Method disk and an apparatus for system encoding of bitstreams including plural system streams to be seamlessly reproduced

• US 5,905,845 A
• Filed: 09/27/1996
• Issued: 05/18/1999
• Est. Priority Date: 09/29/1995
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ishihara, Hideshi, Okada, Tomoyuki, Hasebe, Takumi, Tsuga, Kazuhiro, Hamasaka, Hiroshi, Nakamura, Kazuhiko, Mori, Yoshihiro
• Primary Examiner(s): TRAN, THAI Q
• Application Number:
  US08/724,232
• Time in Patent Office: 963 Days
• Field of Search: 386/39, 386/45, 386/95-107, 386/109, 386/111-112, 386/125-126, 348/423, 348/512, 348/515
• US Class Current: 386/244
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: G11B 20/1251 for continuous data, e.g. digitised analog information signals, pulse code modulated [PCM] data
• CPC Class Codes: G11B 2020/1062 Data buffering arrangements, e.g. recording or playback buffers
• CPC Class Codes: G11B 2020/10944 Real-time recording or reproducing, e.g. for ensuring seamless playback of AV data
• CPC Class Codes: G11B 2220/235 Multilayer discs, i.e. multiple recording layers accessed from the same side
• CPC Class Codes: G11B 2220/237 having exactly two recording layers
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 27/329 on a disc [VTOC]
• CPC Class Codes: G11B 7/00745 Sectoring or header formats within a track formats in general G11B20/12
• CPC Class Codes: G11B 7/14 specially adapted to record on, or to reproduce from, more than one track simultaneously
• CPC Class Codes: H04N 5/92 Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
• CPC Class Codes: H04N 5/9208 involving the use of subcodes
• CPC Class Codes: H04N 5/9262 using predictive coding
• CPC Class Codes: H04N 5/9267 using time division multiplex of the PCM audio and PCM video signals

Abstract

An optical disk for recording more than one system stream containing audio data and video data. The audio data and video data of the plural system streams are recorded to the optical disk, and are interleaved such that the difference between the input start times of the video data and audio data to the video buffer in the video decoder and the audio buffer in the audio decoder is less than the reproduction time of the number of audio frames that can be stored in the audio buffer plus one audio frame.

Claims

1. An optical disk for storing a bit stream including a first system stream and a second system stream which are to be successively reproduced in that order by an optical disk reproduction apparatus, each of the first and second system streams including video data and audio data interleaved with each other, the optical disk reproduction apparatus including:

a decoder for decoding the video data and the audio data;

a video buffer for temporarily storing the video data; and

an audio buffer for temporarily storing the audio data, the audio data being capable of storing N audio frames of the audio data,

wherein the optical disk includes the audio data of the first system stream and the audio data of the second system stream being interleaved in such a manner that a time period between a time at which the input of the audio data of the first system stream to the audio buffer is completed and a time at which the audio data of the second system stream starts to be input to the audio buffer is equal to or shorter than a time period T, where T is a sum of a time period spent for outputting one audio frame decoded by the decoder and a time period spent for decoding and outputting the N audio frames stored in the audio buffer.

2. An optical disk according to claim 1, wherein the bit stream includes a plurality of second system streams which are alternatively reproduced, and

wherein the second system streams include the same audio contents having a duration equal to or longer than one audio frame at a head of the respective audio data.

3. An optical disk according to claim 1, wherein the bit stream includes a plurality of first system streams which are alternatively reproduced, and

wherein the first system streams include the same video contents having a duration equal to or longer than one video frame at an end of the respective video data.

4. An optical disk according to claim 3, wherein the first system streams include the same audio contents having a duration equal to or longer than one audio frame at an end of the respective audio data.

5. An optical disk for storing a bit stream to be reproduced by an optical disk reproduction apparatus, the optical disk reproduction apparatus including:

a decoder for decoding video data and audio data;

a video buffer for temporarily storing the video data; and

an audio buffer for temporarily storing the audio data, the audio buffer being capable of storing N audio frames of the audio data, the optical disk comprising;

a data area in which the bit stream is stored, the bitstream including a plurality of system streams, each of the system streams including the video data and the audio data interleaved with each other; and

an index area for storing root data indicating a reproduction order of the system streams and a plurality of seamless reproduction flags provided for every two of the system streams which are successive in a reproduction order defined by the root data, each of the seamless reproduction flags indicating whether or not the corresponding two successive system streams are to be seamlessly reproduced,

wherein the audio data of a former one of two successive system streams to be reproduced seamlessly and the audio data of a latter one are interleaved in such a manner that a time period between a time at which the input of the audio data of the former system stream to the audio buffer is completed and a time at which the audio data of the latter system stream starts to be input to the audio buffer is equal to or shorter than T, where T is a sum of a time period spent for outputting one audio frame decoded by the decoder and a time period spent for decoding and outputting the N audio frames which are stored in the audio buffer.

6. A method for generating a bit stream including a first system stream and a second system stream which are to be successively reproduced in that order by an optical disk reproduction apparatus, each of the first and second system streams including video data and audio data interleaved with each other, the optical disk reproduction apparatus including:

a decoder for decoding the video data and the audio data;

a video buffer for temporarily storing the video data; and

an audio buffer for temporarily storing the audio data, the audio buffer being capable of storing N audio frames of the audio data, wherein a sum of a time period spent for outputting one audio frame decoded by the decoder and a time period spent for decoding and outputting the N audio frames stored in the audio buffer is T1, the method comprising;

calculating a time period T2 between a time at which video data to be included in the second system stream starts to be input to the video buffer and a time at which audio data to be included in the second system stream starts to be input to the audio buffer;

modifying audio data to be included in the first system stream and the audio data to be included in the second system stream so that an end portion of the audio data to be included in the first system stream is transferred to be positioned at a head of the audio data to be included in the second system stream so as to make T2 equal to or shorter than T1, the transferred end portion of the audio data having a duration equal to or longer than one audio frame;

constituting the first system stream by interleaving the modified audio data and the video data which are to be included in the first system stream;

constituting the second system stream by interleaving the modified audio data and the video data which are to be included in the second system stream; and

constituting the bit stream by arranging the first system stream and the second system stream.

7. A method for generating a bit stream including a first system stream and a second system stream which are to be successively reproduced in that order by an optical disk reproduction apparatus, each of the first and second system streams including video data and audio data interleaved with each other, the optical disk reproduction apparatus including:

a decoder for decoding the video data and the audio data;

a video buffer for temporarily storing the video data; and

an audio buffer for temporarily storing the audio data, the audio buffer being capable of storing N audio frames of the audio data, wherein a sum of a time period spent for outputting one audio frame decoded by the decoder and a time period spent for decoding and outputting the N audio frames stored in the audio buffer is T1, the method comprising;

calculating a time period T2 between a time at which video data to be included in the second system stream starts to be input to the video buffer and a time at which audio data to be included in the second system stream starts to be input to the audio buffer;

modifying video data to be included in the first system stream and the video data to be included in the second system stream so that a head portion of the video data to be included in the second system stream is transferred to be positioned at an end of the video data to be included in the first system stream, the transferred head portion of the video data having a predetermined length;

modifying audio data to be included in the first system stream and the audio data to be included in the second system stream so that a head portion of the audio data to be included in the second system stream is transferred to be positioned at an end of the audio data to be included in the first system stream so as to make T2 equal to or shorter than T1, the transferred head portion of the audio data having a duration equal to or longer than one audio frame;

constituting the first system stream by interleaving the modified audio data and the modified video data which are to be included in the first system stream;

constituting the second system stream by interleaving the modified audio data and the modified video data which are to be included in the second system stream; and

constituting the bit stream by arranging the first system stream and the second system stream.

8. An optical disk reproduction apparatus comprising:

an optical disk on which a bit stream including a first system stream and a second system stream which are to be successively reproduced in that order is stored, each of the first and second system streams including video data and audio data interleaved with each other;

a reader for reading the bit stream stored on the optical disk;

means for receiving the read bit stream and extracting, from each of the first and second system streams of the received bit stream, the video data and the audio data separately from each other;

a video buffer for temporarily storing the extracted video data;

an audio buffer for temporarily storing the extracted audio data, the audio buffer being capable of storing N audio frames of the audio data; and

a decoder for decoding the video data input from the video buffer and the audio data input from the audio buffer;

wherein the audio data of the first system stream and the audio data of the second system stream are interleaved in such a manner that a time period between a time at which the input of the audio data of the first system stream to the audio buffer is completed and a time at which the audio data of the second system stream starts to be input to the audio buffer is equal to or shorter than a time period T, where T is a sum of a time period spent for outputting one audio frame decoded by the decoder and a time period spent for decoding and outputting the N audio frames stored in the audio buffer.