Method and apparatus for storage or relocation of defined positions in a data stream

• US 7,664,105 B2
• Filed: 11/15/2004
• Issued: 02/16/2010
• Est. Priority Date: 11/25/2003
• Status: Expired due to Fees

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Hubler, Friedemann
• Primary Examiner(s): Ahmed; Salman
• Application Number:
  US10/988,803
• Publication Number:
  US 20050122974A1
• Time in Patent Office: 1,919 Days
• Field of Search: 370/395.4, 370/395.43, 370/395.41, 370/310, 370/338, 370/235, 370/310.1, 370/389, 370/382, 370/392, 370/390, 370/241
• US Class Current: 370/389
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783
• CPC Class Codes: G11B 27/329 on a disc [VTOC]

Abstract

In packet-oriented data streams, structural information which is needed, for example, for searching or for forwarding or reversing is contained only in specific packets. According to the invention, while a data stream is being stored, an information file is produced which contains references to the starts of all those packets which contain this information. The information file contains data blocks, and each data block identifies the position of a data packet with structural information, as well as the distance to the next or previous such data packet, and additional information relating to the respective data packet.

Claims

1. A method for scanning a first digital data stream of time-sensitive video or audio data being composed of data packets of a first type, the data packets of the first type being packed into data packets of a second type forming a second digital data stream, wherein the data packets of the first type have individual different sizes and are larger than the data packets of the second type, and wherein the data packets of the second type have constant size, the method comprising steps of:

reading, by a device for reading digital video or audio data, or receiving, by a device for storing or recording digital video or audio data, the second digital data stream;

reading or receiving an information file (I) containing navigation information;

determining the start position of a first data packet of the first type within the second data stream;

retrieving from the information file start positions of the data packets of the first type and additional information relating to the data packets of the first type, wherein the start position of a particular one of the data packets of the first type is relative to the start position of the next or previous data packet of the first type within said second data stream and comprises at least a number of data packets of the second type or a number of bytes, and wherein the additional information relating to a data packet of the first type comprises a time code corresponding to said particular data packet of the first type;

controlling a device to scan the first data stream, based on said start position of the first data packet of the first type and on said retrieved start positions; and

scanning the first data stream, wherein data packets of the second type or bytes within a data packet of the second type are skipped according to said retrieved number of data packets or number of bytes.

2. A method according to claim 1, wherein the second data stream and the information file are recorded and said scanning comprises forwarding and reversing between the data packets of the first type.

3. A method according to claim 1, wherein said scanning starts from the beginning of the second data stream and is performed between successive data packets of the first type.

4. A method according to claim 1, wherein a position pointer points at the start of a data packet of the first type, and said scanning comprises moving the position pointer among starts of successive data packets of the first type according to said number of data packets of the second type or said number of bytes.

5. A method according to claim 1, wherein the data packets of the first type include time stamps, and wherein said time code is calculated from the time stamps of a plurality of data packets of the first type.

6. A method according to claim 1, wherein said scanning is performed according to commands for forwarding and reversing.

7. A method according to claim 6, wherein a position pointer points at the start of a current data packet of the first type, further comprising the step of displaying the time code of the current data packet of the first type on a display.

8. A method according to claim 1, wherein further data packets of the second type forming said second data stream comprise parts of one or more other data streams being composed of data packets of the first type, and wherein the data packets of the first type are associated to their respective data stream according to a stream identifier which they comprise, and wherein said information file refers only to start positions of data packets of first data stream.

9. An apparatus for scanning a first digital data stream of time-sensitive video or audio data being composed of data packets of a first type, the data packets of the first type being packed into data packets of a second type forming a second digital data stream, wherein the data packets of the first type have individual different sizes and are larger than the data packets of the second type, and wherein the data packets of the second type have constant size, the apparatus comprising:

means for reading, by a device for reading digital video or audio data, or receiving, by a device for storing or recording digital video or audio data, the second digital data stream;

means for reading or receiving an information file containing navigation information;

means for determining the start position of a first data packet of the first type within the second data stream;

means for retrieving from the information file start positions of the data packets of the first type and additional information relating to the data packets of the first type, wherein the start position of a particular one of the data packets of the first type is relative to the start position of the next or previous data packet of the first type within said second data stream and comprises at least a number of data packets of the second type or a number of bytes, and wherein the additional information relating to a data packet of the first type comprises a time code corresponding to said particular data packet of the first type;

means for controlling a device to scan the first data stream; and

means for scanning the first data stream based on said start position of the first data packet of the first type and on said retrieved start positions, wherein data packets of the second type or bytes within a data packet of the second type are skipped according to said retrieved number of data packets or number of bytes.

10. An apparatus according to claim 9, wherein the second data stream and the information file are recorded and said means for scanning performs forwarding and reversing between the data packets of the first type.

11. An apparatus according to claim 9, wherein said means for scanning performs a scanning operation between successive data packets of the first type, starting from the beginning of the second data stream.

12. An apparatus according to claim 9, further comprising a position pointer, wherein the position pointer points at the start of a data packet of the first type, and said means for scanning moves the position pointer among staffs of successive data packets of the first type according to said number of data packets of the second type or said number of bytes.

13. An apparatus according to claim 9, wherein the data packets of the first type include time stamps, further comprising means for calculating said time code from the time stamps of a plurality of data packets of the first type.

14. An apparatus according to claim 9, further comprising means for receiving forward and reverse commands, wherein said means for scanning operates according to the forward and reverse commands.

15. An apparatus according to claim 14, wherein a position pointer points at the start of a current data packet of the first type, further comprising means for displaying the time code of the current second data packet on a display module.

16. An apparatus according to claim 9, wherein further data packets of the second type forming said second data stream comprise parts of one or more other data streams being composed of data packets of the first type, and wherein the data packets of the first type are associated to their respective data stream according to a stream identifier which they comprise, and wherein said information file refers only to start positions of data packets of first data stream.