JPH11203794A - Information recording disk, reproducer and reproducing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information recording disk enabling variations so as not to be generated in waiting times (start-up periods) which are to be generated at the time of starting the reproducing of a system stream even with respect to plural reproducers whose performance of data processing speeds or the like are different and its reproducer and the reproducing method of the disk. SOLUTION: An information recording disk stores at least one system stream 310, which includes silent cells 312 defining a silent period and audio cells 314 defining voice data to be reproduced after the silent period. The silent period is a period during which a silent state is kept until the reproducing of the audio cells 314 is started after the system stream 310 to be reproduced in among at least one system stream 310 stored in the information recording disk is decided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording disk for storing a system stream, a reproducing apparatus and a reproducing method thereof. In particular, the present invention relates to an information recording disk, a reproducing apparatus, and a reproducing apparatus for enabling a plurality of reproducing apparatuses having different performances such as data processing speeds to have a constant waiting time generated at the start of reproduction of a system stream. About the method.

[0002]

2. Description of the Related Art Conventionally, an optical disk for storing and reproducing audio information or moving image information is a CD (Compact).
Disk and LD (Laser Disk) are known.

A CD is an optical disk having a diameter of 12 cm. The CD stores digital data obtained by encoding music information using an encoding technique called linear PCM. CDs have been used as storage media for music applications.

[0004] The LD is an optical disk having a diameter of 30 cm. The LD stores moving picture information with sound in the form of an analog signal. LDs have been used as storage media for video applications such as movies.

Recently, a new type of optical disk has begun to appear. Such optical discs include
For example, there is an optical disc having a diameter of about 12 cm, which achieves long-time recording or sufficiently high quality by efficiently compressing one or both of music information and moving picture information including sound. Furthermore, optical disks having a file structure that facilitates data exchange with computers and communications have begun to appear.

[0006] Under such circumstances, it is required to record and reproduce audio data of higher quality than a CD. As an optical disc capable of recording and reproducing audio data of higher quality than a CD, a DVD-
Optical discs conforming to the Video standard have been developed and realized. This optical disk is a linear PCM, 96k
It enables recording and reproduction of high-quality audio data of 24 Hz sampling. However, DV
With the D-Video standard, it was impossible to reproduce high-quality linear PCM multi-surround sound and higher-quality audio information.

[0007]

Since high-quality audio data has a large data amount, a high-speed audio data transfer rate is required when reproducing high-quality audio data.

The inventor of the present invention has found through various years of research and development of an optical disk storing high-quality audio data that the waiting time that occurs when reproduction of high-quality audio data starts causes various problems.

At the time of starting reproduction of an optical disk, the waiting time from the determination of a system stream to be reproduced among one or more system streams stored on the optical disk to the start of reproduction of the determined system stream is started. Will be needed. This waiting time is called the startup period. When there are a plurality of playback devices having different performances such as data processing speeds, the startup periods of the playback devices usually differ from each other.

[0010] The start-up period, taking a high quality audio data having a stream structure of MPEG standard as an example, include a period T _s and the period T _c and time period T _m. Here, the period T _s is a period for the reproducing apparatus to seek to a position on the optical disk where the audio data is stored. The period _Tc is a period from when the audio data is input to the decoder to when the first correctly decoded audio data is output from the decoder. In the period _Tc , PTS (Presentat) included in the system stream is used.
A period for adjusting the output timing of the system stream by referring to the “ion time stamp” and a period for verifying that the audio data included in the system stream is correct are included. Period T
_m is a period for transitioning the muting circuit of the analog output unit from the muting state to the non-muting state.

When the system decoder and the audio decoder are housed in separate housings, or
If the system decoder and the audio decoder are mounted on different LSIs, respectively, the start-up period becomes longer. In these cases, the adjustment of the output timing based on the PTS and the verification that the audio data is correct must be performed independently.

When the start-up period is lengthened, the output timing of the system stream at the time of starting the reproduction in a specific reproducing apparatus may be out of order, which may cause a malfunction such that the head audio data of the system stream is not reproduced.

[0013] In addition, since the start-up period varies among a plurality of reproducing apparatuses, when a plurality of music pieces are continuously reproduced, the time between the music pieces is different even if the discs have the same time. The time between them cannot be set uniquely, which is disadvantageous for the disc creator and the viewer.

[0014] The present invention has been made in view of the above-described problems, and a waiting time (start-up period) generated at the start of reproduction of a system stream even for a plurality of reproduction apparatuses having different performances such as data processing speeds. )
It is an object of the present invention to provide an information recording disk, a reproducing apparatus and a reproducing method thereof, which make it possible to prevent variations in the information.

[0015]

An information recording disk according to the present invention is an information recording disk for storing at least one system stream, wherein the system stream includes a silent cell defining a silent period and a silent cell defining the silent period. Audio cells defining audio data to be reproduced later, wherein the silent period is determined after a system stream to be reproduced is determined from at least one system stream stored in the information recording disc. This is a period in which silence is required until reproduction of the audio cell included in the system stream thus started is started, thereby achieving the above object.

[0016] The silent period is a period from when a system stream to be reproduced among the at least one system stream stored in the information recording disc is determined to when reproduction of the determined system stream is started. A period required by the playback device may be included.

[0017] The information recording disk further stores information indicating a reproduction order of a plurality of system streams, and the silent period is one of the plurality of system streams.
There may be a period in which silence is required from the end of one reproduction to the start of reproduction of audio cells included in the next system stream.

[0018] Each of the silent cell and the audio cell may include audio data encoded in the same encoding mode, and an output level of the audio data included in the silent cell may be substantially zero. .

The system stream is provided with a time stamp defining an output timing at a predetermined interval, and the presentation period of the audio cell includes a first time stamp and a last time stamp added to the audio cell. And the silent period may be determined based on a difference between a first time stamp and a last time stamp given to the silent cell. The reproducing apparatus of the present invention is a reproducing apparatus for reproducing an information recording disk, wherein the information recording disk stores at least one system stream, the system stream includes a silent cell defining a silent period, and the silent section. An audio cell defining audio data to be reproduced after a period, wherein the silent period is determined after a system stream to be reproduced among at least one system stream stored in the information recording disc is determined. A period during which the audio cells included in the determined system stream are to be silenced before the reproduction of the audio cells is started, and the reproducing apparatus reproduces the audio cell from at least one system stream stored in the information recording disk. A read section for reading the system stream to be From the middle of the silent cell included in the read system stream, and a reproduction section for reproducing a part and the audio cell of the silent cell, thereby the objective described above being achieved.

The silence period is a period from when a system stream to be reproduced among the at least one system stream stored on the information recording disc is determined to when reproduction of the determined system stream is started. A period required by the playback device may be included.

[0021] The information recording disk further stores information indicating a reproduction order of the plurality of system streams, and the silence period includes one of the plurality of system streams.
There may be a period in which silence is required from the end of one reproduction to the start of reproduction of audio cells included in the next system stream.

Each of the silent cell and the audio cell may include audio data encoded in the same encoding mode, and an output level of the audio data included in the silent cell may be substantially zero. .

The system stream is provided with a time stamp defining an output timing at a predetermined interval, and the presentation period of the audio cell includes a first time stamp and a last time stamp added to the audio cell. And the silent period may be determined based on a difference between a first time stamp and a last time stamp given to the silent cell.

A reproducing method according to the present invention is a reproducing method for reproducing an information recording disk, wherein the information recording disk comprises:
Storing at least one system stream, the system stream including a silent cell defining a silence period and an audio cell defining audio data to be reproduced after the silence period, wherein the silence period includes the information A period during which silence is required from when a system stream to be reproduced is determined out of at least one system stream stored on the recording disk to when reproduction of the audio cell included in the determined system stream is started. Reading the system stream to be reproduced from at least one system stream stored in the information recording disc; and reading the system stream from the middle of the silent cell included in the read system stream. , The silent cell It includes a step of playing a part and the audio cell, thereby the objective described above being achieved.

[0025] The silent period is a period from when a system stream to be reproduced among the at least one system stream stored in the information recording disc is determined to when reproduction of the determined system stream is started. A period required by the playback device may be included.

[0026] The information recording disk further stores information indicating a reproduction order of a plurality of system streams, and the silent period includes one of the plurality of system streams.
There may be a period in which silence is required from the end of one reproduction to the start of reproduction of audio cells included in the next system stream.

[0027] Each of the silent cell and the audio cell may include audio data encoded in the same encoding mode, and the output level of the audio data included in the silent cell may be substantially zero. .

The system stream is provided with a time stamp defining an output timing at a predetermined interval, and the presentation period of the audio cell includes a first time stamp and a last time stamp added to the audio cell. And the silent period may be determined based on a difference between a first time stamp and a last time stamp given to the silent cell.

[0029]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 shows a data structure of a system stream 210 conforming to MPEG. The optical disc contains at least one system stream 2
10 may be stored.

[0031] The system stream 210 can include a plurality of elementary streams. The elementary streams are classified into a video elementary stream that stores moving image information and an audio elementary stream that stores audio information. Each of the plurality of elementary streams is divided into a plurality of packs. Each of the plurality of packs has a length of 2 Kbytes.

In the example shown in FIG. 1, the system stream 210 is composed of one audio elementary stream. The system stream 210 includes a plurality of audio packs 220. The voice pack 220 includes the symbol A1
ＡA14.

The audio pack 220 includes a pack header 222
, Packet header 224 and data field 226
And

The pack header 222 includes a pack start code and an SCR (System Clock Reference).
MPEG-compliant data such as R.n. (rence) and MUX (Multiplex) rate.

The packet header 224 includes a stream I
D, packet length, STD (SystemTargetD
encoder) buffer scale size, PTS (Pr
It describes MPEG-compliant data such as an Esentation Time Stamp. Note that MP
According to the EG standard, the packet header 224 includes a DTS (Decoding) that defines the data decoding timing.
Although an area for storing “Time Stamp” is reserved, this area is not usually used in the audio elementary stream.

The stream ID described in the packet header 224 is a code indicating the type of data stored in the data field 226. For example, if the data stored in the data field 226 is audio data, the code “10111101” is the stream ID
In the packet header 224.

A substream ID is stored in the first 8 bits of the data field 226. The upper 5 bits of the 8 bits of the substream ID indicate the encoding type. The encoding type is LPCM, AC
3, DTS, etc. The lower 3 bits of the 8 bits of the substream ID indicate the identification number of the substream.
The identification number is one of 0-7. A system stream can have up to eight audio elementary streams. Up to eight audio elementary streams can be identified using the identification numbers.

The SCR in the pack header 222 and the PTS in the packet header 224 are used to adjust synchronization between the audio pack decoding process and the sub-picture pack decoding process.

FIG. 2A shows a system stream 210 including a plurality of audio packs A1 to A6 and audio packs A1 to A6.
Shows the relationship between SCR and PTS assigned to each of the.

When the reproducing apparatus reproduces the system stream 210 stored on the optical disk, the reproducing apparatus uses the SCR included in the first audio pack A1 of the system stream 210 as an STC (System) which is a reference clock.
Time Clock) is set as the initial value and ST
Audio pack A2 following audio pack A1 while referring to C
To A6 are input to the decoder at the timing indicated by the SCR. The decoder decodes the input audio pack. The decoded audio pack is output from the decoder to the outside at the timing indicated by the PTS.

The present inventor has analyzed problems that may occur when high-quality audio data is reproduced using the data structure of the system stream shown in FIG. 1 and the reproducing method shown in FIG. 2A. The results of the analysis are described below.

The inventor has noticed that attention should be paid to the timing for initializing the STC (that is, the timing for resetting the STC). As described above, FIG.
In the reproduction method indicated by A, the STC is reset when the first audio pack A1 included in the system stream 210 is reproduced. However, before the reproduction of the first audio pack A1 is started, a waiting time for preparing the reproduction is required. Since the length of the waiting time varies depending on the processing capability of the reproducing apparatus, the time at which the first audio pack A1 is reproduced varies depending on the type of the reproducing apparatus. As a result, depending on the type of playback device, S
There may be a problem that the time at which the TC is reset varies.

This will be described in more detail.

When the reproduction of the optical disk is started, the waiting time from the determination of the system stream to be reproduced among the one or more system streams stored in the optical disk to the start of reproduction of the determined system stream is started. Will be needed. This waiting time varies depending on the capacity of the playback apparatus, and generally tends to be short for high-end machines and long for popular machines. This waiting time is called the startup period.

[0045] The start-up period, taking a high quality audio data having a stream structure of MPEG standard as an example, include a period T _s and the period T _c and time period T _m. Here, the period T _s is a period for the reproducing apparatus to seek to a position on the optical disk where the audio data is stored. The period _Tc is a period from the input of the audio data to the decoder to the output of the decoded audio data from the decoder. The period _Tc includes a period for adjusting the output timing of the system stream by referring to the PTS included in the system stream and a period for verifying that the audio data included in the system stream is correct. . Since the verification of the audio data is usually performed before outputting the audio data according to the PTS, the period _Tc is equal to the period obtained by subtracting the SCR from the PTS. The period _Tm is a period for transitioning the muting circuit of the analog output unit from the muting state to the non-muting state.

When there are a plurality of playback devices having different performances such as data processing speed, the start-up periods of the playback devices are different from each other. This depends on the type of playback device, the period T _s ,
Period T _c and time period T _m is because changes respectively.

For example, in a commercially available reproducing apparatus, the period T _s (seek period) is several tens of msec to about 5
It is about 00 msec. However, the period T _s is dependent like motor torque for disk rotation to be mounted to the playback apparatus, the period T _s is also present reproducing apparatus of the order up to several seconds. That is, the period T _s will vary on the order of a few 100msec depending on the type of reproduction apparatus.

The period _Tc depends on what algorithm the reproducing apparatus employs as an algorithm for decoding. The period _Tc will vary on the order of several hundred msec depending on the type of algorithm employed.

The period T _m also changes on the order of several hundred msec depending on the performance of the circuit mounted on the reproducing apparatus.

FIG. 2B shows a case where the system stream 210 having the same data structure is reproduced by using two different types of reproduction apparatuses (reproduction apparatuses # 1 and # 2). This shows the timing of starting.

The playback device # 1 has lower performance than the playback device # 2. When reproducing the system stream 210 using the reproducing apparatus # 1, the reproducing apparatus # 2
The start-up period is longer than in the case where the system stream 210 is reproduced by using. That is, startup period # 1> startup period # 2.

In the reproducing apparatus # 1, the start-up period #
After elapse of 1, the STC is reset at time a2 based on the SCR of the first audio pack A1. as a result,
Reproduction of the system stream 210 starts at time a2. On the other hand, in the reproducing device # 2, after the start-up period # 2 has elapsed, the STC is reset at time a1 based on the SCR of the first audio pack A1. As a result, the reproduction of the system stream 210 starts at time a1.

As described above, according to the type of the reproducing apparatus,
The inventor has found that the reproduction start time of the system stream changes. In the example shown in FIG. 2B, at time a2 when the playback device # 1 starts playing the first audio pack A1 of the system stream 210, the playback device # 2 has already played the fifth audio pack A5 of the system stream 210. It can be seen that it corresponds to the start time.

Next, a data structure of a system stream and a method of reproducing the system stream according to the present invention will be described. The data structure of the system stream and the method of reproducing the system stream according to the present invention are suitable for reproducing high-quality audio data.

FIG. 3 shows the data structure of the system stream 310 stored on the optical disc according to the first embodiment of the present invention.

In the example shown in FIG. 3, the system stream 310 is composed of one audio elementary stream. The system stream 310 includes a silent cell 312 defining a silent period and an audio cell 314 defining audio data to be played after the silent period. Each of silent cell 312 and audio cell 314 includes a plurality of audio packs 320.

During the silence period, after the system stream 310 to be reproduced among the at least one system stream 310 stored on the optical disc is determined, the reproduction of the audio cell 314 included in the determined system stream 310 is started. It is defined as the period of silence before it is started. Further, when information indicating the reproduction order of a plurality of system streams is stored on the optical disc, the silent period is included in the next system stream after the reproduction of one of the plurality of system streams ends. It is defined as a period in which silence must be reached before the reproduction of the audio cell is started.

In the example shown in FIG.
12 includes audio packs S1 to S8, and audio cells 3
14 includes audio packs A1 to A14. Voice Pack S1
To S8 and audio packs A1 to A1
4 is the same as the data structure of the audio pack 220 shown in FIG. The silent cell 312
May include N audio packs, and audio cell 314 may include M audio packs. Here, N and M are 1 or more arbitrary integers.

The audio data included in the audio packs S1 to S8 and the audio data included in the audio packs A1 to A14 are encoded in the same encoding mode. MPEG
This is because the silent cell 312 and the audio cell 314 are one stream.
Here, the same encoding mode means that encoding attributes such as an encoding type (for example, LPCM and AC3) and a sampling rate are all the same.

The output level of the audio data contained in the audio packs S1 to S8 is substantially zero. That is, in the silent cell 312, audio data that is almost silent when audio data is output is stored. However, it is not essential that the output level of the audio data stored in the silent cell 312 is substantially 0 in defining a silent period. This is because, as will be described later, even when the audio data stored in the silent cell 312 is not substantially 0, silence can be achieved in a silence period by controlling the muting circuit.

The audio packs A1 to A1 of the audio cell 314
The PTS included in each of A14 defines the timing at which the decoded audio pack is output from the decoder. Accordingly, the difference between the PTS included in the first audio pack A1 of the audio cell 314 and the PTS included in the last audio pack A14 of the audio cell 314 is determined by the presentation period (presence) of the audio cell 314.
ntation period). Thus, the presentation period of the audio cell 314 is the first PTS assigned to the audio cell 314.
And the last PTS.

On the other hand, the PTS included in each of the audio packs S1 to S8 of the silent cell 312 also defines the timing at which the decoded audio pack is output from the decoder. These PTSs are
Rather than defining the presentation period of No. 2, a silence period when starting reproduction of the system stream 310 including the silent cell 312 is defined. That is, the PTS included in the first audio pack S1 of the silent cell 312 and the audio cell 3 next to the silent cell 312 are included.
The difference from the PTS included in the first 14 audio packs A1 corresponds to the silence period of the system stream 310.
Thus, the silence period of the system stream 310 is
It is determined based on the difference between the first PTS given to the silent cell 312 and the first PTS of the audio cell 314 following the silent cell 312.

The silence period of the system stream 310 defined by the silent cell 312 is used by the playback device as a period for absorbing a startup period that varies depending on the type of the playback device. The length of the silent period is predetermined so that the silent period includes the start-up period. In a preferred embodiment, the length of the silence period is predetermined to include the longest start-up period of a playback device that can be manufactured according to the MPEG standard.

When a reproducing apparatus is provided, a start-up period of the reproducing apparatus can be calculated in advance. For example, seek period T _s can be calculated from the seek distance. Both the period _Tc and the period _Tm are fixed values in the reproducing apparatus. Thus, start-up period of the reproduction apparatus can be calculated as the sum of the seek period T _s and the period T _c and time period T _m.

FIG. 4A shows a plurality of audio packs S1 to S8,
The relationship between the system stream 310 including A1 to A14 and the SCR and PTS assigned to each of the audio packs S1 to S8 and A1 to A14 is shown.

When the reproducing apparatus reproduces the system stream 310 stored on the optical disk, the reproducing apparatus uses the SCR included in the first audio pack S1 of the silent cell 312 as an STC (System T) as a reference clock.
audio packs S2 to S2 that are set as initial values of the
8. A1 to A14 are input to the decoder at the timing indicated by the SCR. The decoder decodes the input audio pack. The decoded audio pack is P
It is output from the decoder to the outside at the timing indicated by TS.

FIG. 4B shows a case where the system stream 310 having the same data structure is reproduced by using two different types of reproduction apparatuses (reproduction apparatuses # 1 and # 2). This shows the timing of starting.

The playback device # 1 has lower performance than the playback device # 2. When playing back the system stream 310 using the playback device # 1, the playback device # 2
As compared with the case of reproducing the system stream 310 with a period T _s can take longer. That is, period T _s # 1>
Period T _s # 2.

In the reproducing apparatus # 1, the reproducing apparatus # 1 is controlled so that the reproduction of the system stream 310 is started at time t2 after the elapse of the period T _s # 1. As shown in FIG. 4A, the first audio pack having an SCR larger than time t2 is audio pack S6. Therefore, the SCR of the sixth audio pack S6 of the silent cell 312
The STC is reset based on. As a result, the decoding of the audio data is started in the middle of the silent cell 312, and the audio can be output after the elapse of the period _Tc # 1.

However, even if the audio data is decoded,
No sound is output before time t3. This is because in the reproducing device # 1, the muting circuit is in a muting state before the time t3. The period T _m # 1 starts at time t3. In the period T _m # 1, the muting circuit is controlled to transition from the muting state to the non-muting state. At time k at which the period T _m # 1 ends, the muting circuit is in a non-muting state. Therefore, the audio data of the audio packs A1 to A14 reproduced from time k is output.

On the other hand, in the reproducing apparatus # 2, the reproducing apparatus # 2 is controlled so that the reproduction of the system stream 310 is started from the time t1 after the elapse of the period T _s # 2. FIG. 4A
As shown in the figure, the first audio pack having an SCR larger than the time t1 is the audio pack S3. Therefore, the STC is reset based on the SCR of the third audio pack S3 of the silent cell 312. as a result,
The decoding of the audio data is started in the middle of the silent cell 312, and the audio can be output after the elapse of the period _Tc # 2.

However, even if the audio data is decoded,
No sound is output before time t4. This is because in the reproducing device # 2, the muting circuit is in a muting state before the time t4. The period T _m # 2 starts from time t4. In the period T _m # 2, the muting circuit is controlled to transition from the muting state to the non-muting state. At time k at which the period T _m # 2 ends, the muting circuit is in the non-muting state. Therefore, the audio data of the audio packs A1 to A14 reproduced from time k is output.

As described above, in the reproducing apparatus # 1, reproduction is started from the audio pack S6 of the silent cell 312, and in the reproducing apparatus # 2, the audio pack S6 of the silent cell 312 is reproduced.
Reproduction is started from 3. However, in both the playback device # 1 and the playback device # 2, the output of sound is suppressed during the silent period. Thus, the silent period of the system stream 310 can always be the same regardless of the type of the playback device.

Note that even if the muting circuit malfunctions, in order to prevent the sound from being output during the silence period, the sound packs S1 to S1 of the silent cell 312 are required.
The output level of the audio data included in each of S8 may be set to substantially zero. Thus, during the period in which the silent cell 312 is being reproduced, the output of audio can be suppressed regardless of the operation of the muting circuit.

FIG. 5 shows a configuration of a reproducing apparatus 400 according to the first embodiment of the present invention.

The optical disk 410 stores at least one system stream 310 (FIG. 3).
The playback device 400 plays back at least one system stream 310 stored on the optical disc 410. The data structure of the system stream 310 is as shown in FIG.

Note that any information recording medium can be used as the optical disk 410. For example, the optical disk 41
0 may be a DVD.

The reproducing apparatus 400 reads out a system stream 310 to be reproduced from at least one system stream 310 stored on the optical disc 410, and reads the system stream 310 read out by the reading section 420 from the middle of the system stream 310. A playback unit 430 that plays back a part of the silent cell 312 and the audio cell 314 is included.

The reproduction section 430 is provided for the system stream 31
It includes a decoder 432 for decoding 0, an output unit 434 for outputting the decoded system stream 310, and a muting circuit 436 for determining whether to mute the output of the audio data.

The operations of the reading section 420 and the reproducing section 430 are controlled by the control section 438.

Hereinafter, the operation of the reproducing apparatus 400 will be described with reference to FIG. Since the reproducing apparatus 400 seeks to the position on the optical disk 410 where the audio data is stored, the audio data is input to the decoder 432 during the period T _s , and the decoded audio data is input to the decoder 432.
Period T _m of a for a period T _c and muting circuit 436 until the output transition from muting state to the non-mute state from is assumed both are previously calculated. The silent cell 3 of the system stream 310 stored on the optical disc 410
By 12, it is assumed that the silent period is defined to include a period T _s and the period T _c and time period T _m. As mentioned above, it is possible to make such an assumption.

The reading section 420 responds to an instruction from the control section 438 to read at least one of the
The system stream 310 to be reproduced is read from the three system streams 310. The system stream 310 to be played is, for example, selected by the user. Such a selection is made, for example, by selecting a desired item from a menu displayed on a television (not shown) connected to the playback device 400. Alternatively, the system stream 310 to be played may be automatically determined by the playback device 400. Such an automatic determination can be made by a program executed by the control unit 438 of the playback device 400.

[0083] The control unit 438, by comparing the respective SCR and seek period T _s of the audio pack S1~S8 included in the silent cell 312 of the system stream 310 read by the reading unit 420, audio pack S1 of ～S8, it determines the beginning of the audio pack (e.g., audio pack A6) having an SCR of greater than the value indicating the end time of the seek period T _s. Control unit 43
8 resets the STC based on the SCR of the audio pack A6. As a result, the audio pack A6 in the middle of the silent cell 312 is input to the decoder 432.

The decoder 432 decodes the input audio pack. The audio pack decoded by the decoder 432 is output from the decoder 432 according to the output timing defined by the PTS of the audio pack. Time decoded audio pack is output generally equal to the time period T _s has elapsed period T _c from completion.

The output section 434 outputs the audio data included in the decoded audio pack.

The muting circuit 436 is connected to the output unit 43
4 to determine whether or not to mute the audio data output. Control unit 438, to the start time of the period the T _m controls the muting circuit 436 to mute the audio data output from the output unit 434,
During the period _Tm , the muting circuit 436 is set to transition from the muting state to the non-muting state.
Control.

In this way, the system stream 31
No sound can be output during the silent period of zero.

The silent period defined by the silent cell 312 is defined so as to absorb a start-up period inherent to the playback device. Therefore, the playback device 400
Similarly, when the system stream 310 is reproduced using a reproducing device other than the
No sound can be output during the silent period of zero.

(Embodiment 2) A multimedia recording medium according to Embodiment 2 of the present invention will be described. (1) Physical Structure of Optical Disk FIG. 6A shows a DVD 10 which is a multimedia optical disk.
FIG. 7 is a diagram showing the appearance of FIG. FIG. 6B is a cross-sectional view of the DVD 107 along the line AA ′ shown in FIG. 6A. FIG. 6C is an enlarged view of a portion B shown in FIG. 6B.

As shown in FIG. 6B, the DVD 107 has a first transparent substrate 108, an information layer 109, and an adhesive layer 11.
0, the second transparent substrate 111 and the printing layer 112 for label printing are laminated in this order.

The first transparent substrate 108 and the second transparent substrate 111 are reinforcing substrates of the same material. In the example shown in FIG. 6B, the thickness of these substrates is about 0.6 mm. The thickness of these substrates is approximately 0.5 mm to 0.7 m
m is sufficient.

The adhesive layer 110 is provided between the information layer 109 and the second transparent substrate 111 to adhere the information layer 109 to the second transparent substrate 111.

On the surface of the information layer 109 which is in contact with the first transparent substrate 108, a reflection film (not shown) such as a metal thin film is formed. Concavo-convex pits are formed at a high density on this reflective film by a molding technique.

FIG. 6D shows the shape of the pit formed on the reflection film. In the example shown in FIG. 6D, the length of each pit is 0.4 μm to 2.054 μm. One track is spirally formed on the DVD 107. Each pit is formed along a spiral track so as to have an interval of 0.74 μm in the radial direction of the DVD 107. In this way, a pit row is formed on the spiral track.

When the DVD 107 is irradiated with the light beam 113, a light spot 114 is formed on the information layer 109 as shown in FIG. 6C. The information stored in the DVD 107 is detected as a change in the reflectance of the portion of the information layer 119 illuminated by the light spot 114.

The diameter of the light spot 114 on the DVD 107 is about 1 / 1.6 times the diameter of the light spot on a CD (Compact Disk). The numerical aperture NA of the DVD objective lens is larger than the numerical aperture NA of the CD objective lens, and the wavelength λ of the DVD light beam is CD
Is smaller than the wavelength λ of the light beam for use.

A DVD having such a physical structure can store about 4.7 Gbytes of information on one side.
The storage capacity of about 4.7 Gbytes is close to eight times the storage capacity of a conventional CD. Due to such large storage capacity of DVD,
It is possible to greatly improve the quality of moving images. It is also possible to greatly improve the reproduction time of a moving image. While the playback time of a conventional video CD is 74 minutes, the playback time of a DVD is 2 hours or more.

The basic technology for realizing such a large storage capacity is to reduce the spot diameter D of the light beam. The spot diameter D is given by a formula of spot diameter D = wavelength λ of laser / numerical aperture NA of the objective lens. Therefore, the spot diameter D can be narrowed down by reducing the wavelength λ of the laser and increasing the numerical aperture NA of the objective lens. Here, it should be noted that the numerical aperture NA of the objective lens is
Is large, coma aberration occurs due to the relative inclination (that is, tilt) between the disk surface and the optical axis of the light beam. In DVD, coma aberration is reduced by reducing the thickness of the transparent substrate. Reducing the thickness of the transparent substrate may cause another problem that the mechanical strength of the disk is reduced. In DVD, the strength of the transparent substrate is reinforced by bonding another substrate to the transparent substrate.
This overcomes the problem of the mechanical strength of the disk.

To read information stored on a DVD, a red semiconductor laser having a short wavelength of 650 nm and an objective lens having a large numerical aperture (NA) of about 0.6 mm are used. In addition to this, by using a thin transparent substrate of about 0.6 mm, about 4.7 G on one side of an optical disc having a diameter of 120 mm.
It became possible to store byte information.

FIG. 7A schematically shows a state in which a spiral track 20 is formed from the inner circumference to the outer circumference of the information layer 109 of the DVD 107. The spiral track 20 is divided into predetermined units called sectors. In FIG. 7A,
The sectors are indicated by symbols such as S1, S2,..., S99, and S100. Reading of information stored in the DVD 107 is performed in sector units.

FIG. 7B shows the internal structure of a sector. The sector includes a sector header area 21 and a user data area 22.
And an error correction code storage area 23.

The sector header area 21 stores a sector address for identifying a sector and its error detection code. The disk reproducing device determines from which sector of a plurality of sectors information should be read based on the sector address.

The user data area 22 contains 2 KB
Long data is stored.

The error correction code storage area 23 stores error correction codes for the sector header area 21 and the user data area 22 included in the same sector. When reading data from the user data area 22, the disk playback device performs error detection using the error correction code, and performs error correction according to the result of the error detection. This guarantees the reliability of data reading.

(2) Logical Structure of Optical Disk FIG. 8 shows a logical structure of the DVD 107 as an optical disk. As shown in FIG. 8, the area of the DVD 107 is divided into a lead-in area 31, a volume area 32, and a lead-out area 33. These areas can be identified by the identification information included in the sector address of the physical sector. Physical sectors are arranged in ascending order by sector address.

The lead-in area 31 stores data for stabilizing the operation of the disk reproducing apparatus at the start of reading.

In the lead-out area 33, no meaningful data is stored. The lead-out area 33 is used for notifying the disk playback device of the end of playback.

[0108] In the volume area 33, digital data corresponding to the application is stored. Physical sectors included in the volume area 32 are managed as logical blocks. A logical block is identified by assigning a continuous number (logical block number) to the physical sector following the physical sector No. 0, with the physical sector at the beginning of the volume area 32 being numbered zero.

As shown in FIG. 8, the volume area 3
2 is further divided into a volume / file management area 32a and an audio zone area 32c.

The volume / file management area 32a stores file system management information for managing a plurality of logical blocks as files in accordance with ISO13346. The file system management information is information indicating the correspondence between each file name of a plurality of files and the address of a logical block group occupied by each file. The disk reproducing device realizes accessing the optical disk in file units based on the file system management information. Specifically, the disc playback device refers to the file system management information,
The address of the logical block group corresponding to the given file name is obtained, and the logical block group is accessed based on this address. Thus, digital data of a desired file can be read.

The audio zone area 32c stores an audio manager 900 and one or more audio title sets 800.

The audio title set 800 includes a plurality of audio data and management information for managing the reproduction order. The audio title set 800 has a data structure for managing audio data in units called audio titles. Typically, an audio title corresponds to a music album that contains one or more songs.

(3) Data Structure of Audio Zone Area 32c The audio zone area 32c includes an audio manager 900 and one or more audio title sets 800.
Are stored.

(3.1) Audio title set 80
Data Structure of 0 FIG. 10 shows the data structure of the audio title set 800. The audio title set 800 includes a plurality of audio objects (hereinafter, referred to as AOBs) 802.
Audio title set information (ATSI) 801 for managing the reproduction order of a plurality of AOBs 802; and audio title set information backup (ATS)
I_BUP) 804. In the following description,
An audio title set may be abbreviated as ATS.

(3.1.1) Data Structure of AOB 802 The AOB 802 is packetized in 2 KB. The AOB 802 stores data in LPCM, AC3, MPEG audio, DTS or SDDS format (for MPEG audio, ISO / I
EC DIS 13818-3: July, 1996.
See For DTS, see DTS Coherent
Acoustics "Delivering hi
gh quality multichannel s
"ound to the consumer" Pre
sent at the 100th Conve
ntion 1996 May 11-14 Cope
See nhagen AES. For SDDS, S
DDS Specification for Dis
c (Version 1.0) -Digital au
dio multi-channel coding
Sony Corporation). In the case of LPCM, the sample bit is any one of 16, 20, and 24 bits, and the sampling frequency is 48 kHz, 9
6kHz, 192kHz, 44.1kHz, 88.2k
Hz or 176.4 kHz.

(3.1.2) Data Structure of Audio Title Set Information 801 The audio title set information 801 is composed of AOB 802
Contains information for managing the playback order. The reproduction order of the AOB 802 is specified by a program chain (PGC) as in the case of the video object (VOB). Different PGCs may define different playback orders of AOB 802.

As shown in FIG. 10, audio title set information (ATSI) 801 includes audio title set management table (ATSI_MAT) 811.
And PGC management information table (ATS_PGCIT) 8
12 is included.

Audio title set management table 8
11 is header information of the audio title set information 801. Audio title set management table 8
11, a pointer indicating the storage position of the AOB 802;
A pointer indicating a storage position of the PGC management information table 812 and attribute information of the AOB 802 are stored. When a still image is provided, attribute information of the still image is stored.

A PGC management information table (ATS_PGC)
The IT) 812 includes audio title set PGC information table information (ATS_PGCITI) 831, a plurality of audio title set PGC information search pointers (ATS_PGCI_SRPs) 832, and a plurality of PGs.
C information (ATS_PGCI) 833.

The audio title set PGC information search pointer (ATS_PGCI_SRPs) 831
This is an index of a plurality of program chain groups stored in the GC management information table 812, and specifies PGC information to be executed first for each title.

Each piece of PGC information describes the recording position of one or more audio objects on the disc and their reproduction order, and it is possible to describe the reproduction of the same audio object using different PGC information. PGC
Specifically, the information is “Audio title set PGC
General information (ATS_PGC_GI) "and" Audio title set program information table (ATS_P
GIT)] and “Audio title set cell playback information table (ATS_C_PBIT)”.

FIG. 12 shows the data structure of PGC information. As shown in FIG. 12, "audio title set PGC general information (ATS_PGC_GI)"
Is the number of programs, the number of cells included in the PGC information,
PGC playback time, "audio title set program information table (ATS_PGIT)" and "audio title set cell playback information table (ATS_C
_PBIT)] is recorded.

In the “audio title set program information table (ATS_PGIT)”, the AOB of each program and the program preceding it are described.
"Program physical allocation information" that indicates whether data is recorded at physically discontinuous locations on the disc,
Similarly, “program time attribute information” indicating whether the time represented by the time information with the previous AOB is continuous, “program start cell number” indicating the first cell number of the program, A "program still image flag" indicating whether or not a still image is included in the program, a "playback start audio cell time" indicating the first time information of the first audio cell included in the program,
"Total program playback time" indicating the program playback time
In addition, "speech pause time" indicating a silence time until the start of reproduction of a speech cell of a program is described.

[0124] The "audio title set cell reproduction information table (ATS_C_PBIT)" stores cell information constituting the AOB to be reproduced. In particular,
"Cell index number" indicating the order of the cells included in the program, "Cell type" indicating whether the attribute of the cell is a still image cell, a silent cell or a voice cell, and the audio title including the cell start address. AOB of the set
The "cell start address" described by the relative address from the first pack of "1" and the "cell end address" similarly described by the address of the last pack of the cell.

FIG. 11 shows an example of the configuration of an AOB. A
The OB is a part of the MPEG2 stream, and is a set of audio cells including a still image cell composed of a still image pack, a silence cell composed of an audio pack which is almost silent audio, and an audio pack of audio data constituting a music. is there. An AOB is composed of one or more audio cells, and may not include still image cells and silent cells. The still image cell and the silent cell are not continuous, and a silent cell or a voice cell always follows the still image cell. A voice cell always follows a silent cell. In FIG. 11, when a voice cell and a silent cell exist and are physically continuous and the time information is also continuous, that is, “program physical allocation information” is a value indicating “continuous” and “program time attribute information ] Also indicates the case of “continuous”.

In the drawing of the structure of the AOB shown in FIG. 11, a change in the value of the time information (PTS) of the AOB is shown on the upper side of the drawing. Here, point A is the value of the PTS of the first still picture cell. Point B indicates the first PTS of the silent cell. Point C indicates the first PTS of the voice cell. Thus, the PTS of the silence cell is continuous with the PTS of the voice cell,
There is no gap between the silent cell and the voice cell where data underflow occurs in the MPEG2 stream. B
Like the dot, the PTS of the silence cell is
When S is large, it indicates that the still image of the still image cell is displayed before the start of the reproduction of the silent cell. Similarly, the PTS of the next still picture cell is indicated by point D, and the PTS of the silent cell is indicated by point E. As described above, when the PTS of the still image cell and the PTS of the silent cell are the same, it indicates that the reproduction start of the silent cell and the display of the still image are simultaneous. The difference between the first PTS of the next voice cell at the point F and the last PTS of the voice cell at the point D is the “voice pause time”. In addition, according to the MPEG2 regulations, the PTS gap must be 0.7 seconds or less. Therefore, in this figure, the first PTS of the silent cell at point B and the PTS of the still image cell are shown.
It is necessary that the difference between TS and the difference between the first PTS of the still picture cell and the last PTS of the audio cell at point D satisfy this.

FIG. 14 shows an example of a PGC for forming a title. In this example, there are five programs, programs # 1 and # 2 are AOB # 1, and programs # 3 and #
4 and # 5 are AOB # 2, and AOB # 1 on the recording medium.
Is recorded after AOB # 2. Further, both the program # 1 and the program # 2 have a still picture cell and a silent cell, and the program # 2 has two voice cells. Programs # 3 and # 4 have only silence cells, and program # 5 has only speech cells.

All voice cells have a playback time of 60 seconds (PT
S, 5,400,000), silence cell is 1 second (PTS
Assuming that the PTS of the still picture cell is the same as the first PTS of the silent cell, the program information can be described as shown in FIG. The size of the still image data is about 1.88 Mbit, the audio data is 48 kHz,
Assuming that 2 channels are used for 16-bit sampling, the number of packs of still image cells is 112, the number of packs of silent cells is 96, and the number of packs of audio cells is 5,760, as described in the cell information of FIG. .

The audio title set has been described above, and the audio manager will now be described with reference to FIG.

(3.2) Data Structure of Audio Manager 900 The audio manager 900 is information for reproduction control which is first referred to when an optical disc is mainly reproduced by a disc reproducing apparatus.

FIG. 9 shows the data structure of the audio manager 900.

The audio manager 900 includes “audio manager information (AMGI)”, “audio manager menu VOB (AMGM_VOBS)”,
"Audio Manager Information Backup (AMGI_
BUP)].

Further, the audio manager information (A
MGI) ”is“ Audio manager information management table (AMGI_MA) having attribute information and pointer information.
T) "," Audio title management information "describing the number of audio titles, etc.," Audio title search pointer (ATT_SRP) "describing audio title search information, and PGC information for audio manager menu. "Audio manager menu PGC management information table (AMGM
_PGCI_UT)].

Further, "audio title search pointer (ATT_SRP)" includes "audio title type" for describing the type of each title, "number of programs in the title" for describing the number of programs included in the title, and reproduction time of the title. "Title playback time", which describes the number of the audio title set to which each title belongs, "audio title set number",
It includes an "ATS title number" that describes the title number in the audio title set of each title and an "ATS address" that describes the address of the audio title set to which each title belongs.

The description of the audio zone area has been completed, and the description of the DVD which is a multimedia optical disk has been completed. Next, the reproducing apparatus will be described.

First, the appearance of a DVD player, which is a playback device for a multimedia optical disk, will be described. FIG. 24 is a diagram showing the appearance of the DVD player 1, the television monitor 2, and the remote controller 91.

The DVD player 1 has an opening in the front of the housing, and a drive mechanism for setting an optical disk is provided in the depth direction of the opening.

At the front of the DVD player 1, there is provided a remote control receiving section 92 having a light receiving element for receiving infrared rays emitted from the remote control. Reference numeral 92 issues an interrupt signal indicating that the key signal has been received.

Furthermore, on the back of the DVD player 1,
A video output terminal and an audio output terminal are provided. By connecting an AV code to this terminal, a video signal reproduced from a DVD can be output to a large television monitor 2 for home use. This gives the operator 33 inches,
It is possible to enjoy DVD playback images on a large home-use television such as a 35-inch television. As can be understood from the above description, the DVD player 1 according to the present embodiment is not used by connecting to a personal computer or the like, but is used together with the television monitor 2 as household electric appliance.

The remote controller 91 is provided with a keypad which is biased by a spring on the surface of its housing, and outputs a code corresponding to a pressed key by infrared rays. FIG. 25 shows an operation panel of the operation remote controller 91. In this panel, "PO
"WER" key is the power ON / OF of DVD player 1
F is performed. The "MENU" key is used for calling the volume menu of the optical disk during the reproduction of the program chain. Numeric keys are used for chapter jumps in movies, music selection in music, and the like. The up, down, left and right cursor keys are used to select an item. The "ENTER" key is used to confirm the item selected by the cursor. When the cursor is moved on the item by the up, down, left, and right cursor keys, the item where the cursor exists is displayed in the select color of the item color information of the management information pack, and “ENTER” is displayed.
If confirmed with the key, it will be displayed in the confirmed color. In addition, keys common to other AV devices, such as "play", "stop", "pause", "fast forward", and "rewind" keys, are provided.

Next, the configuration of a DVD player, which is a playback device for a multimedia optical disk, will be described.

FIG. 13 is a block diagram showing the internal structure of the DVD player according to the present embodiment. This DV
The D player includes a drive mechanism 81 and an optical pickup 8
2. It includes a mechanism controller 83, a signal processor 84, an AV decoder 85, a remote controller receiver 92, and a system controller 93.

The drive mechanism 16 includes a base on which an optical disk is set, and a spindle motor that clamps the set optical disk and drives it to rotate. The base on which the optical disk is set is configured to move back and forth in and out of the housing by an eject mechanism (not shown).
The operator mounts the optical disk with the base moved to the outside of the housing. When the optical disk is mounted on the base and the base moves inside the DVD player, the optical disk
Loaded in D player.

The mechanism control unit 83 controls a mechanism system including a motor 81 for driving the disk and an optical pickup 82 for reading signals recorded on the disk. Specifically, the mechanism control unit 83 adjusts the motor speed according to the track position specified by the system control unit 93. At the same time, the pickup position is moved by controlling the actuator of the optical pickup 82, and when an accurate track is detected by the servo control, the apparatus waits for rotation until a desired physical sector is recorded and continuously starts from the desired position. To read the signal.

The signal processing section 84 amplifies, waveform-shapes, binarizes, demodulates, and outputs the signal read from the optical pickup 82.
The data is converted into a digital data string by performing processing such as error correction, and stored in a buffer memory (to be described later) in the system control unit 93 in units of logical blocks.

The AV decoder 85 receives the input VOB
Is subjected to a predetermined process to convert the digital data into a video signal or an audio signal. Specifically, A
The V decoder 85 further includes a system decoder 8
6, including a video decoder 87 and an audio decoder 89.

The system decoder unit 86 receives the digital data sequence transferred from the buffer memory in logical block (packet) units, determines the stream ID and substream ID in the header of each packet, , Audio data packs and management information packs. In this distribution, the moving image data pack is output to the video decoder 87. As for the audio data pack, only the audio data pack having the specified stream number according to the decode stream specification command input from the system control unit 93 is output.
9 is output. The management information pack is output to the system control unit 93. The moving image data pack input to the video decoder 87 is decompressed according to a predetermined method defined by MPEG2, output as digital video data, converted into an NTSC video signal, and output to the outside. The audio data input to the audio decoder 89 for the AV decoder is decoded by the LPCM or AC3 method according to the data type, D / A converted, and output to the outside as an audio signal.

The audio decoder 94 performs predetermined processing on the input AOB digital data according to the data type, converts the digital data into an audio signal, and outputs the audio signal to the outside.

The system control unit 93 includes a working memory,
It is configured integrally with a CPU and controls the entire DVD player.

The operation of the disk reproducing apparatus of the present embodiment configured as described above will be described below.

When a DVD optical disk is loaded in a DVD player, the system control section 93 detects the loading of the optical disk from an optical sensor or the like. When detecting the loading of the optical disk, the system control unit 93 controls the rotation of the disk by controlling the mechanism control unit 83 and the signal processing unit 84, and performs the initialization operation by seeking the optical pickup 82 to the lead-in area. , Start playing.

At the start of playback, the system control unit 93 determines whether or not the playback mode is a video-centered playback mode by using a playback mode determination unit. If the playback mode is determined to be the video-centric playback mode, the video manager is read based on the information read from the volume / file management area. The system control unit 93 includes a menu PGC for the video manager.
With reference to the management information table, the recording address of the program chain for the volume menu is calculated, reproduced, and stored inside. If the program chain for the volume menu is held inside, the system control unit 93
Calculates the video object (VOB) to be reproduced and its recording address on the optical disk with reference to the stored PGC information. When the video object to be reproduced is determined, the system control unit 93
3, a control signal is output to the signal processing unit 84, and the determined video object is taken out of the optical disc and reproduced. As a result, a video menu for allowing the user to select a title to be reproduced is displayed.

It is assumed that the operator sees this video menu and selects and confirms a menu item of interest. That is, it is assumed that the number of one of the menu items is designated by the remote controller. At this time, the system control unit 93, which has received the designation of the menu item number from the remote controller,
The control command corresponding to the designated number is executed by referring to the management information pack included in the VOB of the video menu being reproduced, which is input from Step 5. The control command is Play
Title #n, etc., where n designates a title number to be reproduced. As an execution operation by the PlayTitle command, the system control unit 93 refers to a title search pointer table which is a part of the audio manager, and sets the audio title set (AT
S), and the title number in the ATS. When the audio title set is determined, the system control unit 93
Outputs a control signal to the mechanism control unit 83 and the signal processing unit 84, reproduces the audio title set management information of the determined title set, and outputs the audio title set title search pointer table which is a part of the audio title set management information. Take out inside. If the video title set section title search pointer table can be extracted, the system control section 93 refers to this and refers to the PGC of the program chain for starting reproduction of the title to be reproduced.
Determine information. When the PGC information is determined, the system control unit 93 outputs a control signal to the mechanism control unit 83 and the signal processing unit 84, reproduces the determined PGC information, and stores this in an internal PGC information buffer. . When the PGC information for starting the reproduction of the title is stored, the system control unit 93 determines the audio object to be reproduced and its recording address with reference to the stored PGC information, and reproduces the determined video object. A control signal is output to the mechanism control unit 83 and the signal processing unit 84 for execution.

After that, the system control unit 93 sets the P
According to the GC information, the audio objects to be reproduced are sequentially determined and the reproduction control is performed. The system control unit 93
When the reproduction of the final audio object indicated by the GC information is completed, the PGC information of the next title is searched for, and the audio object described in the PGC information is similarly reproduced. In this way, all titles are reproduced and the process ends. In this case, depending on the setting of the player or the disc, the reproduction of one title may end, the reproduction of the title may end, or a menu may be displayed.

Next, a method for reproducing still picture cells, silent cells, and audio cells will be described in detail.

FIG. 19 is a diagram showing a conventional voice cell reproducing method. Conventionally, when reproducing such an MPEG2 stream, first seek to the head of the audio cell pack 14 and start reading data, but audio output cannot be started immediately, and a certain playback device After the idle time determined for each time has elapsed, the audio output is started.
The idle time is the time required to determine the PTS of the audio data, the time required to determine that the audio data is correct, and the time required to transition the muting circuit of the analog output unit from the muting state to the non-muting state. , Which is a different value for each playback device. In particular, when the disc playback device and the decoder are separate casings,
Since the determination of the PTS and the determination that the audio data is correct are performed independently, the idle time tends to be long.

FIGS. 17A and 17B are diagrams showing a reproducing method in which only a sound is reproduced without displaying a still image even when there is a still image cell. FIG. 17A shows a case where reproduction is performed from the beginning, and FIG. 17B shows a method of performing reproduction continuously from the previous audio cell.

When a title or a program is selected from the beginning or from a menu or the like to be jumped and reproduced, first jump to the first pack of the silent cell with reference to the start address of the cell information. At this time, the STC, which is the reference time of the decoder, is set to the SC of the first pack of the silent cell.
Set with R. Next, data skip or jump is performed for a predetermined idle time while watching the PTS of the silent cell, and the silent time corresponding to the idle time is reproduced. During this time, audio output is prepared. At this time, the next title number is not displayed on the display device of the playback device, and the playback elapsed time is not updated. As soon as the PTS at the beginning of the audio cell is detected, the audio output is started, the title number is displayed, and the elapsed playback time is updated. The playback device will behave. When the reproduction is continued from the previous audio cell, the still image pack is jumped, and the silent cell is also jumped or skipped so as to leave the idle time. At this time, if the STC serving as the reference of the system time is kept counting, the interval from the completion of the voice of the previous voice cell to the voice output of the next voice cell becomes equal to the voice pause time. However, the continuation of the counting of the STC is when both the physical allocation information and the time attribute information have a value indicating “continuous”, and when either one indicates “discontinuous”, the jump from the menu is performed. The STC is reset at the beginning of the silent cell pack. Even when there is no still image cell, the method is almost the same. In the case where there is no silent cell and the reproduction is started from the beginning, the operation is the same as the conventional one shown in FIG. When playing back from the previous voice cell, if the time attribute information indicates “continuous”, the voice cell is decoded as it is following the previous voice cell,
Output audio. When the time attribute information indicates “discontinuous”, the operation is the same as that of the related art in FIG. 19, as in the case of reproducing from the beginning.

FIGS. 18A and 18B show a case where a still image is displayed and sound is reproduced. FIG. 18A shows a case where reproduction is performed from the beginning, and FIG. 18B shows a method of performing reproduction continuously from the previous audio cell.

When reproducing from the beginning or when jumping by selecting from a menu or the like, first, a seek is made to a pack of still picture cells from the cell information, the still picture cells are read, and the still picture is decoded. At this time, the SCR of the first pack of the still image cell is used as the reference time of the decoder.
Set TC. Next, the head pack of the silent cell is read. If STC becomes STC of still picture cell,
Display a still image. The rest is the same as without a still image.
The display of a still image may be performed during the processing of a silent cell, or simultaneously with or after the start of output of an audio cell, within the range permitted by the MPEG2 standard. When playing continuously from the previous audio cell, when it becomes a still image pack,
Read and decode still image cells. Next, the processing of the silent cell is performed. As with the case where there is no still image, the presence or absence of the STC set differs depending on the time attribute information. Subsequent processing is the same as when there is no display of a still image. However, display of a still image is performed when the STC becomes the PTS of the still image cell, and the STC is set to the SC
The difference is that R is performed.

FIGS. 20 to 23 are flowcharts showing a method of reproducing one of the programs. If the physical allocation information of the program information indicates "continuous" and the program reproduced before has a program number one less than the program to be reproduced, the disk read head need not be particularly sought. Also, when the time attribute information indicates "continuous", it is not necessary to reset the STC, which is the reference time of the decoder, when the reproduction is continued from the previous program.

The determination as to whether a cell is a still picture cell can be made by using the cell type of the cell information or by using the still picture flag of the program information. The determination of a silent cell is made based on the cell type of the cell information. The last determination of the cell is made by comparing the end address of the cell information with the address of the data read from the disk. The end of the program reproduction can be determined by returning the cell index of the cell information to 0, or by changing the cell type to a still image cell or a silent cell, or by the start cell number of the next program in the program information.

The skipping of the silent cell is performed while detecting the PTS at the time of decoding the silent cell, or by determining the number of packs to be skipped from the data rate and skipping.

As described above, according to the second embodiment, the MP
Since the program reproduction information describing the start time of each audio data and the reproduction time with reference to the reproduction start time of the audio data at the head of the EG2 stream is recorded in the management area as a part of the reproduction control information, high quality To provide a multimedia recording medium capable of reproduction by adding video data to a digital audio data at a limited bit rate, and an inexpensive reproduction device,
Even in a playback device that does not have a playback function of video data, the interval of audio playback can be made constant, and the title creator can easily create data.

[0165]

According to the present invention, even for a plurality of reproducing apparatuses having different performances such as data processing speed, the waiting time (startup period) generated at the start of reproduction of the system stream does not vary. be able to.

[Brief description of the drawings]

FIG. 1 shows a system stream 210 conforming to MPEG.
FIG. 3 is a diagram showing a data structure of FIG.

FIG. 2A shows a plurality of audio packs A1 to A6 and an audio pack A;
It is a figure which shows the relationship with SCR and PTS given to each of 1-A6.

FIG. 2B is a diagram showing timing for reproducing a system stream 210.

FIG. 3 is a diagram showing a data structure of a system stream 310 stored on the optical disc according to the first embodiment of the present invention.

FIG. 4A shows a plurality of audio packs S1 to S8, A1 to A14.
FIG. 4 is a diagram showing a relationship between the audio packs S1 and S8 and the SCR and PTS assigned to each of the audio packs A1 to A14.

FIG. 4B is a diagram showing timing for reproducing a system stream 310.

FIG. 5 is a diagram showing a configuration of a playback device 400 according to Embodiment 1 of the present invention.

FIG. 6A is an external view of an optical disc according to Embodiment 2 of the present invention.

FIG. 6B is a sectional view of the optical disc according to the second embodiment of the present invention.

FIG. 6C is an enlarged cross-sectional view of the optical disc according to the second embodiment of the present invention.

FIG. 6D is a diagram showing pits formed on the optical disc according to the second embodiment of the present invention.

FIG. 7A is a diagram showing a track structure of the optical disc shown in FIG. 6A.

FIG. 7B is a diagram showing a sector structure of the optical disc shown in FIG. 6A.

FIG. 8 is a diagram showing a logical structure of the optical disc shown in FIG. 6A.

FIG. 9 is a diagram showing a data structure of an audio manager.

FIG. 10 is a diagram showing a data structure of an audio title set.

FIG. 11 is a diagram illustrating a configuration example of an audio object (AOB).

FIG. 12 is a diagram showing a data structure of PGC information and Cell information.

FIG. 13 is a block diagram showing the internal structure of a DVD player as a playback device.

FIG. 14 is a diagram illustrating an example of a PGC that forms a title.

FIG. 15 is a diagram illustrating an example of program information.

FIG. 16 is a diagram illustrating an example of Cell information.

FIG. 17A is a diagram showing a procedure when reproducing sound without a still image.

FIG. 17B is a diagram showing a procedure for reproducing sound without a still image.

FIG. 18A is a diagram showing a procedure when a still image is displayed and sound is reproduced.

FIG. 18B is a diagram showing a procedure when a still image is displayed and sound is reproduced.

FIG. 19 is a diagram showing a conventional procedure for reproducing sound.

FIG. 20 is a diagram showing a schematic flow when performing program reproduction.

FIG. 21 is a diagram showing a flow when reproducing a head audio cell.

FIG. 22 is a diagram showing a flow when reproducing a silent cell.

FIG. 23 is a diagram showing a flow when reproducing a continuous cell.

FIG. 24 is a diagram showing a DVD device and peripheral devices connected thereto.

FIG. 25 is a diagram for explaining a configuration of a remote controller used when operating the DVD device.

[Explanation of symbols]

 210 System stream 320 Audio pack 312 Silent cell 314 Audio cell 400 Playback device 410 Optical disk 420 Readout unit 430 Playback unit 432 Decoder 434 Output unit 436 Muting circuit 438 Control unit

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification symbol FI H04N 5/781 H04N 5/92 H 5/92 5/93 Z 5/93 (72) Inventor Tadashi Abe Tadashi Okadoma, Kadoma City, Osaka 1006 Matsushita Electric Industrial Co., Ltd.

Claims (15)

[Claims] 1. An information recording disk for storing at least one system stream, wherein the system stream includes a silent cell defining a silent period and an audio cell defining audio data to be reproduced after the silent period. The silence period includes: after the system stream to be reproduced is determined from at least one system stream stored in the information recording disc, reproduction of the audio cell included in the determined system stream. Information recording disk, which is the period during which silence should occur until the start of the operation. 2. In the silent period, reproduction of the determined system stream is started after a system stream to be reproduced among the at least one system stream stored in the information recording disc is determined. 2. The information recording disk according to claim 1, wherein the information recording disk includes a period required by the reproducing apparatus before the recording. 3. The information recording disk further stores information indicating a reproduction order of a plurality of system streams, and during the silence period, after the reproduction of one of the plurality of system streams ends, the next system 2. The information recording disk according to claim 1, wherein the period is a period in which silence is required until reproduction of an audio cell included in the stream is started. 4. The silent cell and the audio cell each include audio data encoded in the same encoding mode, and an output level of the audio data included in the silent cell is substantially zero. The information recording disk according to claim 1. 5. The system stream is provided with a time stamp defining an output timing at a predetermined interval, and a presentation period of the audio cell includes a first time stamp and a last type assigned to the audio cell. The information recording disk according to claim 1, wherein the information recording disc is determined based on a difference from a stamp, and the silent period is determined based on a difference between a first time stamp and a last time stamp given to the silent cell. . 6. A reproducing apparatus for reproducing an information recording disk, wherein the information recording disk stores at least one system stream, wherein the system stream includes a silent cell that defines a silent period, and a silent cell that defines a silent period. Audio cells defining audio data to be reproduced later, wherein the silent period is determined after a system stream to be reproduced is determined from at least one system stream stored in the information recording disc. A period during which the audio cells included in the reproduced system stream are to be silenced before the reproduction of the audio cells is started, and the reproduction device is to reproduce from at least one system stream stored in the information recording disc. A reading unit for reading a system stream; From the middle of the silent cell included in the issued system stream, and a reproduction section for reproducing a part and the audio cell of the silent cell, the reproducing apparatus. 7. In the silent period, reproduction of the determined system stream is started after a system stream to be reproduced is determined among the at least one system stream stored in the information recording disc. The playback device according to claim 6, wherein the playback device includes a period required by the playback device. 8. The information recording disk further stores information indicating a reproduction order of a plurality of system streams, and during the silence period, a next system after completion of reproduction of one of the plurality of system streams. The reproducing device according to claim 6, wherein the period is a period in which silence is required until reproduction of an audio cell included in the stream is started. 9. Each of the silent cell and the audio cell includes audio data encoded in the same encoding mode, and an output level of the audio data included in the silent cell is substantially zero. The playback device according to claim 6. 10. The system stream is provided with a time stamp that defines an output timing at predetermined intervals, and a presentation period of the audio cell includes a first time stamp and a last type assigned to the audio cell. The playback device according to claim 6, wherein the reproduction time is determined based on a difference from a stamp, and the silent period is determined based on a difference between a first time stamp and a last time stamp given to the silent cell. 11. A reproducing method for reproducing an information recording disk, wherein the information recording disk stores at least one system stream, wherein the system stream includes a silent cell that defines a silent period, and a silent cell that defines the silent period. Audio cells defining audio data to be reproduced later, wherein the silent period is determined after a system stream to be reproduced is determined from at least one system stream stored in the information recording disc. A period during which the audio cells included in the reproduced system stream are to be silenced until the reproduction of the audio cells is started, and the reproduction method is to reproduce from at least one system stream stored in the information recording disk. Reading a system stream; From the middle of the silent cell included in the issued system stream, comprising the steps of reproducing a portion between the audio cell of the silent cell, playback method. 12. In the silence period, reproduction of the determined system stream is started after a system stream to be reproduced among the at least one system stream stored in the information recording disc is determined. The reproducing method according to claim 11, further comprising a period required by the reproducing apparatus before the reproduction. 13. The information recording disk further stores information indicating a reproduction order of a plurality of system streams, and during the silence period, a next system after the reproduction of one of the plurality of system streams is completed. The reproduction method according to claim 11, wherein the period is a period in which silence is required until reproduction of an audio cell included in the stream is started. 14. The silent cell and the audio cell each include audio data encoded in the same encoding mode, and an output level of the audio data included in the silent cell is substantially zero. Claim 1
2. The reproduction method according to 1. 15. The system stream is provided with a time stamp that defines an output timing at predetermined intervals, and a presentation period of the audio cell includes a first time stamp and a last type assigned to the audio cell. The reproduction method according to claim 11, wherein the silent period is determined based on a difference from a stamp, and the silent period is determined based on a difference between a first time stamp and a last time stamp given to the silent cell.