DESCRIPTION
Title of Invention
RECORDING MEDIUM, PLAYBACK DEVICE, RECORDING DEVICE,
5 PLAYBACK METHOD AND RECORDING METHOD FOR RECORDING
PROGRESSIVE PICTURES AT HIGH FRAME RATE
Technical Field
[0001]
10 The present invention relates to a technical field of video recording.
Background Art
[0002]
In the technical field of video recording, the fi-ame rate and the resolution
15 are widely known as parameters that have a great influence on the quality of video.
The fi-ame rate is a parameter that indicates the number of pictures displayed per
second. The resolution is represented by the number of vertical pixels and the
number of horizontal pixels constituting each of the pictures. For example, the
DVD provides an image quality of SD (Standard Definition) corresponding to a
20 resolution of 720x480, and the Blu-ray disc provides an image quality of HD (High
Definition) corresponding to a resolution of 1920x1080. As such, high-quality
video images can be recorded on the Blu-ray disc.
Citation List
25 Patent Literature
[0003]
Patent Literature 1:
Japanese Patent Application Publication No. 2010-232885
30 Summary of Invention
1
Technical Problem
[0004]
Meanwhile, there are two types of video streams that can be recorded with a
5 conventional application layer format of the recording medium: a video stream
composed of progressive pictures; and a video stream composed of interlace pictures.
For the video stream composed of progressive pictures, 24 Hz (~ 23.976" (=
24000/100001) Hz) is defined as the mandatory frame rate in the standard. The
video stream that is composed of progressive pictures and whose frame rate is 24 Hz
10 is called a "24P" video stream" (accurately speaking, it is 23.976P, but it is called
24P in general). Other known frame rates that can be applied to the video stream
composed of progressive pictures include 24Hz and 25Hz.
[0005]
On the other hand, a representative of the video stream composed of
15 interlace pictures is a video sfream composed of 60 Hz interlace pictures (60i video
stream). The 60i video stream is a video sfream that is composed of interlace
pictures and whose frame rate is 29.97 (30000/100001) Hz. When 29.97 Hz is
converted into the field picture, the number of pictures per second is approximately
60.
20 [0006]
The progressive pictures and the interlace pictures are respectively resfricted
to the above-mentioned frame rates for the following reasons. That is to say, in the
movie industry, movies are generally shot by the progressive method at the above
frame rate, and many movies are saved in the form of films. On the other hand, in
25 the broadcast industry, a large number of videos for TV broadcast are created and
broadcast in 60i. Because it is assumed that the shot videos are used in movies or
broadcast programs, the shooting equipment cannot process a video material whose
frame rate exceeds the above frame rate. However, when a fast-moving image is
shot at a low frame rate, such as 24 Hz, 23.976 (24000/100001) Hz, or 25 Hz, the
30 movement of the image is jumpy and appears unnatural. This provides insufficient
2
video quality. Even in the interlace pictures shot in 60i, the lines in a slanted
direction are deformed and the image deterioration is noticeable.
[0007]
Here, one may consider using the coding of multi-viewpoint images
5 disclosed in Patent Literature 1 to obtain progressive pictures having a high frame
rate. However, when considering a case of recording a video stream, of a movie or
the like, composed of the progressive pictures at a high frame rate onto recording
media and distributing them, a problem of compatibility with player devices that
have already been in market and spread to the homes cannot be avoided. For a
10 general playback device, progressive pictures having a frame rate exceeding the
mandatory frame rate are out of expectation. When progressive pictures having a
frame rate are entered into a playback device which does not support playback at
such a high frame rate, the video decoder may take a heavy load and the video may
not be played back at all, or, if played back, it may display an inappropriate video
15 with some pictures missing. This may embarrass the viewers. Due to the fear
that it may cause such an embarrassment among the viewers, there are many who
consider that a progressive video with such a high frame rate should not be
introduced into the movie production. However, this presents a problem that
realization of the video with a high frame is prevented by such a cautious opinion.
20 [0008]
The following should be noted here. That is to say, in the above
description, the technical problems are explained on the presumption that the frame
rate is 60i or 24P. However, these frame rates were selected just because they are
familiar and convenient for explaining the technical problems. The technical
25 problems of the present application are not limited to the above-described frame
rates. The technical problems that the present application is intenteded to solve
cover a broad range of failures that may occur when a certain resfriction is imposed
on the frame rate, resolution, or encoding method, and are technical barriers that one
having ordinary skill in the art is to face when he/she intends to put the above
30 technology into pratical use in the field of industrial products.
3
[0009]
It is therefore an object of the present invention to minimalize an influence
of a phenomenon that a video stream composed of a plurality of progressive pictures
and having a high frame rate imposes a heavy load onto a video decoder of an
5 existing-type playback device, and prevent the influence from developing into a
product quality problem.
Solution to Problem
[0010]
10 The above object is fulfilled by a recording medium on which are recorded:
an index table; a plurality of digital streams respectively includmg a plurality of
video streams; a plurality of pieces of playlist information respectively defining a
plurality of playback paths of the plurality of video streams; and a plurality of
confrol programs, wherein the plurality of video sfreams include a video sfream
15 composed ofprogressive pictures and a video stream composed of interlace pictures,
and the video stream composed of the progressive pictures has a mandatory rate or
an optional rate, the mandatory rate is a frame rate at which a playback device of any
version can decode and play back the progressive pictures, and the optional rate is a
frame rate at which a playback device of a predetermined version can decode and
20 play back the progressive pictures, each of the plurality of control programs instructs
a playback device to play back one of the plurality of video sfreams in accordance
with one of the plurality of playback paths defmed in the plurality of pieces of
playlist information, the index table indicates one-to-one correspondence between a
plurality of titles and the plurality of confrol programs, the plurality of titles
25 including a first play title and a top menu title, and among the plurality of confrol
programs, control programs corresponding to the first play title and the top menu
title exclude a progressive-optional-rate playback path from a playback target, the
progressive-optional-rate playback path being a playback path for playing back the
progressive pictures in the video sfream at the optional rate.
30
4
(
Advantageous Effects of Invention
[0011]
With the above structure, control programs that are made to correspond to
the core of the playback control exclude, from a playback target, a playback path
5 that specifies a playback of the progressive pictures in the video stream at the
optional frame rate. Thus even when the above recording medium is loaded in a
playback device not supporting playback of the progressive pictures at a frame rate
higher than the mandatory frame rate, or even when the user calls a menu, a video
stream composed of progressive pictures and having a high frame rate is not entered
10 into a video decoder of an old-type playback device. This prevents the screen from
blacking out upon loading of a recording medium, or blacking out upon input of a
menu call.
[0012]
With the above-described structure, when a recording medium is loaded or a
15 menu call is input, a state where "something is displayed on the screen" is ensured.
With such an arrangement, the worst case scenario that the playback device blacks
out can be avoided. This gives a minimum sense of assurance to the manufacturer
of the device. As a result, the structure of the present invention minimalizes an
influence of a phenomenon that a video stream composed of a plurality of
20 progressive pictures and having a high frame rate imposes a heaA^y load onto a video
decoder of an existing-type playback device, and prevents the influence from
developing into a product quality problem.
[0013]
With such ensurance of the playback, the present invention strongly
25 encourages the movie producers and manufacturers, who are both nervous about the
quality problems, to produce movies at high frame rates and develop the application
products. When, encouraged as such, more playback devices of lower prices and
varieties are produced, a more varieties of high-frame-rate contents will be provided.
This will powerfiiUy lead the development of the content-related industry.
30 [0014]
5
When the above recording medium is sold at retail stores or provided as a
rental product in rental shops, users can enjoy watching a movie at home with a
quality not lower than a quality at a movie theater. This will stimulate
development and activity in the movie industry including the retail stores and rental
5 shops. The sensation that is experienced when one watches a movie at a movie
theater can be tasted at home. As such, the recording medium makes a tremendous
contribution to the society also in the aspect of cultural promotion. Furthermore,
its high quality increases the value of the movie as a recorded material when it is
recorded in the archive, and it can be left to posterity as a historical asset. Also,
10 when the recording medium is adopted as a medium of a home video camera, it is
possible to preserve the growth of children and family memorial events in
high-quality videos. This makes it possible for the users to view the preserved
videos later and indulge in fond memories.
15 Brief Description of Drawings
[0015]
FIG. 1 schematically illustrates the contents of the index table and the
control program of Embodiment 1.
FIG. 2 illustrates a data structure in which a plurality of titles are made to
20 correspond to playback paths having the non-60P video attirubute and playback
paths having the 60P video attirubute.
FIG. 3 illustrates the internal structure of the control programs in
Embodiments.
FIG. 4 illustrates an improvement in a data structure of a 60P playlist.
25 FIG. 5 illustrates em improvement in solving the "problem with a data
structure of a SOP playlist.
FIGs. 6A-6D illustrate the structure of the top menu.
FIG. 7 illustrates a home theater system in which the recording medium,
playback device and recording device described in Embodiments 1-7 are used.
30 FIG. 8 illustrates an internal structure of a multi-layered optical disc.
6
FIG. 9 illustrates the application format of the optical disc based on the file
system.
FIG. 10 illustrates the internal structure of the digital stream.
FIGs. 11A and 1 IB illustrate typical three types of video streams.
5 FIGs. 12A and 12B illustrate, in comparison, pictures displayed with the
60P video stream and the 60i video stream.
FIGs. 13A-13D illustrate the transport stream formation process.
FIGs. 14A-14D illustrate the internal structure of the clip information file.
FIGs. 15A-15D illustrate one example of the internal structure of the
10 playlist information.
FIG. 16 illustrates specific settings of the data structures of the index table,
program, and playlist information.
FIG. 17A is a flowchart indicating a processing procedure executed by a
movie object corresponding to the top menu title. FIG. 17B is a flowchart
15 indicating a processing procedure executed by a button object (x).
FIG. 18 illustrates parameter settings for generating a 60P playlist.
FIG. 19 illustrates the structure of a playback device 1001.
FIG. 20 illustrates the internal structure of the system target decoder 103.
FIGs. 21A-21D illustrate a case where a video having been shot by a video
20 camera is recorded on a removable medium and then supplied to a
non-60P-supporting playback device.
FIGs. 22A and FIG. 22B illustrate a case where a removable medium is
loaded into a 60P-supporting playback device.
FIG. 23 illustrates the internal structure of the recording device.
25 FIG. 24 is a flowchart illustrating the entire video recording procedure.
FIG. 25 is a flowchart illustrating the stream recording procedure.
FIG. 26 is a flowchart illustrating a contmuation of the stream recording
procedure.
FIG. 27 illustrates a bit assignment in PSR29.
30 FIGs. 28A and 28B illustrate the recording method of an optical disc.
7
Description of Embodiments
[0016]
The following describes embodiments of the recording device, playback
5 device, recording device, playback method, and recording method encompassed by
the present application, with reference to the attached drawings.
[0017]
(Embodiment 1)
Embodiment 1 is intended to solve the following problem (problem 1) that
10 one having ordinary skill in the art is to face when he/she intends to realize playback
of progressive pictures at the frame rate of 60 Hz, which is a video attribute of the
optional frame rate.
[0018]
Prolem 1: With the progress of the imaging elements and improvement in
15 processing capability of the video processing LSI in recent years, shooting
progressive pictures at a frame rate higher than 24 Hz, 23.976 (24000/100001) Hz or
25 Hz is becoming reality.
[0019]
However, when considering a case of recording a video stream, of a movie
20 or the like, composed of the progressive pictures at a high frame rate onto recording
media and distributing them, it is necessary to address the problem of compatibility
with player devices that have already been in market and spread to the homes.
[0020]
Here, the following considers a case where a recording mediimi is loaded in
25 an existing-type playback device, wherein a video stream composed of progressive
pictures and having a high frame rate is recorded on the recording medium. In that
case, upon the loading, a program executed first from a first play title may instruct to
play back progressive pictures at a high frame rate. Also, a user operation on a
remote control may cause a command "return to top menu title" to be executed,
30 which instructs to play back progressive pictures at a high frame rate.
8
[0021]
When instructed to play back progressive pictures at a high frame rate, a
video decoder embedded in the existing-type playback device takes a heavy
decoding load, and the screen of the display device blacks out. When this happens,
5 the viewer of the existing-type playback device cannot view even a playlist that is
the starting point of the playback, such as the first play title or the top menu title,
appropriately.
[0022]
For example, a 60P video stream is known as a video stream composed of
10 progressive pictures and having a high frame rate that is freated as an optional frame
rate. The 60P video stream is a video stream composed of progressive pictures of
1920x1080 resolution and having a frame rate of 60 Hz. More specifically, the
60P video stream having an optional frame rate displays 60 pictures per second,
which is more than double the 24? video sfream in GOP data scale, thus generating
15 an overscale of GOP. The number of pictures displayced per second being 60
requires the decode timing, which is defined by the decode time stamp (DTS) and
the playback timing, which is defined by the presentation time stamp (PTS), to be
set precisely by accurate time intervals. In addition to this, the entry map points to
the data entries with intervals of double precision.
20 [0023]
When GOPs of such an overscale are entered into an existing type of
playback device that satisfies merely the bare minimum of the specifications of the
Blu-ray Recording, Blu-ray REwritable and Blu-ray Readonly discs, the playback
device, unable to maintain the playback timing for displaying 60 pictures per second,
25 may black out.
[0024]
If the screen blacked out upon loading of a recording medium in a popular,
existing type of playback device, that would be a manufacturer's nightmare, forcing
the manufacturer to field a deluge of complaints.
30 [0025]
9
When a 60p video recorded on the Blu-ray ReadOnly, Blu-ray Recording or
Blu-ray REwritable disc is played back by an existing player device not supporting
the 60P video stream, there is a possibility that the video may be displayed
inappropriately, the viewer's health may be strained, or the player device may take a
5 heavy load and may operate abnormally. Accordingly, it is necessary to provide a
mechanism for preventing an inappropriate playback of video.
[0026]
It is therefore an object of the present embodiment to exclude a possibility
that a non-60P-supporting playback device may take a heavy load by making an
10 attempt to play back a 60P video stream.
[0027]
(Solution 1 to Problem 1) .
In the case where the above problem is solved in the phase of implementing
a recording medium, the recording medium in this phase is a recording medium on
15 which are recorded: an index table; a plurality of digital streams respectively
including a plurality of video streams; a plurality of pieces of playlist information
respectively defining a plurality of playback paths of the plurality of video streams;
and a plurality of control programs, wherein the plurality of video streams include a
video stream composed of progressive pictures and a video stream composed of
20 interlace pictures, and the video stream composed of the progressive pictures has a
mandatory rate or an optional rate, the mandatory rate is a frame rate at which a
playback device of any version can decode and play back the progressive pictures,
and the optional rate is a frame rate at which a playback device of a predetermmed
version can decode and play back the progressive pictures, each of the plurality of
25 control programs instructs a playback device to play back one of the plurality of
video streams in accordance with one of the plurality of playback paths defined in
the plurality of pieces of playlist information, the index table indicates one-to-one
correspondence between a plurality of titles and the plurality of control programs,
the plurality of titles including a first play title and a top menu title, and among the
30 plurality of control programs, confrol programs corresponding to the first play title
10
and the top menu title exclude a progressive-optional-rate playback path from a
playback target, the progressive-optional-rate playback path being a playback path
for playing back the progressive pictures in the video stream at the optional rate.
Solving the problem with the above improvement of the structural elements is an
5 aspect of solution to the problem in this phase.
[0028]
In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of a playback device comprising: a reading unit configured to
10 read an index table from a recording medium; a current number register storing a
current title number which is a title number of a current title; an execution unit
configured to execute a control program which is indicated in the index table as
corresponding to the current title; and a playback unit configured to play back a
video stream selected from a plurality of video streams as instructed by the
15 execution unit, in accordance with one of a plurality of playback paths defined in
playlist information, wherein the plurality of video sfreams include a video stream
composed of progressive pictures and a video stream composed of interlace pictures,
and the video stream composed of the progressive pictures has a mandatory rate or
an optional rate, the mandatory rate is a frame rate at which a playback device of any
20 version can decode and play back the progressive pictures, and the optional rate is a
frame rate at which a playback device of a predetermined version can decode and
play back the progressive pictures, the confrol program instructs the playback device
to play back one of the plurality of video sfreams in accordance with one of a
plurality of playback paths defined in a plurality of pieces of playlist information,
25 the index table indicates one-to-one correspondence between a plurality of titles and
the plurality of confrol programs, the plurality of titles including a first play title and
a top menu title, and among the plurality of confrol programs, confrol programs
corresponding to the first play title and the top menu title exclude a
progressive-optional-rate playback path from a playback target, the
30 progressive-optional-rate playback path being a playback path for playing back the
11
progressive pictures in the video stream at the optional rate.
[0029]
In the case where the above problem is solved in the phase of implementing
a recording device, it is desirable to adapt the problem solving means to the phase by
5 imposing a limitation of a recording device comprising: an encoder configured to
obtain a plurality of digital streams respectively including a plurality of video
streams by performing an encoding process; a generating unit configured to generate
a plurality of pieces of playlist information corresponding to the plurality of digital
streams, a plurality of control programs, and an index table; and a writing imit
10 configured to write the plurality of digital streams, the plurality of pieces of playlist
information, the plurality of control programs, and the index table onto a recording
medium, wherein the plurality of video streams include a video stream composed of
progressive pictures and a video stream composed of interlace pictures, and the
video stream composed of the progressive pictures has a mandatory rate or an
15 optional rate, the mandatory rate is a fi-ame rate at which a playback device of any
version can decode and play back the progressive pictures, and the optional rate is a
fi-ame rate at which a playback device of a predetermined version can decode Eind
play back the progressive pictures, each of a plurality of control programs instructs
the playback device to play back one of the plurality of video streams in accordance
20 with one of the plurality of playback paths defined in the plurality of pieces of
playlist information, the index table indicates one-to-one correspondence between a
plurality of titles and the plurality of control programs, the plurality of titles
including a first play title and a top menu title, and among the plurality of control
programs, control programs corresponding to the first play title and the top menu
25 title exclude a progressive-optional-rate playback path fi-om a playback target, the
progressive-optional-rate playback path being a playback path for playing back the
progressive pictures in the video stream at the optional rate.
[0030]
In the case where the above problem is solved in the phase of implementing
30 a playback method, it is desirable to adapt the problem solving means to the phase
12
by imposing a limitation of a playback method comprising: reading an index table
from a recording medium; executing a control program which is indicated in the
index table as corresponding to a current title whose title number is stored in a
current number register as a current title number; and playing back a video stream
5 selected from a plurality of video streams as instructed by the execution unit, in
accordance with one of a plurality of playback paths defined in playlist information,
wherein the plurality of video streams include a video stream composed of
progressive pictures and a video stream composed of interlace pictures, and the
video stream composed of the progressive pictures has a mandatory rate or an
10 optional rate, the mandatory rate is a frame rate at which a playback device of any
version can decode and play back the progressive pictures, and the optional rate is a
frame rate at which a playback device of a predetermined version can decode and
play back the progressive pictures, the control program instructs the playback device
to play back one of the plurality of video streams in accordance with one of a
15 plurality of playback paths defined in a plurality of pieces of playlist information,
the index table indicates one-to-one correspondence between a plurality of titles and
the plurality of control programs, the plurality of titles including a first play title and
a top menu title, and among the plurality of confrol programs, control programs
corresponding to the first play title and the top menu title exclude a
20 progressive-optional-rate playback path from a playback target, the
progressive-optional-rate playback path being a playback path for playing back the
progressive pictures in the video stream at the optional rate.
[0031]
In the case where the above problem is solved in the phase of implementing
25 a recording method, the recording method in this phase is a recording method
comprising: encoding to obtain a plurality of digital streams; generating a plurality
of pieces of playlist information corresponding to the plurality of digital sfreams, a
plurality of control programs, and an index table; and writing the plurality of digital
sfreams, the plurality of pieces of playlist information, the plurality of control
30 programs, and the index table onto a recording medium, wherein the plurality of
13
video streams include a video stream composed of progressive pictures and a video
stream composed of interlace pictures, and the video stream composed of the
progressive pictures has a mandatory rate or an optional rate, the mandatory rate is a
frame rate at which a playback device of any version can decode and play back the
5 progressive pictures, and the optional rate is a frame rate at which a playback device
of a predetermined version can decode and play back the progressive pictures, each
of a plurality of control programs instructs the playback device to play back one of
the plurality of video streams in accordance with one of the plurality of playback
paths defined in the plurality of pieces of playlist information, the index table
10 indicates one-to-one correspondence between a plurality of titles and the plurality of
control programs, the plurality of titles including a first play title and a top menu
title, and among the plurality of control programs, control programs corresponding
to the first play title and the top menu title exclude a progressive-optional-rate
playback path from a playback target, the progressive-optional-rate playback path
15 being a playback path for playing back the progressive pictures in the video stream
at the optional rate.
[0032]
Here, the "mandatory frame rate (mandatory rate)" is a frame rate at which a
playback device of any version can perform decoding and playback. For example,
20 the version upgrade of the Blu-ray Readonly disc application standard has been
performed repeatedly since the issuance of the first version (the logical format of the
Blu-ray Readonly disc includes R0M2 and ROMS, the oldest one being ROM2
established in early May, 2006), and decoding and playback of the 24P video stream
and 601 video stream are possible in all of the versions. Accordingly, 24 Hz of the
25 24P video stream and 60 Hz of the 60i video stream are mandatory rates in the
Blu-ray ReadOnly disc application standard.
[0033]
The "optional frame rate (optional rate)" is a frame rate at which a limited
versions of playback devices can perform decoding and playback. Currently,
30 decoding and playback of a 60P video stream at 60 Hz are not available with current
14
Blu-ray Readonly discs, but will be allowed when the standard is revised in the near
future. Accordingly, 60 Hz of the 60P video stream corresponds to the optional
rate in the Blu-ray Readonly disc application standard.
[0034]
5 FIG. 1 illustrates a data structure improved for solving the above-described
problem. FIG. 1 schematically illustrates the contents of the index table and the
control program of Embodiment 1.
[0035]
The following describes the problem solving process performed by the
10 above problem solving means. A specific example is used here for the explanation.
That is to say, it is supposed that a content of sports involving fast-moving subjects
and a content involving slow-moving subjects are encoded and recorded on the same
recording medium. Specific examples of such images are shown in FIG. 1. Note
that, in the following, the examples provided in FIG. 1 are used in the explanation of
15 the contents of the recording medium, unless it is explicitly stated otherwise.
[0036]
FIG. 1 indicates that one digital stream including a video stream composed
of progressive pictures of an optional fi-ame rate (60P video stream) and three digital
streams including non-60P video streams are present, and that the four digital
20 streams are referred to by four pieces of playlist information
"00001.MPLS"-"00004.MPLS". Note that the non-60P video stream is a 24P
video stream or a 601 video stream, wherein the 24P video stream is composed of
progressive pictures and its fi-ame rate is 24 Hz, and the 60i video stream is
composed of interlace pictures and its fi-ame rate is 60 Hz.
25 [0037]
In the present Description, the 601 video stream is used as one example of
the non-60P video stream. However, it is considered that, m the actuality, the 24P
video stream is generally used as the non-60P video stream. This is because the
24P video stream is the same as the 60P video stream except for the fi"ame rate, and
30 is similar to the 60P video stream in image quality when the shooting subjects move
15
slowly.
[0038]
It is also presumed that there are three control programs
"00001.PRG"-"00003.PRG" and the control programs are made to correspond to
5 the title numbers of the first play title, top menu title, and title 1 in the index table,
respectively. Among the four pieces of playlist information, the first, second and
fourth pieces of playlist information (00001 .MPLS, 00002.MPLS, 00004.MPLS) are
playback paths having the non-60P video attribute, and the third piece of playlist
information (00003.MPLS) is a playback path having the 60P video attribute.
10 [0039]
The left-hand side of FIG. 1 illustrates the index table that includes indexes
corresponding to the first play title, top menu title, and title 1. The arrows "loadl",
"load2" and "load3" schematically illustrate loading of control programs based on
the corresponding indexes in the index table. The arrows "instl", "inst2", "inst3"
15 and "inst4" schematically illustrate playlist playback instructions issued by the
control programs. The frames "winl" and "win2" indi indicates a closeup of the
internal structure of the stream information.
[0040]
The following describes the index table. The index table defines the
20 correspondence between a plurality of title numbers that can be stored in the title
number register provided in the playback device and program files that define the
operation modes. It should be noted here that the title numbers that can be stored
in the title number register include "0^,"99E'", and an undefined value
"OxFFFF". A title number "0" is a title number ofthe top menu title.
25 [0041]
The top menu is a menu of the highest rank in the hierarchy of menus in the
recording medium, and is a menu at the core of the structure where titles transition
among each other. The top menu title is a title that can be called by a menu call
operation performed by the user. The title number by the undefined value
30 "OxFFFF" is a title number ofthe first play title. The first play title is a title that
16
displays a warning to the viewer, a logo of the content provider and so on
immediately after the recording medium is loaded. The index table includes entries
(title indexes) in one-to-one correspondence with title numbers. A program file is
described in each title index, each program file defining an operation mode. With
5 this structure, the index table defines in detail how each title operates in a
corresponding operation mode.
[0042]
A description of the digital stream is given here. The digital stream is
variable-length data composed of a series of fixed-size packets. The digital stream
10 does not need to be resident in memory, but is partially read fi-om the recording
medium to the memory as necessary. The AV stream is a digital stream that
contains at least video and audio.
[0043]
The following explains the playlist information. The playlist information
15 includes one or more pieces of playitem information, and defines a playback path
composed of one or more playback sections. The playback section is a closed
section defined by a pair of "In_Time" and "Out_Time" of the playitem information
based on the playback time axis of the stream file that is paired with clip information
specified by the playitem information. The playback path defmed by the playlist
20 information is an access route of the digital stream defined by interpreting the
arrangement order of a plurality of pieces of playitem information in one piece of
playlist information as the order of the playback path.
[0044]
As illustrated in FIG. 1, the program OOOOl.PRG corresponding to the first
25 play title includes a command "PlayPL(OOOOl)" that instructs a playback of
progressive pictures or interlace pictures at the fi"ame rate of 24 Hz. The program
00002.PRG corresponding to the top menu title includes a command
"PlayPL(00002)" that instructs a playback of progressive pictures or interlace
pictures at the fi-ame rate of 24 Hz. In this way, the control programs (OOOOl.PRG
30 and 00002.PRG) referred to by the first play title and the top menu title refer to
17
playback paths (00001.MPLS and 00002.MPLS) that do not include the 60P video
attribute. With the above structure of the index table, when a viev^^er plays back the
recording medium with a player device that does not support 60P, the viewer can
play back at least (i) the playback path (00001.MPLS) referred to by the first play
5 title and (ii) the playback path (00002.MPLS) referred to by the top menut title.
[0045]
According to the present embodiment, a video shot in 60P to be played back
as the first play title or the top menu title is converted into a 24P video stream or a
60i video stream, wherein the 24P video stream is composed of progressive pictures
10 and its frame rate is 24 Hz, and the 60i video stream is composed of interlace
pictures and its frame rate is 60 Hz, and then digital streams including such video
streams are recorded on a recording medium. Thus when the recording medium is
loaded in a non-60P-supporting playback device, playback of the first play title and
the top menu title is ensured. With such minimum ensurance of the playback, the
15 present embodiment strongly encourages the movie producers and manufacturers,
who are both nervous about the quality problems, to produce movies at high frame
rates and develop the application products. When, encouraged as such, more
playback devices of lower prices and varieties are produced, a more varieties of
high-frame-rate contents will be provided. This will powerfully lead the
20 development of the content-related industry.
[0046]
(Embodiment 2)
The present embodiment is intended to supplement Embodiment 1
technically in solving the problem 1. More specifically, the present embodiment is
25 intended to solve the following problem 2.
[0047]
Problem 2: when a non-60P-supporting playback device attempts to play
back a title which is other than the first play title or the top menu title and includes a
60P video stream, the title is not played back at all, or played back with frame
30 dropping, namely, it is not possible to play back progressive pictures at the frame
18
rate of 24 Hz or interlace pictures by using non-6-P playback paths to come up with
qualities that viewers hope for.
[0048]
It is therefore an object of the present embodiment to satisfy the
5 expectations held by the viewers for the 60P video stream.
[0049]
(Solution 1 to Problem 2)
The above-described problem solving means is improved as follows to
solve the problem 2.
10 [0050]
In the case where the above problem is solved in the phase of implementing
a recording medium, in the recording medium in this phase, among the plurality of
control programs, one or more control programs, which respectively correspond to
one or more general titles that include neither the first play title nor the top menu
15 title, instruct the playback device to play back the video stream composed of the
progressive pictures at the optional rate, on a condition that the playback device has
a capability to process the video stream composed of the progressive pictures at the
optional rate. Solving the problem with the above improvement of the structural
elements is an aspect of solution to the problem in this phase.
20 [0051]
In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solvmg means to the phase by
imposing a limitation of the playback device in which, among the plurality of
control programs, one or more control programs, which respectively correspond to
25 one or more general titles that include neither the first play title nor the top menu
title, instruct the playback device to play back the video stream composed of the
progressive pictures at the optional rate, on a condition that the playback device has
a capability to process the video stream composed of the progressive pictures at the
optional rate, the playback device further comprising: a player setting register
30 indicating one or more capabilities of the playback device; and a title management
19
unit configured to, when the player setting register indicates that the playback device
has a capability to process the progressive-optional-rate playback path, set a title
number of a title corresponding to the progressive-optional-rate playback path into
the title number register in accordance with the control program executed by the
5 execution unit.
[0052]
In the case where the above problem is solved in the phase of implementing
a recording device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the recording device in which the index table is generated to
10 make one or more general titles that include neither the first play title nor the top
menu title among the plurality of titles to correspond to one or more control
programs which instruct the playback device to play back the video stream
composed of the progressive pictures at the optional rate, on a condition that the
playback device has a capability to process the video stream composed of the
15 progressive pictures at the optional rate, and then the index table is written on the
recording medium.
In the above structure, the following lower concepts of the control program
are provided. As one lower concept, the control program is an object program in a
command-interpreter-based operation mode, and includes one or more navigation
20 commands. In that case, a playback in accordance with a playback path defined in
the playlist information may be performed by a playlist playback command that is
one of the navigation commands.
[0053]
As another lower concept, the control program is a bytecode application
25 (BD-J application) in a bypecode-interpreter-based operation mode, and includes
one or more bypecodes. In that case, a playback in accordance with a playback
path defined in the playlist information may be performed by a call of an application
interface instructing to generate a player instance, and in generating the player
instance, a playlist information file may be specified by a locator.
30 [0054]
20
With this lower concept of the control program, it is possible to use a
bytecode that corresponds to the conditional branch command or the if statement
structure written in an object-oriented programming language to set a condition for
playing back a playlist having the 60P video attribute. This makes it possible to
5 play back a 60P playlist only when the playback device has the capability to play
back the 60P playlist. In this way, the above two aspects of control programs can
be adopted. In the following description, however, the former, namely the object
program (called a "movie object") in a command-interpreter- based operation mode
is adopted for the sake of simple explanation.
10 [0055]
The following describes the problem solving process performed by the
problem solving means having the above improvement with reference to FIG. 1.
[0056]
The "60P-Capability" illustrated in the upper-right portion of FIG. 1
15 represents the content of the system parameter (player variable) in the playback
device. The 60P capability includes: a decode capability of being capable to
decode a plurality of access units constituting the GOPs included in a 60P video
stream at regular intervals of 1/60 seconds; and a presentation capability of being
capable to write 1920x1080 pixels constituting a decompressed picture obtained by
20 the decoding into a video plane at regular intervals of 1/60 seconds for use in an
overlay with graphics. In terms of the speed performance, the decode capability
and the presentation capability are required to be able to decode each picture at
regular intervals of 1/60 seconds and to write each decompressed picture obtained
by the decoding into the video plane at regular intervals of 1/60 seconds,
25 respectively.
[0057]
Conversely, with regard to the decode capability of the video decoder, if the
video decoder cannot decode or play back pictures at regular intervals of 1/60
seconds, it can be said that the video decoder does not have the 60P capability.
30 [0058]
21
Users or content producers cannot judge whether a playback device has a
capability to play back 60P video streams. Only the manufacturer of the playback
device can determine whether to provide the playback device with the capability to
play back 60P video streams. When the hardware specification of the playback
5 device satisfies the above-stated conditions of memory size, decode capability and
presentation capability, the manufacturer of the playback device sets the 60P
capability of the playback device as "provided". Conversely, when the hardware
specification of the playback device does not satisfy the conditions of memory size,
decode capability and presentation capability, the manufacturer of the playback
10 device sets the 60P capability of the playback device as "not provided". A
dotted-line arrow refl in FIG. 1 schematically indicates that the program
00003 .PRG refers to the player variable (system parameter) in the player device.
[0059]
The following explains how the control program judges whether or not a
15 playlist is a 60P playlist. The content producer knows well which playlists are 60?
playlists. Accordingly, with regard to a playlist created by the content producer, a
control program created by the content producer can judge accurately whether or not
the playlist is a 60P playlist. On the other hand, with regard to a playlist created by
another content producer, the control program checks on whether or not the playlist
20 is a 60P playlist by checking on whether or not the version number of the playlist
information indicates a predetermined version or later (the reason for this is
described below). Also, since a bytecode application (BD-J application) is merely
a program, it can judge whether or not a playlist to be played back is a 60P playlist
by referring to details of the clip information file in the playlist.
25 [0060]
That is to say, the bytecode application can judge whether or not a playlist
to be played back is a 60P playlist only by referring to the stream attribute in the clip
information referred to by clip_information_file_name of the playitem information
included in the playlist information. It is possible to judge whether or not a playlist
30 to be played back is a 60P playlist by judging whether or not the stream attribute
22
information of the clip information referred to by clip_information_file_name of any
playitem information.
[0061]
In FIG. 1, control program 00003 .PRG corresponding to title 1 includes: (1)
5 judging whether or not the playback device has the 60P capability; (2) instructing to
play back progressive pictures at the frame rate of 60 Hz when the 60P capability is
provided — PlayPL(00003); and (3) instructing to play back progressive pictures at
the frame rate of 24 Hz or play back interlace pictures according to a non-60P
playback path when the 60? capability is not provided — PlayPL(00004). As
10 indicated by the above (1), (2) and (3), control program 00003.PRG corresponding
to title 1 instructs to play back progressive pictures at 60 Hz based on a
predetermined condition. This suggests that playing back progressive pictures at
60 Hz is made limited. Another variation of the solution to the problem is
illustrated in FIG. 2.
15 [0062]
FIG. 2 illustrates a data structure in which a plurality of titles are made to
correspond to playback paths having the non-60P video attirubute and playback
paths having the 60P video attirubute. The structure of FIG. 2 differs from the
structure of FIG. 1 in that there are four titles and four control programs, and titles 1
20 and 2 are made to correspond to 00003 .PRG and 00004.PRG, respectively. The
arrows loadS and load6 in FIG. 2 indicate that 00003 .PRG and 00004.PRG are
loaded when titles 1 and 2 are selected, respectively. The structure of FIG. 2 also
differs from the structure of FIG. 1 in that each of the programs instructs to play
back pictures accordmg to a playback path having the 60P attribute or a playback
25 path having the non-60P attribute. The reference sign refZ indicates referencing of
information that indicates whether or not the playback device has the 60P capability.
The confrol program 00003 .PRG judges whether or not the playback device can play
back a 60P video stream by referring to the "60P capability" included in the player
variable (system parameter), and when the playback device can play back, starts
30 playing back the progressive pictures at 60 Hz.
23
[0063]
As described above, according to the present embodiment, a playback of
progressive pictures at the frame rate of 60 Hz, which is an optional frame rate, is
performed on a condition that the playback device has the 60P capability, thereby
5 preliminarily preventing a 60P video stream from being entered into a
non-60P-supporting playback device at the stage of title selection.
[0064]
(Embodiment 3)
The present embodiment discloses a solution to a new problem caused by
10 the title direct search. The title direct search is a function to start playing back a
title of a specified title number, without via the top menu title or the like when a
viewer directly inputs the title number into the player device by operating a remote
control or the like. Regardless of whether the top menu title is present, the control
transitions to the title having the input title number, and an attempt is made to play
15 back progressive pictures at 60 Hz. Accordingly, even if the player device used by
the viewer does not support 60P, the player device starts playing back the
progressive pictures at 60 Hz. When this happens, the above-described problem 2
occurs.
[0065]
20 It is therefore an object of the present embodiment to plug up a loophole
where a quality may be impaired when the user uses the title direct search.
[0066]
This loophole can be closed by preventing, at the stage of title selection, the
title direct search from being entered to play back a title that involves a playback of
25 a 60P video stream.
[0067]
In the case where the above problem is solved m the phase of unplementing
a recording medium, it is desirable to adapt the problem solving means to the phase
by imposing a limitation of the recording medium in which the plurality of control
30 programs include a plurality of mask flags, the plurality of mask flags each
24
indicating whether or not a search operation for searching a corresponding title is
prohibited, and among the plurality of mask flags, one or more mask flags
corresponding to one or more titles that instruct to play back the progressive pictures
at the optional rate are set to indicate that search operations for searching the one or
5 more titles are prohibited.
[0068]
In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the playback device further comprising a receiving unit
10 configured to receive a title search request from a user, wherein the plurality of
control programs include a plurality of mask flags, the plurality of mask flags each
indicating whether or not a search operation for searching a corresponding title is
prohibited, among the plurality of mask flags, one or more mask flags corresponding
to one or more titles that instruct to play back the progressive pictures at the optional
15 rate are set to indicate that search operations for searching the one or more titles are
prohibited, and the execution unit refers to a mask flag of a control program
corresponding to a title number for which a title search request has been issued, and
when the mask flag indicates that a search operation for searching the title is not
prohibited, executes a processing procedure defined in the control program
20 corresponding to the title number for which the title search request has been issued,
and when the mask flag indicates that the search operation for searching the title is
prohibited, does not execute the processing procedure defined in the control program
corresponding to the title number for which the title search request has been issued.
[0069]
25 In the case where the above problem is solved in the phase of implementing
a recording device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the recording device in which, when writing the
progressive-optional-rate playback path, which includes a first-attribute playback
section defined for a video stream that satisfies a condition of being composed of
30 progressive pictures and having the optional rate, onto the recording medium, when
25
the progressive-optional-rate playback path includes another playback section, a
video stream defined by the another playback section is regarded to satisfy the
condition, and information indicating presence of the first-attribute playback section
is set in a playlist that includes one or more first-attribute playback sections. The
5 above improvement for solving the problem is illustrated in the data structure of FIG.
3. FIG. 3 illustrates the internal structure of the control programs in Embodiment
3.
[0070]
The structure of FIG. 3 differs from the structure of FIG. 2 in that (1) in
10 control program 00003.PRG for instructing to play back a 60P video stream, a flag
for masking a title search (title_search_mask) is set ON to prohibit the title direct
search, and (2) in control program 00004 .PRG for instructing to play back
progressive pictures at the frame rate of 24 Hz or interlace pictures, the flag for
masking a title search (title_search_mask) is set OFF to permit the title direct search.
15 [0071]
When a plurality of titles registered in the index table include a title that
includes a 60P video stream, the title_search_mask flag of the control program
corresponding to the title is set ON to prohibit the title search of the title, and the
title_search_mask flag of the control program corresponding to a title that does not
20 include a 60P video stream is set OFF to validate the title search of the title. With
this structure, the title transition by the title direct search is. restricted, thereby
making it possible to prevent progressive pictures from starting to be played back at
the frame rate of 60Hz, confrary to the intention, in a player device that does not
support the 60P playback.
25 [0072]
Here, if it is difficult for the viewers to understand why some titles are
prohibited and others are permited to be searched by the title direct search, the title
direct search may be prohibited with regard to all the titles so that a selection of a
title can be received only from the top menu. By recording the data, which has a
30 data structure based on an appropriate combination of the above solutions to the
26
problems 1 and 2, onto a disc, it is possible to prevent a player device not supporting
60P from playing back progressive pictures at the frame rate of 60 Hz.
[0073]
(Embodiment 4)
5 The present embodiment explains an improvement to be added to the
playlist to solve the problems 1 and 2.
[0074]
The playback devices available in the market include player devices
supporting the 60P playback and player devices not supporting the 60P playback.
10 [0075]
It is desirable that a playlist does not include both a playitem specifying a
60P video stream and a playitem specifying a video stream that can be played back
in an existing player device and is other than a 60? video stream. The reason for
this is as follows. From the standpoint of viewers, it is desirable that even a player
15 device not supporting 60? can playback a playitem specifying a video stream that is
other than a 60? video stream and can be played back in an existmg player device.
However, many manufacturers, who in general advocate the supremacy of the
qualify, demand a complete prohibition of supply of the 60? video streams to the
video decoder. For this reason, when a playlist including a playitem specifying a
20 60? video stream also includes a playitem specifying a non-60? video stream that
can be played back in a player device not supporting 60?, the playlist should be
excluded from the target of playback.
[0076]
It is therefore an object of the present, embodiment to exclude a possibility
25 that a 60? video stream is entered into a non-60?-supporting playback device,
imposing a heavy load onto the playback device, in circumstances where a playback
path of a 60i/24P video stream may also have a 60? video stream.
[0077]
In the case where the above problem is solved in the phase of implementing
30 a recording medium, the recording medium in this phase is the recordmg medium in
27
which the progressive-optionai-rate playback path includes a first-attribute playback
section defined for a video stream that satisfies a condition of being composed of
progressive pictures and having the optional rate, and in a case where the
progressive-optional-rate playback path includes another playback section, a video
5 stream defined by the another playback section is regarded to satisfy the condition,
and information indicating presence of the first-attribute playback section is set in a
playlist that includes one or more first-attribute playback sections. Solving the
problem with the above improvement of the structural elements is an aspect of
solution to the problem in this phase.
10 [0078]
In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the playback device in which the progressive-optional-rate
playback path includes a first-attribute playback section defined for a video stream
15 that satisfies a condition of being composed of progressive pictures and having the
optional rate, and in a case where the progressive-optional-rate playback path
includes another playback section, a video stream defined by the another playback
section is regarded to satisfy the condition, and information indicating presence of
the first-attribute playback section is set in a playlist that includes one or more
20 first-attribute playback sections, the playback device further comprising: a playitem
number register storing a current playitem number identifying a current piece of
playitem information among a plurality of pieces of playitem information which
respectively define a plurality of playback sections in one playback path; a
demultiplexing unit configured to demultiplex, from a digital stream, one or more
25 elementary streams that are indicated in a stream selection table of the current piece
of playitem information as being permitted to be played back; and a video decoder
configured to decode a video stream included in the one or more elementary
streams.
[0079]
30 In the case where the above problem is solved in the phase of implementing
28
a recording device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the recording device in which, when writing the
progressive-optional-rate playback path, which includes a first-attribute playback
section defined for a video stream that satisfies a condition of being composed of
5 progressive pictures and having the optional rate, onto the recording medium, when
the progressive-optional-rate playback path includes another playback section, a
video stream defined by the another playback section is regarded to satisfy the
condition, and information indicating presence of the first-attribute playback section
is set in a playlist that includes one or more first-attribute playback sections.
10 [0080]
In the present embodiment, a concept "60P video attribute" is introduced in
the playback path defined by the playlist information. The following describes a
detailed structure of the 60P playlist having the 60P video attribute. With regard to
a playlist that includes a 60? video stream, the version number of the playlist is set
15 to a different value firom that of a playlist that includes only existing, mandatory
video streams. When the playlist version numbers are set in this way, it indicates
that a target playlist includes a video stream that is composed progressive pictures
and has an optional fi-ame rate.
[0081]
20 Here, the "playlist version number" is a version nimiber that is set in an
MPLS file which is a playlist information file. By setting the playlist version
number to a special value or a value that is greater than an existing one, it is possible
to indicate that the corresponding playlist information file is a 60P playlist. This is
because, when the playlist version number is set in this way, the subject of the
25 player device recognizes that the playlist as the target of playback includes some
update.
[0082]
As described above, a playlist is a playback path, and is formed by
arranging one or more playback sections defined for one or more digital streams.
30 By indicating whether or not each playback path has a video attribute of "60P", the
29
stream video attributes of the clip information files corresponding to respective
digital streams are united in a virtual manner, and attributes of playitem information
defining the playback sections are united in a virtual manner. Here, "united"
means that, when a plurality of digital streams constituting a playlist include a
5 digital stream that is composed of progressive pictures and has an optional fi-ame
rate, the video attributes of the whole digital streams constituting the playlist are
regarded as "60P".
[0083]
Conversely, when each of a plurality of digital streams constituting a
10 playlist has a video attribute of 24P or 60i, the video attributes of the whole digital
streams constituting the playlist are regarded as 24P or 60i. With this structure,
even if only one of a plurality of digital streams constituting a playlist includes a
60P video stream, the playlist as a whole is treated as a "playback path having the
60P video attibute", and it is excluded fi-om the playback-target playback path when
15 the first play title or the top menu title is selected.
[0084]
The following point out some requirements from the standpoint of the
playitem information. According to the standard for the application layer of the
Blu-ray disc, the following items in a plurality of pieces of playitem information in
20 the playlist information need to be set in the same manner.
-Video Codec
-Resolution
-Frame rate
-Aspect ratio
25 This, in principle, prevents one playback path from including both a
playitem having the 60P attribute and a playitem having another attribute. Thus, if
a plurality of pieces of playitem information constituting a playlist include even one
piece of playitem information permitting a playback of a 60P video stream, the
playlist version in the playlist information file becomes a new version number, and
30 in that case, the other pieces of playitem information having the new version number
30
in the playlist are treated as 60P. Since one playback path should not include both
a playitem having the 60P attribute and a playitem having another attribute, the
video stream attributes are united in a virtual manner as described in the following.
[0085]
5 FIG. 4 illustrates an improvement in a data structure of a 60P playlist. The
first row illustrates stream files. The second row illustrates clip information files.
The third row illustrates the playlist information composed of a plurality of pieces of
playitem information #1 to #3. The triangle signs attached to the playitem
information indicate corresponding pieces of mark information set in the playitem
10 information. The fourth row illustrates the internal state of the playback device.
[0086]
In the third row, the version number of the MPLS file, which is the playlist
version number, is set to a predetermined value to indicate to the playback device
that the playlist illustrated in FIG. 4 is a 60P playlist.
15 [0087]
Among a plurality of pieces of playitem information constituting the playlist
information in the third row, the last one, namely playitem information #3, specifies
a 60P video stream, and playitem information #1 and #2 specify 601 video streams
that are composed of interlace pictures and have the fi-ame rate of 60 Hz. However,
20 the stream attribute information included in clip information files #1 to #3 that
correspond to the playitem information #1 to #3 are united to "60P" in a virtual
manner. With this structure, the attribute of the whole playlist is set to the attribute
of the progressive pictures having the fi-ame rate of 60 Hz, namely the 60P video
attribute.
25 [0088]
Note that the reason for expressing the unity of the video attributes in the
clip information as "virtual" is that, according to the actual Blu-ray disc application
standard, there is a one-to-one correspondence between a plurality of pieces of
stream attribute information in the clip information file and a plurality of real
30 streams, and thus it is inconceivable that a false attribute is set in the tream attribute
31
infonnation. In FIG. 4, the video attribute of the clip infonnation file is set to
"60P". This is a special treatment in the case where the playlist is a 60P playlist.
[0089]
As described above, even if a 60P video stream is permitted to be played
5 back via clip information only by playitem infonnation, which constitutes only a
part of a playlist, the playlist as a whle is treated as a 60P playback path. Therefore,
the three video streams illustrated in FIG. 4 can be played back as far as the
playback device has the 60P capability as indicated in the fourth row thereof With
this structure, even when the playlist information includes a piece of playitem
10 information specifying a video stream that can be played back by a
non-60P-supporting playback device, when it is judged that the playback device
does not have the 60P capability, the 60? playlist is not played back.
[0090]
In this way, according to the present embodiment, when one of a plurality of
15 video shooting sections includes a locally dynamic movement of a subject, sections
around the section can be recorded on the recording medium as one playback path of
24P->60P->24P by setting the section to 60P and sections before and after the
section to 24P. This provides a recording format enabling a playback path to
include a locally high frame rate. Accordingly, this makes it possible to restrict the
20 consumption of the recording capacity to the minunu, while introducing a video
shooting of a 60P video stream.
[0091]
(Embodiment 5)
The present embodiment relates to an improvement in recording a digital stream
25 havmg an optional frame rate other than 60P. In the previous embodiment, when a
plurality of digital streams constituting a playlist include one 60P stream, the whole
playback paths defined by the playlist are regarded as having the 60P attribute.
[0092]
However, there are digital streams having an optional frame rate other than
30 60P, such as "SOP video stream". The "50P video stream" is a video stream
32
composed of progressive pictures and having the frame rate of 50 Hz. If a
playback path of the 50P video stream is treated as a "non-60P playback path", the
following may happen: when the first play title or top menu title is selected, the
playback path of the SOP video stream is selected, and the screen blacks out.
5 [0093]
It is therefore an object of the present embodiment to exclude a possibility
that a playback path of the 50P video stream is selected as a playback path of a
non-60P video stream.
[0094]
10 In the case where the above problem is solved in the phase of implementing
a recording medium, the recording medium in this phase is the recording medium in
which the progressive-optional-rate playback path is a progressive-first-optional-rate
playback path which is a playback path for playing back the progressive pictures at a
first optional rate, and the plurality of playback paths defmed in the playlist
15 information include, as another type of playback path, a
progressive-second-optional-rate playback path which is a playback path for playing
back the progressive pictures at a second optional rate only within a predetermined
geographical region, and one of the plurality of control programs instructs the
playback device to play back the progressive pictures at the second optional rate, on
20 a condition that the playback device has a capability to process the
progressive-first-optional-rate playback path and a capability to process the
progressive-second-optional-rate playback path. Solving the problem with the
above improvement of the structural elements is an aspect of solution to the problem
in this phase.
25 [0095]
In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the playback device in which the progressive-optional-rate
playback path is a progressive-first-optional-rate playback path which is a playback
30 path for playing back the progressive pictures at a first optional rate, and the
33
plurality of playback paths defined in the playlist inforaiation include, as another
type of playback path, a progressive-second-optional-rate playback path which is a
playback path for playing back the progressive pictures at a second optional rate
only within a predetermined geographical region, one of the plurality of control
5 programs instructs the playback device to play back the progressive pictures at the
second optional rate, on a condition that the playback device has a capability to
process the progressive-first-optional-rate playback path and a capability to process
the progressive-second-optional-rate playback path, the player setting register is a
first capability register indicating whether or not the playback device has a
10 capability to process the progressive pictures at the optional rate, the playback
device further comprises a second capability register indicating whether or not the
playback device has a capability to play back the progressive pictures at the second
optional rate, and when the playback device is instructed to play back the
progressive pictures at the second optional rate, the playback unit plays back the
15 progressive pictures at the second optional rate on a condition that the first
capability register indicates that the playback device has the capability to process the
progressive pictures at the optional rate and the second capability register indicates
that the playback device has the capability to play back the progressive pictures at
the second optional rate.
20 [0096]
In the case where the above problem is solved in the phase of implementing
a recording device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the recordmg device in which the progressive-optional-rate
playback path is a progressive-first-optional-rate playback path which is a playback
25 path for playing back the progressive pictures at a first optional rate, and the
plurality of playback paths defined in the playlist information include, as another
type of playback path, a progressive-second-optional-rate playback path which is a
playback path for playing back the progressive pictures at a second optional rate
only within a predetermined geographical region, and when a piece of playlist
30 information defining the progressive-second-optional-rate playback path for playing
34
back only within the predetermined geographical region is written onto the
recording medium, a control program, which instructs the playback device to play
back the progressive pictures at the second optional rate on a condition that the
playback device has a capability to process the progressive-first-optional-rate
5 playback path and a capability to process the progressive-second-optional-rate
playback path, is written onto the recording medium together with the piece of
playlist information.
In accordance with the above problem solving means, the present
embodiment introduces a "50P playlist". The 50P playlist is a playlist defined by a
10 playlist information file (MPLS file) in which the playlist version number is set to a
predetermined value indicating SOP. The SOP playlist includes not only a playlist
in which all playitems constituting thereof have a stream video attribute "SOP", but
also a playlist which includes one or more playitems that permit playback of SOP
video streams and one or more playitems that permit playback of 60P video streams.
15 This is because a SOP playlist is treated as a sub set of a 60P playlist.
[0097]
The reason for this is as follows. The 60P is seen as an extension of the
NTSC method adopting 60i. The 60i NTSC method is a world-wide television
broadcasting method, and thus the 60P is assumed to be used in a world-wide
20 geographical region.
[0098]
In contrast, SOP is seen as an extension of the PAL method adopting SOi.
The SOi PAL method is a European scanning method, and thus the use of SOP is
restricted to the geographical region of Europe. Tlie SOP, like the 60P, has an
25 optional fi-ame rate, but the usable geographical region is narrower than that of 60P.
For this reason, in the present embodiment, a playlist including both SOP and 60P is
treated as a SOP playlist, and the SOP playlist is treated as a sub set of the 60P
playlist. That is to say, the SOP playlist is dependent on the 60P playlist. The
stream selection table is set such that a playlist permitting a playback of a SOP
30 digital stream is no more treated as a non-60P playlist. This prevents a SOP video
35
stream from being played back when the first play title or the top menu title is
selected. This fUrther prevents a SOP video stream from being entered into the
video decoder of a playback device which does not have the 50P capability, thereby
preventing the video decoder from taking a heavy load.
5 [0099]
FIG. 5 illustrates an improvement in solving the problem with a data
structure of a 50? playlist. The first row illustrates stream files. The second row
illustrates clip information files. The third row illustrates the playlist information
composedofaplurality of pieces of playitem information #1 to #3. The fourth row
10 illustrates the internal state of the playback device. As illustrated in the third row,
the playlist version number in the playlist information is set to a predetermined
value indicating SOP, so that the playlist illustrated in FIG. S is defined as a SOP
playlist. Among a plurality of pieces of playitem information constituting the
playlist information, the last one, namely playitem information #3, specifies a 60P
15 video stream, but playitem information #1 and #2 specify SOP video streams as the
target of playback. However, the stream video attributes of the clip information
files corresponding to playitem information #1 to #3 are united to the SOP video
attribute in a virtual manner. This is because the playlist version in the playlist
information is set to the predetermined value indicating SOP. With this structure,
20 the attribute of the playlist as a whole is set to the SOP video attribute.
[0100]
A playlist, which includes one or more SOP video stream that constitute only
a part thereof, is, as a whle, treated as a SOP playlist since the playlist version in the
playlist information is set to the predetermined value indicating SOP. Therefore,
25 the three video streams illustrated in FIG. 5 can be played back as far as the
playback device has both the 60P capability and the SOP capability, as mdicated in
the fourth row thereof With this structure, even when the playlist information
includes a piece of playitem information specifying a video stream that can be
played back by a non-60P-supporting playback device, when it is judged that the
30 playback device lacks at least one of the 60P capability and the SOP capability, the
36
playlist having the 60P video attribute is not played back.
[0101]
As described above, by imposing a strict requirement that progressive
pictures having a second optional rate are not permitted to be played back unless
5 progressive pictures having a first optional rate can be played back, a playback path,
which includes both the first optional rate and the second optional rate as the
optional video attributes of fi-ame rates higher than 24P, is played back without
interruption. This promotes uniting various materials having various attributes into
one.
10 [0102]
(Embodiment 6)
The present embodiment relates to the 60P capability of the display device.
The display device manufactures have different atttitudes toward providing display
devices with the capability to display 60P. Some manufacturers have marketed,
15 fi-om many years ago, display devices supporting 60P video display, in prospect of
the demand for high quality coming in the future. On the other hand, other
manufacturers, who consider it best to produce products at the lowest cost, are
planning to market display devices that can display 60P video, in the future. In
these circumstances, some users may have a halfway coimection format between a
20 playback device and a display device. That is to say, a playback device having the
60P capability may be cormected with a display device not having the 60P capability.
The above-described embodiments leave a possibility that a 60P video stream may
be entered into a display device in the above-described halfway connection format
and the video may be displayed inappropriately.
25 [0103] '
It is therefore an object of the present embodiment to exclude a possibility
that video may be displayed inappropriately in a halfway system in which^ for
example, a 60P-supporting display device is connected with a non-60P-supporting
playback device.
30 [0104]
37
In the case where the above problem is solved in the phase of implementing
a recording medium, it is desirable to adapt the problem solving means to the phase
by imposing a limitation of the recording medium in which, when playing back the
progressive-optional-rate playback path, each of the plurality of control programs
5 judges whether or not a display device has a capability to process the
progressive-optional-rate playback path, and instructs the playback device to play
back the progressive-optional-rate playback path, on a condition that the display
device has the capability to process the progressive-optional-rate playback path.
[0105]
10 In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the playback device in which the player setting register
includes: a first capability register indicating whether or not the playback device has
a capability to process the progressive pictures at the optional rate; and a second
15 capability register indicating whether or not a display device has a capability to
display the progressive pictures at the optional rate, and when the playback device is
instructed to play back the progressive pictures at the optional rate, the playback unit
plays back the progressive pictures at the optional rate on a condition that the first
capability register indicates that the playback device has the capability to process the
20 progressive pictures at the optional rate and the second capability register indicates
that the display device has the capability to display the progressive pictures at the
optional rate.
[0106]
In the case where the above problem is solved in the phase of implementing
25 a recording device, it is desirable to adapt the problem solving means to the phase by
imposing a limitation of the recording device in which each of the plurality of
control programs is generated such that, when playing back the
progressive-optional-rate playback path, each of the plurality of control programs
judges whether or not a display device has a capability to process the
30 progressive-optional-rate playback path, and instructs the playback device to play
38
back the progressive-optional-rate playback path, on a condition that the display
device has the capability to process the progressive-optional-rate playback path, and
then the generated control programs are written onto the recording medium.
[0107]
5 In the present embodiment, a capability to process a 60P video stream is
divided into (i) a decode capability to decode a plurality of access units constituting
the GOPs of the 60? video stream at a time interval of 1/60 seconds, and (ii) a
presentation capability to display each group of 1920x1080 pixels representing
non-compressed pictures obtained by the decoding, at the time interval of 1/60
10 seconds, and the decode capability is set in the player setting register as a 60? video
stream capability, and the presentation capability is set in the display device.
The playback device obtains the "presentation capability to display each
group of 1920x1080 pixels at the time interval of 1/60 seconds" from the display
device connected with the playback device, via an inter-device interface such as an
15 HDMI. It is judged that a 60? playlist can be played back and the presentation
capability is provided when it is judged that both the 60? capability of the playback
device and the 60? display capability of the display device are valid.
[0108]
As one variation of the above structure, when it is judged that the 60?
20 display capability is invalid, the player device may convert the video data into 60i or
the like and output the convered video data to the display device. In this case,
when the player device can convert a 60? video stream to a 60i video stream or the
like, it is possible to set the 60? display capability to "valid" regardless of the actual
60? display capability of the display device connected with the player device, and
25 judge that the "presentation capability to display each group of 1920x 1080 pixels at
the time interval of 1/60 seconds" is "provided".
[0109]
Also, the 60? display capability may be set to "invalid", but a "60i60i
conversion capability flag" may be set in the display device. The player device
30 may obtain the flag via an inter-device interface, and when the obtained 60P>60i
39
conversion capability flag has been set to "valid", the player device may judge that
the "presentation capability to display each group of 1920x1080 pixels at the time
interval of 1/60 seconds" is "provided".
[0110]
5 As described above, according to the present embodiment, a
60P-video-attribute playlist is played back on a condition that both the playback
device and the display device have the 60P capability. With this structure, it is
possible to prevent progressive pictures from being supplied to the display device at
the frame rate of 60 Hz in a halfway connection format in which a playback device
10 having the 60P capability is connected with a display device not having the 60?
capability. It is possible o prevent a quality problem from occurring on the display
device side connected with the playback device.
[0111]
(Embodiment 7)
15 The present embodiment relates to exclusion of 60? titles. In a typical disc
structure, the top menu title is displayed for a user to select a video stream to be
played back. If the displayed top menu suggested the presence of a 60? playback
path that might be played back inappropriately, the structure would not dispel the
manufacturers's fear that progressive pictures might be started to be played back at
20 the frame rate of 60 Hz.
[0112]
It is therefore an object of the present embodiment to hide the presence of a
60? video sfream from users when the recording medium is loaded into a
non-60?-supporting playback device.
25 [0113]
In the case where the above problem is solved in the phase of implementing
a recording medium, the recording medium in this phase is the recording medium in
which a top menu displayed by the top menu title includes two or more button
objects which correspond one-to-one to two or more titles and each receive a
30 selection of a corresponding title on the top menu, the two or more titles include a
40
first-type title that instructs the playback device to play back the progressive pictures
at the optional rate and a second-type title that instructs the playback device to play
back the progressive pictures at a frame rate other than the optional rate or to play
back the interlace pictures, and a control program corresponding to the top menu
5 title sets a button object corresponding to the first-tj^e title among the two or more
button objects to an enable state when the playback device has a capability to
process the progressive-optional-rate playback path, and sets the button object
corresponding to the first-type title to a disable state when the playback device does
not have the capability to process the progressive-optional-rate playback path.
10 Solving the problem with the above improvement of the structural elements is an
aspect of solution to the problem in this phase.
[0114]
In the case where the above problem is solved in the phase of implementing
a playback device, it is desirable to adapt the problem solving means to the phase by
15 imposing a limitation of the playback device in which a top menu displayed by the
top menu title includes two or more button objects which correspond one-to-one to
two or more titles and each receive a selection of a corresponding title on the top
menu, the two or more titles include a first-type title that instructs the playback
device to play back the progressive pictures at the optional rate and a second-type
20 title that instructs the playback device to play back the progressive pictures at a
frame rate other than the optional rate or to play back the interlace pictures, a control
program corresponding to the top menu title sets a button object corresponding to
the first-type title among the two or more button objects to an enable state when the
playback device has a capability to process the progressive-optional-rate playback
25 path, and sets the button object corresponding to the first-type title to a disable state
when the playback device does not have the capability to process the
progressive-optional-rate playback path, and the playback device ftirther comprises:
a receiving unit configured to receive a user operation; and a graphics decoder
configured to decode a graphics stream and display a top menu including a plurality
30 of buttons, and change the plurality of buttons in state in accordance with the user
41
operation.
[0115]
In the case where the above problem is solved in the phase of implementing
a recording device, it is desirable to adapt the problem solving means to the phase by
5 imposing a limitation of the recording device in which a top menu displayed by the
top menu title includes two or more button objects which correspond one-to-one to
two or more titles and each receive a selection of a corresponding title on the top
menu, the two or more titles include a first-type title that instructs the playback
device to play back the progressive pictures at the optional rate and a second-type
10 title that instructs the playback device to play back the progressive pictures at a
frame rate other than the optional rate or to play back the interlace pictures, and a
control program, which sets a button object corresponding to the first-type title
among the two or more button objects to an enable state when the playback device
has a capability to process the progressive-optional-rate playback path and sets the
15 button object corresponding to the first-type title to a disable state when the
playback device does not have the capability to process the progressive-optional-rate
playback path, is generated, and the generated control program is made to
correspond to a top menu title in the index table, and then is written onto the
recording medium.
20 [0116]
The following describes the problem solving process performed by the
above problem solving means with reference to FIGs. 6A-6D.
[0117]
FIGs. 6A-6D illustrate the structure of the top menu. In FIG. 6A, a frame
25 win3 indicates a closeup of the top menu. The top menu in this example includes a
sports day button and a cultural fest button, wherein the sports day button receives
an instruction to fransition to the title 1 containing video of the sports day, and the
cultural fest button receives an instruction to transition to the title 2 containing video
of the cultural fest. When the sports day button is entered on the screen displayed
30 by the top menu title, a 60P video of the sports day having been recorded in 60P is
42
played back; and when the cultural fest button is entered, a 60P video of the cultural
fest having been recorded in 60i is played back.
[0118]
That is to say, the top menu includes the sports day button for receiving a
5 selection of the title 1 containing video of the sports day and the cultural fest button
for receiving a selection of the title 2 containing video of the cultural fest, and
00002.PRG, v^hich is a control program corresponding to the top menu title,
includes a code that changes the status of a button object depending on whether or
not the playback device has the 60P capability.
10 [0119]
FIGs. 6B and 6C illustrate the status change of the button object. FIG. 6B
illustrates a sample image of the top menu screen in which the sports day button is
not displayed since the playback device does not have the 60? capability. FIG. 6C
illustrates a sample image of the top menu screen in which the sports day button is
15 displayed in grayout since the playback device does not have the 60? capability.
[0120]
A specific example of the status change of the object is as follows. That is
to say, first it is judged by referring to the above-mentioned 60?-capability flag
whether or not progressive pictures can be played back at the frame rate of 60 Hz.
20 When it is judged that progressive pictures can be played back at the frame rate of
60 Hz, the top menu title is structured to display a top menu, as illustrated in FIG.
6A, that includes the sports day button for receiving an instruction to fransition to
the title 1 and the cultural fest button for receiving an instruction to transition to the
title 2. When it is judged that progressive pictures cannot be played back at the
25 frame rate of 60 Hz, the top menu title is structured to display a top menu, as
illustrated in FIG. 6B, that does not include the sports day button, but includes only
the cultural fest button for receiving an instruction to transition to the title 2.
[0121]
Also, as illustrated in FIG. 6C, the sports day button for receiving an
30 instruction to transition to the title 1 may be displayed in grayout. In this case, the
43
top menu is composed of the sports day button displayed in grayout and the cultural
fest button for receiving an instruction to transition to the title 2. As illustrated in
FIGs. 6B and 6C, a button for receiving a selection of a 60P title is not displayed, or
displayed in grayout. This prevents the 60P title from being played back when the
5 playback device does not have the 60P capability.
[0122]
As another method for notifying the user of the unavailability of the 60?
video playback, the content of display on the screen may be changed when the
button object is entered. FIG. 6D illustrates a sample of such a screen that is
10 displayed when the playback device does not have the 60? capability. As
illustrated in FIG. 6D, when the button object is entered, a screen indicating the
unavailability of the playback is displayed. With this structure, it is possible to
prevent a 60? stream from being sent into the video decoder even if the user selects
a title corresponding to a 60? playback path.
15 [0123]
As described above, it is possible to change the structwe of the top menu
screen, which manages the fransition to each title, depending on whether or not
progressive pictures can be played back at the frame rate of 60 Hz, by embedding,
into a button for receiving an instruction to transition to the title 1, any combination
20 of the above-described methods including "when the button for receiving an
instruction to fransition to the title 1 is pressed, an image is displayed to notify the
user that the player device cannot play back the title" (FIG. 6D). With this
structure, it is possible to prevent a 60? playback path from being played back by a
player device that does not support 60?.
25 [0124]
As described above, the structure of the top menu is changed depending on
whether or not the playback device has the 60? capability. With this structure, it is
possible to prevent the 60 Hz progressive pictures from being played back by a
playback device that does not support a progressive playback at an optional rate.
30 Also, a video stream in a video format that can be played back by a
44
non-60P-supportmg player device is provided as the video stream for displaying the
top menu title. With this structure, by referring to the top menu, the viewer can
recognize in a reliable manner what is recorded on the recording medium.
[0125]
5 (Embodiments)
The present embodiment describes a specific structure of the recording
mediums described in Embodiments 1 to 7.
[0126]
The present embodiment provides, as an aspect of the recording medium, a
10 recording medium on which are recorded: an index table; a plurality of digital
streams respectively including a plurality of video streams; a plurality of pieces of
playlist information respectively defining a plurality of playback paths of the
plurality of video streams; and a plurality of control programs, wherein the plurality
of video streams include (i) a video stream that is composed of progressive pictures
15 and has a mandatory fi-ame rate, (ii) a video stream that is composed of interlace
pictures, and (iii) a video stream that is composed of progressive pictures and has an
optional fi-ame rate, among a plurality of titles described in the index table, a first
play title and a top menu title each correspond to a control program that instructs to
play back in accordance with a playback path defined with regard to the video
20 stream that is composed of progressive pictures and has the mandatory fi-ame rate or
the video stream that is composed of interlace pictures, and among the plurality of
control programs, one or more control programs, which respectively correspond to
one or more general titles that mclude neither the first play title nor the top menu
title, instruct to play back in accordance with a playback path defined with regard to
25 the video stream that is composed of progressive pictures and has the optional fi-ame
rate, and a control code, which instructs a playback device to play back the
progressive pictures on a condition that the playback device has a capability to play
back the progressive pictures at the optional fi-ame rate, is embedded m in each of
the one or more control programs. The format of the recording medium includes a
30 movie recording format and an AV recording format. It is desirable that the video
45
stream, the playlist information, the control program, and the index table are
recorded in a recording area to which the movie recording format is applied.
[0127]
The internal structure of the recording medium disclosed in the present
5 embodiment may include any of the problem solving means described in
Embodiments 1 to 7, or a combination of two or more of the problem solving means
described in Embodiments 1 to 7.
[0128]
Describing all of the possible internal structures incorporating the problem
10 solving means described in the above embodiments and combinations of two or
more of the problem solving means described therein would require an enormous
number of pages of the Description, and thus is not preferable. Thus, the following
discloses an internal structure that includes all the problem solving means described
in the above embodiments, as the representative thereof.
15 [0129]
First, an explanation is given of a specific system in which the above
recording medium is presumed to be used. FIG. 7 illustrates a home theater system
in which the recording medium, playback device and recording device described in
Embodiments ]h7 are used. The home theater system includes a removable
20 medium 1000, playback devices 1001 and 1002, a remote control 1003, and a
display device 1004.
[0130]
The removable medium 1000 is an optical disc or a semiconductor memory
card for storing stream files storing 60P video streams and stream files storing
25 non-60P video streams in an application format of a Blu-ray Recording disc, an
application format of a Blu-ray Readonly disc, and an application format of a
Blu-ray Rewritable disc.
[0131]
The playback device 1001 is a 60P player supporting 60P, reads a stream
30 file containing a 60P video stream or a stream file containing a non-60P video
46
stream in accordance with a program defined in any of the above application formats,
playlist information, or clip information, and performs a decoding process and a
playback process on the read stream file.
[0132]
5 The playback device 1002 is a non-60P player not supporting 60P, reads a
stream file containing a non-60P video stream in accordance with a program defined -
in any of the above application formats, playlist information, or clip information,
and performs a decoding process and a playback process on the read stream file.
The playback device 1002 does not perform the decoding process and the playback
10 process on a stream file containing a 60? video stream.
[0133]
The remote control 1003 allows the user to enter an operation to change the
status of the interactive screen, and includes a MoveUp key, a MoveDown key, a
MoveRight key, a MoveLeft key, and an Enter key. Here, a button included in the
15 interactive screen transitions among a normal status, a selected status and an active
status. The MoveUp key, MoveDovwi key, MoveRight key and MoveLeft key are
used by the user to change the status of the button as: the normal status —> the
selected status -> the active status. The normal status refers to a status in which
the button is merely displayed. In contrast, the selected status refers to a status in
20 which the button is focused by a user operation, but has not been entered. The
active status refers to a status in which the button is entered. The MoveUp key is
used to move the setting of the selected status fi-om a currently set button to another
button that is located above the currently set button in the interactive screen. The
MoveDown key is used to move the setting of the selected status fi-om a currently
25 set button to another button that is located below the currently set button; the
MoveRight key is used to move the setting of the selected status fi-om a currently set
button to another button that is located on the right-hand side of the currently set
button; and the MoveLeft key is used to move the setting of the selected status from
a currently set button to another button that is located on the left-hand side of the
30 currently set button.
47
[0134]
The Enter key is used to change the status of a button in the selected status
to the active status, namely to activate the button. Numeric keys "0" to "9" are
used to request a title direct search of a title having a corresponding title number.
5 [0135]
The display device 1004 receives pixel bit values of one screen from the
playback devices 1001 and 1002 via an inter-device interface, and displays an image
by driving display elements of the display panel in accordance with the received
pixel bit values. Note that 60 images are displayed per second in 60P, and 24
10 images are displayed per second in 24P.
[0136]
This completes the explanation of the home theater system.
[0137]
Next, a detailed explanation is given of the removable medium. In the
15 following explanation, a multi-layered optical disc is taken as one example of the
removable medium. The reason why the multi-layered optical disc is taken as one
example of the removable medium is that it has the strictest physical restriction for
writing and reading, and when writing to the multi-layered optical disc has no
problem, the writing is applicable to the other mediums. The structural elements as
20 the means for solving the problem are on the premise of the internal structure of an
existing recording medium. To enhance the understanding, the following describes
existing data elements that are the premise of the structural elements indispensable
for solving the problem.
[0138]
25 FIG. 8 illustrates an internal structure of a multi-layered optical disc.
[0139]
In this figure, the first row illustrates one example of a multi-layered optical
disc, and the second row shows tracks in the horizontally extended format though
they are in reality formed spirally in the recording layers. These spiral tracks in the
30 recording layers are treated as one continuous volume area. The volume area is
48
composed of a lead-in area, recording layers of recording layers 1 through 3, and a
lead-out area, where the lead-in area is located at the inner circumference, the
lead-out area is located at the outer circumference, and the recording layers of
recording layers 1 through 3 are located between the lead-in area and the lead-out
5 area. The recording layers of recording layers 1 through 3 constitute one
consecutive logical address space.
[0140]
The volume area is sectioned into units in which the optical disc can be
accessed, and serial numbers are assigned to the access units. The serial numbers
10 are called logical addresses. A data reading from the optical disc is performed by
specifying a logical address. Here, in the case of a read-only disc such as the
Blu-ray Readonly disc, basically, sectors with consecutive logical addresses are also
consecutive in the physical disposition on the optical disc. That is to say, data
stored in the sectors with consecutive logical addresses can be read without
15 performing a seek operation. However, at the boundaries between recording layers,
consecutive data reading is not possible even if the logical addresses are consecutive.
It is thus presumed that the logical addresses of the boundaries between recording
layers are registered in the recording device in advance.
[0141]
20 In the volume area, file system management information is recorded
immediately after the lead-in area. Following this, a partition area managed by the
file system management information exists. The file system is a system that
expresses data on the disc in units called directories and files. In the case of the
Blu-ray Readonly disc, the file system is a UDF (Universal Disc Format). Even in
25 the case of an everyday PC (personal computer), when data is recorded with a file
system called FAT or NTFS, the data recorded on the hard disk under directories
and files can be used on the computer, thus improving usability. The file system
makes it possible to read logical data in the same manner as in an ordinary PC, using
a directory and file structure.
30 [0142]
49
The fourth row shows how the areas in the file system area managed by the
file system are assigned. As shown in the fourth row, a non-AV data recording
area exists on the innermost circumference side in the file system area. Also, an
AV data recording area exists immediately after the non-AV data recording area.
5 The fifth row shows the contents recorded in the non-AV data recording area and the
AV data recording area. As shown in the fifth row. Extents constituting the AV
files are recorded in the AV data recording area. Also, Extents constituting
non-AV files, which are files other than the AV files, are recorded in the non-AV
data recording area.
10 [0143]
FIG. 9 illustrates the application format of the optical disc based on the file
system. This application format is called the BDMV format. The BDMV
directory is a recording area in which non-AV files and AV files are stored in the
directory/file structure of the BDMV format. It is presumed that data in the
15 application layer format of the Blu-ray ReadOnly disc is stored in the BDMV
directory, and thus a playback device supporting the Blu-ray disc accesses the
BDMV directory first when the recording medium is loaded therein.
Conventionally, in a device supporting a 1080/60P shooting, when a 1080/60
shooting mode is selected, a special recording area for the 1080/60 mode is created,
20 and a 60P video stream is stored in the special recording area. In contrast, in the
present embodiment, the 60P video stream is included in the BDMV directory for
the BDMV format.
[0144]
That is to say, the BDMV format of the present embodiment differs fi"om
25 conventional BDMV formats realized in the Blu-ray ReadOnly disc in that it
supports recording an AV stream that has a resolution of 1920x1080 and a fi-ame
rate of 60P. The following describes the directory structure of the BDMV format
in the present embodiment.
[0145]
30 In FIG. 9, the BDMV directory is a directory for storing data such as
50
I
management information and transport streams that can be written on the Blu-ray
Readonly disc. Five sub-directories called "BDJO directory," "JAR directory,"
"PLAYLIST directory," "CLIPINF directory," and "STREAM directory" exist
below the BDMV directory. Also, two types of files (i.e. index.bdmv and
5 MovieObject.bdmv) are arranged under the BDMV directory.
[0146]
The file "index.bdmv" (the file name "index.bdmv" is fixed) stores an index
table.
[0147]
10 The file "MovieObject.bdmv" (the file name "MovieObject. bdmv" is fixed)
stores one or more movie objects. The movie object is a program file that defines a
control procedure to be performed by the playback device in the operation mode
(HDMV mode) in which a command interpreter is a controller. The movie object
includes one or more commands and mask flags (a menu call mask flag, a title
15 search mask flag, etc.), where the mask flags each define whether or not to mask a
menu call or a title call when the call is performed by the user onto the GUI.
[0148]
The BDJO directory stores a program file with extension "bdjo"
(xxxxx.bdjo ["xxxxx" is variable, the extension "bdjo" is fixed]). This program
20 file stores a BD-J object, which is a program file defining a control procedure to be
performed by the playback device in an operation mode of an object-oriented
programming language.
[0149]
A substance of such a Java application is a Java archive file
25 (YYYYY.jar) stored in the JAR directory under the BDMV directory. An
application may be, for example, a Java^^ application that is composed of one or
more xlet programs having been loaded into a heap area (also called work memory)
of a virtual machine. The application is constituted from the xlet programs having
been loaded into the work memory, and data.
30 [0150]
51
The "PLAYLIST directory" stores a playlist information file with extension
"mpls" ("xxxxx.mpls" ["XXXXX" is variable, and the extension "mpls" is fixed]).
Such a playlist information file that is added with extension "mpls" and stored in the
BDMV directory is called "MPLS file". The version number of each MPLS file in
5 the PLAYLIST directory is set to a predetermined value that indicates a 60? playlist
or a 50P playlist.
[0151]
The "CLIPINF directory" stores a clip mformation file with extension "dpi"
("xxxxx.clpi" ["xxxxx" is variable, and the extension "dpi" is fixed]).
10 [0152]
The Extents constituting the files existing in the above directories are
recorded in the non-AV data area.
[0153]
The "STREAM directory" is a directory storing a stream file, and stores a
15 stream file ("xxxxx.m2ts" ["XXXXX" is variable, and the extension "m2ts" is
fixed]). The extension "m2ts" indicates that the stream file with this extension is in
a transport stream format. Such a stream file with extension "m2ts" is called
"M2TS file". A stream file and a clip information file having the same file name
make a pair. Such a pair of files (a stream file and a clip information file that have
20 the same file name and make a pair) is called "AV clip stream file".
[0154]
The following describes stream files storing digital streams. FIG. 10
illustrates the internal structure of the digital streams. As shown in FIG. 10, the
digital streams are composed of transport streams each of which includes one or
25 more of: a video stream; an audio stream; a presentation graphics (PG) stream; and
an interactive graphics (IG) stream.
[0155]
Each digital stream stored in the stream files is identified by a PID. For
example, an alignment 0x1011 is allocated to a 60P video stream, alignments
30 0x1100 to 0x11 IF are allocated to audio streams, alignments 0x1200 to 0xl21F are
52
allocated to presentation graphics, alignments 0x1400 to OxHlF are allocated to
interactive graphics streams, alignments OxlBOO to OxlBlF are allocated to video
streams used as child-screen video of the movie, and alignments OxlAOO to OxlAlF
are allocated to audio stream used as secondary audio mixed with the primary audio.
5 The headers of the TS packets constituting the elementary streams illustrated in FIG.
10 includes PIDs each including a value in the above numerical ranges.
[0156]
The following explains each of the elementary streams multiplexed in the
transport streams.
10 [0157]
- Video stream
The video stream is classified into a parent-screen video stream and a
child-screen video stream, wherein the parent-screen video stream and the
child-screen video stream represent the parent-screen image and the child-screen
15 image in the picture-in-picture (PiP), respectively. The parent-screen video stream
is a video stream including pictures in which a child screen is to be inserted in the •
picture-in-picture. Note that the playback device decides whether or not to perform
the picture-in-picture. When the playback device selects a non-picture-in-picture
display, only the parent-screen video stream is used to display images on the screen.
20 When the 60P video stream is adopted as the parent-screen video stream, the
parent-screen of the picture-in-picture is also a progressive picture and is displayed
at the jframe rate of 60Hz.
[0158]
The following describes a structure that is common to the parent-screen
25 video stream and the child-screen video stream. According to video compress
encoding methods such as MPEG-2, MPEG-4AVC, and SMPTE VC-1, data is
compressed in size by taking advantage of spatial and temporal redundancy of the
video. One method that takes advantage of temporal redundancy of the video is
inter-picture predictive encoding. According to the inter-picture predictive
30 encoding, when a certain picture is encoded, another picture to be displayed before
53
or after said certain picture is designated as a reference picture. An amount of
motion, which is a difference between the encoding-target picture and the reference
picture, is then detected, and the detected motion amount is compensated, with the
spatial redundancy between the pictures being removed. In this way, the data
5 amount is compressed.
[0159]
An intra-picture (I-picture) is a picture that is encoded by inter-picture
predictive encoding—i.e., by only using information present in itself without
referring to a reference picture. It should be noted that a "picture" is a unit of
10 encoding and denotes both of a frame and a field. A predictive picture (P-picture)
is a picture that is encoded by inter-picture predictive encoding by referring to
another picture that has already been processed. A bi-directive picture (B-picture)
is a picture that is encoded by inter-picture predictive encoding by simultaneously
referring to other two pictures that have already been processed. A Br-picture is a
15 B-picture that is referred to by another picture. Also, a frame in the case of the
frame structure and a field in the case of the field structure are called video access
units.
[0160]
FIGs. 11A and 1 IB illustrate typical three types of video streams. FIG.
20 llA illustrates the 60P video stream, and FIG. UB illustrates non-60P video
streams. The non-60P video streams include a 60i video stream illustrated in the
upper portion of FIG. 1 IB and a 24P video stream illustrated in the lower portion of
FIG. IIB. FIGs. 12A and 12B illustrate, in comparison, pictures displayed with
the 60P video stream and the 60i video stream. As illustrated in FIG. 12B, each
25 picture included in the 60i video stream is an interlace image. The interlace image
is composed of two fields: an odd field; and an even field. It is assumed here that
an image with horizontal lines, such as the one illustrated in FIG. 12B, represents an
interlace picture. On the other hand, it is assumed that an image without horizontal
lines, such as the one illustrated in FIG. 12A, represents a progressive picture.
30 [0161]
54
Also, compared with the 60P video stream which displays 60 images per
second as illustrated in FIG. IIA, the 24P video stream displays 24 images per
second as illustrated in the lower portion of FIG. 1 IB, providing a lower level of
reproduction of a small movement, and in this example, a jumpy movement of the
5 runners in the image. On the other hand, the 60P video stream, which displays
more than double the images of the 24P video stream per second, represents details
of the movement of the runners and conveys the dynamics.
[0162]
- Audio stream
10 The audio stream is classified into a primary audio stream and a secondary
audio stream. The primary audio stream is an audio stream that is to be a main
audio when the mixing playback is performed; and the secondary audio stream is an
audio stream that is to be a sub-audio when the mixing playback is performed. The
secondary audio stream includes information for downsampling for the mixing, and
15 information for the gain control.
[0163]
- Presentation graphics (PG) stream)
The PG stream is a graphics stream that can be synchronized closely with
the video, with the adoption of the pipeline in the decoder, and is suited for
20 representing subtitles. Since a close synchronization of the graphics stream and the
video is achieved by the pipeline decoding, the use of the PG stream is not limited to
the playback of characters such as the subtitle characters. For example, it is
possible to display a mascot character of the movie that is moving in
synchronization with the video. In this way, any graphics playback that requires a
25 close synchronization with the video can be adopted as a target of the playback by
the PG stream.
[0164]
- Interactive Graphics (IG) stream
The IG stream is a graphics stream which, having information for
30 interactive operation, can display menus with the progress of playback of the video
55
stream and display pop-up menus in accordance with user operations. The IG
stream includes a plurality of display sets, and each display set includes a plurality
of functional segments. The display sets includes an epoch-start display set, a
normal-case display set, an acquisition-point display set, and an epoch-continue
5 display set.
- [0165]
The plurality of functional segments belonging to these display sets fall into
the following types.
[0166]
10 (1) Object definition segment
The object definition segment defines the in-effect and out-effect of pages,
the normal, selected, and active statuses of the button members. The object
definition segments are grouped into those that define the same status of the button
members, and those that constitute the same effect image. The group of object
15 definition segments defining the same status is called "graphics data set". These
object definition segments define the graphics object by using a code value and a run
length of the code value.
[0167]
(2) Pallet definition segment
20 The pallet definition segment includes pallet data that indicates
correspondence among each code value, luminance, and red color difference/blue
color difference.
[0168]
(3) Interactive control segment
25 The interactive control segment includes a plurality of pieces of page
information. The page information is information that defines a screen
composition of the multi-page menu. Each piece of page information includes an
effect sequence, a plurality of pieces of button information, and a reference value of
a pallet identifier.
30 [0169]
56
The button information is information that realizes an interactive screen
composition on each page constituting the muhi-page menu by displaying the
graphics object as one status of a button member.
[0170]
5 The effect sequence constitutes the in-effect or the out-effect with use of the
graphics object, and includes effect information, where the in-effect is played back
before a page correspondmg to the page information is displayed, and the out-effect
is played back after the page is displayed.
[0171]
10 The effect information is information that defines each screen composition
for playing back the in-effect or the out-effect. The effect information includes: a
screen composition object that defines a screen composition to be executed in the
window (partial area) defined by the window defmition segment on the graphics
plane; and effect period information that indicates a time interval between the
15 current screen and the next screen in the same area. Among the plurality of object
definition segments, an object definition segment that defines the graphics object
used for the in-effect is disposed at a location that precedes an object definition
segment that defines the graphics object used for the button member.
[0172]
20 Each piece of button information in the page information is information that
realizes an interactive screen composition on each page constituting the multi-page
menu, by displaymg the graphics object as one status of a button member. The
button information includes button proximity information and a navigation
command. The button proximity information is information that specifies a button
25 to be set to the selected status when any of upward, downward, leftward and
rightward directions is specified by a key operation while a certain button is in the
selected status. The navigation command is a command that is executed when a
corresponding button member transitions to the active status. A typical navigation
command is a branch command. The branch commands include a title jump
30 command and a title call command. The title jump command is a command that
57
sets, in the title number register, a title number that is specified as an operand. The
title call command also sets, in the title number register, a title number that is
specified as an operand, but differs from the title jump command in that it is
accompanied with the status save process or the status restore process. In the status
5 save process, a plurality of values stored in a plurality of player status registers are
saved in a stack before a title number specified by an operand is set in the title
number register.
[0173]
In the status restore process, the values are restored from the stack to the
10 plurality of player status registers after a playback of a title with the title number
specified by the operand ends and the execution of the control program
corresponding to the title number ends. With the execution of the status save
process and the status restore process, a playback status before a call can be restored.
[0174]
15 (4) End segment
The end segment is a functional segment that is located at the end of a
plurality of functional segments belonging to one display set. The playback device
recognizes a series of segments from the interactive control segment to the end
segment as the functional segments that constitute one display set.
20 [0175]
This completes description of the elementary sfreams constituting the
transport streams that are digital streams. The following explains the process of
forming a transport stream. FIGs. 13A-13D illustrate the transport sfream
formation process. FIG. 13A illustrates how the transport sfream is formed by
25 multiplexing. First, a video stream 501 composed of a plurality of video frames is
converted into a PES packet sequence 502 and a TS packet sequence 503, and an
audio sfream 504 composed of a plurality of audio frames is converted into a PES
packet sequence 505 and a TS packet sequence 506. Similarly, a presentation
graphics stream 507 is converted into a PES packet sequence 508 and a TS packet
30 sequence 509, and an interactive graphics stream 510 is converted into a PES packet
58
sequence 511 and a TS packet sequence 512. A stream file 513, which stores the
digital stream, is one stream in which these TS packets are muhiplexed.
[0176]
FIG. 13B illustrates in detail how the video stream is stored in the PES
5 packet sequence. The first row of FIG. 13B indicates a video frame sequence of
the video stream. The second row of FIG. 13B indicates a PES packet sequence.
As indicated by arrows yyl, yy2, yyS and yy4 in FIG. 13B, the I-pictures, B-pictures
and P-pictures, which are a plurality of video presentation units in the video stream,
are separated from each other and stored in the pay loads of the PES packets. Each
10 PES packet has a PES header in which a PTS (Presentation Time-Stamp), which
indicates the presentation time of the picture, and a DTS (Decoding Time-Stamp),
which indicates the decoding time of the picture, are stored.
[0177]
FIG. 13C illustrates the format of the TS packets that are ultimately written
15 in the stream file storing the digital stream. Each TS packet is a fixed-length,
188-byte packet composed of a 4-byte TS header carrying information such as a PID
identifying the stream, and a 184-byte TS payload storing data. The PES packets
are stored in the divided form in the TS payloads. In the case of the Blu-ray
Readonly disc, each TS packet is attached a 4-byte TP_Extra_Header, thus
20 constituting a 192-byte source packet. The source packets are written in the stream
file. The TPExtraHeader stores information such as an ATS
(Arrival_Time_Stamp). The ATS shows a transfer start time at which the TS
packet is to be transferred to a PID filter of a system target decoder, which will be
described later. The source packets are arranged in the stream file as illustrated in
25 the lower row of FIG. 13C, where the numbers incrementing by one starting with the .
head of the stream file are called SPNs (Source Packet Numbers).
[0178]
In addition to TS packets of audio, video, subtitles and the like, the stream
file also includes TS packets of a PAT (Program Association Table), a PMT
30 (Program Map Table) and a PCR (Program Clock Reference). The PAT shows a
59
PID of a PMT used in the stream file storing the digital stream, and is registered
with the PID arrangement of the PAT itself The PMT stores the PIDs in the
streams of video, audio, subtitles and the like, and attribute information
corresponding to the PIDs. The PMT also has various descriptors relating to the
5 stream file storing the digital stream. The descriptors include copy control
information indicating whether or not copying of the stream file storing the digital
stream is permitted. The PCR stores STC time information corresponding to an
ATS showing when the PCR packet is transferred to a decoder, in order to achieve
synchronization between an ATC (Arrival Time Clock) that is a time axis of ATSs,
10 and an STC (System Time Clock) that is a time axis of PTSs and DTSs. A PAT
packet and a PMT packet are stored at the head of a transport stream of the stream
file storing the digital stream.
[0179]
FIG. 13D illustrates the data structure of the PMT in detail. A PMT
15 header is disposed at the head of the PMT. Information such as the length of data
included in the PMT is written in the PMT header. The PMT header is followed by
a plurality of table descriptors relating to the transport stream that is the digital
stream. Information such as the above-mentioned copy control information is
described in the table descriptors. The table descriptors are followed by a plurality
20 of pieces of stream information relating to the stream included in the stream file
storing the digital steam. The lead line cul indicates a closeup of the internal
structure of the stream information. Each piece of stream information is composed
of: a stream type for identifying, for example, the compression codec of the stream;
the PID of the stream; and a plurality of stream descriptors describing the attributes
25 (fi-ame rate, aspect ratio, etc.) of the stream. The number of stream descriptors is
equal to the number of streams that are present in the stream file storing the digital
stream.
[0180]
This completes the explanation of the transport stream. To realize random
30 accesses to the transport streams, clip information is provided in the recording
60
medium, as information dedicated to the transport streams. The clip information is
stored in the clip information file that is included in the above-described file
structure.
[0181]
5 FIG. 14A illustrates the internal structure of the clip information file. The
lead line cu2 indicates a closeup of the internal structure of the clip information file.
As indicated by this lead line, the clip information file is composed of clip
information, stream attribute information, an entry map, and sequence information.
[0182]
10 As indicated by the lead line cu3, the clip information is composed of a
system rate, a playback start time, and a playback end time.
[0183]
The system rate represents a maximum transfer rate at which the stream file
storing the digital steam is transferred to the PID filter of the system target decoder,
15 which is described below. The interval between the ATSs in the stream file storing
the digital steam is equal to or lower than the system rate. The playback start time
is the PTS of the first video frame in the stream file storing the digital steam. The
playback end time is obtained by adding a per-frame playback interval to the PTS of
the last video frame in the stream file storing the digital steam.
20 [0184]
The lead line cu4 in FIG. 14B indicates a closeup of the internal structure of
the stream attribute information. As indicated by the lead line cu4, the stream
attribute information is composed of a plurality of pieces of attribute information of
the respective streams included in the stream file storing the digital steam, the
25 plurality of pieces of attribute information being registered in one-to-one
correspondence with the PIDs. The stream attribute information includes
respective information of a video stream, an audio stream, a presentation graphics
stream, and an interactive graphics stream. The lead line cu5 indicates a closeup of
the internal structure of the video stream atfribute information. As indicated by this
30 lead line, each piece of video stream attribute information carries information
61
concerning what kind of compression codec the video stream was compressed with,
and the resolution, aspect ratio and frame rate of picture data that compose the video
stream.
[0185]
5 The lead line cu6 indicates a closeup of the internal structure of the audio
stream attribute information. As indicated by the lead line cu6, each piece of audio
stream attribute information carries information concerning what kind of
compression codec the audio stream was compressed with, how many channels are
included in the audio stream, what language the audio stream corresponds to, and
10 the sampling frequency of the audio stream. These information are used when, for
example, the decoder is initialized before the player is started to perform a playback.
[0186]
FIG. 14C illustrates the frame rates and resolutions indicated by the stream
attribute information. As illustrated in FIG. 14C, the frame rates include 23Hz,
15 24Hz (23.976Hz), 25Hz, 30Hz, 50Hz, and 60Hz. These frame rates are each
identified by a four-bit code.
[0187]
The resolutions include 1920x1080, 1280^720, 960x540, 720x576, and
720x480. For each of the resolutions 720x480, 720x576 and 1920x1080, the
20 progressive display method and the interleave display method are available. For
the resolution 1280x720, only the interleave display method is available. A
combination of a resolution and a display method is called a "video format", and the
video format is identified by a 4-bit format code.
[0188]
25 The clip information of the present embodiment is characterized in that it
makes it possible to set an image quality by the combination of resolution
1920x 1080 and frame rate 60P, which is represented as 1920x 1080/60P (in general,
it is often represented as "1080/60P"). This combination of the maximum
resolution and the highest frame rate provides a high-definition image recording.
30 [0189]
62
FIG. 14D illustrates the internal structure of the entry map. The lead line
cu7 indicates a closeup of the internal structure of the entry map. As indicated by
the lead line cu7, the entry map is composed of a plurality of entry maps that are
each provided for a PID value, and the entry maps each include entry map header
5 information 1101. Each entry map set for a PID value is map information that
indicates correspondence between PTSs and SPNs, wherein the PTSs are PTSs of
the video stream included in the stream file storing the digital steam.
[0190]
The lead line cu8 indicates a closeup of the internal structure of the
10 PTS-SPN pairs in the entry map. Each PTS here indicates a display time of an IDR
picture or a non-IDR I-picture that is at the head of a closed GOP or an open GOP
included in the video stream of MPEG4-AVC, or a display time of an I-picture of
MPEG2-Video.
[0191]
15 Each SPN provided in correspondence with a PTS in the entry map
indicates a source packet number of a source packet storing an access unit delimiter
that is positioned at the head in the access unit structure of the IDR picture or
non-IDR I-picture of MPEG4-AVC, or indicates a source packet number of a source
packet storing a picture header that is positioned at the head of an I-picture of
20 MPEG2-Video. Each pair of PTS and SPN provided in the same row in the entry
map is referred to as an entry point. Also, each entry point is identified by an entry
point ID (denoted as "EP_ID"), the entry point IDs incrementing by one with each
entry point, starting with "0". Usmg the entry map, the player can specify the
location of a file of the stream file storing the digital steam corresponding to an
25 arbitrary point on the playback axis of the video stream. For instance, when
performing a special playback such as fast forward or rewind, the player can
perform the random access efficiently without analyzing the stream file storing the
digital steam, by specifying, selecting and playing back an I-picture registered in the
entry map. An entry map is created for each video stream multiplexed in the
30 digital stream, and managed by the PID. The entry map header information 1101 is
63
stored at the head of each entry map. The entry map header information 1101
carries information such as: the PID of the video stream corresponding to the entry
map; and the number of entry points.
[0192]
5 Lastly, the sequence information is explained. The sequence information
indicates detailed information of ATC sequences and STC sequences that are
present in the stream file. More specifically, the sequence information indicates
the number of ATC sequences and the source packet numbers (SPN_ATS_start) of
the source packets that are at the head of each ATC sequence, as the detailed
10 information of ATC sequences. Also, the sequence information indicates, as the
detailed information of STC sequences, the playback start time (STC_Start_time)
and the playback end time (STC_End_time) of each STC sequence, and the number
of STC sequences.
[0193]
15 The following describes the playlist file (YYY.MPLS).
[0194]
The playback path defined by the playlist file is a so-called "multipath".
The multipath is a bundle of one or more main paths and one or more sub-paths,
wherein the main paths are playback paths defined for the main transport streams,
20 and the sub-paths are playback paths defined for the secondary transport streams.
The playlist information has a hierarchical structure including playitem information
and a clip stream file. This structure enables one transport stream to be referred to
by a plurality of pieces of playitem information by setting the ratio of the clip stream
file to the playitem information to "one-to-many". This makes it possible to create
25 a plurality of variations of a movie effectively by adopting, as a bank film, a
transport stream created for a playlist so that the bank film can be referred to by a
plurality of pieces of playitem information in a plurality of playlist information files.
FIG. 15A-15D illustrate one example of the internal structure of the playlist
information. As illustrated in FIG. 15A, the playlist information includes:
30 main-path information indicating the main paths that are playback paths defined for
64
the main transport streams; sub-path information indicating the sub-paths that are
playback paths defined for the secondary transport streams; playlist mark
information for setting entry marks and link points for the playback paths; and
metadata for picture-in-picture.
5 [0195]
As illustrated in FIG. 15B, a main path in the playlist is composed of one or
more playitems 1201, each playitem indicating a playback section of a clip stream
file. The playitems 1201 are identified by the playitem IDs, and are described in
the playlist in the order of playback. Also, the playlist includes playlist marks 1202
10 that indicate playback start points. The playlist marks 1202 can be set in the
playback section defined by the playitem. Each playlist mark is set at a position
fi-om where a playback can be started, so that the playlist marks are used for the
random access play. The playlist mark information includes: time stamps
indicating the positions of the mark points in the playitem; and attribute information
15 indicating attributes of the mark points. The attribute information indicates
whether a mark point defined by the playlist mark information is a link point or an
entry mark.
[0196]
The link point is a mark point that can be linked by the link command, but
20 cannot be selected when the chapter skip operation is instructed by the user. The
entry mark is a mark point that can be linked by the link command, and can be
selected even if the chapter skip operation is instructed by the user.
[0197]
The link command embedded in the button information of the IG stream
25 specifies a position for a random access playback, in the form of an indirect
reference via the playlist mark information.
[0198]
The following describes the content of the playitem information with
reference to FIG. 15C. The playitem includes a clip information specifier 1301, an
30 AV clip playback start time 1302, an AV clip playback end time 1303, user
65
operation control information 1304, a connection condition 1310, and a stream
selection table 1305. The clip information specifier 1301 specifies, by using a file
name of clip information (clip_information_fil6_nam6), a piece of clip information
that is to be referred to when a video stream is played back. The AV clip playback
5 start time 1302 specifies a playback start time (In_Time) on the STC time axis of the
video stream. The AV clip playback end time 1303 specifies a playback end time
(Out_Time) on the STC time axis of the video stream. Since the playback start
time and the playback end time are time information, the playback device obtains
SPNs that correspond to the specified playback start time and end time by referring
10 to the entry map of the clip information file, and performs the playback process by
identifying the read start position.
[0199]
When the control program operates in the command-interpreter-based
operation mode, the instruction to play back a 60P-video-attribute playlist may
15 include: a playitem playback command; a chapter playback command; and a resume
command, wherein the playitem playback command includes an operand specifying
a playitem number, the chapter playback command includes an operand specifying a
chapter number defined by the playlist mark information, and the resume command
instructs to play back the progressive picture at the frame rate of 60 Hz from a
20 resume point on the playlist. With the specification of the playitem number, the
playitem playback command can instruct to play back the progressive picture at the
frame rate of 60 Hz from the specified playitem. With the specification of the
chapter number, the chapter playback command can instruct to play back the
progressive picture at the frame rate of 60 Hz from a playlist mark having the
25 specified chapter number in the playlist. The playlist information, with definitions
in the playitem information and the playlist mark information, enables random
accesses at various positions in the playlist.
[0200]
The connection condition 1310 indicates the type of connection between the
30 playitem including the connection condition 1310 itself and a preceding playitem.
66
When set to "1", the connection condition 1310 of the playitem indicates that a
seamless connection is not ensured between of a digital stream specified by the
playitem and a digital stream specified by a preceding playitem that precedes the
playitem. When set to "5" or "6", the connection condition 1310 of the playitem
5 indicates that a seamless connection is ensured between a digital stream specified by
the playitem and a digital stream specified by a preceding playitem that precedes the
playitem. When set to "5", the connection condition 1310 indicates a seamless
connection associated with a clean break. Here, the "clean break" means that the
STC continuity may be interrupted between two succeeding playitems, that is to say,
10 the video display time at the end of the stream file storing the digital steam specified
by the preceding playitem may be discontinuous with the video display time at the
start of the stream file storing the digital steam specified by the subsequent playitem.
[0201]
However, there are restrictive conditions for the above. That is to say, the
15 digital streams need to be created in such a manner that the decoding performed by a
system target decoder, which is described below, does not fail when the digital
stream specified by the preceding playitem is input to the PID filter of the system
target decoder, then the digital stream specified by the subsequent playitem is input
to the PID filter and then a playback is performed. Also, the last audio fi^ame of the
20 digital stream specified by the preceding playitem needs to be overlapped, on the
playback time axis, with the first audio fi-ame of the digital stream specified by the
subsequent playitem.
[0202]
When set to "6", the connection condition 1310 indicates a "seamless
25 connection with continuous ATSs and PTSs", which means that a stream file, which
is obtained by linking together the stream file storing the digital steam specified by
the preceding playitem and the stream file storing the digital steam specified by the
subsequent playitem, must to be able to be played back as a stream file storing one
digital stream. That is to say, the ATSs and the PTSs are respectively continuous
30 between the stream file storing the digital steam specified by the preceding playitem
67
and the stream file storing the digital steam specified by the subsequent playitem.
[0203]
With regard to a 60P playlist, the connection condition is set as follows.
That is to say, when the two playitems to be played back successively have the same
5 video attribute such as 60i or 24P, the connection condition is set to 5 or 6. This is
because, to realize a seamless connection, the two succeeding playitems need to
have the same video attribute.
[0204]
This means that the connection condition is set to " 1 " when two succeeding
10 playitems respectively have video attributes 60P and 60i or 60? and 24P. In the
case of a 60P playlist, if it includes even one 60P playitem, the whole playitems are
60P, and basically the setting for the seamless connection is allowed. On the other
hand, for a combination of playitems having different video attributes, the
connection condition must be set to "1 (non-seamless)". Thus, a 60P playlist may
15 include a pair of succeeding playitems associated with both the seamless connection
and the non-seamless connection.
[0205]
This completes description of the connection condition. The following is a
detailed explanation of the stream selection table. The stream selection table 1305
20 includes a plurality of stream entries 1309, each of which is composed of a stream
selection number 1306, stream path information 1307, and stream identification
information 1308. The stream selection numbers 1306 are numbers that increment
by one with each insertion of a first stream entry 1309 in the stream selection table,
and are used for identification of streams in the player.
25 [0206]
The stream path information 1307 is information indicating which digital
stream the stream indicated by the stream identification information 1308 is
multiplexed on. For example, when the stream path information 1307 is "main
path", it indicates that the stream indicated by the stream identification information
30 1308 is multiplexed on the stream file storing the digital stream specified by the
68
playitem thereof, and when the stream path information 1307 is "sub-path ID=1", it
indicates that the stream indicated by the stream identification information 1308 is
multiplexed on the stream file storing the digital stream specified by a sub-playitem
corresponding to a playitem playback section in a sub-path identified by the
5 sub-path ID. The stream identification information 1308 is information such as
PIDs, and indicates streams multiplexed on the stream file storing the digital steam
that is referred to. Furthermore, attribute information of each stream is also
recorded in the stream entries 1309. Here, the attribute information is information
indicating the property of each stream, and for instance includes a language attribute
10 in the case of audio, presentation graphics, and interactive graphics.
[0207]
As shown in FIG. 15D, a playlist may include one or more sub-paths. The
IDs are assigned to the sub-paths in the order of their registration in the playlist.
These IDs are used as sub-path IDs for identifying the sub-paths. Each sub-path
15 indicates a stream playback path by a series of sub-playitems to be played back in
synchronization with the main path. Each sub-playitem, as is the case with the
playitem, has the clip information 1301, playback start time 1302 and playback end
time 1303. The playback start time 1302 and the playback end time 1303 of the
sub-playitem are expressed based on the same time axis as that of the main path.
20 [0208]
For example, if a certain stream entry 1309 registered in the stream
selection table 1305 of the playitem #2 shows sub-path ID=0 and presentation
graphics 1, the presentation graphics 1 multiplexed on the stream file storing the
digital steam of the sub-playitem #2 played back in synchronization with the
25 playback section of the playitem #2, among the sub-paths of sub-path ID=0, will be
played back in the playitem #2 playback section. Furthermore, each sub-playitem
includes a field called a sub-path connection condition, which has the same meaning
as a connection condition of a playitem. A digital stream on a boundary between
sub-playitems whose sub-path connection conditions are "5" or "6" needs to meet
30 the same conditions as for connection conditions "5" or "6".

CLAIMS
1. A recording medium on which are recorded:
an index table;
5 a plurality of digital streams respectively including a plurality of video
streams;
a plurality of pieces of playlist information respectively defining a plurality
of playback paths of the plurality of video streams; and
a plurality of control programs, wherein
10 the plurality of video streams include a video stream composed of
progressive pictures and a video stream composed of interlace pictures, and the
video stream composed of the progressive pictures has a mandatory rate or an
optional rate,
the mandatory rate is a frame rate at which any playback device can decode
15 and play back the progressive pictures, and the optional rate is a frame rate at which
a limited types of playback devices can decode and play back the progressive
pictures,
each of the plurality of control programs instructs a playback device to play
back one of the plurality of video streams in accordance with one of the plurality of
20 playback paths defined in the plurality of pieces of playlist information,
the index table indicates one-to-one correspondence between a plurality of
titles and the plurality of control programs, the plurality of titles including a first
play title and a top menu title, and
among the plurality of control programs, control programs corresponding to
25 the first play title and the top menu title exclude a progressive-optional-rate
playback path from a playback target, the progressive-optional-rate playback path
being a playback path for playing back the progressive pictures in the video sfream
at the optional rate.
30 2. The recording medium of Claim 1, wherein
1
among the plurality of control progfams, one or more control programs,
which respectively correspond to one or more general titles that include neither the
first play title nor the top menu title, instruct the playback device to play back the
video stream composed of the progressive pictures at the optional rate, on a
5 condition that the playback device has a capability to process the video stream
composed of the progressive pictures at the optional rate.
3. The recording medium of Claim 1, wherein
a plurality of mask flags are recorded on the recording medium as
10 corresponding to the plurality of titles, the plurality of mask flags each indicating
whether or not a search operation for searcliing a corresponding title is prohibited,
and
among the plurality of mask flags, one or more mask flags corresponding to
one or more titles that instruct to play back the progressive pictures at the optional
15 rate are set to indicate that search operations for searching the one or more titles are
prohibited.
4. The recording medium of Claim 1, wherein
the progressive-optional-rate playback path includes a first-attribute
20 playback section defined for a video stream that satisfies a condition of being
composed of progressive pictures and having the optional rate, and in a case where
the progressive-optional-rate playback path includes another playback section, a
video stream defined by the another playback section is regarded to satisfy the
condition, and information indicating presence of the first-attribute playback section
25 is set in a playlist that includes one or more first-attribute playback sections.
5. The recording medium of Claim 1, wherein
the progressive-optional-rate playback path is a
progressive-first-optional-rate playback path which is a playback path for playing
30 back the progressive pictures at a first optional rate, and the plurality of playback
>a6
paths defined in the playlist information include, as another type of playback path, a
progressive-second-optional-rate playback path which is a playback path for playing
back the progressive pictures at a second optional rate only within a predetermined
geographical region, and
5 one o^ the plurality of control programs instructs the playback device to
play back the progressive pictures at the second optional rate, on a condition that the
playback device has a capability to process the progressive-first-optional-rate
playback path and a capability to process the progressive-second-optional-rate
playback path.
10
6. The recording medium of Claim 1, wherein
when playing back the progressive-optional-rate playback path, each of the
plurality of control programs judges whether or not a display device has a capability
to process the progressive-optional-rate playback path, and instructs the playback
15 device to play back the progressive-optional-rate playback path, on a condition that
the display device has the capability to process the progressive-optional-rate
playback path.
7. The recording medium of Claim 1, wherein
20 a top menu displayed by the top menu title includes two or more button
objects which correspond one-to-one to two or more titles and each receive a
selection of a corresponding title on the top menu,
the two or more titles include a first-type title that instructs the playback
device to play back the progressive pictures at the optional rate and a second-type
25 title that instructs the playback device to play back the progressive pictures at a
frame rate other than the optional rate or to play back the interlace pictures, and
a control program corresponding to the top menu title
sets a button object corresponding to the first-type title among the
two or more button objects to an enable state when the playback device has a
30 capability to process the progressive-optional-rate playback path, and
12^
sets the button object corresponding to the first-type title to a
disable state when the playback device does not have the capability to process the
progressive-optional-rate playback path.
5 8. A playback device comprising:
a reading unit configured to read an index table from a recording medium;
a current number register storing a current title number which is a title
number of a current title;
an execution unit configured to execute a coiitrol program which is
10 indicated in the index table as corresponding to the ciurent title; and
a playback unit configured to play back a video stream selected fi-om a
plurality of video streams as instructed by the execution unit, in accordance with one
of a plurality of playback paths defined in playlist information,
wherein the plurality of video streams include a video stream composed of
15 progressive pictures and a video stream composed of interlace pictures, and the
video stream composed of the progressive pictures has a mandatory rate or an
optional rate,
the mandatory rate is a frame rate at which any playback device can decode
and play back the progressive pictures, and the optional rate is a frame rate at which
20 a limited types of playback devices can decode and play back the progressive
pictures,
the control program instructs the playback device to play back one of the
plurality of video streams in accordance with one of a plurality of playback paths
defined in a plurality of pieces of playlist information,
25 the index table indicates one-to-one correspondence between a plurality of
titles and the plurality of control programs, the plurality of titles including a first
play title and a top menu title, and
among the plurality of control programs, control programs corresponding to
the first play title and the top menu title exclude a progressive-optional-rate
30 playback path from a playback target, the progressive-optional-rate playback path
being a playback path for playing back the progressive pictures in the video stream
at the optional rate.
9. The playback device of Claim 8, wherein
5 among the plurality of control programs, one or more control programs,
which respectively correspond to one or more general titles that include neither the
first play title nor the top menu title, instruct the playback device to play back the
video stream composed of the progressive pictures at the optional rate, on a
condition that the playback device has a capability to process the video stream
10 composed of the progressive pictures at the optional rate,
the playback device further comprising:
a player setting register indicating one or more capabilities of the playback
device; and
a title management unit configured to, when the player setting register
15 indicates that the playback device has a capability to process the
progressive-optional-rate playback path, set a title number of a title corresponding to
the progressive-optional-rate playback path into the title number register in
accordance with the control program executed by the execution unit.
20 10. The playback device of Claim 8 further comprising
a receiving unit configured to receive a title search request fi-om a user,
wherein a plurality of mask flags are recorded on the recording medium as
corresponding to the plurality of titles, the plurality of mask flags each indicating
whether or not a search operation for searching a corresponding title is prohibited,
25 and
among the plurality of mask flags, one or more mask flags corresponding to
one or more titles that instruct to play back the progressive pictures at the optional
rate are set to indicate that search operations for searching the one or more titles are
prohibited.
30
11. The playback device of Claim 8, wherein
the progressive-optional-rate playback path includes a first-attribute
playback section defined for a video stream that satisfies a condition of being
composed of progressive pictures and having the optional rate, and in a case where
5 the progressive-pptignal-rats playl}ack path includes another playback section, a
video stream defined by the another playback section is regarded to satisfy the
condition, and information indicating presence of the first-attribute playback section
is set in a playlist that includes one or more first-attribute playback sections,
the playback device further comprising:
10 a playitem number register storing a current playitem number identifying a
current piece of playitem information among a plurality of pieces of playitem
information which respectively define a plurality of playback sections in one
playback path;
a demultiplexing unit configured to demultiplex, from a digital stream, one
15 or more elementary streams that are indicated in a stream selection table of the
current piece of playitem information as being permitted to be played back; and
a video decoder configured to decode a video stream included in the one or
more elementary streams.
20 12. The playback device of Claim 8, wherein
the progressive-optional-rate playback path is a
progressive-first-optional-rate playback path which is a playback path for playing
back the progressive pictures at a first optional rate, and the plurality of playback
paths defined in the playlist information include, as another type of playback path, a
25 progressive-second-optional-rate playback path which is a playback path for playing
back the progressive pictures at a second optional rate only within a predetermined
geographical region,
one of the plurality of control programs instructs the playback device to
play back the progressive pictures at the second optional rate, on a condition that the
30 playback device has a capability to process the progressive-first-optional-rate
<^
playback path and a capability to process the progressive-second-optional-rate
playback path,
the player setting register is a first capability register indicating whether or
not the playback device has a capability to process the progressive pictures at the
5 optional rate,
the playback device ftirther comprises
a second capability register indicating whettier or not ttie playbacic device
has a capability to play back the progressive pictures at the second optional rate, and
when the playback device is instructed to play back the progressive pictures
10 at the second optional rate, the playback unit plays back the progressive pictures at
the second optional rate on a condition that the first capability register indicates that
the playback device has the capability to process the progressive pictures at the
optional rate and the second capability register indicates that the playback device has
the capability to play back the progressive pictures at the second optional rate.
15
13. The playback device of Claim 8, wherein
the player setting register includes:
a first capability register indicating whether or not the playback
device has a capability to process the progressive pictures at the optional rate; and
20 a second capability register indicating whether or not a display
device has a capability to display the progressive pictures at the optional rate, and
when the playback device is instructed to play back the progressive pictures
at the optional rate, the playback unit plays back the progressive pictures at the
optional rate on a condition that the first capability register indicates that the
25 playback device has the capability to process the progressive pictures at the optional
rate and the second capability register indicates that the display device has the
capability to display the progressive pictures at the optional rate.
14. The playback device of Claim 8, wherein
30 a top menu displayed by the top menu title includes two or more button
objects which correspond one-to-one to two or more titles and each receive a
selection of a corresponding title on the top menu,
the two or more titles include a first-type title that instructs the playback
device to play back the progressive pictures at the optional rate and a second-type
5 title that instructs the playback device to play back the progressive pictures at a
frame rate other than the optional rate or to play back the interlace pictures,
a control program corresponding to the top menu title
sets a button object corresponding to the first-type title among the
two or more button objects to an enable state when the playbacic device has a
10 capability to process the progressive-optional-rate playback path, and
sets the button object corresponding to the first-type title to a
disable state when the playback device does not have the capability to process the
progressive-optional-rate playback path, and
the playback device frirther comprises:
15 a receiving unit configured to receive a user operation; and
a graphics decoder configured to decode a graphics stream and display a top
menu including a plurality of buttons, and change the plurality of buttons in state in
accordance with the user operation.
20 15. A recording device comprising:
an encoder configured to obtain a plurality of digital streams respectively
including a plurality of video streams by performing an encoding process;
a generating unit configured to generate a plurality of pieces of playlist
information corresponding to the plurality of digital streams, a plurality of control
25 programs, and an index table; and
a writing unit configured to write the plurality of digital streams, the
plurality of pieces of playlist information, the plurality of control programs, and the
index table onto a recording medium,
wherein the plurality of video streams include a video stream composed of
30 progressive pictures and a video stream composed of interlace pictures, and the
8-
video stream composed of the progressive pictures has a mandatory rate or an
optional rate,
the mandatory rate is a frame rate at which any playback device can decode
and play back the progressive pictures, and the optional rate is a frame rate at which
5 a limited types of playback devices can decode and play back the progressive
pictures,
each of a plurality of control programs instructs the playback device to play
back one of the plurality of video streams in accordance with one of the plurality of
playback paths defined in the plurality of pieces of playlist information,
10 the index table indicates one-to-one correspondence between a plurality of
titles and the plurality of control programs, the plurality of titles including a first
play title Eind a top menu title, and
among the plurality of control programs, control programs corresponding to
the first play title and the top menu title exclude a progressive-optional-rate
15 playback path from a playback target, the progressive-optional-rate playback path
being a playback path for playing back the progressive pictures in the video stream
at the optional rate.
16. The recording device of Claim 15, wherein
20 the index table is generated to make one or more general titles that include
neither the first play title nor the top menu title among the plurality of titles to
correspond to one or more control programs which instruct the playback device to
play back the video stream composed of the progressive pictures at the optional rate,
on a condition that the playback device has a capability to process the video stream
25 composed of the progressive pictures at the optional rate, and then the index table is
written on the recording medium.
17. The recording device of Claim 15, wherein
a plurality of mask flags are recorded on the recording medium as
30 corresponding to the plurality of titles, the plurality of mask flags each indicating
<^
whether or not a search operation for searching a corresponding title is prohibited,
and
among the plurality of mask flags, one or more mask flags corresponding to
one or more titles that instruct to play back the progressive pictures at the optional
5 rate are set to indicate that search operations for searching the one or more titles are
prohibited, and then the one or more mask flags are written on the recording
medium.
18. The recording device of Claim 15, wherein
10 when writing the progressive-optional-rate playback path, which includes a
first-attribute playback section defined for a video stream that satisfies a condition of
being composed of progressive pictures and having the optional rate, onto the
recording medium, when the progressive-optional-rate playback path includes
another playback section, a video stream defined by the another playback section is
15 regarded to satisfy the condition, and information indicating presence of the
first-attribute playback section is set in a playlist that includes one or more
first-attribute playback sections.
19. The recording device of Claim 15, wherein
20 the progressive-optional-rate playback path is a
progressive-first-optional-rate playback path which is a playback path for playing
back the progressive pictures at a first optional rate, and the plurality of playback
paths defined in the playlist information include, as another type of playback path, a
progressive-second-optional-rate playback path which is a playback path for playing
25 back the progressive pictures at a second optional rate only within a predetermined
geographical region, and
when a piece of playlist information defining the
progressive-second-optional-rate playback path for playing back only within the
predetermined geographical region is written onto the recording medium, a control
30 program, which instructs the playback device to play back the progressive pictures
|3<7
at the second optional rate on a condition that the playback device has a capability to
process the progressive-first-optional-rate playback path and a capability to process
the progressive-second-optional-rate playback path, is written onto the recording
medium together with the piece of playlist information.
5
20. The recording device of Claim 15, wherein
each of the plurality of control programs is generated such that, when
playing back the progressive-optional-rate playback path, each of the plurality of
control programs judges whether or not a display device has a capability to process
10 the progressive-optional-rate playback path, and instructs the playback device to
play back the progressive-optional-rate playback path, on a condition that the
display device has the capability to process the progressive-optional-rate playback
path, and then the generated control programs are written onto the recording
medium..
15
21. The recording device of Claim 15, wherein
a top menu displayed by the top menu title includes two or more button
objects which correspond one-to-one to two or more titles and each receive a
selection of a corresponding title on the top menu,
20 the two or more titles include a first-type title that instructs the playback
device to play back the progressive pictures at the optional rate and a second-type
title that instructs the playback device to play back the progressive pictures at a
frame rate other than the optional rate or to play back the interlace pictures, and
a control program, which sets a button object corresponding to the first-type
25 title among the two or more button objects to an enable state when the playback
device has a capability to process the progressive-optional-rate playback path and
sets the button object corresponding to the first-type title to a disable state when the
playback device does not have the capability to process the progressive-optional-rate
playback path, is generated, and the generated control program is made to
30 correspond to a top menu title in the index table, and then is written onto the
recording medium.