Token-based adaptive video processing arrangement

• US 5,835,792 A
• Filed: 06/07/1995
• Issued: 11/10/1998
• Est. Priority Date: 06/24/1993
• Status: Expired due to Term

• Current Assignee: Talon Research LLC
• Original Assignee: Discovision Associates (Pioneer Corporation)
• Inventors: Jones, Anthony Mark, Smith, Colin, Barnes, David Andrew, Patterson, Donald William, Barnes, Mark, Claydon, Anthony Peter John, Wise, Adrian P., Robbins, William P., Birch, Nicholas, Kuligowski, Andrew Peter, Finch, Helen Rosemary, Sotheran, Martin William, Dewar, Kevin D.
• Primary Examiner(s): DINH, DUNG C
• Application Number:
  US08/487,134
• Time in Patent Office: 1,252 Days
• Field of Search: 395/800, 395/506, 395/500, 395/800.01, 395/800.56, 395/888, 364/736, 391/81, 391/105, 391/145, 391/184, 348/512, 348/500, 348/501, 345/418, 345/352, 345/428, 345/501, 345/506
• US Class Current: 710/68
• CPC Class Codes: G06F 12/0207 with multidimensional access, e.g. row/column, matrix
• CPC Class Codes: G06F 12/04 Addressing variable-length words or parts of words
• CPC Class Codes: G06F 13/16 for access to memory bus G06F13/28 takes precedence
• CPC Class Codes: G06F 13/28 using burst mode transfer, e.g. direct memory access DMA, cycle steal G06F13/32 takes precedence
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/42 characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/423 characterised by memory arrangements H04N19/433 takes precedence
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/91 Entropy coding, e.g. variable length coding [VLC] or arithmetic coding
• CPC Class Codes: H04N 21/4305 Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer

Abstract

An MPEG video decompression method and apparatus utilizing a plurality of stages interconnected by a two-wire interface arranged as a pipeline processing machine. Control tokens and DATA Tokens pass over the single two-wire interface for carrying both control and data in token format. A token decode circuit is positioned in certain of the stages for recognizing certain of the tokens as control tokens pertinent to that stage and for passing unrecognized control tokens along the pipeline. Reconfiguration processing circuits are positioned in selected stages and are responsive to a recognized control token for reconfiguring such stage to handle an identified DATA Token. A wide variety of unique supporting subsystem circuitry and processing techniques are disclosed for implementing the system, including memory addressing, transforming data using a common processing block, time synchronization, asynchronous swing buffering, storing of video information, a parallel Huffman decoder, and the like.

Claims

1. In a pipelined video decoder and decompression system having an input, an output and a plurality of processing stages between the input and the output:

a first interactive metamorphic interfacing token, defining a universal adaptation unit for control and/or data functions among said processing stages, wherein said first interactive interfacing token is a SEQUENCE_-- DISPLAY_-- EXTN token for indicating sequence display extension identification; and

a first token generator, responsive to an MPEG2 extension start code in an input stream of encoded data for generating said first interactive interfacing token, wherein said first interactive interfacing token is serially transmitted through said processing stages;

wherein said processing stages comprise a temporal decoder responsive to tokens generated by said first token generator, and a video formatter responsive to said temporal decoder, said video formatter having no more than three frame stores and comprising;

a first frame store for storage of a first video frame;

a second frame store for storage of a second video frame; and

a third frame store having defined therein a first field store and a second field store therein, a third video frame being stored in a selected one of said first field store and said second field store;

wherein after a portion of said third video frame has been read from said selected field store, a portion of a fourth video frame is written therein.

2. The system according to claim 1, wherein said MPEG2 extension start code is a sequence display extension ID code.

3. The system according to claim 1, wherein said first token generator operates on byte aligned data.

4. The system according to claim 1, further comprising a microprocessor interface operatively associated with said processing stages, wherein said microprocessor interface is responsive to a signal IN_-- TOKEN without detection of an end marker of said first interactive interfacing token.

5. The system according to claim 1, wherein said first token generator detects overlapping start codes,

whereby a first overlapping start code is ignored and a second overlapping start code is used to generate start code tokens.

6. The system according to claim 1, further comprising a second token generator for a second interactive interfacing token, wherein said second interactive interfacing token comprises a TIME_-- STAMP token having time stamp information therein, said TIME_-- STAMP token being inserted into a stream of tokens responsive to a token generated by said first token generator.

7. The system according to claim 1, wherein said first video frame is an MPEG I frame, said second video frame is an MPEG P frame, and said third video frame and said fourth video frames are MPEG B frames.

8. The system according to claim 1, wherein portions of said first field store and said second field store are FIFOs.

9. For use with a video decoder and decompression system having a plurality of pipelined processing stages, comprising;

a universal adaptation unit in the form of an interactive interfacing token for control and/or data functions among said processing stages,

wherein said interactive interfacing token comprises a QUANT_-- MATRIX_-- EXTN token for indicating quant matrix extension identification and a TIME_-- STAMP token having time stamp information therein; and

a first token generator, responsive to an MPEG2 extension start code in an input stream of encoded data for generating said QUANT_-- MATRIX_-- EXTN token and said TIME_-- STAMP token, wherein said QUANT_-- MATRIX_-- EXTN token and said TIME_-- STAMP token are serially transmitted through said processing stages;

wherein said processing stages comprise a temporal decoder responsive to said QUANT_-- MATRIX_-- EXTN token and said TIME_-- STAMP tokens, said temporal decoder further comprising;

a demultiplexer, accepting a stream of multiplexed data, and outputting a plurality of elementary streams of data, each said elementary stream comprising a series of access units and having a series of time stamps associated therewith;

a clock reference for initializing system time in a first circuit;

a first time counter in communication with said clock reference for keeping system time in a first circuit; and

a second time counter initialized by said clock reference in a second circuit synchronized with said first time counter, for keeping a local copy of said system time and for determining the presentation timing error between said local copy of system time and said system time by comparing said time stamp to said second time counter.

10. The system according to claim 9, wherein said MPEG2 extension start code is a quant matrix extension ID code.

11. The system according to claim 9, wherein said first token generator operates on byte aligned data.

12. The system according to claim 9, further comprising a microprocessor interface operatively associated with said processing stages, wherein said microprocessor interface is responsive to a signal IN_-- TOKEN without detection of an end marker of said first interactive interfacing token.

13. The system according to claim 9, wherein said first token generator detects overlapping start codes,

whereby a first overlapping start code is ignored and a second overlapping start code is used to generate start code tokens.

14. The apparatus according to claim 9, wherein said time stamps are presentation time stamps.

15. The apparatus according to claim 9, wherein said time stamps are decode time stamps.