viewer perceives the circular plate
9111 as being closer than the screen. Conversely, the parallax video generation unit
9100 shifts the presentation position of the background 9112 in the 2D video image
9101 as follows: the presentation position of the background 9132L in the left-view
9103L is shifted to the left by half of its binocular parallax, S2, and the presentation
position of the background 9132R in the right-view 9103R is shifted to the right by
half of its binocular parallax, S2. In this way, the viewer perceives the background
9112 as being deeper than the screen.
[0806] A playback system for 3D video images with use of parallax video has
already been established for use in movie theaters, attractions in amusement parks,
and the like. Accordingly, this method is also useful for implementing home theater
systems that can play back 3D video images. In the embodiments of the present
invention, among methods using parallax video, an alternate-frame sequencing
method or a method using polarization glasses is assumed to be used. However,
apart from these methods, the present invention can also be applied to other,
different methods, as long as they use parallax video. This will be obvious to those
skilled in the art from the above explanation of the embodiments.
[0807] «File System on the BD-ROM Disc»
[0808] When UDF is used as the file system for the BD-ROM disc 101, the volume
area 202B shown in FIG. 2 generally includes areas in which a plurality of
directories, a file set descriptor, and a terminating descriptor are respectively
recorded. Each "directory" is a data group composing the directory. A "file set
descriptor" indicates the LBN of the sector in which a file entry for the root
directory is stored. The "terminating descriptor" indicates the end of the recording
area for the file set descriptor.
[0809] Each directory shares a common data structure. In particular, each directory
includes a file entry, directory file, and a subordinate file group.
[0810] The "file entry" includes a descriptor tag, information control block (ICB)
tag, and allocation descriptor. The "descriptor tag" indicates that the type of the data
that includes the descriptor tag is a file entry. For example, when the value of the
descriptor tag is "261", the type of that data is a file entry. The "ICB tag" indicates
attribute information for the file entry itself. The "allocation descriptor" indicates the
LBN of the sector on which the directory file belonging to the same directory is
recorded.
[0811] The "directory file" typically includes several of each of a file identifier
descriptor for a subordinate directory and a file identifier descriptor for a
subordinate file. The "file identifier descriptor for a subordinate directory" is
information for accessing the subordinate directory located directly below that
directory. This file identifier descriptor includes identification information for the
subordinate directory, directory name length, file entry address, and actual directory
name. In particular, the file entry address indicates the LBN of the sector on which
the file entry of the subordinate directory is recorded. The "file identifier descriptor
for a subordinate file" is information for accessing the subordinate file located
directly below that directory. This file identifier descriptor includes identification
information for the subordinate file, file name length, file entry address, and actual
file name. In particular, the file entry address indicates the LBN of the sector on
which the file entry of the subordinate file is recorded. The "file entry of the
subordinate file", as described below, includes address information for the data
constituting the actual subordinate file.
[0812] By tracing the file set descriptors and the file identifier descriptors of
subordinate directories/files in order, the file entry of an arbitrary directory/file
recorded on the volume area 202B can be accessed. Specifically, the file entry of the
root directory is first specified from the file set descriptor, and the directory file for
the root directory is specified from the allocation descriptor in this file entry. Next,
the file identifier descriptor for the directory immediately below the root directory is
detected from the directory file, and the file entry for that directory is specified from
the file entry address therein. Furthermore, the directory file for that directory is
specified from the allocation descriptor in the file entry. Subsequently, from within
the directory file, the file entry for the subordinate directory or subordinate file is
specified from the file entry address in the file identifier descriptor for that
subordinate directory or subordinate file.
[0813] "Subordinate files" include extents and file entries. The "extents" are a
generally multiple in number and are data sequences whose logical addresses, i.e.
LBNs, are consecutive on the disc. The entirety of the extents comprise the actual
subordinate file. The "file entry" includes a descriptor tag, ICB tag, and allocation
descriptors. The "descriptor tag" indicates that the type of the data that includes the
descriptor tag is a file entry. The "ICB tag" indicates attribute information of the
actual file entry. The "allocation descriptors" are provided in a one-to-one
correspondence with each extent and indicate the arrangement of each extent on the
volume area 202B, specifically the size of each extent and the LBN for the top of the
extent. Accordingly, by referring to each allocation descriptor, each extent can be
accessed. Also, the two most significant bits of each allocation descriptor indicate
whether an extent is actually recorded on the sector for the LBN indicated by the
allocation descriptor. More specifically, when the two most significant bits indicate
"0", an extent has been assigned to the sector and has been actually recorded thereat.
When the two most significant bits indicate "1", an extent has been assigned to the
sector but has not been yet recorded thereat.
[0814] Like the above-described file system employing a UDF, when each file
recorded on the volume area 202B is divided into a plurality of extents, the file
system for the volume area 202B also generally stores the information showing the
locations of the extents, as with the above-mentioned allocation descriptors, in the
volume area 202B. By referring to the information, the location of each extent,
particularly the logical address thereof, can be found.
[0815] «Data Distribution via Broadcasting or Communication Circuit»
[0816] The recording medium according to embodiment 1 of the present invention
may be, in addition to an optical disc, a general removable medium available as a
package medium, such as a portable semiconductor memory element including an
SD memory card. Also, embodiment 1 describes an example of an optical disc in
which data has been recorded beforehand, namely, a conventionally available
read-only optical disc such as a BD-ROM or a DVD-ROM. However, the
embodiment of the present invention is not limited to these. For example, when a
terminal device writes a 3D video content that has been distributed via broadcasting
or a network into a conventionally available writable optical disc such as a BD-RE
or a DVD-RAM, arrangement of the extents according to the above-described
embodiment may be used. Here, the terminal device may be incorporated in a
playback device, or may be a device different from the playback device.
[0817] «Playback of Semiconductor Memory Card»
[0818] The following describes a data read unit of a playback device in the case
where a semiconductor memory card is used as the recording medium according to
embodiment 1 of the present invention instead of an optical disc.
[0819] A part of the playback device that reads data from an optical disc is
composed of, for example, an optical disc drive. Conversely, a part of the playback
device that reads data from a semiconductor memory card is composed of an
exclusive interface (I/F). Specifically, a card slot is provided with the playback
device, and the I/F is mounted in the card slot. When the semiconductor memory
card is inserted into the card slot, the semiconductor memory card is electrically
connected with the playback device via the I/F. Furthermore, the data is read from
the semiconductor memory card to the playback device via the I/F.
[0820] «Copyright Protection Technique for Data Stored in BD-ROM Disc»
[0821] Here, the mechanism for protecting copyright of data recorded on a
BD-ROM disc is described, as an assumption for the following supplementary
explanation.
[0822] From a standpoint, for example, of improving copyright protection or
confidentiality of data, there are cases in which a part of the data recorded on the
BD-ROM is encrypted. The encrypted data is, for example, a video stream, an audio
stream, or other stream. In such a case, the encrypted data is decoded in the
following manner.
[0823] The playback device has recorded thereon beforehand a part of data
necessary for generating a "key" to be used for decoding the encrypted data recorded
on the BD-ROM disc, namely, a device key. On the other hand, the BD-ROM disc
has recorded thereon another part of the data necessary for generating the "key",
namely, a media key block (MKB), and encrypted data of the "key", namely, an
encrypted title key. The device key, the MKB, and the encrypted title key are
associated with one another, and each are further associated with a particular ID
written into a BCA 201 recorded on the BD-ROM disc 101 shown in FIG. 2, namely,
a volume ID. When the combination of the device key, the MKB, the encrypted title
key, and the volume ID is not correct, the encrypted data cannot be decoded. In
other words, only when the combination is correct, the above-mentioned "key",
namely the title key, can be generated. Specifically, the encrypted title key is first
decrypted using the device key, the MKB, and the volume ID. Only when the title
key can be obtained as a result of the decryption, the encrypted data can be decoded
using the title key as the above-mentioned "key".
[0824] When a playback device tries to play back the encrypted data recorded on the
BD-ROM disc, the playback device cannot play back the encrypted data unless the
playback device has stored thereon a device key that has been associated beforehand
with the encrypted title key, the MKB, the device, and the volume ID recorded on
the BD-ROM disc. This is because a key necessary for decoding the encrypted data,
namely a title key, can be obtained only by decrypting the encrypted title key based
on the correct combination of the MKB, the device key, and the volume ID.
[0825] In order to protect the copyright of at least one of a video stream and an
audio stream that are to be recorded on a BD-ROM disc, a stream to be protected is
encrypted using the title key, and the encrypted stream is recorded on the BD-ROM
disc. Next, a key is generated based on the combination of the MKB, the device key,
and the volume ID, and the title key is encrypted using the key so as to be converted
to an encrypted title key. Furthermore, the MKB, the volume ID, and the encrypted
title key are recorded on the BD-ROM disc. Only a playback device storing thereon
the device key to be used for generating the above-mentioned key can decode the
encrypted video stream and/or the encrypted audio stream recorded on the BD-ROM
disc using a decoder. In this manner, it is possible to protect the copyright of the data
recorded on the BD-ROM disc.
[0826] The above-described mechanism for protecting the copyright of the data
recorded on the BD-ROM disc is applicable to a recording medium other than the
BD-ROM disc. For example, the mechanism is applicable to a readable and writable
semiconductor memory element and in particular to a portable semiconductor
memory card such as an SD card.
[0827] «Recording Data on a Recording Medium Through Electronic
Distribution»
[0828] The following describes processing to transmit data, such as an AV stream
file for 3D video images (hereinafter, "distribution data"), to the playback device
according to embodiment 1 of the present invention via electronic distribution and to
cause the playback device to record the distribution data on a semiconductor
memory card. Note that the following operations may be performed by a specialized
terminal device for performing the processing instead of the above-mentioned
playback device. Also, the following description is based on the assumption that the
semiconductor memory card that is a recording destination is an SD memory card.
[0829] The playback device includes the above-described card slot. An SD memory
card is inserted into the card slot. The playback device in this state first transmits a
transmission request of distribution data to a distribution server on a network. At this
point, the playback device reads identification information of the SD memory card
from the SD memory card and transmits the read identification information to the
distribution server together with the transmission request. The identification
information of the SD memory card is, for example, an identification number
specific to the SD memory card and, more specifically, is a serial number of the SD
memory card. The identification information is used as the above-described volume
ID.
[0830] The distribution server has stored thereon pieces of distribution data.
Distribution data that needs to be protected by encryption such as a video stream
and/or an audio stream has been encrypted using a predetermined title key. The
encrypted distribution data can be decrypted using the same title key.
[0831] The distribution server stores thereon a device key as a private key common
with the playback device. The distribution server further stores thereon an MKB in
common with the SD memory card. Upon receiving the transmission request of
distribution data and the identification information of the SD memory card from the
playback device, the distribution server first generates a key from the device key, the
MKB, and the identification information and encrypts the title key using the
generated key to generate an encrypted title key.
[0832] Next, the distribution server generates public key information. The public
key information includes, for example, the MKB, the encrypted title key, signature
information, the identification number of the SD memory card, and a device list. The
signature information includes for example a hash value of the public key
information. The device list is a list of devices that need to be invalidated, that is,
devices that have a risk of performing unauthorized playback of encrypted data
included in the distribution data. The device list specifies the device key and the
identification number for the playback device, as well as an identification number or
function (program) for each element in the playback device such as the decoder.
[0833] The distribution server transmits the distribution data and the public key
information to the playback device. The playback device receives the distribution
data and the public key information and records them in the SD memory card via the
exclusive I/F of the card slot.
[0834] Encrypted distribution data recorded on the SD memory card is decrypted
using the public key information in the following manner, for example. First, three
types of checks are performed as authentication of the public key information. These
checks may be performed in any order.
[0835] (1) Does the identification information of the SD memory card included in
the public key information match the identification number stored in the SD memory
card inserted into the card slot?
[0836] (2) Does a hash value calculated based on the public key information match
the hash value included in the signature information?
[0837] (3) Is the playback device excluded from the device list indicated by the
public key information, and specifically, is the device key of the playback device
excluded from the device list?
[0838] If at least any one of the results of the checks (1) to (3) is negative, the
playback device stops decryption processing of the encrypted data. Conversely, if all
of the results of the checks (1) to (3) are affirmative, the playback device authorizes
the public key information and decrypts the encrypted title key included in the
public key information using the device key, the MKB, and the identification
information of the SD memory card, thereby obtaining a title key. The playback
device further decrypts the encrypted data using the title key, thereby obtaining, for
example, a video stream and/or an audio stream.
[0839] The above mechanism has the following advantage. If a playback device,
compositional elements, and a function (program) that have the risk of being used in
an unauthorized manner are already known when data is transmitted via the
electronic distribution, the corresponding pieces of identification information are
listed in the device list and are distributed as part of the public key information. On
the other hand, the playback device that has requested the distribution data
inevitably needs to compare the pieces of identification information included in the
device list with the pieces of identification information of the playback device, its
compositional elements, and the like. As a result, if the playback device, its
compositional elements, and the like are identified in the device list, the playback
device cannot use the public key information for decrypting the encrypted data
included in the distribution data even if the combination of the identification number
of the SD memory card, the MKB, the encrypted title key, and the device key is
correct. In this manner, it is possible to effectively prevent distribution data from
being used in an unauthorized manner.
[0840] The identification information of the semiconductor memory card is
desirably recorded in a recording area having high confidentiality included in a
recording area of the semiconductor memory card. This is because if the
identification information such as the serial number of the SD memory card has
been tampered with in an unauthorized manner, it is possible to realize an illegal
copy of the SD memory card easily. In other words, if the tampering allows
generation of a plurality of semiconductor memory cards having the same
identification information, it is impossible to distinguish between authorized
products and unauthorized copy products by performing the above check (1).
Therefore, it is necessary to record the identification information of the
semiconductor memory card on a recording area with high confidentiality in order to
protect the identification information from being tampered with in an unauthorized
manner.
[0841] The recording area with high confidentiality is structured within the
semiconductor memory card in the following manner, for example. First, as a
recording area electrically disconnected from a recording area for recording normal
data (hereinafter, "first recording area"), another recording area (hereinafter,
"second recording area") is provided. Next, a control circuit exclusively for
accessing the second recording area is provided within the semiconductor memory
card. As a result, access to the second recording area can be performed only via the
control circuit. For example, assume that only encrypted data is recorded on the
second recording area and a circuit for decrypting the encrypted data is incorporated
only within the control circuit. As a result, access to the data recorded on the second
recording area can be performed only by causing the control circuit to store therein
an address of each piece of data recorded in the second recording area. Also, an
address of each piece of data recorded on the second recording area may be stored
only in the control circuit. In this case, only the control circuit can identify an
address of each piece of data recorded on the second recording area.
[0842] In the case where the identification information of the semiconductor
memory card is recorded on the second recording area, then when an application
program operating on the playback device acquires data from the distribution server
via electronic distribution and records the acquired data in the semiconductor
memory card, the following processing is performed. First, the application program
issues an access request to the control circuit via the memory card I/F for accessing
the identification information of the semiconductor memory card recorded on the
second recording area. In response to the access request, the control circuit first
reads the identification information from the second recording area. Then, the
control circuit transmits the identification information to the application program via
the memory card I/F. The application program transmits a transmission request of
the distribution data together with the identification information. The application
program further records, in the first recording area of the semiconductor memory
card via the memory card I/F, the public key information and the distribution data
received from the distribution server in response to the transmission request.
[0843] Note that it is preferable that the above-described application program check
whether the application program itself has been tampered with before issuing the
access request to the control circuit of the semiconductor memory card. The check
may be performed using a digital certificate compliant with the X.509 standard.
Furthermore, it is only necessary to record the distribution data in the first recording
area of the semiconductor memory card, as described above. Access to the
distribution data need not be controlled by the control circuit of the semiconductor
memory card.
[0844] «Application to Real-Time Recording»
[0845] Embodiment 2 of the present invention is based on the assumption that an
AV stream file and a playlist file are recorded on a BD-ROM disc using the
prerecording technique of the authoring system, and the recorded AV stream file and
playlist file are provided to users. Alternatively, it may be possible to record, by
performing real-time recording, the AV stream file and the playlist file on a writable
recording medium such as a BD-RE disc, a BD-R disc, a hard disk, or a
semiconductor memory card (hereinafter, "BD-RE disc or the like") and provide the
user with the recorded AV stream file and playlist file. In such a case, the AV stream
file may be a transport stream that has been obtained as a result of real-time
decoding of an analog input signal performed by a recording device. Alternatively,
the AV stream file may be a transport stream obtained as a result of partialization of
a digitally input transport stream performed by the recording device.
[0846] The recording device performing real-time recording includes a video
encoder, an audio encoder, a multiplexer, and a source packetizer. The video
encoder encodes a video signal to convert it into a video stream. The audio encoder
encodes an audio signal to convert it into an audio stream. The multiplexer
multiplexes the video stream and audio stream to convert them into a digital stream
in the MPEG-2 TS format. The source packetizer converts TS packets in the digital
stream in MPEG-2 TS format into source packets. The recording device stores each
source packet in the AV stream file and writes the AV stream file on the BD-RE
disc or the like.
[0847] In parallel with the processing of writing the AV stream file, the control unit
of the recording device generates a clip information file and a playlist file in the
memory and writes the files on the BD-RE disc or the like. Specifically, when a user
requests performance of recording processing, the control unit first generates a clip
information file in accordance with an AV stream file and writes the file on the
BD-RE disc or the like. In such a case, each time a head of a GOP of a video stream
is detected from a transport stream received from outside, or each time a GOP of a
video stream is generated by the video encoder, the control unit acquires a PTS of an
I picture positioned at the head of the GOP and an SPN of the source packet in
which the head of the GOP is stored. The control unit further stores a pair of the PTS
and the SPN as one entry point in an entry map of the clip information file. At this
time, an "is_angle_change" flag is added to the entry point. The is_angle_change
flag is set to "on" when the head of the GOP is an IDR picture, and "off' when the
head of the GOP is not an IDR picture. In the clip information file, stream attribute
information is further set in accordance with an attribute of a stream to be recorded.
In this manner, after writing the AV stream file and the clip information file into the
BD-RE disc or the like, the control unit generates a playlist file using the entry map
in the clip information file, and writes the file on the BD-RE disc or the like.
[0848] «Managed Copy»
[0849] The playback device according to embodiment 1 of the present invention
may write a digital stream recorded on the BD-ROM disc 101 on another recording
medium via a managed copy. Here, managed copy refers to a technique for
permitting copy of a digital stream, a playlist file, a clip information file, and an
application program from a read-only recording medium such as a BD-ROM disc to
a writable recording medium only in the case where authentication via
communication with the server succeeds. This writable recording medium may be a
writable optical disc, such as a BD-R, BD-RE, DVD-R, DVD-RW, or DVD-RAM, a
hard disk, or a portable semiconductor memory element such as an SD memory card,
Memory Stick™, Compact Flash™, Smart Media™ or Multimedia Card™. A
managed copy allows for limitation of the number of backups of data recorded on a
read-only recording medium and for charging a fee for backups.
[0850] When a managed copy is performed from a BD-ROM disc to a BD-R disc or
a BD-RE disc and the two discs have an equivalent recording capacity, the bit
streams recorded on the original disc may be copied in order as they are.
[0851] If a managed copy is performed between different types of recording media,
a trans code needs to be performed. This "trans code" refers to processing for
adjusting a digital stream recorded on the original disc to the application format of a
recording medium that is the copy destination. For example, the trans code includes
the process of converting an MPEG-2 TS format into an MPEG-2 program stream
format and the process of reducing a bit rate of each of a video stream and an audio
stream and re-encoding the video stream and the audio stream. During the trans code,
an AV stream file, a clip information file, and a playlist file need to be generated in
the above-mentioned real-time recording.
[0852] «Method for Describing Data Structure»
[0853] Among the data structures in embodiment 1 of the present invention, a
repeated structure "there is a plurality of pieces of information having a
predetermined type" is defined by describing an initial value of a control variable
and a cyclic condition in a "for" sentence. Also, a data structure "if a predetermined
condition is satisfied, predetermined information is defined" is defined by describing,
in an "if sentence, the condition and a variable to be set at the time when the
condition is satisfied. In this manner, the data structure described in embodiment 1 is
described using a high level programming language. Accordingly, the data structure
is converted by a computer into a computer readable code via the translation process
performed by a compiler, which includes "syntax analysis", "optimization",
"resource allocation", and "code generation", and the data structure is then recorded
on the recording medium. By being described in a high level programming language,
the data structure is treated as a part other than the method of the class structure in
an object-oriented language, specifically, as an array type member variable of the
class structure, and constitutes a part of the program. In other words, the data
structure is substantially equivalent to a program. Therefore, the data structure needs
to be protected as a computer related invention.
[0854] «Management of Playlist File and Clip Information File by Playback
Program»
[0855] When a playlist file and an AV stream file are recorded on a recording
medium, a playback program is recorded on the recording medium in an executable
format. The playback program makes the computer play back the AV stream file in
accordance with the playlist file. The playback program is loaded from a recording
medium to a memory element of a computer and is then executed by the computer.
The loading process includes compile processing or link processing. By these
processes, the playback program is divided into a plurality of sections in the memory
element. The sections include a text section, a data section, a bss section, and a stack
section. The text section includes a code array of the playback program, an initial
value, and non-rewritable data. The data section includes variables with initial
values and rewritable data. In particular, the data section includes a file, recorded on
the recording device, that can be accessed at any time. The bss section includes
variables having no initial value. The data included in the bss section is referenced
in response to commands indicated by the code in the text section. During the
compile processing or link processing, an area for the bss section is set aside in the
computer's internal RAM. The stack section is a memory area temporarily set aside
as necessary. During each of the processes by the playback program, local variables
are temporarily used. The stack section includes these local variables. When the
program is executed, the variables in the bss section are initially set at zero, and the
necessary memory area is set aside in the stack section.
[0856] As described above, the playlist file and the clip information file are already
converted on the recording device into computer readable code. Accordingly, at the
time of execution of the playback program, these files are each managed as
"non-rewritable data" in the text section or as a "file accessed at any time" in the
data section. In other words, the playlist file and the clip information file are each
included as a compositional element of the playback program at the time of
execution thereof. Therefore, the playlist file and the clip information file fulfill a
greater role in the playback program than mere presentation of data.
[Industrial Applicability]
[0857] The present invention relates to technology for playback of stereoscopic
video images, and as described above, places limits on the type of reference picture
used for compression of dependent-view pictures recorded on a recording medium.
The present invention thus clearly has industrial applicability.
[Reference Signs List]
[0858]
701 base-view video stream
702 right-view video stream
710-719 base-view picture
720-729 dependent-view picture
731, 732 GOP
We claim:
1. A recording medium on which a main-view stream and a sub-view stream are
recorded, the main-view stream being used for monoscopic video playback and the
sub-view stream being used for stereoscopic video playback in combination with the
main-view stream, wherein
the main-view stream includes a plurality of main-view pictures,
the sub-view stream includes a plurality of sub-view pictures,
the main-view pictures and the sub-view pictures are in one-to-one
correspondence, and
when a sub-view picture corresponds to a main-view picture that is one of
an I picture and a P picture, any reference picture used for compression of the
sub-view picture is one of an I picture and a P picture.
2. A recording medium on which a main-view stream and a sub-view stream are
recorded, the main-view stream being used for monoscopic video playback and the
sub-view stream being used for stereoscopic video playback in combination with the
main-view stream, wherein
the sub-view stream is coded with reference to the main-view stream,
the main-view stream includes a plurality of main-view pictures and at least
one main-view picture header,
the sub-view stream includes a plurality of sub-view pictures and at least
one sub-view picture header,
the main-view picture header includes information indicating a coding
method of a main-view picture,
the sub-view picture header includes information indicating a coding
method of a sub-view picture,
each main-view picture refers to the main-view picture header but does not
refer to the sub-view picture header, and
each sub-view picture refers to the sub-view picture header but does not
refer to the main-view picture header.
3. A playback device for playing back video images from a recording medium, the
playback device comprising:
a reading unit operable to read a main-view stream used for monoscopic
video playback and a sub-view stream used for stereoscopic video playback in
combination with the main-view stream; and
a decoding unit operable to extract a compressed picture from stream data
read by the reading unit and decode the compressed picture, wherein
the decoding unit
selects a decoding method of each main-view picture included in the
main-view stream in accordance with a coding method of the main-view picture,
selects a decoding method of each sub-view picture included in the
sub-view stream in accordance with a coding method of the sub-view picture,
sub-view pictures being in one-to-one correspondence with main-view pictures, and
uses one of an I picture and a P picture for any reference picture to
decode any of the sub-view pictures whose corresponding main-view picture is one
of an I picture and a P picture.
4. A playback device for playing back video images from a recording medium, the
playback device comprising:
a reading unit operable to read a main-view stream used for monoscopic
video playback and a sub-view stream used for stereoscopic video playback in
combination with the main-view stream; and
a decoding unit operable to extract a compressed picture from stream data
read by the reading unit and decode the compressed picture, wherein
the decoding unit
refers to a main-view picture header included in the main-view
stream but does not refer to a sub-view picture header included in the sub-view
stream to select individual decoding methods of a plurality of main-view pictures
included in the main-view stream in accordance with individual coding methods of
the main-view pictures, and
refers to the sub-view picture header but does not refer to the
main-view picture header to select individual decoding methods of a plurality of
sub-view pictures included in the sub-view stream in accordance with individual
coding methods of the sub-view pictures.
5. A playback device for playing back video images from a main-view stream used
for monoscopic video playback and a sub-view stream used for stereoscopic video
playback in combination with the main-view stream, the playback device
comprising:
a decoding unit operable to extract a compressed picture from each of the
main-view stream and the sub-view stream, analyze a header included in the
compressed picture, and decode the compressed picture; and
a control unit operable to determine a decoding method of the compressed
picture from the header of the compressed picture analyzed by the decoding unit and
indicate the decoding method to the decoding unit, wherein
during a period when the control unit determines the decoding method of a
compressed picture included in the main-view stream from the header of the
compressed picture, the decoding unit performs one of header analysis and decoding
of a compressed picture included in the sub-view stream, and
during a period when the control unit determines the decoding method of a
compressed picture included in the sub-view stream from the header of the
compressed picture, the decoding unit decodes a compressed picture included in the
main-view stream.
6. A semiconductor integrated circuit for performing video and audio signal
processing on stream data that includes a main-view stream used for monoscopic
video playback and a sub-view stream used for stereoscopic video playback in
combination with the main-view stream, wherein
the main-view stream includes a plurality of main-view pictures,
the sub-view stream includes a plurality of sub-view pictures,
the main-view pictures and the sub-view pictures are in one-to-one
correspondence,
within the stream data, the main-view stream is divided into a plurality of
main-view data groups, the sub-view stream is divided into a plurality of sub-view
data groups, and the main-view data groups and the sub-view data groups are in an
interleaved arrangement,
each of the main-view data groups and the sub-view data groups includes
visual data,
at least one of the main-view data groups and the sub-view data groups
includes audio data,
the semiconductor integrated circuit comprising:
a primary control unit operable to control the semiconductor integrated
circuit;
a stream processing unit operable to receive the stream data, temporarily
store the stream data in a memory internal or external to the semiconductor
integrated circuit, and then demultiplex the stream data into the visual data and the
audio data;
a signal processing unit operable to decode the visual data and the audio
data; and
an AV output unit operable to output the decoded visual data and the
decoded audio data, wherein
the stream processing unit includes a switching unit operable to switch the
storage location of the received stream data between a first area and a second area
that are located in the memory,
the primary control unit controls the switching unit so that the switching
unit stores data belonging to the main-view data groups in the first area and stores
data belonging to the sub-view data groups in the second area, and
the signal processing unit selects individual decoding methods of the
main-view pictures in accordance with individual coding methods of the main-view
pictures, selects individual decoding methods of the sub-view pictures in one-to-one
correspondence with the main-view pictures in accordance with individual coding
methods of the sub-view pictures, and uses one of an I picture and a P picture for
any reference picture to decode any of the sub-view pictures whose corresponding
main-view picture is one of an I picture and a P picture.
7. A semiconductor integrated circuit for performing video and audio signal
processing on stream data that includes a main-view stream used for monoscopic
video playback and a sub-view stream used for stereoscopic video playback in
combination with the main-view stream, wherein
within the stream data, the main-view stream is divided into a plurality of
main-view data groups, the sub-view stream is divided into a plurality of sub-view
data groups, and the main-view data groups and the sub-view data groups are in an
interleaved arrangement,
each of the main-view data groups and the sub-view data groups includes
visual data,
at least one of the main-view data groups and the sub-view data groups
includes audio data,
the main-view stream includes a plurality of main-view pictures and at least
one main-view picture header,
the sub-view stream includes a plurality of sub-view pictures and at least
one sub-view picture header,
the main-view picture header includes information indicating a coding
method of a main-view picture,
the sub-view picture header includes information indicating a coding
method of a sub-view picture,
the semiconductor integrated circuit comprising:
a primary control unit operable to control the semiconductor integrated
circuit;
a stream processing unit operable to receive the stream data, temporarily
store the stream data in a memory internal or external to the semiconductor
integrated circuit, and then demultiplex the stream data into the visual data and the
audio data;
a signal processing unit operable to decode the visual data and the audio
data; and
an AV output unit operable to output the decoded visual data and the
decoded audio data, wherein
the stream processing unit includes a switching unit operable to switch the
storage location of the received stream data between a first area and a second area
that are located in the memory,
the primary control unit controls the switching unit so that the switching
unit stores data belonging to the main-view data groups in the first area and stores
data belonging to the sub-view data groups in the second area,
the signal processing unit refers to the main-view picture header but does
not refer to the sub-view picture header to determine individual coding methods of
the main-view pictures and, in accordance with the individual coding methods,
select individual decoding methods of the main-view pictures, and
the signal processing unit refers to the sub-view picture header but does not
refer to the main-view picture header to determine individual coding methods of the
sub-view pictures and, in accordance with the individual coding methods, select
individual decoding methods of the sub-view pictures.
8. An integrated circuit mounted on a playback device for playing back video images
from a main-view stream used for monoscopic video playback and a sub-view
stream used for stereoscopic video playback in combination with the main-view
stream, the playback device comprising:
a decoding unit operable to extract a compressed picture from each of the
main-view stream and the sub-view stream, analyze a header included in the
compressed picture, and decode the compressed picture; and
a control unit operable to determine a decoding method of the compressed •
picture from the header of the compressed picture analyzed by the decoding unit and
indicate the decoding method to the decoding unit, wherein
during a period when the control unit determines the decoding method of a
compressed picture included in the main-view stream from the header of the
compressed picture, the decoding unit performs one of header analysis and decoding
of a compressed picture included in the sub-view stream, and
during a period when the control unit determines the decoding method of a
compressed picture included in the sub-view stream from the header of the
compressed picture, the decoding unit decodes a compressed picture included in the
main-view stream.

A main-view stream and a sub-view stream are recorded on a recording
medium. The main-view stream is used for monoscopic video playback. The
sub-view stream is used for stereoscopic video playback in combination with the
main-view stream are recorded. The main-view stream includes a plurality of
main-view pictures, and the sub-view stream includes a plurality of sub-view
pictures. The main-view pictures and the sub-view pictures are in one-to-one
correspondence. A B picture is not used as a reference picture for compression of
any of the sub-view pictures whose corresponding main-view picture is one of an I
picture and a P picture.