DESCRIPTION

FILE RECORDING APPARATUS, FILE RECORDING METHOD, PROGRAM OF
FILE RECORDING PROCESS, STORAGE MEDIUM IN WHICH A PROGRAM OF
FILE RECORDING PROCESS IS STORED, FILE PLAYBACK APPARATUS,
FILE PLAYBACK METHOD, PROGRAM OF FILE PLAYBACK PROCESS, AND
STORAGE MEDIUM IN WHICH A PROGRAM OF FILE PLAYBACK PROCESS
IS STORED
Background of the Invention
Technical Field
The present invention relates to a file recording
apparatus, a file recording method, a program of a file
recording process, a storage medium in which a program of a
file recording process is stored, a file playback apparatus,
a file playback method, a program of a file playback process,
and a storage medium in which a program of a file playback
process, which are applicable when a file in a QT format or
the like, in which a video data obtained by taking a moving
picture is recorded, is edited. According to the present
invention, an alternate track including video data is formed,
and the processing priority level for the alternate track is
defined thereby making it possible to provide to a user the
result of an effect process for an edited file in a QT
format or the like even when an apparatus used does not have
the capability of processing the effect.
Background Art
A Quick Time file format (hereinafter, referred to
simply as a "QT format") is widely used as a file format to
store multimedia data.
In the QT format, real data of a moving image, a still
image, and a sound are stored in the form of a collection of
blocks, and management information for managing the real
data is stored in the form of a collection of blocks
separately from the collection of blocks of the real data.
Hereinafter, such blocks will be referred to as atoms. An
atom of real data is referred to as a movie data atom. An
atom of management information is referred to as a movie
atom.
The movie atom includes various kinds of atoms
organized in a hierarchical form according to properties.
That is, management information associated with each
property is described in a box, and boxes of various levels
are hierarchically organized in a single movie atom. In the
movie atom, tracks are formed of hierarchical atoms of
management information corresponding to respective types of
real data. More specifically, when media data are video
data and sound data, a video track and an audio track are
formed in the movie atom whereby the real data of each type
in the movie data atom is managed by the corresponding track,
In the video track, not only video data of a moving picture
but also image data of a still image is managed. For
example, in data in which video data and audio data are
multiplexed as in MPEG2-PS (Program Stream) data, a track
assigned to describe management information thereof is not
classified as a video track but classified as a base media
track. However, regardless of which class the track is
classified, if the track is assigned to manage video data,
the track can be used to edit the corresponding real data.
Thus, hereinafter, the term "video track" is used to
describe a track for managing real data including video data
In this sense, in the following discussion, the base media
track is regarded as a video track. To describe a track
assigned to manage data including only video data but not
including sound data, the track will be explicitly denoted
as the "track associated with video".
In management of real data, it is possible to manage
not only a movie data atom stored together with a movie atom
but also a movie data atom separately stored in an external
file. That is, various kinds of media can be provided in
either a form in which a movie atom refers to an internal
movie data atom or in a form in which a movie atom refers to
an external movie data atom.
In the movie data atom, real data is divided into
samples which are minimum management units. In the QT
format, management information associated with each minimum
management unit of real data is described in the movie atom.
When a file is produced in the QT format, for convenience of
processing, as disclosed, for example, in Japanese
Unexamined Patent Application Publication No. 2001-94933,
samples are generally formed such that one sample includes
one frame or one GOP (Group Of Picture) which is a unit used
in displaying the real data.
In editing, when an effect is applied to video data in
the QT format, video data obtained as a result of applying
the effect is stored in a movie data atom, and a movie atom
corresponding to this video data is described in a video
track, thereby forming a file in which the editing is
reflected.
In the QT format, instead of storing a movie data atom
obtained as a result of editing including applying of an
effect, it is also allowed to applying an effect to original
video data stored in the movie data atom when the video data
is played back. When video data is edited in such a manner,
an effect track in which management information associated
with editing is formed in the movie atom, and the movie data
atom of the original video data is applied as an input
source to the effect track.
That is, as shown in Fig. 1, in such an editing process,
for example, when an effect such as filtering is applied in
a one source effect mode to a particular period T of a
streaming of one video data, a source track ST identifying
the real data of this period T is produced (Fig. 1(B)) in
accordance with management information (management
information based on a sample table described later)
associated with the video track VT (Fig. 1(A)) corresponding
to the real data of the original video data. Furthermore,
an effect track ET in which the specific process associated
with the effect to be applied to the source track ST is
produced (Fig. 1(C)).
In this case, in the QT file, the real data
corresponding to the original video track, that is, the
video track VT is sequentially played back. In parallel
with the playback according to the original track, the real
data identified by the source track ST is processed during
the period T according to the effect track ET while
sequentially playing back the real data. The video data
processed according to the effect track ET is output in
preference to the video data according to the video track VT.
Thus, in the one source effect mode, three tracks are
handled to perform the editing associated with the filtering.
Note that in Fig. 1, srcA is a name identifying the source.
On the other hand, as shown in Fig. 2, when editing is
performed, for example, in a two source effect mode such
that a transition effect such as cross fading is applied to
streamings of two video data, video tracks VT1 and VT2
corresponding to the real data of the two video data are
formed as original tracks (Figs. 2(A) and 2(B)), and source
tracks ST1 and ST2 associated with the effect in the period
T are produced according to the management information
associated with the two video tracks VT1 and VT2 (Figs. 2(C)
and 2(D)). Furthermore, an effect track ET (Fig. 2(E)) is
produced to define the specific process associated with the
effect to be applied to the video data identified by the
source tracks ST1 and ST2.
In this case, in the QT file, the real data
corresponding to the original tracks, that is, the video
tracks VT1 and VT2 are sequentially played back. In
parallel with the playback according to the original tracks,
the real data identified by the source tracks ST1 and ST2
are processed during the period T according to the effect
track ET while sequentially playing back the real data. The
video data processed according to the effect track ET is
output in preference to the video data according to the
video tracks VT1 and VT2. Thus, in the two source effect
mode, five tracks are handled in the transition editing
process.
In the QT format, the effect track for use in the
editing process is processed separately for management
information and real data. More specifically, types of
effects such as a chromakey effect used in editing of a file
are described in the effect track in the order in which
effects occur. On the other hand, in the movie data atom,
parameters associated with respective effects are described.
That is, in the QT format, the effect track is organized in
units of samples for each effect type and for each parameter
value associated with each effect.
In the QT file, in some cases, a new type of effect is
added when the version is upgraded. However, there is a
possibility that the new type of effect cannot be processed
by processing programs of old versions. In such a case, it
becomes possible to process the new type of effect in the QT
file by upgrading the processing program.
By applying a QT format to consumer video devices, it
becomes possible to provide video devices having an affinity
for computers. For example, if video data obtained by
taking a movie picture is recorded in a QT file, it is
possible to easily process the video data by using a
computer. Conversely, video data or audio data processed
using a computer can be played back using a consumer video
device.
In computers, as described above, when an effect which
is difficult to process occurs, it becomes possible to
process the effect if the processing program is upgraded.
However, it is very difficult to update processing programs
installed on consumer devices, and thus there is a
possibility that consumer devices encounter a difficulty in
processing effects.
In consumer devices, there is a possibility that an
original effect is added, which cannot be correctly
processed by a computer.
It is desirable to provide the result of any effect
process to users regardless of difference in processing
capability among devices or computers.
Disclosure of Invention
In view of the above, the present invention provides a
file recording apparatus, a file recording method, a program
of file recording process, a storage medium in which a
program of file recording process is stored, a file playback
apparatus, a file playback method, a program of file
playback process, and a storage medium in which a program of
file playback process is stored, which allow it to provide
to a user the result of an effect process for an edited file
in the QT format or the like regardless of a difference in
processing capability among apparatus.
To achieve the above object, the present invention
provides a file recording apparatus for editing video data
in accordance with a command input by a user and recording
the resultant edited video data in the form of a file, the
file including a block of real data management information
which is organized in a hierarchical structure and which
includes at least a source track in which management
information associated with the video data is described and
an effect track in which management information associated
with an effect to be applied to the video data is described,
and a block of real data including at least real data
associated with the effect track, the file recording
apparatus forming, in the block of management information,
at least an alternate track including video data equivalent
to video data obtained by performing a process according to
the effect track, and information indicating the processing
priority level assigned to the alternate track of the video
data with respect to the processing priority level assigned
to another track.
In this file recording apparatus according to the
invention, the alternate track including video data
equivalent to video data obtained by performing the process
according to the effect track, and the information
indicating the processing priority level assigned to the
alternate track of the video data with respect to the
processing priority level assigned to another track are
formed in the block of management information, thereby
making it possible to play back the file using a processable
alternate track detected by sequentially checking alternate
tracks in the order of priority levels based on the
information indicating the priority levels thus making it
possible even for an apparatus or a system which does not
have the capability of processing the effect to provide the
result of the effect process to a user. This makes it
possible to provide the result of an effect process for an
edited file in the QT format or the like to a user by using
various apparatus or systems which may be different in
processing capability.
The present invention also provides a file recording
method including editing video data in accordance with a
command input by a user and recording the resultant edited
video data in the form of a file, the file including a block
of real data management information which is organized in a
hierarchical structure and which includes at least a source
track in which management information associated with the
video data is described and an effect track in which
management information associated with an effect to be
applied to the video data is described, and a block of real
data including at least real data associated with the effect
track, the file recording method including the step of
forming, in the block of management information, at least
forming at least an alternate track including video data
equivalent to video data obtained by performing a process
according to the effect track, and information indicating
the processing priority level assigned to the alternate
track of the video data with respect to the processing
priority level assigned to another track.
The present invention also provides a program for
causing a computer to execute a file recording process
including editing video data in accordance with a command
5 input by a user and recording the resultant edited video
data in the form of a file, the file including a block of
real data management information which is organized in a
hierarchical structure and which includes at least a source
track in which management information associated with the
) video data is described and an effect track in which
management information associated with an effect to be
applied to the video data is described, and a block of real
data including at least real data associated with the effect
track, the program of the file recording process including
i the step of forming, in the block of management information,
at least an alternate track including video data equivalent
to video data obtained by performing a process according to
the effect track, and information indicating the processing
priority level assigned to the alternate track of the video
i data with respect to the processing priority level assigned
to another track.
The present invention also provides a storage medium in
which a program for causing a computer to execute a file
recording process is stored, the file recording process
including editing video data in accordance with a command
input by a user and recording the resultant edited video
data in the form of a file, the file including a block of
real data management information which is organized in a
hierarchical structure and which includes at least a source
track in which management information associated with the
video data is described and an effect track in which
management information associated with an effect to be
applied to the video data is described, and a block of real
data including at least real data associated with the effect
track, the program of the file recording process including
the step of forming, in the block of management information,
at least an alternate track including video data equivalent
to video data obtained by performing a process according to
the effect track, and information indicating the processing
priority level assigned to the alternate track of the video
data with respect to the processing priority level assigned
to another track.
As described above, the present invention provides the
file recording method, the program of file recording process,
and the storage medium in which the program of file
recording process is stored, which allow it to provide to a
user the result of an effect process for an edited file in
the QT format or the like regardless of a difference in
processing capability among apparatus.
The present invention also provides a file playback
apparatus adapted to play back video data recorded in the
form of a file on a recording medium and output the
resultant video data, the file including a block of real
data management information which is organized in a
hierarchical structure and which includes at least a source
track in which management information associated with the
video data is described, an effect track in which management
information associated with an effect to be applied to the
video data is described, and an alternate track including
video data equivalent to video data obtained by performing a
process according to the effect track, and information
indicating the processing priority level assigned to the
alternate track of the video data with respect to the
processing priority level assigned to another track, and a
block of real data including at least real data associated
with the effect track, the file playback apparatus
performing a process including the step of detecting a
processable alternate track in the order from the highest
priority level to lower priority levels based on the
information indicating the priority level and playing back
the file using the detected alternate track.
The present invention also provides a file playback
method of playing back video data recorded in the form of a
file on a recording medium and outputting the resultant
video data, the file including a block of real data
management information which is organized in a hierarchical
structure and which includes at least a source track in
which management information associated with the video data
is described, an effect track in which management
information associated with an effect to be applied to the
video data is described, and an alternate track including
video data equivalent to video data obtained by performing a
process according to the effect track, and information
indicating the processing priority level assigned to the
alternate track of the video data with respect to the
processing priority level assigned to another track, and a
block of real data including at least real data associated
with the effect track, the file playback method including
the step of detecting a processable alternate track in the
order from the highest priority level to lower priority
levels based on the information indicating the priority
level and playing back the file using the detected alternate
track. :
The present invention also provides a program for
causing a computer to execute a file playback process
including playing back video data recorded in the form of a
file on a recording medium and outputting the resultant
video data, the file including a block of real data
management information which is organized in a hierarchical
structure and which includes at least a source track in
which management information associated with the video data
is described, an effect track in which management
information associated with an effect to be applied to the
video data is described, and an alternate track including
video data equivalent to video data obtained by performing a
process according to the effect track, and information
indicating the processing priority level assigned to the
alternate track of the video data with respect to the
processing priority level assigned to another track, and a
block of real data including at least real data associated
with the effect track, the program of the file playback
process including the step of detecting a processable
alternate track in the order from the highest priority level
to lower priority levels based on the information indicating
the priority level and playing back the file using the
detected alternate track.
The present invention also provides a storage medium in
which a program for causing a computer to execute a file
playback process is stored, the file playback process
including playing back video data recorded in the form of a
file on a recording medium and outputting the resultant
video data, the file including a block of real data
management information which is organized in a hierarchical
structure and which includes at least a source track in
which management information associated with the video data
is described, an effect track in which management
information associated with an effect to be applied to the
video data is described, and an alternate track including
video data equivalent to video data obtained by performing a
process according to the effect track, and information
indicating the processing priority level assigned to the
alternate track of the video data with respect to the
processing priority level assigned to another track, and a
block of real data including at least real data associated
with the effect track, the program of the file playback
process including the step of detecting a processable
alternate track in the order from the highest priority level
to lower priority levels based on the information indicating
the priority level and playing back the file using the
detected alternate track.
As described above, the present invention provides the
file playback method, the program of file playback process,
and the storage medium in which the program of file playback
process is stored, which allow it to provide to a user the
result of an effect process for an edited file in the QT
format or the like regardless of a difference in processing
capability among apparatus.
Thus, the present invention makes it possible to
provide to a user the result of an effect process for an
edited file in the QT format or the like regardless of a
difference in processing capability among apparatus.
Brief Description of the Drawings
Fig. 1 is a diagram illustrating handling of a QT file
in terms of a one-source effect according to a conventional
technique.
Fig. 2 is a diagram illustrating handling of a QT file
in terms of a two-source effect according to a conventional
technique.
Fig. 3 is a video disk apparatus according to a first
embodiment of the present invention.
Fig. 4 is a schematic diagram illustrating a QT file.
Fig. 5 is a schematic diagram showing an atom structure
of a QT file.
Fig. 6 is a diagram showing an atom structure of a QT
file in terms of a one-source effect.
Fig. 7 is a diagram showing a part continued from Fig.
6.
Fig. 8 is a diagram showing an atom structure of a QT
file in terms of a two-source effect.
Fig. 9 is a diagram showing a part continued from Fig.
8 .
Fig. 10 is a diagram showing a part continued from Fig.
9.
Fig. 11 is a diagram illustrating a one-source effect
process performed in the video disk apparatus shown in Fig.
3 .
Fig. 12 is a diagram illustrating a two-source effect
process performed in the video disk apparatus shown in Fig.
3 .
Fig. 13 is a diagram showing a sample description atom
associated with a video track.
Fig. 14 is a diagram showing a sample description atom
associated with an effect track.
Fig. 15 is a diagram showing effect types.
Fig. 16 is a diagram showing an extension field of
sample description atom associated with an effect track.
Fig. 17 is a diagram showing the details of the effect
type field shown in Fig. 16.
Fig. 18 is a table showing contents of the parameter
flag shown in Fig. 16.
Fig. 19 is a table showing parameters corresponding to
effect types shown in Fig. 15.
Fig. 20 is a diagram showing a part continued from Fig.
ig. 21 is a diagram illustrating an alternate track.
Fig. 22 is a diagram illustrating a track header atom.
Fig. 23 is a diagram illustrating a user data atom;
Fig. 24 is a diagram illustrating a user data list in
the user data atom shown in Fig. 23.
Fig. 25 is a diagram illustrating a track property atom
in the user data list shown in Fig. 24.
Fig. 26 is a diagram illustrating a presentation type
in the track property atom shown in Fig. 25.
Fig. 27 is a diagram illustrating a QT file in terms of
a one-source effect.
Fig. 28 is a diagram illustrating a QT file in terms of
a two-source effect.
Fig. 29 is a diagram illustrating an effect process
performed in the video disk apparatus shown in Fig. 3.
Fig. 30 is a flow chart showing a process performed by
a system control microcomputer of the video disk apparatus
shown in Fig. 3.
Fig. 31 is a diagram showing an effect process
performed by a video disk apparatus according to an second
embodiment of the present invention.
Fig. 32 is a diagram showing an effect process
performed by a video disk apparatus according to an third
embodiment of the present invention.
Best Mode for Carrying Out the Invention
Embodiments of the present invention are described in
detail below with reference to drawings.
(1) Construction of Embodiments
(1-1) General Constrution of Video Disk Apparatus
Fig. 3 is a block diagram showing a video disk
apparatus according to an embodiment of the present
invention. In this video disk apparatus 1, a video signal
and an audio signal of a subject are respectively acquired
by imaging means and sound acquisition means (not shown),
and the video signal and the audio signal obtained as a
result of taking an image of the subject are recorded on an
optical disk 2. In a playback operation, the video signal
and the audio signal are read from the optical disk 2 and
output on a liquid crystal display panel serving as display
means or from a speaker serving as sound output means. The
video signal and the audio signal read from the optical disk
2 may be output to an external device as required. A user
is allowed to specify a particular part of the video signal
or the audio signal and edit it.
In the video disk apparatus 1, the video signal and the
audio signal obtained as a result of the image capturing
process are compressed into the MPEG format and are recorded
in a predetermined file format on the optical disk 2. In
this specific embodiment, the QT format is used as the file
format. Hereinafter, a file in the QT format will be
referred to simply as a QT file.
In the video disk apparatus 1, a video encoder 11
generates video data by converting a video signal DV1 from
analog form into digital form, encodes the video data into
the MPEG format, and outputs the resultant video data in the
form of an elementary stream DV.
An audio encoder 12 generates audio data by converting
an audio signal DAI of the taken movie from analog form into
digital form, encodes the audio data into the MPEG format,
and outputs the resultant audio data in the form of an
elementary stream DA.
When video disk apparatus 1 operates in a recording
mode, a file generator 15 generates a QT file under the
control of a system control microcomputer 19 by multiplexing,
in a synchronized form, the elementary streams DV and DA
output respectively from the video encoder 11 and the audio
encoder 12. More specifically, the file generator 15
multiplexes the input elementary streams DA and DV and
outputs a sequence of resultant data in the form of a movie
data atom. While outputting the sequence of data of the
movie data atom, data necessary to generate a movie atom
corresponding to the movie data atom is stored in an
appending manner in a memory 15A of the file generator 15.
When the recording of the movie data atom is completed, a
sequence of data of the movie atom is generated from the
data stored in the memory 15A, and the result is output.
A memory controller 18 switches its operation mode
under the control of the system control microcomputer 19.
In the recording mode, the memory controller 18 temporarily
stores, in a memory 17, the sequence of data of a QT file
output from the file generator 15 and outputs the data
stored in the memory 17 with proper timing so that the data
can be properly processed by the error correction
encoder/decoder 21. Conversely, in the playback mode,
conversely, data output from the error correction
encoder/decoder 21 is temporarily stored, and the stored
data is supplied as required to a file decoder 16 and the
system control microcomputer 19.
The error correction encoder/decoder 21 switches its
operation mode under the control of the system control
microcomputer 19. In the recording mode, the error
correction encoder/decoder 21 temporarily stores data output
from the memory controller 18 into a memory 20 and adds
correction code to the data. The error correction
encoder/decoder 21 reads the data stored in the memory 20 in
a particular order so as to obtain interleaved data, and
supplies the resultant data to a data modulator/demodulator
23. Conversely, in the playback mode, the error correction
encoder/decoder 21 temporarily stores, in a particular order,
data output from the data modulator/demodulator 23 in the
memory 20 so as to obtain deinterleaved data and supplies
the resultant deinterleaved data to the memory controller 18.
In this process, the error correction encoder/decoder 21
performs an error correction using the error correction code
added to the data in the recording process.
The data modulator/demodulator 23 switches its
operation mode under the control of the system control
microcomputer 19. In the recording mode, the data
modulator/demodulator 23 converts the data output from the
error correction encoder/decoder 21 into serial form and
modulates it. The data modulator/demodulator 23 supplies
the resultant modulated data to a magnetic field modulation
driver 24 or an optical pickup 33. In the playback mode,
the data modulator/demodulator 23 reproduces a clock signal
from a playback signal output from the optical pickup 33,
thresholds the playback signal into a binary signal, and
decodes it so as to obtain playback data corresponding to
the serial data generated in the recording process. The
resultant playback data is supplied to the error correction
encoder/decoder 21.
In a case in which a magnetooptical disk is used as the
optical disk 2, in the recording operation, the magnetic
field modulation driver 24 drives a magnetic head 32 in
accordance with the signal output from the data
modulator/demodulator 23 under the control of the system
control microcomputer 19. The magnetic head 32 is disposed
such that the magnetic head 32 faces toward the optical
pickup 33 via the optical disk 2 so that the magnetic head
32 applies a magnetic field, modulated according to the data
output from the data modulator/demodulator 23, to a spot
illuminated with a laser beam emitted from the optical
pickup 33. Thus, in the video disk apparatus 1 of the type
in which a magnetooptical disk is used as the optical disk 2,
data obtained as a result of taking a movie is recorded as a
file in the QT format on the optical disk 2 using the
thermomagnetic effect.
The optical disk 2 is a disk-shaped recording medium.
In the present embodiment, a rewritable optical disk such as
a magneto-optical (MO) disk or a phase change optical disk
is used. Under the control of a servo circuit 30, a spindle
motor 31 rotates the optical disk 2 at a constant linear
velocity (CLV), a constant angular velocity (CAV), or a zone
constant linear velocity (ZCLV) depending on the type of the
optical disk 2.
The servo circuit 30 controls the spindle by
controlling the operation of the spindle motor 31 in
accordance with signals output from the optical pickup 33.
The servo circuit 30 also controls the optical pickup 33 in
terms of tracking and focusing. The servo circuit 30 also
controls the seeking operation of the optical pickup 33 and
the magnetic head 32 and the focus search operation.
Under the control of the system control microcomputer
19, a drive control microcomputer 22 controls the seek
operation performed by the servo circuit 30.
The optical pickup 33 projects a laser beam onto the
optical disk 2 detects light reflected from the optical disk
2 by using a photosensor disposed in the optical pickup 33.
The optical pickup 33 generates various kinds of control
signals based on the light detected via the photosensor and
outputs the detected control signals. The optical pickup 33
generates the playback signal whose signal level changes in
accordance with a sequence of pits or marks formed on the
optical disk 2 and outputs the generated playback signal.
The optical pickup 33 operates differently depending on its
operation mode controlled by the system control
microcomputer 19. In the case in which a magnetooptical
disk is used as the optical disk 2, the operation in the
recording mode is performed such that the optical pickup 33
intermittently raises the intensity of the laser beam
striking the optical disk 2. Thus, in this video disk
apparatus 1, data obtained as a result of taking a movie is
recorded in the form of a pulse train on the optical disk 2.
In the case in which a phase change optical disk is used as
the optical disk 2, the optical pickup 33 raises the
intensity of the laser beam striking the optical disk 2 from
a low level, which is the same as the intensity level used
in the playback operation, to a high writing level in
accordance with the data output from the data
modulator/demodulator 23 thereby thermally recording the
data obtained as a result of taking a movie on the optical
disk 2.
In this video disk apparatus 1, as described above, the
video signal and the audio signal obtained as a result of
taking a movie are respectively compressed by the video
encoder 11 and the audio encoder 12 and output in the form
of elementary streams. The file generator 15 generates a
file in the QT format from the elementary streams output
from the video encoder 11 and the audio encoder 12. The
resultant file in the QT format is transferred to the
optical pickup 33 or to the optical pickup 33 and the
magnetic head 32 via the memory controller 18, the error
correction encoder/decoder 21, and the data
modulator/demodulator 23 and recorded on the optical disk 2.
In the video disk apparatus I, in the playback
operation, the playback signal output from the optical
pickup 33 is processed by the data modulator/demodulator 23,
and the result thereof is output as playback data. The
playback data is processed by the error correction
encoder/decoder 21, and thus the file in the QT format
recorded on the optical disk 2 is reproduced. The
reproduced data of the QT file is output via the memory
controller 18.
If the file decoder 16 receives the QT file data output
from the memory controller 18, the file decoder 16 separates
the received data into video data and audio data and outputs
elementary streams of video data and audio data. In this
process, the file decoder 16 acquires movie atom data via
the seeking process performed under the control of the
system control microcomputer 19, and the file decoder 16
outputs the elementary streams of video data and audio data
in accordance with management information described in the
movie atom.
Video decoders 13A and 13B decompress the elementary
streams of the video data and output the resultant video
data to the display means or an external device (not shown).
In this video disk apparatus 1, because the video decoders
13A and 13B are each capable of processing elementary
streams of the video data, it is possible to output
simultaneously and in parallel two different video data for
use in the two-source effect. An effect addition circuit 35
operates under the control of the system control
microcomputer 19 as follows. In a normal playback operation,
the effect addition circuit 35 directly outputs the video
data received from the video decoder 13A or 13B without
performing any process on the video data. However, when the
video data is edited, the effect addition circuit 35 adds or
does not add an effect, in accordance with a command issued
by the system control microcomputer 19, to the video data
output from the video decoder 13A or 13B and outputs the
resultant video data. In the two-source effect processing,
two video data output respectively from the video decoders
13A and 13B are converted into a single video data via the
effect processing performed by the effect addition circuit
35.
An audio decoder 14 decompresses the elementary stream
of the audio data output from the file decoder 16 and
outputs the resultant data to audio output means or the
external device (not shown). Thus, the video disk apparatus
1 has the capability of monitoring the video data played
back from the optical disk 2.
The system control microcomputer 19 is a computer
responsible for general control of the operation of the
video disk apparatus 1. In response to an operation
performed by a user, the system control microcomputer 19
executes a processing program stored in a memory (not shown)
to control the operation of various parts of the video disk
apparatus 1. More specifically, the system control
microcomputer 19 controls various operations including
recording of video data on the optical disk 2, playing back
the video data from the optical disk 2 and presenting the
played-back video data to a user, editing the video data,
etc.
Note that, in this video disk apparatus 1, the
processing program executed by the system control
microcomputer 19 is preinstalled in the video disk apparatus
I. Instead of preinstalling the processing program, the
processing program may be installed from a storage medium as
required. As for the storage medium for this purpose,
various kinds of storage media such as an optical disk,
magnetic disk, a memory card, or a magnetic tape may be used,
(1-2) QT File
Fig. 4 is a conceptual diagram showing the basic
structure of a QT file. The QT format is a file format
established as an extended function of an operating system
(OS) to make it possible to play back a moving picture or
the like without using special hardware. The QT format is a
time-base multimedia file format that allows real data in
various forms such as moving picture data, audio data, still
image data, text data, MIDI data etc. to be played back such
that the data in various forms are synchronized on a single
time base.
In the QT file, real data in various formats are
separately stored as media data in different tracks. Tracks
in which real data of video, sound, and text are
respectively referred to as a video track, a sound track
(audio track), and a text track. The QT file further
includes a track such as an MPEG2-PS (Program Stream) track
for managing multiplexed data of video data and audio data
such as MPEG2-PS data.
In the QT file Fl or F2, a set of such tracks forms a
movie data atom, and management information associated with
each track of the movie data atom is organized as a movie
atom. Note that atoms are also called boxes. The movie
data atom has an atom type name "mdat" and is also called a
media data. The movie atom has an atom type name "moov" and
is also called a movie resource.
The QT file may be in either an all-included form Fl in
which the movie data atom and the movie atom are all formed
in the same file or in an external-reference form F2 in
which the file includes only the movie atom. The externalreference
file F2 includes data that points to a movie data
atom existing in another file Fl. This allows the file F2
to be used in non-linear editing or the like. When a movie
data atom existing in an external file (such as the QT file
Fl) is managed by a movie atom, management information such
as a relative path or an absolute path indicating the
location thereof on a recording medium is also described in
the movie atom.
In the example of the all-included type file Fl shown
in Fig. 4, audio data (Al and A2) and video data (VI and V2)
are stored as media data in a movie data atom, and these
media data can be played back in accordance with management
information described in a movie atom stored in this file Fl
or in accordance with management information described in a
movie atom stored in an external reference type file F2.
Fig. 5 shows a general structure of a movie data atom
including video tracks and audio tracks and that of a movie
atom in a all-included type file, such as the file Fl. In
this figure, type names of respective atoms are also shown.
In the movie atom, track atoms (having a type name of
"trak") are substantially the same in terms of structure of
lower-layer atoms for video tracks and audio tracks, and
thus lower-layer audio track atoms are not shown in Fig. 5
for simplicity.
The movie atom includes atoms in which management
information, such as time information necessary in playback
of the file and position information identifying real data,
is described, wherein the atoms are organized hierarchically
according to properties. More specifically, the movie atom
includes a movie header atom, a track atom, and other atoms.
The movie header atom has type name "mvhd" and header
information is described therein. One track atom is formed
for each track in the movie data atom. In this specific
example, a video track atom and an audio track atom are
formed. Each track atom includes a track header atom, an
edit atom, a user data atom, and a media atom. In these
atoms of the track atom, information about corresponding
real data in the movie data atom is described.
In the track header atom, header information is
described. In the edit atom, information indicating the
temporal relationship with corresponding media data (real
data) is described. An edit list atom is formed as required,
and the time-base relationship between the track of the
present track atom and the media is described. In the user
data atom, additional user-defined data associated with the
track is written as required. In the user data atom, as
described in detail later, a plurality of additional data
can be described by using extension fields.
The media atom has a type name "mdia", and information
for managing the compression method, the storage location,
and the display time is described therein. The media atom
includes a media header atom, a media handler reference atom,
and a media information atom. In the media header atom,
header information is described. In the media handler
reference atom (denoted as "media handler" in Fig. 5), the
type of the corresponding real data is described whereby
making it possible to detect the data type such as video
data or audio data.
The media information atom is assigned "minf" as its
type name, and various kinds of information associated with
a sample, which is a minimum management unit, are described
in the media information atom. The media information atom
includes a media information header atom (such as a video
media information header or a sound media information header
(in the example shown in Fig. 5, a video media header))
corresponding to the real data, a data handler reference
atom (denoted as "data handler" in Fig. 5), a data
information atom, and a sample table atom.
The media information header atom is assigned "vmhd" or
"smhd" as its type name depending on whether its higherlevel
media handler reference atom indicates that the
corresponding track is a video track or an audio track, and
header information is described therein. In the case of a
track that manages data in which video data and audio data
are multiplexed, such as an MPEG2-PS (Program Stream) track
that manages MPEG2-PS data, a media information header atom
(base (general) media information header) is assigned "gmhd"
as its type name. In the data handler reference atom,
information associated with handling of the corresponding
real data is described. In the data information atom,
information indicating the storage location and storage
method of data to be referred to by the lower-level data
reference atom.
The sample table atom is assigned "stble" as its type
name, and information associated with each sample is
described therein. The sample table atom includes a sample
description atom, a time-to-sample atom, a sample size atom,
a sample-to-chunk atom, and a chunk offset atom.
In the sample description atom, information about
decoding, such as information indicating the data
compression method and associated information, is described.
In the time-to-sample atom, the time-base relationship
between each sample and decoding is described using a frame
rate. In the sample size atom, the data size of each sample
is described. In the sample-to-chunk atom, the relationship
between a chunk and samples included in that chunk is
described. Note that a chunk is a block including a set of
a plurality of samples, and each track data in the movie
data atom is formed in units of chunks. In the chunk offset
atom, information indicating the start position of each
chunk with respect to the start of the file is described
using an entry. In the QT format, in accordance with the
management information described in the sample table atom,
it is possible to sequentially play back respective samples
which are management units of the real data.
On the other hand, in the movie data atom, elementary
streams of video data and audio data, which are real data of
the QT file, are stored in the form of chunks, that is, sets
of samples, such that chunks of video data elementary
streams and chunks of audio data elementary streams are
alternately located.
In the present embodiment, the elementary stream of
audio data is encoded into a compressed form by the audio
encoder 12 in accordance with the standard of the MPEG1
Audio Layer 2, and the elementary stream of video data is
encoded into a compressed form by the video encoder 11 in
accordance with the standard of the MPEG2 Video. In the QT
file, various types of video data such as Motion JPEG video
data, Motion JPEG2000 video data, MPEG4 video data, or AVC
(Advanced Video Coding: MPEG4-partlO) video data and various
types of audio data such as Dolby AC3 audio data or ATRAC
(Adaptive Transform Acoustic Coding) audio data can be
employed. Video data and the audio data are not necessarily
needed to be in a compressed form, but uncompressed video
data or audio data such as linear data may also be employed.
In the QT file, it is also allowed to store data in which
video data and audio data are multiplexed, such as MPEG2-PS
(Program Stream) data.
In the QT format having a video track and an audio
track, an effect to be applied to video data may be
described in a track called an effect tract, as shown in
Figs. 6 to 10. Figs. 6 to 10 are diagrams showing file
structures in the QT format described using the C language,
for respective type names defined in the type field. Figs.
6 and 7 shows an example of a filtering process specified as
an effect process via an editing process. In this example,
only one video track is subjected to the effect process.
Such an effect process is called a one-source effect process
Specific examples of filtering processes on one video source
are monochrome conversion, sepia conversion, blurring, and
mosaicing.
Figs. 8 and 10 shows an example of a two-source effect
applied to two video tracks. Specific examples of twosource
effects are cross fading and wiping. Note that in
Figs. 6 to 10, only effect tracks and tracks (source tracks)
in which management information is described as to video
data to which effects specified in the effect tracks are to
be applied are shown, but a description associated with
audio tracks is not shown.
In the QT format, the effect track has the same media
type as the video track, and thus the effect track has the
same field structure as that of the video media. The source
track is a track for fetching video data to which the effect
is to be applied, and thus the source track can be of
various types depending on the video data. For example, the
source track can be of the video media type or of a media
type that allows it to handle, for example, MPEG2-PS
(Program Stream) data in which video data and audio data are
multiplexed. In the embodiment, it is assumed that the
source track is a track of the video media type.
That is, in the QT file, as shown in Fig. 6, following
a movie header atom of a movie atom, a track atom of a video
track is formed in the manner described above with reference
to Fig. 5. In the QT file, this video track is specified as
the source track. Following this, a track atom used as an
effect track (Track atom (effect)) is formed. As with the
video track, a track header atom, an edit atom, and a media
atom are formed in this effect track. In this effect track,
in addition to the track header atom, the edit atom, and the
media atom described above, a track reference atom (having a
type name of "tref") is also form.
In the track reference atom, information is described
to indicate the source track to which the effect is to be
applied. More specifically, in the track reference atom, a
track ID described in the track header atom (having a type
name of "tkhd") of the corresponding source track is
described in a track reference type atom (having a type name
of "ssrc) in this track reference atom. A track ID is an
identification code uniquely assigned to each track. Based
on this track ID, the effect track identifies the video
track to be processed.
In the case of a one-source effect as with the example
shown in Figs. 6 and 7, one of video tracks in a movie atom
is specified by a track ID described in a track reference
type atom. On the other hand, in the case of a two-source
effect as in the example shown in Figs. 8 to 10, two of
video tracks of a movie atom including two or more video
tracks are specified by two track IDs described in a track
reference type atom.
The effect track includes, as component elements of the
media atom of the video media type, a media header atom, a
media handler reference atom, a media information atom, and
a track input map atom (having a type name of "imap"). In
the track input map atom, information associated with the
source track to be input to the effect track and to be
subjected to the effect process is described in a QT atom
structure.
In the QT atom structure, as many track input QT atoms
(having a type name of "in" (first two characters of the
type name are expressed as 0x0000 in hexadecimal)) as
required are packed in a QT atom container (having a type
name of "sean") which is the highest-level atom in the QT
atom structure. Each track input QT atom includes an input
type QT atom (having a type name of "ty" (first two
characters of the type name are expressed as 0x0000 in
hexadecimal)) indicating that the input source is video
media, and a data source type QT atom (having a type name of
"dtst") indicating a name uniquely assigned to the source
track.
Note that in contrast to the one-source effect shown in
Figs. 6 and 7 in which there is only one track input QT atom,
there are two track input QT atoms in the case of the twosource
effects shown in Figs. 8 to 10.
Thus, in the QT file, source tracks ST, ST1, and ST2
are identified by the track reference atom (having a type
name of "tref") of the effect track ET and the track input
map atom (having a type name of "imap") as shown in Fig.
11(C) or Fig. 12(D). Fig. 11(C) shows an example of a
description for a one-source effect and Fig. 12(D) shows an
example of a description for a two-source effect. In Figs.
11(A) and (B) and Figs. 12(A) to (C) , shown are active data
of video data and effect tracks in which effects to be
applied to the video data are described.
In the effect track, information associated with the
effect is described in a sample description atom in a sample
table atom. Fig. 13 shows a sample description atom of a
video track. In Fig. 13 and following Fig. 14, the data
size of each field is described by a numeral enclosed
between parentheses.
In the sample description atom of the video track, the
size, the type name (stsd), and the version of the sample
description atom are described. The sample description atom
also includes flags. Furthermore, the number of entries
included in the sample description atom is described, and
there are as many video sample description entries, in which
relating information such as information indicating the data
compression method is described, as the number of entries.
In each entry (video sample description entry), the
size of the entry is described, and subsequently the data
compression method (data format) is described. Furthermore,
each entry (video sample description entry) has a field
(frame count) in which the number of frames assigned to one
sample is described as information associated with the data
format.
On the other hand, in the case of a sample description
atom of an effect track, as shown in Fig. 14 for comparison
with Fig. 13, the sample description atom includes fields
for describing the size, the type name (stsd), the version,
flags, and the number of entries as with the sample
description atom of the video track, and, subsequently,
include as many entries (effect sample description entries)
associated with the effect as required.
Each entry (effect sample description entry) associated
with the effect has a field (Size) for describing the size
of the entry and a field (Data Format) for describing the
type of the effect. As shown in Fig. 15, the effect type is
described in four alphabetical characters, and effect types
for a one-source effect include blurring (blur), color style
(solr), color tint (tint), edge detection (edge), emboss
(embs), HSL color balance (hslb), RGB color balance (rgbb),
sharpness (shrp), brightness and contrast (brco), etc.
Effect types for a two-source effect include chromakey,
cross fade, push, slide, alpha blending, zoom, SMPTE
(Society of Motion Picture and Television Engineers) wipe,
SMPTE iris, SMPTE radial, SMPTE matrix, etc., although a
further detailed description is not given herein. In the
present embodiment, the effect types further include
posterization (YPST), mosaic (MOSA), reverse (RGB Reverse
(Negative) (NEGA)), random dot (RDOT), and user defined
effect (UDEF).
The posterization (YPST) is a process of reducing the
number of brightness levels. The mosaic (MOSA) is a process
of conversion into mosaic. The reverse (RGB Reverse
(Negative) (NEGA)) is a process of positive-to-negative
conversion. The random dot (RDOT) is a two-source effect
process in which the screen is switched while randomly
placing dots. Provision of this effect in the present
embodiment allows an improvement in usability.
The user defined effect (UDEF) is a generic effect type
given to effects defined by manufacturers or the like that
provide devices or the like. The detailed type of the user
defined effect (having a type name of "UDEF") is defined
using an extension atom provided for use to describe
extension information of the data format. Only when the
detailed type is defined in this extension atom, the user
defined effect is actually effective.
The entry (effect sample description entry) of each
effect includes the same fields as those in an entry of a
video track, such as a reserved field, a data reference
index field, etc., and finally includes an extension atom
for use to describe extension information associated with
he data format.
The extension atom for use to describe the extension
information associated with the data format includes a
stream descriptor atom which is described as shown in Fig.
16. More specifically, the stream descriptor atom includes
a field for describing the size of the stream descriptor
atom, a field (strd) for describing the type of the stream
descriptor atom, a field for describing the version of the
stream descriptor atom, and a field for describing flags.
Following the flag field, there are fields for describing
specific extension information associated with the data
format. They are a data format field, a user defined effect
type field, and a parameter flag field. Note that the
version field and the flag field are reserved for future
extension, and 0x0 is assigned to both of these fields in
the present embodiment.
In the data format field, which is an extension field,
the same effect type (type name) as that described in the
data format field of the entry (effect sample description
entry) of the effect, which is one of effects described
above with reference to Figs. 14 and 15, is described.
In the user defined effect type field, a specific
effect type defined by a user is described. The user
defined effect type field has a length of 4 bytes, which is
divided into two parts each having a length or 2 bytes for
use to describe an owner ID and an effect ID, respectively,
as shown in Fig. 17.
The owner ID is a preassigned ID uniquely identifying a
manufacturer, and the effect ID is an ID identifying a
detailed effect name defined by the manufacturer. Thus, in
the present embodiment, a manufacturer is allowed to
implement various kinds of effects developed by the
manufacturer by using the QT format. That is, in the data
format field of the entry (effect sample description entry)
associated with the effect, user defined effect (UDEF) is
described as a general classification identifier to identify
that the present effect is a special effect defined by the
manufacturer. In the extension atom, the effect name field
is divided into two parts each having a length of two bytes
such that the owner ID and the effect ID are described
therein to identify the detailed effect type defined by the
manufacturer. This makes it possible to use the special
effect type defined by the manufacturer in a closed
environment dedicated to the manufacturer, and thus it is
possible to prevent conflict from occurring in terms of
codes used in this field. In practice, if it is allowed to
define an extension effect without using the owner ID and
the effect ID, troublesome management is needed to avoid
overlapped use of 4 alphabetic characters among
manufacturers and troublesome management is also needed in
terms of a serial application number. If it is further
allowed even to specify an extension effect defined by a
manufacturer only by using the data format field of the
entry (effect sample description entry) without introducing
the extension atom, a further difficulty can occur. When
the owner ID and the effect ID in this data field are
reserved, a value of 0x0 is written in each of them. In
this case, when user defined effect (UDEF) is set in the
effect type field of the data format shown in Fig. 14, use
of this effect type is disabled. If an existing effect type
other than the user defined effect (UDEF) is declared as the
effect type, values described in the owner ID and the effect
ID are meaningless. Thus, when an existence effect type
other the user defined effect (UDEF) is declared as the
effect type, 0x0 is usually set as owner ID and the effect
ID.
As shown in Fig. 18, the least significant bit of a
total of two bytes of the parameter flag is used to specify
whether an effect sample entry of an effect parameter set in
real data corresponding to this effect track is active or
not. In this setting, in the case in which no change in the
video data results from the effect process of the effect
sample entry of the corresponding parameter, the effect
sample entry of this parameter is set as null. That is, in
the present embodiment, by setting this flag, it is possible
to skip a useless process. High-order 15 bits of the
parameter flag are reserved for further extension.
The real data of the effect track assigned to the movie
data atom is stored in units of effect samples as with the
video data of the source track. In the effect track, the
effect type is defined on a type-by-type basis in the data
format field of the sample description atom, and parameter
data of the effect processing of the type defined in the
sample description atom is stored as the real data of the
effect track.
Fig. 19 and Fig. 20 show parameters applicable to the
movie data atom, for respective effect types. Each
parameter name is represented by four characters extracted
from a corresponding parameter type. Each parameter value
is stored in the movie data atom such that the type name
identifying the parameter type is used as a header
identifier.
For example, in the case of the effect type of
"brightness and contrast (brco)", brightness and contrast
can be set as parameters. The default value of each of
these parameters is 0. When the parameter values are set to
the default value, the contrast and the brightness are not
changed in the effect process. That is, no change occurs in
the output. When the effect process provides no effect, the
effect is called a null effect. On the other hand, when the
effect process provides some effect, the effect is called an
active effect. When an effect is set as a null effect, 0 is
set as the value of the parameter flag. On the other hand,
when an effect is set to be active, 1 is set as the value of
the parameter flag.
In the present embodiment, for effects which are set as
a null effects by corresponding parameter flags, the movie
data atom is not accessed to acquire the parameter thereof.
This allows simplification of the process.
In addition to the setting of the parameter flag to
define whether the effect is null or active, the track input
map atom and the track reference atom of the effect track
are set such that the effect track designates, as the source
track, the video track to be subjected to the effect process,
thereby making it possible to play back the video data with
the one-source effect by handling the two tracks, that is,
the effect track and the video track designated as the
source track, as shown in Fig. 11. This allows a reduction
in processing load imposed on the playback system. In the
case of video data with a two-source effect, it is possible
to playback the video data with the two-source effect by
handling three tracks as shown in Fig. 12, and thus a
reduction in processing load imposed on the playback system
is achieved.
(1-3) Maintaining Downward Compatibility
When a QT file is used in a consumer device, a problem
with compatibility in terms of effects can occur, as
described above. Furthermore, an effect defined by an owner
identified by an owner ID can be difficult to process
depending on a consumer device used. In Fig. 15, effects
whose type name is represented by upper case characters are
newly added effects, and there is a possibility that a
problem can occur in processing these effects.
In the present embodiment, avoid the above problems,
downward compatibility is achieved by properly setting an
alternate track and a user data atom so that the effect can
be correctly performed regardless of a difference in
processing capability among devices used.
The alternate track is defined in the conventional QT
format. When it is difficult for a decoder to decode a
track in the QT file in a playback operation, the alternate
track is used instead of the difficult track. In the QT
file, as shown in Fig. 21, when an effect track includes an
effect that can be difficult to process depending on a
decoder used, as is the case in which a movie atom is
described such that video data designated as a source track
is subjected to an effect process defined in a user defined
effect track (UDEF shown in Fig. 15), an alternate track is
defined for alternative use of the effect track (user
defined effect track).
An alternate track for alternative use of an effect
track is generally described in a similar manner to the
effect track. Furthermore, the effect parameters are
described in the movie data atom as represented by an arrow
A in Fig. 21. In the example shown in Fig. 21, the
alternate track for alternative use of the effect tract is
denoted as "alternate Effect".
The relationship between the alternate track and the
track to be replaced by the alternate track as required is
described in the flag field, the alternate group field, and
the layer field in the track header atom of the track atom
of the alternate track and also described in similar fields
of the track to be replaced by the alternate track as
required, thereby making it possible to detect and use the
alternate track when a difficulty occurs in playing back of
the QT file.
More specifically, as shown in Fig. 22, in the track
header atom, the size, the type name (tkhd), and the version
of the track header atom are described, and subsequently
flags are described. When a predetermined particular bit of
the flag has a value of 1, this track is set as an active
track that should be displayed. On the other hand, when
this particular bit has a value of 0, this track is regarded
as an inactive track that is not displayed although it exits
Thus, as shown in Fig. 21, when a user defined effect track
and an alternate track for alternative use of this user
defined effect track are formed, flags associated with them
are respectively set to 1 and 0.
In the track header atom, subsequently described are
creation time information, modification time information, a
track ID of corresponding real data, a reserved field, a
duration, a reserved field, and a layer that specifies the
positional layer in which the track should be displayed.
In the layer field, it is allowed to write a positive
or negative value or zero. When a plurality of tracks are
displayed at the same time, a track with the least layer
value is displayed on the top of the screen. For the other
tracks, a track with a greater layer value is displayed in a
lower layer. Thus, in the QT file, it is possible to
specify the displaying priority for the respective tracks by
setting the layer value, because tracks under another track
are hidden from users.
In the track header atom, an alternate group is
described. This alternate group is used to identify the
group to which the alternate track belongs. More
specifically, to identify that a particular track is an
alternate track for a particular original track, the
alternate group of the alternate track and the alternate
group of the original track are set to the same value. In
the example shown in Fig. 21, the alternate group is set to
a value of 1 so that the original track and the alternate
track for the original track can be detected from the
alternate group and the flag. In the track header atom,
subsequently other information such as a volume is described.
In the present embodiment, it is allowed to give a
further detailed definition of the alternate track by using
a user data atom. This makes it possible to achieve
downward compatibility in a more flexible manner. Fig. 23
shows an example of a user data atom. In the user data atom,
first, the size and the type name (udta) of the user data
atom are described. Subsequently, user data is defined in a
user data list. In this specific example, a UD AV
descriptor atom is placed in the user data list.
Fig. 24 shows an example of a UD AV descriptor atom.
As shown in Fig. 24, in the UD AV descriptor atom, the size
and the type name (mqds) of the UD AV descriptor atom are
first described, and then the property of a lower-level
track is described in a track property atom.
Fig. 25 shows an example of a track property atom. As
shown in Fig. 25, in the track property atom, the size, the
type name (tkpt), and the version of the track property atom
are first described. Subsequently, flags, a presentation
type, and priority are described.
In the presentation type field, as shown in Fig. 26,
either "orig" or "efct" is written. The character string
"orig" is written when the track atom to which the present
user data atom belongs is a source track to be subjected to
the effect process. On the other hand, the character string
"efct" is written when the track atom to which the present
user data atom belongs is a displayable track. This
character string is set not only to identify that the
present track is an alternate track for an effect track but
also to identify that the present track is a track of video
data obtained as a result of an effect process.
That is, in the present embodiment, when an alternate
track including video data representing the result of
application of the effect is formed as an alternative for
the effect track, in addition to an alternate track in which
an effect similar to the effect of the effect track is
described, the presentation type is described so as to
correctly identity these two types of track atoms.
The priority field is used to define the priority of
the process for the track atom to which the present data
atom belongs. When 0 is stored in this priority field, no
priority is defined. To define the priority, a positive
value equal to or greater than 1 is set in the priority
field. The smaller value, the higher priority. In the
present embodiment, the priority of the process is defined
such that, in the same alternate group, alternate tracks
that need higher processing power are assigned higher
priority.
Thus, in the present embodiment, when a plurality of
alternate tracks are formed for an effect track, use of the
priority field makes it possible to define the priority
among these alternate tracks whereby a selection in terms of
alternate tracks in a playback operation is performed in
accordance with the priority defined by a file producer.
That is, in the playback operation, a determination is made
as to whether an alternate track can be processed,
sequentially in the order of priority starting with the
alternate track that needs highest processing power.
(1-4) Processing of QT File
In the present video disk apparatus 1, in response to
an operation performed by a user, the video data recorded on
the optical disk 2 is edited nondestructively, and a
resultant file with downward compatibility is recorded on
the optical disk 2 in accordance with a command issued by
the user.
More specifically, in the present video disk apparatus
1, elementary streams DV and DA of video data and audio data
input as real data from the imaging means are multiplexed by
the file generator 15, and resultant multiplexed data is
recorded in the form of a sequence of movie data atoms on
the optical disk 2. When the real data is being recorded in
the form of the sequence of movie data atoms, corresponding
management information is sequentially acquired and stored
in the memory 15A of the file generator 15. After the
recording of the real data is completed, movie atoms are
produced based on the management information stored in the
memory 15A and recorded on the optical disk 2.
In the above process, the system control microcomputer
19 controls the general operation in terms of the recording
of the movie data atoms and the movie atoms by controlling
the operation of file generator 15 and processing the
management information stored in the memory ISA by executing
a particular processing procedure. Thus, in the video disk
apparatus 1, as shown in Fig. 27, a QT file F4 is produced
such that real data of video data and audio data obtained by
taking a movie picture are recorded in a movie data atom,
management information associated with the real data is
recorded in a video track vt and an audio track (not shown)
in a movie atom.
When editing is performed on the data recorded in the
above-described manner on the optical disk 2, the system
control microcomputer 19 displays a menu on a display screen
(not shown) to allow the user to select a command from the
menu and issue the selected command. Thus, the system
control microcomputer 19 accepts various commands indicating,
for example, an IN point, an OUT point, effects to be
applied to the original data. If the user issues a command
to record the edited data as a file on the optical disk 2,
the system control microcomputer 19 records the file on the
optical disk 2 in accordance with the command.
In the above-described process, the system control
microcomputer 19 produces an effect track ET on the basis of
the video track vt of the movie atom of the file F4
specified by the user as a file to be edited, and the system
control microcomputer 19 produces a file F5 in the external
reference form including the effect track ET such that the
effect track ET points to the movie data of the original
file F4.
More specifically, the system control microcomputer 19
makes a copy of the track atom of the video track vt of the
file F4 and records the copy as a video track VT on the
optical disk 2. In accordance with a command issued by a
user, an effect track ET including null effects having no
actual effect and an active effect that will result in an
actual effect is formed in association with the video track
VT, and the video track VT is specified as the source track
ST pointing to video data to be subjected to the effect
process according to the effect track ET.
For example, if the user issues a command to apply a
filtering effect in a period T, this period T is set as an
active effect period, and periods for which no effects are
specified are set as null effect periods. Furthermore, as
shown in Fig. 11, an entry is produced in a sample
description atom for an active effect sample and also for a
null effect sample, and an effect track is produced such
that the active effect and the null effect are described in
the respective entries. A track input map atom and a track
reference atom are set so as to specify the video track as
the source track.
Thus, when editing in terms of a one-source effect such
as that described above is performed, the system control
microcomputer 19 produces the file F5 as a result of editing
so that playback can be accomplished by handling only two
tracks, that is, the source track and the effect track.
This allows a reduction in processing load necessary in the
playback operation.
On the other hand, when a user issues a command to
apply a two-source effect, the system control microcomputer
19 produces a file F6 including an active effect track, a
null effect track, and a source track in accordance with the
edit command, as shown in Fig. 28. More specifically, track
atoms of two video tracks VT1 and VT2 to be subjected to the
two-source effect are produced by making copies, an active
effect period T, during which the effect should be subjected
to the video tracks VT1 and VT2, are set in accordance with
an IN point and an OUT point specified by the user, and
periods for which no effects are specified are set as null
effect periods.
Furthermore, as shown in Fig. 12, an entry is produced
in a sample description atom for an active effect sample and
also for a null effect sample, and an effect track is
produced such that the active effect and the null effect are
described in the respective entries. The setting in terms
of the null effect associated with the two-source effect is
made in a similar manner to the null effect associated with
the one-source effect. In this specific example, in the
first null effect sample in the effect track, ST1 is
specified as the source track, and ST2 is specified as the
source track in the null effect sample following the active
effect period. Furthermore, a track input map atom and a
track reference atom are set so as to specify the video
tracks VT1 and VT2 respectively as the source track ST1 and
ST2 .
Thus, when editing in terms of a two-source effect such
as that described above is performed, the system control
microcomputer 19 produces the file F6 as a result of editing
so that playback can be accomplished by handling only three
tracks, that is, the two source tracks ST1 and ST2 and one
effect track. This allows a reduction in processing load
necessary in the playback operation.
In the setting of such a null effect, the system
control microcomputer 19 sets the parameter flag (Fig. 18)
so that it is possible to identify whether an entry of
interest is of a null effect or an active effect only based
on management information of the movie atom without having
to refer to the parameter value in the movie data atom. In
the playback operation, the system control microcomputer 19
detects the null effect based on the parameter flag, and
properly handles the null effect without having to detect
the corresponding parameter. This allows a reduction in
processing load necessary in the playback operation.
While the system control microcomputer 19 makes the
setting such that the null effect can be handled based on
the parameter flag as described above, the system control
microcomputer 19 forms an effect sample by employing a
standard effect name (for example, Brightness and Contrast
(brco) and properly setting parameters (for examples such
that Brightness = 0 and Contrast = 0). Thus, the edited
files F5 and F6 can be played back without a problem even by
a conventional QT file processing application that does not
have the capability of handling the null effect only based
on the parameter flag.
Of various entries, the active entry is treated by the
system control microcomputer 19 such that the effect type is
set in accordance with the effect type selected by the user.
In the case in which the effect type is an original effect
defined by the manufacturer of the video disk apparatus 1,
the effect type is set as the user defined effect, and
furthermore, the detailed effect type is set by describing
the owner ID and the effect ID in the extension field. Thus,
in the present embodiment, it is possible to implement
various effects in a very flexible manner.
However, even when the effect track is produced in the
above-described manner, it is still difficult for a device
to play back the edited data, if the device is incapable of
interpreting and processing the effect described in the
effect track. Furthermore, in the case in which the effect
described in the effect track is a special effect defined by
the manufacturer associated with the owner ID and the effect
ID, it is difficult to play back the data by an optical disk
apparatus produced by another manufacturer or by a QT player
implemented on a computer using a QT file playback program.
To avoid the above problem, in accordance with a
command issued by a user, the system control microcomputer
19 records the file including the effect track produced in
the above described manner on the optical disk 2 in a form
in which downward compatibility is achieved.
In the downward compatibility file, as shown in Fig. 29,
first and second alternate tracks ATI and AT2 for a source
track ST and an effect track ET in accordance with a
predetermined setting or in accordance with a command issued
by the user. The first alternate track ATI is provided for
use by a playback apparatus which has the capability of
processing some effects but is not capable of processing all
effects settable in the video disk apparatus 1. That is,
the system control microcomputer 19 produces an effect track
that allows it to achieve an effect similar to the effect
that is difficult for the playback apparatus to process, and
the system control microcomputer 19 specifies this effect
track as the first alternate track ATI.
For such an effect for which an alternate track should
be provided, a type name expressed in four upper case
characters (Fig. 15) assigned in advance or selected by a
user is employed. In this specific example, the first
alternate track ATI is formed such that the mosaic (MOSA)
effect described in the effect track ET is replaced with the
blur effect and the alternate track ATI includes three
samples of blur, null, and tint, and parameters associated
with these three samples are described in the media data
atom.
On the other hand, the second alternate track AT2 is
provided for use by a playback apparatus that does not have
the capability of processing any effect. The system control
microcomputer 19 produces the alternate track AT2 by
sequentially playing back the video data corresponding to
the source track ST, applying the effect to the video data
by using the effect addition circuit 35 in accordance with
the description in the effect track ET, compressing the
video data output as a result of the effecting process from
the effect addition circuit 35, and recording the resultant
video data on the optical disk 2. In the example shown in
Fig. 29, the alternate track AT2 is produced such that the
video data obtained as a result of applying the specified
effect is recorded in the mosaic and tint periods, and, in
the null period, video data of the source track in the
corresponding period is recorded. The resultant video track
subjected to the effect process and recorded on the optical
disk 2 in the above-described manner is set as the second
alternate track AT2 by the system control microcomputer 19.
Thus, the system control microcomputer 19 produces a
plurality of alternate tracks such as alternate tracks ATI
and AT2 so that the file can be handled by a wide variety of
apparatus which are different in processing power.
Thus, in the present embodiment, when the QT file is
played back by the same video disk apparatus 1 as that which
has produced the QT file, the edited video data can be
played back by processing the source track ST and the effect
track ET. On the other hand, when the QT file is played
back by an apparatus or a system which has lower capability
than that of the video disk apparatus 1 and thus is
incapable of processing the effect track ET, the edited
video data is played back by processing the alternate track
ATI or AT2 instead of the effect track ET. When the QT file
is played back by an apparatus or a system which does not
have the capability of processing any effect and thus is
incapable of processing the effect track ET and the
alternate track ATI, the edited video data is played back by
processing the second alternate track AT2.
When the system control microcomputer 19 has produced
the plurality of alternate tracks ATI and AT2 in the abovedescribed
manner, the system control microcomputer 19
describes the relationship between the effect track ET and
the alternate tracks ATI and AT2 by setting the flag, the
alternate group, and the layer in the track header atom of
the effect track ET and the alternate tracks ATI and AT2
such that the flag of the effect track ET is set to 1, the
flag of the alternate tracks ATI and AT2 is set to 0, and
the alternate group is set to the same value of 1 for all
tracks, that is, the effect track ET and the alternate
tracks ATI and AT2. In this specific example, the value of
the layer has no influence on the playback operation, and
thus the layer is set to a predetermined arbitrary value.
On the other hand, the presentation type in the user
data atom is set such that a character string of "orig" is
set for the source track ST but a character string of "efct"
is set for the other tracks, that is, the effect track ET
and the alternate tracks ATI and AT2.
The priority is set such that the highest priority is
given to the source track ST and the priority is reduced in
the order the effect track ET, the first alternate track ATI,
and the second alternate track AT2.
Thus, in the present embodiment, a description is made
in the QT file that the QT file should be process such that
when the QT file is played back by an apparatus or a system
which has lower capability than that of the video disk
apparatus 1 and thus is incapable of processing the effect
track ET, the alternate track ATI should be processed in
preference to the alternate track AT2.
In the example shown in Fig. 29, the alternate tracks
are provided for the one-source effect. For a two-source
effect, a first and second alternate tracks can be provided
in a similar manner.
If a command is issued to play back a QT file edited by
setting an effect track in the above-described manner, the
system control microcomputer 19 controls the playback system
such that data described in a movie atom are sequentially
read from the QT file specified by a user, and a movie data
atom is played back in accordance with the data described in
the movie atom.
In the playback operation, if the QT file specified to
be played back is an edited file, the system control
microcomputer 19 plays back the source track based on the
data described in the track reference atom and the track
input map atom of the effect track. In this process, if the
QT file includes, in addition to a full original video track,
a source track produced by copying a part of the original
video track in a period in which a one-source effect or a
two-source effect should be applied, as shown in Figs. 1 and
2, the video track, the source track, and the effect track
are handled in accordance with the data described in the
edit atom of each track atom, and the video data of the
source track is subjected to the effect process according to
the effect track. By switching the layer between video data
of video tracks, it is possible to playback the vide data of
the QT file in the conventional form such that the video
data of the original video track is displayed on the top of
the screen in any period other than active effect periods,
and the video data obtained by performing the effect process
on the source track according to the effect track is
displayed on the top of the screen during active effect
periods.
On the other hand, in the case in which an original
video track is recorded in a source track and an effect
track including a null effect and an active effect is formed
as is the case with the QT file shown in Fig. 27 or 28, the
video data is output while applying the active effect and
the null effect recorded in the effect track to the video
data read from the source track. Thus, use of the QT file
according to the present embodiment of the invention makes
it possible to playback an edited result by handling only
two tracks for a one-source effect or only three two track
for a two-source effect. In contrast, in the case of a QT
file in the conventional form, it is needed to handle as
many tracks as three tracks or five tracks to playback an
edited result with a one-source effect or a two-source
effect. Thus, it is possible to reduce the processing load
imposed on the playback system or the system control
microcomputer 19 during the playback operation.
In processing associated with a null effect or an
active effect, the system control microcomputer 19
determines whether the sample description atom of the effect
track includes an extension field (stream descriptor atom),
and, if it is determined that the sample description atom
includes an extension field, the system control
microcomputer 19 detects the value of the parameter flag set
in the extension field and determines whether an effect of
interest is set to be active or null, based on the value of
the parameter flag. In a case in which the effect of
interest is set to be active, the data of the parameter
associated with the effect to be applied to the real data
recorded in the movie data atom is read, and the effect is
processed in accordance with the parameter. On the other
hand, in a case in which the effect of interest is set to be
null, the video data recorded in the source track is
directly played back without reading the parameter.
Thus, in the present video disk apparatus 1, as
described above, when an effect of interest is set to be
null, a parameter associated with this null effect set in a
movie data atom is not read, and any processing based on
this parameter is not performed. Thus, a reduction in
processing load is achieved.
Even in the case in which it is determined based on the
parameter flag that the effect of interest is determined to
be active and thus the corresponding parameter is read from
the movie data atom, if the parameter is set to a value that
does not cause the effect to create any change, the effect
of interest is regarded as equivalent to a null effect and
video data is played back from the source track. Even in
the case in which no parameter flag is set in an extension
field, if a null effect and an active effect are set in an
effect track corresponding to a video track (formed as a
source track) , it is possible to minimize the number of
tracks to be handled, and thus it is possible to minimize
the processing load.
Thus, when a given QT file is a file according to the
conventional QT format including no extension field, the
system control microcomputer 19 reads a corresponding
parameter and processes the effect in accordance with the
parameter as in the case in which it is determined based on
the parameter flag that the effect is set to be active.
When an effect specified in an effect track is applied
to video data depending on the type of the effect, if the
effect type is the user defined effect type, the system
control microcomputer 19 detects the owner ID and the effect
ID described in the extension field. If the video disk
apparatus 1 does not have the capability of handling the
effect identified by the detected owner ID and effect ID,
the system control microcomputer 19 may regard the effect as
a null effect and may directly output the video data without
applying any effect to the video data. On the other and,
when the video disk apparatus 1 has the capability of
handling the effect identified by the detected owner ID and
effect ID (the capability may be provided to the video disk
apparatus 1, for example, by preinstalling a program module
for processing the effect in the video disk apparatus 1),
the effect identified by the detected owner ID and effect ID
is applied to the video data and the resultant processed
video data is output.
The flow of the process associated with the effect
track ET performed by the system control microcomputer 19 is
shown in Fig. 30. When a user issues a command to play back
a QT file including an effect track ET, the system control
microcomputer 19 starts the process from step SP1. In step
SP2, the system control microcomputer 19 determines whether
it is possible to process an effect described in a default
effect track (an effect track whose corresponding flag is
set to 1). If the answer to step SP2 is affirmative, the
process proceeds to step SP3 from SP2. In step SP3, a
general operation setup is performed such that the effect
described in the default effect track ET will be applied
when the QT file is played back. Thereafter, the process
proceeds to step SP4 in which the process is completed.
On the other hand, in the case in which the answer to
step SP2 is negative, the process proceeds to step SP5 from
SP2. In step SP5, the system control microcomputer 19
detects alternate tracks ATI and AT2, based on the value set
in the alternate group. The system control microcomputer 19
then checks the priority assigned to each alternate track to
detect an alternate track with next highest priority.
The system control microcomputer 19 determines whether
it is possible to process the effect described in the
detected alternate track with next highest priority. If the
answer affirmative, the process proceeds to step SP7 from
SP6. In step SP7, a general operation setup is performed
such that the effect described in the alternate track with
next highest priority will be applied when the QT file is
played back. Thereafter, the process proceeds to step SP4
in which the process is completed. In this case, the system
control microcomputer 19 applies the effect described in
this alternate track instead of the effect described in the
default effect track ET to the video data read from the
source track ST.
On the other hand, when the answer to step SPG is
negative, the process proceeds to step SP9 from SP6. In
step SP9, the system control microcomputer 19 determines
whether the process is completed for all alternate tracks
belonging to the same alternate group. If the answer is
negative, the process returns from step SP9 to SP5, the
process described above is performed for an alternative
track with further lower priority. On the other hand, if
the answer to step SP9 is affirmative, the process proceeds
to step SP4 from SP9. In step SP4, the system control
microcomputer 19 informs the user that the present file
cannot be played back. Thereafter, the process is ended.
If the QT file includes an alternate track in which a result
of applying an effect to a video track is recorded, the
video data with the effect can be played back by reading the
alternate track even by an apparatus which does not have the
capability (such as the capability of the video disk
apparatus 1) of processing effects. Therefore, the
affirmative answer to step SP9 can occur when the QT file
includes a special effect defined by another manufacturer
and does not include an alternate track in which a result of
applying the special effect to a video track is recorded.
(2) Operation of Embodiment
In the video disk apparatus 1, as described above, a
video signal DV1 acquired via the imaging means is
compressed by the video encoder 11, and the resultant
compressed video signal is input at a variable rate to the
file generator 15. Meanwhile, an audio signal DAI acquired
via a microphone or the like is compressed by the audio
encoder 12, and the resultant compressed audio signal is
input to the file generator 15. The file generator 15
converts the video signal and the audio signal into a QT
file. The QT file is then recorded on the optical disk 2
via the following process.
In the process performed by the file generator 15, the
video data and the audio data are reconstructed in the form
of a set of samples and a set of chunks. The video data is
interleaved in units of chunks and output in the form of a
movie data atom. The output video data is recorded on the
optical disk 2. While sequentially processing the video
data and the audio data in the above-described manner,
information necessary to play back each sample and each
chunk is acquired and stored as management information in
the memory 15A. When recording of the real data in the form
of the movie data atom is completed, the data of the
(
management information in the form of a movie atom is output
from the memory ISA to the recording means. Thus, the video
data and the audio data are recorded as the QT file on the
optical disk 2. Meanwhile, management information for
managing the video data and the audio data, which are real
data in the form of the movie data atom in the recorded QT
file, is created in the hierarchical form, and a video track
of management information associated with the video data and
an audio track of management information associated with the
audio data are formed in a movie atom.
If a user issues a playback command, the QT file
recorded on the optical disk 2 is played back under the
control of the system control microcomputer 19 as follows.
That is, the data of the movie atom is read from the optical
disk 2, and the data of the movie data atom is sequentially
read from the optical disk 2 in accordance with the
management information described in the movie atom. The
data of the movie data atom is decoded into the original
video data and audio data, and the resultant decoded video
data and audio data are output from the video decoders 13A
and 13B and the audio decoder 14. Thus, the original video
data and audio data obtained as a result of taking a movie
and recorded on the optical disk 2 are played back. Herein,
it necessary, editing is performed on the original video
data and audio data on the video disk apparatus 1.
If the user issues a command to edit the video data
recorded as the QT file, the movie atom of the QT file to be
edited is read out and a video track is formed by making a
copy of a part, to be edited, of the track atom of video in
the movie atom. In this case, the video track also serves
as a source track. In this video track, an absolute path is
described so as to point to the real data of the
corresponding video data in the original QT file, and a QT
file is created in the external reference form in which the
movie data atom of the original QT file is referred to.
Furthermore, in this QT file including the copied video
track, an effect track is formed in accordance with an IN
point and an OUT point specified by the user. In this
effect track, a null effect having no effect on the video
track and an active effect having an effect on the video
track are set in accordance with a command issued by the
user. Furthermore, the copied video track is specified as
the source track.
When a file according to the conventional QT format is
played back, it is necessary to handle an original video
track, a source track, and an effect track. In contrast,
when the QT file created in the above-described form is
played back by the video disk apparatus 1, it is possible to
play back the QT file only by handling the effect track and
the source track set as serving as a source for the effect.
Thus, a reduction in the processing load needed to play back
the edited video data is achieved.
That is, in the effect track, the track reference atom
and the track input map atom are described so as to point to
the source track, and the sample description atom is
described so as to identify effect types of all effects
including null effects. Furthermore, in accordance with the
setting described in the sample description atom in the
effect track, parameters of the respective effects are
assigned to the movie data atom of the edited QT file.
In the case in which the effect is a one-source effect,
the effect track ET is created such that one source track ST
is pointed to, and execution of processing is specified as
to null effects associated with the one-source effect and an
active effect associated with the one-source effect (Fig.
11). On the other hand, when the effect is a two-source
effect, the effect track ET is created such that two source
tracks ST1 and ST2 are pointed to, and execution of
processing is specified as to null effects associated with
the one-source effect and an active effect associated with
the two-source effect (Fig. 12) .
In the playback operation, when the effect is a onesource
effect (Fig. 27), while the sequence of video data
specified by the source track is played back,' the playedback
video data is subjected to the null effect process and
the result is output. In the active effect period T, the
video data read in accordance with the source track is
subjected to the active effect process, and the result is
output. Thus, it is possible to play back the edited video
data by handling only two tracks.
In the case of a two-source effect (Fig. 28), video
data specified by two source tracks are played back in the
order specified in the editing process, and one of video
data is output via the null effect process in periods other
than the active effect period T. In the transition period T,
the two video data are subjected to the active effect
process and the result is output. Thus, in this case, the
edited video data can be output by handling three tracks.
In the video disk apparatus 1, when the effect track is
created in the above-described manner, an extension field
associated with the corresponding effect is created, and
identification flags associated with the null effect and the
active effect are set in the created extension field. When
the edited QT file produced in the above-described manner is
played back in accordance with the identification flags, the
null effect can be processed without having to acquire the
parameter of the real- data set in the movie data atom, and
it is not needed to perform calculation associated with the
effect. This makes it possible to omit reading the
parameter from the movie data atom and performing processing
associated with the parameter, and thus it is possible to
reduce the processing load needed in playing back the edited
QT file.
That is, in the video disk apparatus 1, in the playback
operation, if the active effect is detected based on the
identification flag set in the extension field, the real
data of the movie data is accessed to acquire the parameter
associated with this active effect. The effect defined in
the entry is applied to the video data according to the
acquired parameter, and the resultant processed video data
is output. On the other hand, in this playback operation,
when the null effect is detected based on the identification
flag set in this extension field, accessing to the real data
of the movie data atom is stopped, and the video data
associated with the null effect is directly output without
processing the video data.
In contrast, when a file in the conventional QT file
formation including no extension field is played back, the
effect type is detected, and the parameter is acquired from
the movie data atom, the corresponding video data is
processed, and the result is output in a similar manner to
the conventional playback technique.
In the case in which the QT file includes an original
effect specific to the video disk apparatus 1, the effect
type filed in the entry of the effect is described to
indicate that the effect is of the user defined effect type,
and the owner ID and the effect ID are described in the
extension field to indicate the detailed effect type. Thus,
in the present embodiment, it is possible to implement
various effects developed by a manufacturer by using the QT
format.
However, when the QT file includes an effect defined by
another manufacturer using an owner ID and an effect ID, it
is impossible for the video disk apparatus 1 to play back
the QT file. Conversely, the QT file edited using the video
disk apparatus 1 cannot be played back by another video disk
apparatus or a computer.
To avoid the above problem, a user may issue a command
to record the QT file in the form with downward
compatibility (Fig. 29). In response to the command, the
video disk apparatus 1 creates an alternate track ATI by
replacing a special new effect or an effect specific to the
video disk apparatus 1 with a similar existing effect.
Furthermore, the user defined effect described in the effect
track ET is performed on the data played back from the
source track ST, and the resultant processed video data is
recorded in an alternate track AT2. These alternate tracks
ATI and AT2 and the effect track ET are set so as to belong
to the same alternate group, the flags are set so as to
indicate the status of the alternate tracks ATI and AT2 and
the effect track ET, the priority is set in the user data
atom to indicate the priority of these tracks, and the
presentation type is set so as to indicate that the
alternate track AT2 is a track in which real data of video
data is recorded in a similar manner to the source track ST,
but the alternate track AT2 provides the video data
subjected to the effect process when it is used instead of
the effect track ET. Thus, the video disk apparatus 1
creates the alternate tracks ATI and AT2 in the abovedescribed
manner and records the resultant nondestructively
edited data on the optical disk 2.
Thus, the video disk apparatus 1 is capable of editing
given video data in a nondestructive manner and recording
the resultant edited data on the optical disk 2, in the form
that allows wide variety of apparatus or systems having
different processing capabilities to play back.
For example, when a QT file to be played back is a file
recorded using the present video disk apparatus 1, the video
data specified by the source track ST is read and processed
according to the effect track ET, and the resultant edited
video data is presented to a user.
On the other hand, when a QT file produced using the
present video disk apparatus 1 is played back using a
computer, if an effect track ET specified by the flag and
the alternate group is processable by the computer, the
video data specified by the source track ST is read and
processed in accordance with the effect track ET, and the
resultant edited video data is presented to a user. However,
when the effect track ET is not processable by the computer,
the edited result of the QT file is played back using either
the alternate track ATI or AT2 and presented to the user.
Note that the QT file does not include information
indicating which one of a plurality of alternate tracks
should be selected by a QT file player installed on the
computer. Thus, the determination as to which one of the
plurality of alternate tracks is selected depends on the
setting of the QT file player installed on the computer.
However, in practice, when the computer is not capable of
processing the effect track ET which should be used if the
computer is capable of processing it, it is possible to
upgrade the QT file player installed on the computer to a
newer version capable of processing such an effect track.
Thus, it becomes possible to play back the QT file using the
effect track ET without using the alternate tracks.
When the QT file produced by the video disk apparatus 1
is played back using another video disk apparatus, or when
an optical disk recorded using another video disk apparatus
is played back using the present video disk apparatus 1, if
the effect track ET is processable, the data read from the
source track ST is subjected to the effect process according
to the effect track ET, and the result is presented to a
user.
However, when the effect track includes an effect that
is difficult to process, the video disk apparatus 1 selects
an alternate track ATI specified in the priority field as
having next highest priority, processes the data read from
the source track ST in accordance with the alternate track
ATI instead of the effect track ET, and presents the result
to a user. In this case, the user can enjoy the resultant
video subjected to the effect process performed by the
playback apparatus, although the effect is not perfectly
equal to the effect intended by the producer of the QT file.
When even the alternate track ATI is difficult to
process, an alternate track AT2 with lower priority is
selected. Because, in this alternate track AT2, video data
obtained as a result of applying the effect to the real data
corresponding to the source track ST is recorded, that is,
video data equivalent to the result obtained by applying the
effect track to the real data corresponding to the source
track ST is recorded, it is possible for an even playback
apparatus incapable of processing any effect to play back
the QT file. Thus, downward compatibility is perfectly
achieved.
In addition to such the alternate track that allows the
even playback apparatus incapable of processing any effect
to play back the QT file, the video disk apparatus 1 also
produces an alternate track in a form in which the effect
type is replaced by another effect type, and sets the
priority to each of the plurality of alternate tracks. This
makes it possible to provide, to a user, a result of the
effect according to the alternate track in which the effect
type is changed to another effect type in preference to the
alternate track that causes a reduction in picture quality
to occur when an extra encoding/decoding process is
performed.
In the present embodiment, priorities for the effect
track and alternate tracks are determined in accordance with
required processing power, and thus the second alternate
track in which the result obtained by processing the video
data according to the effect track is recorded is assigned
the lowest priority. Thus, the alternate track having the
risk of degradation in picture quality due to the repetition
of the process including the data compression and
decompression is assigned the lowest priority thereby
minimize the probability that degradation in picture quality
occurs.
(3) Advantages of Embodiment
According to the present embodiment of the invention,
as described above, at least an alternate track including
video data equivalent to video data obtained by performing a
process according to an effect track is formed, and the
processing priority level for the alternate track is defined
thereby making it possible to provide to a user the result
of the effect process using the alternate track including
the video data even when an apparatus used to play back the
video data does not have the capability of processing the
effect. Thus, it is possible to provide to a user the
result of the effect process regardless of a difference in
processing capability among apparatus.
By providing an alternate track including an effect
which is an alternative of the effect described in the
effect track, in addition to the alternate track including
the video data, it becomes possible for an apparatus or a
system having the capability of processing the alternative
effect to provide to users the result of application of the
alternative effect to the video data, which is higher in
picture quality than the result given based on the alternate
track including the video data.
By describing the priority of the alternate track in
the block of the user data of the QT file, it becomes
possible to provide the result of application of the effect
to users regardless of a difference in processing capability
among apparatus used.
In the playback operation, a processable alternate
track is detected based on the priority level, the QT file
is played back using the detected alternate track. Thus, it
is possible to provide the result of application of the
effect to users regardless of a difference in processing
capability among apparatus used.
(4) Embodiment 2
Fig. 31 is a diagram comparative to Fig. 29 and showing
an alternate track created by an video disk apparatus
according to an second embodiment of the present invention.
In this embodiment, a track produced as a result of applying
an effect to video data according to an effect track ET is
recorded as an alternate track AT. In this alternate track
AT, real data of video data is recorded only in the period
in which the effect described in the effect track ET can
cause a change to occur in the video data. Furthermore, in
this period, real data of video data is recorded only for
mosaic (MOSA) which is highly likely to be difficult to
process for the conventional QT player. Thus, in the
present embodiment, it is possible to achieve downward
compatibility using a less file size than is needed in the
first embodiment.
Accordingly, the flag is set to 1 for all of the source
track ST, the effect track ET, and the alternate track AT,
and only the effect track ET is set to belong to the
alternate group. The priority is set such that higher
priority is given in the order the source track ST, the
effect track ET, and the alternate track AT. The layer is
set such that a higher level is assigned in the order the
alternate track AT, the effect track ET, and the source
track ST.
When a QT file in which tracks are recorded in the
above-described manner is played back, the effect track or
the alternate track is processed in accordance with the
setting of the flag. In this playback operation, when it is
difficult to process the effect track, the result of
applying the effect is provided to a user by using the
alternate track.
That is, for the QT file recorded using the present
video disk apparatus, as represented by a reference symbol
FBI, the video data read from the source track ST is
processed in accordance with the effect track ET, and the
result is presented to a user.
Note that the flag is set to 1 for all the source track
ST, the effect track ET, and the alternate track AT.
Therefore, for example, when it is difficult for the present
video disk apparatus to process the mosaic effect, the
source track ST, the effect track ET, and the alternate
track AT are all processed concurrently. As a result, as
represented by reference symbol PB2, the playback process is
performed in accordance with the effect track immediately
before the mosaic process and the result of the processing
according to the effect track is presented to a user. In
the mosaic period, because a smaller layer value is assigned
to the alternate track than the layer value assigned to the
effect track, the result of playback according to the
alternate track is presented to the user. After this period,
there is no video data corresponding to the alternate track
AT, and thus the result of the process according to the
original effect track is presented to the user.
On the other hand, when the QT file is processed by a
computer, the computer cannot interpret the priority set in
the priority field, and thus the playback operation is
performed only in accordance with the setting of the flag
and the alternate group. As a result, the result of the
process performed in a similar manner as described above
with reference to symbol PB2 is presented to the user. In
this case, if the apparatus or the system used to playback
the QT file does not have the capability of processing
effects, it is impossible to present the result of the
effect process to the user.
In the present embodiment, because real data of video
data is assigned only to a period in which the video data is
changed according to the effect track, similar advantages to
those obtained in the first embodiment can be achieved using
a less file size.
(5) Embodiment 3
Fig. 32 is a diagram comparative to Fig. 29 and showing
an alternate track created by an video disk apparatus
according to an third embodiment of the present invention.
In this embodiment, a track of video data obtained as a
result of applying an effect described in an effect track ET
on video data of an original source track ST1 is formed as a
second source track ST2, and a second effect track
indicating an effect to be applied to this source track is
formed as an alternate track.
For example, in the present embodiment, when there is
an effect track including a mosaic (MOSA) effect, a null
effect, and a color tint effect to be sequentially applied
to video data read according to the first source track ST1,
a first alternate track ATI is formed by replacing the
mosaic (MOSA) effect with a blur effect. Furthermore, a
source track ST2 is formed so as to include video data
obtained as a result of applying the above sequence of
effects including the mosaic (MOSA) effect, the null effect,
and the color tint effect to the original video data. In
the null effect period, no video data is assigned to the
source track ST2. This allows a reduction in the file size
of the QT file.
An second alternate track AT2 is then formed which
first causes a null effect process to be performed on the
video data of the source track ST2 subjected to the mosaic
(MOSA) effect process, and then causes a sequence of effects
including a null effect and a color tint effect to be
performed on video data read according to the original
source track ST1. Furthermore, a third alternate track AT3
is formed which first causes a null effect process to be
performed on the video data of the source track ST2
subjected to the mosaic (MOSA) effect process, then causes a
null effect process to be performed on the video data of the
original source track ST1, and finally causes a null effect
process to be performed on the video data of the source
track ST2 subjected to the color tint process.
The flag is set to a value of 1 for the first and
second source tracks ST1 and ST2 and the effect track ET,
and to a value of 0 for the other tracks. The alternate
group is set to a value of 1 for the effect track ET and the
first to third alternate tracks ATI to AT3. The layer is
set to a default value of 0 for the original source track
ST1, a value of -1 for the effect track ET and the first to
third alternate tracks ATI to ATS so that these tracks are
displayed in a layer upper the layer of the source track ST1,
and a value of 1 for the second source track ST2 so that
this track is displayed in a layer lower than the layer of
the original source track ST1.
The priority levels are set such that the highest
priority level is assigned to the first source track ST1 and
the priority level decreases in the order the first source
track ST1, the second source track ST2, the effect track ET,
the first alternate track ATI, the second alternate track
AT2, and the third alternate track ATS.
That is, the processing priority levels for the effect
track ET and the first to third alternate tracks ATI to AT3
are set in the order in which the required processing power
decreases from the highest to the lowest. On the other hand,
the same displaying priority is assigned to the effect track
ET and the first to third alternate tracks ATI to ATS.
The playback process can be performed in a similar
manner to the process shown in Fig. 30. That is, an
processable effect track or alternative track is detected by
sequentially checking the tracks in the order of the
processing priority, and the source track ST1 or ST2 is
processed in accordance with the detected processable track.
Thus, when the QT file recorded using the video disk
apparatus according to the present embodiment, the result of
playback of the first source track ST is processed according
to the effect track ET, and the result is presented to a
user. On the other hand, when this QT file is played back
using a video disk apparatus incapable of processing the
mosaic effect although capable of processing the other
effects, the result of playback according to the first
source track ST1 is processed according to the first
alternate track ATI, and the result is presented to the user,
In these cases, although video data of the second source
track ST2 is played back, the result of the playback is not
presented to the user because of the setting in terms of the
layer.
In the case in which the video disk apparatus used is
also incapable of processing the blur effect set in the
first alternate track ATI, the second alternate track AT2 is
selected. In this case, the video data of the second source
track ST2 subjected to the mosaic process is first subjected
to the null effect process, thereafter the video data of the
first source track ST1 is subjected to the sequence of
effects including the null effect and the color tint effect,
and the result is presented to the user. When the video
disk apparatus is incapable of processing even the color
tint effect process set in the second alternate track AT2,
the third alternate track AT3 is selected. In this case,
the video data of the second source track ST2 subjected to
the mosaic process is first subjected to the null effect
process, thereafter the video data of the first source track
ST1 is subjected to the null effect process, and finally the
video data of the second source track subjected to the color
tint process is subjected to the null effect process, and
the result is presented to the user.
On the other hand, when the QT file is played back
using a QT player running on a computer, if the QT player is
incapable of processing the mosaic effect, one of the first
to third alternate tracks ATI to AT3 is selected, and the
result of the process according o the selected alternate
track is presented to a user. In this case, it is possible
to upgrade the QT player to a version capable of handling
the mosaic effect.
In the present embodiment, as described above, an extra
source track is formed which includes video data obtained as
a result of performing an effect process on original video
data according to an effect track, and an alternate track is
formed which includes management information of an effect to
be applied to the extra source track thereby achieving
advantages similar to those achieved in the previous
embodiments.
(6) Other Embodiments
In the embodiments described above, by way of example,
the present invention is applied to specific effects such as
the mosaic effect and the blur effect. The effects are not
limited to those, but the present invention may also be
applied to other effects.
In the embodiments described above, by way of example,
the present invention is applied to a video disk apparatus
designed to record/play back a QT file. The video disk
apparatus is not limited to that of such a type, but the
present invention may be applied to a wide variety of
recording/playback apparatus designed to record/play back
files in other formats such as ISOBase Media file format
(MPEG4-partl2) based on the QT format, Motion JPEG2000 (MJ2)
file format, AVC (Advanced Video Coding (MPEG4-partlO)) file
format, etc.
In the embodiments described above, by way of example,
a QT file is recorded on an optical disk by using a video
disk apparatus according to the present invention. However,
the recording medium is not limited to the optical disk.
The present invention may also be applied to other recording
media such as a magnetic disk, a memory cord, etc.
In the embodiments described above, by way of example,
the present invention is applied to a video disk apparatus.
Note that the present invention may also be applied to a
wide variety of apparatus such as a portable telephone or a
PDA (Personal Digital Assistants) device capable of taking a
movie, a server capable of recording video data received via
a wireless/wired communication channel, various recording
apparatus capable of recording video data, a personal
computer capable of editing a video data file obtained as a
result of taking a movie, etc.
Industrial Applicability
The present invention can be used when a video data
file in the QT format obtained as a result of taking a movie
is edited or the edited QT file is played back.

CLAIMS
1. A file recording apparatus for editing video data
in accordance with a command input by a user and recording
the resultant edited video data in the form of a file,
the file including
a block of real data management information which is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described and an effect track in which management information associated with an effect to be applied to the video data is described, and
a block of real data including at least real data associated with the effect track,
the file recording apparatus forming, in the block of management information, at least
an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and
information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track.
2. The file recording apparatus according to Claim 1,
wherein an alternate track for an alternative use of the
effect track is formed in the block of management

information, the alternate track including an effect which is an alternative to the effect described in the effect track.
3. The file recording apparatus according to Claim 2,
wherein the information indicating the priority level is
described in a block of user data of the alternate track
including the video data and also in a block of user data of
the alternate track for alternative use of the effect track.
4. The file recording apparatus according to Claim 3,
wherein in the block of the user data, property information
associated with the corresponding track is described.
5. The file recording apparatus according to Claim 1,
wherein the alternate track including the video data is
formed such that real data of the video that is assigned
only in a period in which a change occurs in the video data
when the effect track is applied to the video data.
6. The file recording apparatus according to Claim 1,
wherein the alternate track including the video data is a
track of management information associated with an effect to
be applied to another source track including video data
obtained as a result of applying the effect track to the
original video data.
7. A file recording method including editing video
data in accordance with a command input by a user and
recording the resultant edited video data in the form of a
file,the file includinga block of real data management information which is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described and an effect track in which management information associated with an effect to be applied to the video data is described, and
a block of real data including at least real data associated with the effect track,
the file recording method including the step of forming, in the block of management information, at least
an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and
information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track.
8. A program for causing a computer to execute a file recording process including editing video data in accordance with a command input by a user and recording the resultant edited video data in the form of a file, the file including
a block of real data management information which

is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described and an effect track in which management information associated with an effect to be applied to the video data is described, and
a block of real data including at least real data associated with the effect track,
the program of the file recording process including the step of forming, in the block of management information, at least
an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and
information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track.
9. A storage medium in which a program for causing a computer to execute a file recording process is stored, the file recording process including editing video data in accordance with a command input by a user and recording the resultant edited video data in the form of a file, the file including
a block of real data management information which is organized in a hierarchical structure and which includes

at least a source track in which management information associated with the video data is described and an effect track in which management information associated with an effect to be applied to the video data is described, and
a block of real data including at least real data associated with the effect track;
the program of the file recording process including the step of forming, in the block of management information, at least
forming at least an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and
information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track.
10. A file playback apparatus adapted to play back video data recorded in the form of a file on a recording medium and output the resultant video data, the file including
a block of real data management information which is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described, an effect track in which management information associated with an effect to

be applied to the video data is described, and an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track, and
a block of real data including at least real data associated with the effect track,
the file playback apparatus performing a process including the step of
detecting a processable alternate track in the order from the highest priority level to lower priority levels based on the information indicating the priority level and playing back the file using the detected alternate track.
11. A file playback method of playing back video data recorded in the form of a file on a recording medium and outputting the resultant video data,
the file including
a block of real data management information which is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described, an effect track in which management information associated with an effect to
be applied to the video data is described, and an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track, and
a block of real data including at least real data associated with the effect track,
the file playback method including the step of
detecting a processable alternate track in the order from the highest priority level to lower priority levels based on the information indicating the priority level and playing back the file using the detected alternate track.
12. A program for causing a computer to execute a file playback process including playing back video data recorded in the form of a file on a recording medium and outputting the resultant video data,
the file including
a block of real data management information which is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described, an effect track in which management information associated with an effect to be applied to the video data is described, and an alternate

track including video data equivalent to video data obtained by performing a process according to the effect track, and information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track, and
a block of real data including at least real data associated with the effect track,
the program of the file playback process including the step of
detecting a processable alternate track in the order from the highest priority level to lower priority levels based on the information indicating the priority level and playing back the file using the detected alternate track.
13. A storage medium in which a program for causing a computer to execute a file playback process is stored, the file playback process including playing back video data recorded in the form of a file on a recording medium and outputting the resultant video data,
the file including
a block of real data management information which
is organized in a hierarchical structure and which includes at least a source track in which management information associated with the video data is described, an effect track

in which management information associated with an effect to be applied to the video data is described, and an alternate track including video data equivalent to video data obtained by performing a process according to the effect track, and information indicating the processing priority level assigned to the alternate track of the video data with respect to the processing priority level assigned to another track, and
a block of real data including at least real data associated with the effect track,
the program of the file playback process including the step of
detecting a processable alternate track in the order from the highest priority level to lower priority levels based on the information indicating the priority level and playing back the file using the detected alternate track.