JP2002218398A - Recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording medium for recording various AV streams which enables random accessing of a transport stream and an apparatus, and to provide a method of recording and reproducing on such recording medium. SOLUTION: In the recording medium and the apparatus and the method of recording and reproducing on such recoding medium, arrival time information of an MPEG-TS packet arriving at a recorder are added to a specified MPEG-TS packet with a variable length and variable precision, an integral number of these are combined to form a real data part, specific information are added to every real data part to constitute a data unit of a fixed data length, and the size of the data unit is a fixed length equal to an integral multiple or fraction of ECC blocks on the recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a readable and writable recording medium, and more particularly to a recording medium for recording multimedia data including moving image data, still image data, and audio data in various formats. . Furthermore, the present invention relates to an apparatus and a method for recording and reproducing information on and from such a recording medium,
The present invention relates to an apparatus and a method capable of efficiently recording a PEG-TS packet and its arrival time information.

[0002]

2. Description of the Related Art In recent years, DVDs (Digital Ver.
2. Description of the Related Art In addition to being used as a storage medium for a computer, a ROM type optical disk such as a side disc (ROM) is used as video data of a movie or the like (hereinafter referred to as AV data).
It is used for recording. Further, as a recordable information recording medium, a phase-change disk DVD-RAM disk having a capacity of several GB (hereinafter abbreviated as DVD-RAM)
Has been put to practical use.

[0003] Combined with the practical use of MPEG (MPEG2), an international standard encoding standard for digital AV data, DVD-RAM is expected not only as a computer but also as a recording / reproducing medium in the audio / video (AV) technology field. Have been. In other words, conventional typical AV
It is expected to spread as a medium that replaces the magnetic tape that is a recording medium.

[0004] A major challenge in the future is how to record AV data including image data using these optical disks aiming at increasing the capacity and to realize performance and new functions that greatly exceed conventional AV equipment.

[0005] The greatest feature in the transition to a disk is a significant improvement in random access performance. In the case of random access to the tape, it usually takes several minutes to rewind one tape. This is orders of magnitude slower than the seek time (about several tens of ms) in optical disk media. Thus, tape cannot be a random access device in practice.

With such random access performance, distributed recording of AV data, which was impossible with a conventional tape, has become possible with an optical disk.

FIG. 1 is a block diagram of a drive device of a DVD recorder. The drive device includes an optical pickup 11, which reads data from the DVD-RAM disk 10,
CC (Error Correcting Code)
A processing unit 12, a track buffer 13, a switch 14 for switching input / output of the track buffer 13, an encoder unit 15 and a decoder unit 16 are provided.

As shown in FIG. 1, data is recorded on the DVD-RAM disk 10 with 1 sector = 2 KB as a minimum unit. Further, the ECC processing unit 12 performs error correction processing as 16 sectors = 1 ECC block.

The track buffer 13 is a DVD-RAM
A buffer for recording AV data at a variable bit rate in order to record AV data on the disc 10 more efficiently. While the read / write rate to the DVD-RAM 100 is a fixed rate, the bit rate of AV data changes according to the complexity of its contents (images in the case of video). Used as a buffer for

By using the track buffer 13 more effectively, it is possible to continuously supply the AV data to the decoder 16 even when the AV data is discretely arranged on the disk 10. Also, in the case of recording, the AV data sent to the encoder unit 15 can be recorded on a DVD-RAM.

[0011] This large-capacity recording medium, DVD-R
In order to use AM more effectively, DVD-RAMs use a UDF (Universal Disc Format).
t) A file system is mounted to enable access on a PC. For details on the UDF file system, see "Un
versal Disc Format Stand
ard ".

Next, a description will be given of the AV equipment which has been conventionally used. FIG. 4 shows conventional AV devices and media,
FIG. 4 is a diagram showing a format relationship.

For example, if a user wants to watch a video, it is natural to put a video cassette in a VTR and watch it on a television. It was natural to listen through headphones. That is, the conventional AV device is paired with one medium corresponding to one format (video or audio). For this reason, users need to always replace media and AV equipment for what they want to see and hear,
I felt inconvenient.

[0014] Further, with the recent spread of digital technology, DVD video discs have become available as package software.
Digital satellite broadcasting has been put to practical use as a broadcasting system. Under these circumstances, it goes without saying that there is innovation in digital technology, especially practical application of MPEG.

FIG. 5 is a diagram of an MPEG stream used in the DVD video disk and digital satellite broadcasting described above. The MPEG standard has a hierarchical structure as shown in FIG.

What is important here is that the stream of the MPEG system layer finally used by the application is:
This is different between a package media system such as a DVD video disc and a communication media system such as digital satellite broadcasting.

The former is called an MPEG program stream (hereinafter referred to as MPEG-PS), and data is transferred in units of packs in consideration of a sector (2048 bytes in the case of DVD) which is a recording unit of a DVD video disk or the like. MPEG transport stream (hereinafter MPEG)
-TS), and data transfer is performed in units of 188-byte TS packets in consideration of ATM in particular.

It has been expected that AV data can be freely handled without depending on the media by digital technology and MPEG which is a video / audio coding technology. There are no AV devices or media that are compatible with both communication media.

With the advent of large-capacity optical disks such as DVD-RAMs, it is expected that the inconvenience felt by conventional AV equipment will be eliminated.

Especially, with the start of digital satellite broadcasting, MP
There is a demand for a recording system capable of recording EG-TS in the same manner as MPEG-PS.

[0021]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to construct a system for efficiently recording an MPEG-TS stream on a large-capacity random-access recording medium such as a DVD. . Especially MPEG
An object of the present invention is to effectively manage the arrival time of a TS packet and record the data in a data unit having high affinity with an ECC block with good accessibility.

[0022]

In order to solve this problem, the present invention converts arrival time information (ATS) at which an MPEG-TS packet arrives at a recording device into a predetermined MPEG-TS packet with variable length and variable precision. A data unit (capsule) having a fixed data length with unique information (capsule header) added for each real data portion is constructed. A recording medium, a recording / reproducing apparatus, and a method, wherein the size of the capsule is a fixed length that is an integral multiple or a fraction of an ECC block of the recording medium.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a recording medium according to the present invention will be described in detail with reference to the accompanying drawings.

The recording medium according to the present invention enables recording of AV data of various formats on a single medium, and enables uniform management of these data. This makes it possible to record video data in which terrestrial broadcasting is recorded as MPEG-PS and MPEG-TS transmitted as digital broadcasting in one recording medium.

Further, these data recorded on the recording medium can be reproduced in a predetermined order. For this purpose, the recording medium according to the present invention includes management information for managing the AV stream without depending on the type of the format of the AV data. Hereinafter, MP which is a feature of the present invention will be described.
A recording medium recorded in an efficient recording format of the EG-TS stream will be described in detail.

FIG. 2 shows an embodiment of a recording format for recording MPEG-TS on a recording medium. In FIG. 2, reference numeral 1000 denotes recording data which is AV data recorded on the recording medium, and 1001 denotes recording data 1000. Capsules 1002, which are fixed-length data, are added to each capsule 1001, and a capsule header that stores unique information of the capsule 1001 is an MPEG-TS.
ATS 1004, which is time information for specifying the arrival time added to the packet, is an MPEG-TS packet.

The structure of an embodiment of the capsule header 1002 will be described with reference to FIG. In FIG. 3, 10
Reference numeral 10 denotes an ID for identifying a capsule, 1011 denotes storage information indicating the number of MPEG-TS packets stored in the capsule, and 1012 describes information on precision and overflow of ATS stored in the capsule. AT
S complement information 1014 is information indicating the copyright protection (scramble) state of the capsule.

The ATS supplementary information 1012 includes at least ATS accuracy information 10 indicating the accuracy of the ATS in the capsule.
16 and can be changed in capsule units according to the bit rate of the input MPEG-TS stream.

FIG. 6 shows a system for performing recording / reproduction in such a recording format. In FIG. 6, 1060
Is a system control unit having a reference time signal oscillating unit (clock) in the system, and 1061 is an input MPEG-T
This is a decoding control unit that encodes the S stream into the format shown in FIG.
An ATS generation unit for generating an ATS from packet arrival time information is included.

Reference numeral 1062 denotes a decoding control unit for performing a decoding process at the time of reproduction. The decoding control unit 1062 interprets the ATS of each MPEG-TS packet read from the recording medium and synchronizes with the clock inside the system control unit 1060. Then, the packet arrival time interval at the time of recording is restored, and decoding processing is performed.

Reference numeral 1063 denotes a drive for controlling the recording medium. Reference numeral 1064 denotes a reproduction management information processing unit, which generates management information of recording data at the time of recording, and determines where the recording data is recorded on the recording medium at the time of reproduction. Is read, and the playback section is instructed to the drive 1063.

The operation at the time of recording in a system including such a recording / reproducing apparatus and a recording medium will be described.

When a user-desired MPEG-TS stream is input to the encoding control unit 1061, the ATS generation unit included in the encoding control unit 1061 sends an individual MPEG-TS stream.
The absolute time when the TS packet arrives is stored in the system control unit 106
The reference time obtained from the clock within 0 is referred to and stored.

MPE stored in encoding control section 1061
When the number of G-TS packets reaches the number of packets forming one capsule, the ATS is described with a desired time accuracy that can correctly describe the ATS within one capsule.

At this time, the pattern that can take the description accuracy of the ATS can be set from the range that can be specified in the ATS accuracy information 1016 shown in FIG. When recording time information and a stream with a low bit rate, time information with an accuracy of 90 KHz and a plurality of types of time accuracy are selected.

After the actual data to be stored in one capsule is determined in this way, the encoding control unit 1061 determines a capsule header and transfers the data for one capsule to the drive 10.
Transfer to 63.

The drive 1063 receiving this records the ECC block on the recording medium so that one capsule does not straddle the ECC block. When the input of the MPEG-TS stream is completed (for example, when the user instructs to stop recording), the reproduction management information processing unit 1064 transmits the management information (data length) of the recording data transferred from the encoding control unit 1061 as needed. And information such as recording time) are collected and transferred to the drive 1063, and the drive 1063 records this as a predetermined file on a recording medium.

On the other hand, when reproducing the AV data recorded on the recording medium, the system control unit 1060, which has received an instruction from the user, reproduces the reproduction management information such as the address where the desired content is recorded. Information processing unit 10
64 and request from the drive.

The drive 1063 sets A from the desired address.
The reading of the V data is started, and the AV data (capsule) is transferred to the decoding control unit 1062.

The ATS judging unit in the encoding control unit interprets the capsule header of the read capsule, specifies the accuracy of the ATS described, and converts each MPEG-TS packet into MPEG according to the reference time of the system. The signal is sent to a decoding unit, which is sequentially decoded and output as an AV signal.

Therefore, in the case of the present embodiment, it is possible to flexibly cope with the bit rate of the input stream by changing the time accuracy of the ATS with respect to the transfer rate of the input stream, and to record the MPEG-TS efficiently. is there.

The size of the capsule 1001 shown in FIG. 2 is 16 KB, 32 KB, 64 KB, 128 KB or the like.
It may be an integer fraction or an integral multiple of the CC block (32 KB).

The ATS 1003 (the first ATS in the capsule) shown in FIG. 2 may have the same byte length as the ATS in the same capsule, and indicates the absolute time as the arrival time information of the MPEG-TS packet. Even one
The time information may be time information used to indicate a difference between the arrival times of the immediately preceding MPEG-TS packets.

When recording at a fixed bit rate such as digital broadcasting, it is conceivable to extract and record only necessary MPEG-TS packets.
Equivalent time information can be generated by recording the number of TS packets as ATS. In this case, the number of invalid packets may be described as ATS, and the ATS accuracy information 1016 may indicate that fact.

That is, the ATS accuracy information 1016 contains the MPE
A flag indicating that the number of invalid G-TS packets has been indicated, and an MP in which the ATS in the capsule has arrived immediately before.
By indicating the number of invalid packets transferred between the EG-TS packet and each MPE from the bit rate of the broadcast multiplexed with other programs described in the reproduction management information, etc.
It is possible to easily calculate the arrival time of the G-TS packet. Also in this case, the first ATS in the capsule
Only, it is similarly possible to describe time information indicating an absolute time.

Further, when MPEG-TS packets, which are programs to be recorded, arrive continuously, the ATS is omitted from the second and subsequent packets in the continuously arrived packet group, and the ATS is omitted. The specified information of the packet may be described as an ATS omitted packet number shown in FIG.

When the actual data size in the capsule is variable as described above, or in the capsule at the end of the recording data, padding to an unused area in the capsule as shown in FIG. May be inserted.

The ATS supplementary information 1012 shown in FIG.
May be information composed of only the ATS precision information 1016 or information composed of only the ATS digit overflow information 1017.

It should be noted that the TS packet storage information 1011 shown in FIG. 3 indicates whether the number of stored MPEG-TS packets in the capsule is equal to the number of MPEG-TS packets in the capsule.
It may be information for specifying the arrangement position of the packet.

As shown in FIGS. 13 and 14, each M
A capsule header may be added to the PEG-TS packet, and each ATS may be included in the capsule header.

Note that a plurality of streams can be simultaneously recorded in one recording file using the ID 1010 shown in FIG.

As shown in FIG. 15, when simultaneously recording a plurality of MPEG-TS streams having different input systems or the like, different identification numbers are assigned to the respective input streams, and recording is performed while interleaving the capsules. This allows simultaneous recording of multiple streams into one file, and the ID of the capsule header during playback.
, It is possible to extract only a desired stream. Since this interleaving recording method drastically reduces the number of seeks occurring during recording, it is very effective for a recording medium such as an optical disk which has a problem in seek performance.

In order to protect the copyright of the AV file recorded on the recording medium, it is necessary to perform scramble processing on the recorded data. At this time, in the encryption unit 1065 of FIG. 6, at least the capsule header is not scrambled, so that the structure of the recording data can be easily interpreted without descrambling.

Further, if there is an ATS indicating an absolute time, the ATS is not scrambled or all ATSs are processed.
It is conceivable that the scrambling process is not performed including the TS. These embodiments are shown in FIGS.

[0055]

As described above, according to the present invention, information specific to the capsule is stored in a capsule which is a fixed data unit of an integral multiple or a fraction of an ECC block which is a read / write unit of a recording medium. Equipped with a capsule header,
ATS that can describe the arrival time of a predetermined MPEG-TS packet with variable precision for each capsule,
Storing an integer number of sets with PEG-TS packets enables flexible AT from low bit rates to high bit rates.
S-accuracy is changed and MPEG-
TS packet can be stored and the capsule is E
Since it has a high affinity with the CC block length, extra seek and reading can be suppressed, and MPEG-TS is recorded and recorded.
It is possible to construct a highly efficient system for reproduction.

[Brief description of the drawings]

FIG. 1 is a block diagram of a drive device of a DVD recorder.

FIG. 2 is a data structure diagram of a recording format according to an embodiment of the present invention.

FIG. 3 is a data structure diagram of a capsule header according to an embodiment of the present invention;

FIG. 4 is a diagram showing a relationship between a conventional AV device and a medium.

FIG. 5 is a diagram showing the structure of MPEG-PS and MPEG-TS.

FIG. 6 is a block diagram of a recording / reproducing apparatus according to an embodiment of the present invention;

FIG. 7 is a diagram showing a relationship between an AV file and a directory and an address space on a disc.

FIG. 8 is a data structure diagram of a recording format according to an embodiment of the present invention.

FIG. 9 is a data structure diagram of a recording format according to an embodiment of the present invention.

FIG. 10 is a data structure diagram of a recording format according to an embodiment of the present invention.

FIG. 11 is a data structure diagram of a recording format when ATS is omitted according to an embodiment of the present invention;

FIG. 12 shows padding according to an embodiment of the present invention;
Data structure diagram of dummy packet recording format

FIG. 13 is a data structure diagram of a recording format according to an embodiment of the present invention.

FIG. 14 is a data structure diagram of a recording format according to an embodiment of the present invention.

FIG. 15 is a data structure diagram of an interleaved arrangement recording format according to an embodiment of the present invention;

FIG. 16 is a diagram showing scrambling processing of a recording format according to an embodiment of the present invention;

FIG. 17 is a diagram showing scrambling processing of a recording format according to an embodiment of the present invention.

FIG. 18 is a diagram showing scrambling processing of a recording format according to an embodiment of the present invention.

FIG. 19 shows a description example of ATS at the beginning of ATS in a capsule.
Is a diagram for comparing and explaining the case of the absolute time (27 MHz)

FIG. 20 is a flowchart for explaining ATS accuracy change processing;

[Explanation of symbols]

 Reference Signs List 10 DVD-RAM disk 11 Optical pickup 12 ECC processing unit 13 Track buffer 14 Track buffer switch 15 Encoder unit 16 Decoder unit 1000 Recording data 1001 Capsule 1002 Capsule header 1003 ATS 1004 MPEG-TS packet 1010 ID 1011 TS packet storage information 1012 ATS complement Information 1014 Copyright protection information 1016 ATS accuracy information 1017 ATS overflow information 1060 System control unit 1061 Encoding control unit 1062 Decoding control unit 1063 Drive 1064 Playback management information processing unit 1065 Encryption unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Tomotaka Yagi, Inventor 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5C052 AA02 AB03 AB04 CC11 CC12 5C053 FA24 GB06 GB15 GB37 JA21 JA22 5D044 AB05 AB07 BC06 CC04 DE02 DE03 DE14 DE39 DE68 GK08

Claims (1)

[Claims] 1. A recording medium for recording an MPEG transport stream (hereinafter referred to as MPEG-TS), comprising: a recording unit (hereinafter referred to as a capsule) which is an integral multiple or a fraction of an ECC block (error correction block) length of the recording medium. ), An MPEG-TS is recorded, and a capsule header indicating unique information of each capsule, an integer number of MPEG-TS packets,
ATS (Application Time Stamp) describing the arrival time of each of the MPEG-TS packets
p) is stored, and at least information indicating the time accuracy of the ATS is described in the capsule header.