Apparatus and method for partial buffering transmitted data to provide robust error recovery in a lossy transmission environment

• US 6,263,468 B1
• Filed: 07/06/1998
• Issued: 07/17/2001
• Est. Priority Date: 10/23/1997
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Kondo, Tetsujiro, Carrig, James J., Fujimori, Yasuhiro, Ghosal, Sugata
• Primary Examiner(s): Decady, Albert
• Assistant Examiner(s): Chase, Shelly A
• Application Number:
  US09/111,112
• Time in Patent Office: 1,107 Days
• Field of Search: 714/774, 714/776, 714/760, 714/746, 714/701, 348/419.1, 348/420.1, 386/111, 373/240.23, 373/240.27
• US Class Current: 714/774
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 19/85 using pre-processing or post-processing specially adapted for video compression
• CPC Class Codes: H04N 19/88 involving rearrangement of data among different coding units, e.g. shuffling, interleaving, scrambling or permutation of pixel data or permutation of transform coefficient data among different blocks
• CPC Class Codes: H04N 19/89 involving methods or arrangements for detection of transmission errors at the decoder
• CPC Class Codes: H04N 19/895 in combination with error concealment
• CPC Class Codes: H04N 19/98 Adaptive-dynamic-range coding [ADRC]
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 5/21 Circuitry for suppressing or minimising disturbance, e.g. moiré or halo

Abstract

A system and method for buffering a plurality of divisions of a signal prior to transmission of the signal is disclosed. The buffering is configured to prevent error propagation during decoding of the transmitted signal. A set of encoding levels at a transmission rate is selected from a threshold table having a plurality of encoding levels. Each set of encoding levels includes a plurality of ranges configured to select encoding bits. Each division of the signal is encoded using the set of encoding levels. In one embodiment, this is used in the transmission of video signals over a potentially lossy communications channel.

Claims

1. A method of encoding a signal that restricts error propagation during decoding, the method comprising:

dividing the signal into data segments;

storing each of the data segments in at least one buffer;

determining a number of bits available for use as encoding bits based on a desired transmission rate and a length of the at least one buffer used to store the data segment;

selecting a threshold set for the encoding of each of the data segments, the threshold set having a plurality of ranges, each range of the plurality of ranges assigning a different number of encoding bits wherein the number of encoding bits assigned for the encoding of each data segment is not more than the number of bits available; and

encoding the data segments using the threshold set.

2. The method of claim 1, wherein the threshold set is selected such that the encoded data stored within a buffer is maximized.

3. The method of claim 1, wherein the threshold set is selected such that the number of encoding bits assigned for the encoding of each data segment is as close as possible to the number of bits available without exceeding the number of bits available.

4. The method of claim 1, wherein the at least one buffer is of fixed length.

5. The method of claim 4, wherein bits of the fixed length buffer not filled with encoded data are filled with a predetermined bitstream pattern such that the predetermined bitstream pattern delineates the end of the encoded data.

6. A method of decoding data that restricts error propagation, the method comprising:

receiving encoded data in at least one buffer, the encoded data comprising data segments encoded in accordance with a selected threshold set, the threshold set having a plurality of ranges, each range assigning a different number of encoding bits wherein the number of encoding bits assigned is not more than the number of bits available, the number of bits available for use as encoding bits based upon a desired transmission rate and a length of buffer used to store the data segments;

determining if recovery of the encoded data within a buffer has been inhibited; and

decoding the encoded data within the buffer if the recovery of the data has not been inhibited.

7. The method of claim 6, wherein the at least one buffer is of fixed length.

8. A digital processing system comprising a processor configure to encode a signal such that error propagation during decoding is restricted, said processor configured to divide the signal into data segments, store each of the data segments in at least one buffer, determine a number of bits available for use as encoding bits based on a desired transmission rate and a length of the buffer used to store the data segment, select a threshold set for the encoding of each data segment, the threshold set having a plurality of ranges, each range assigning a different number of encoding bits, wherein the number of encoding bits assigned for the encoding of each data segment is not more than the number of bits available, and encode the data segments using the threshold set.

9. The digital processing system of claim 8, wherein the threshold set is selected such that the encoded data stored within a buffer is maximized.

10. The digital processing system of claim 8, wherein the threshold set is selected such that the number of encoding bits assigned for the encoding of each data segment is as close as possible to the number of bits available without exceeding the number of bits available.

11. The digital processing system of claim 8, wherein the at least one buffer is of fixed length.

12. The digital processing system of claim 11, wherein bits of the fixed length buffer not filled with encoded data are filled with a predetermined bitstream pattern such that the predetermined bitstream pattern delineates the end of the encoded data.

13. A digital processing system comprising a processor configure to decode data such that error propagation is restricted, said processor configured to receive encoded data in at least one buffer, the encoded data comprising data segments encoded in accordance with a selected threshold set, the threshold set having a plurality of ranges, each range assigning a different number of encoding bits wherein the number of encoding bits assigned is not more than the number of bits available, the number of bits available for use as encoding bits based upon a desired transmission rate and a length of buffer used to store the data segments, determine if recovery of the encoded data within a buffer has been inhibited, and decode the encoded data within the buffer if the recovery of the data has not been inhibited.

14. The digital processing system of claim 13, wherein the at least one buffer is of fixed length.

15. A computer-readable medium containing executable instructions which, when executed in a processing system, cause the system to perform the steps of encoding a signal that restricts error propagation during decoding, the encoding comprising the steps of:

dividing the signal into data segments;

storing each of the data segments in at least one buffer;

determining a number of bits available for use as encoding bits based on a desired transmission rate and a length of the buffer used to store the data segment;

selecting a threshold set for the encoding of each data segment, the threshold set having a plurality of ranges, each range assigning a different number of encoding bits, wherein the number of encoding bits assigned for the encoding of each data segment is not more than the number of bits available; and

encoding the data segments using the threshold set.

16. The computer-readable medium of claim 15, wherein the threshold set is selected such that the encoded data stored within a buffer is maximized.

17. The computer-readable medium of claim 15, wherein the threshold set is selected such that the number of encoding bits assigned for the encoding of each data segment is as close as possible to the number of bits available without exceeding the number of bits available.

18. The computer-readable medium of claim 15, wherein the at least one buffer is of fixed length.

19. The computer-readable medium of claim 18, wherein bits of the fixed length buffer not filled with encoded data are filled with a predetermined bitstream pattern such that the predetermined bitstream pattern delineates the end of the encoded data.

20. A computer-readable medium containing executable instructions which, when executed in a processing system, cause the system to perform the steps of decoding data that restricts error propagation, the decoding comprising the steps of:

receiving encoded data in at least one buffer, the encoded data comprising data segments encoded in accordance with a selected threshold set, the threshold set having a plurality of ranges, each range assigning a different number of encoding bits wherein the number of encoding bits assigned is not more than the number of bits available, the number of bits available for use as encoding bits based upon a desired transmission rate and a length of buffer used to store the data segments;

determining if recovery of the encoded data within a buffer has been inhibited; and

decoding the encoded data within the buffer if the recovery of the data has not been inhibited.

21. The computer-readable medium of claim 20, wherein the at least one buffer is of fixed length.

22. A system for encoding a signal that restricts error propagation during decoding, the system comprising:

means for dividing the signal into data segments;

means for storing each of the data segments in at least one buffer;

means for determining a number of bits available for use as encoding bits based on a desired transmission rate and the length of the buffer used to store the data segment;

means for selecting a threshold set for the encoding of each data segment, the threshold set having a plurality of ranges, each range assigning a different number of encoding bits, such that the number of encoding bits assigned for the encoding of each data segment is not more than the number of bits available; and

means for encoding the data segments using the threshold set.

23. The system of claim 22, wherein the threshold set is selected such that the encoded data stored within a buffer is maximized.

24. The system of claim 22, wherein the threshold set is selected such that the number of encoding bits assigned for the encoding of each data segment is as close as possible to the number of bits available without exceeding the number of bits available.

25. The system of claim 22, wherein the at least one buffer is of fixed length.

26. The system of claim 25, wherein bits of the fixed length buffer not filled with encoded data are filled with a predetermined bitstream pattern such that the predetermined bitstream pattern delineates the end of the encoded data.

27. A system for decoding data that restricts error propagation, the system comprising:

means for receiving encoded data in at least one buffer

means for determining if recovery of the encoded data within a buffer has been inhibited; and

means for decoding the encoded data within the buffer if the recovery of the data has not been inhibited;

wherein the encoded data comprises data segments encoded in accordance with a selected threshold set, the threshold set having a plurality of ranges, each range assign a different number of encoding bits wherein the number of encoding bits assigned is not more than the number of bits available, the number of bits available for use as encoding bits based upon a desired transmission rate and a length of buffer used to store the data segments.

28. The system of claim 27, wherein the at least one buffer is of fixed length.