System updating accumulated statistics coding variable values after multiple encodings

• US 7,573,405 B2
• Filed: 12/27/2007
• Issued: 08/11/2009
• Est. Priority Date: 12/29/2006
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Shima, Masato
• Primary Examiner(s): YOUNG, BRIAN K
• Application Number:
  US11/964,890
• Publication Number:
  US 20080165036A1
• Time in Patent Office: 593 Days
• Field of Search: 341/107, 341/106, 341/50, 341/51, 382/244, 382/245, 382/246, 382/247
• US Class Current: 341/51
• CPC Class Codes: H03M 7/40 Conversion to or from variable length codes, e.g. Shannon-Fano code, Huffman code, Morse code
• CPC Class Codes: H03M 7/4006 Conversion to or from arithmetic code
• 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 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/34 Scalability techniques involving progressive bit-plane based encoding of the enhancement layer, e.g. fine granular scalability [FGS]
• 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 19/61 in combination with predictive coding

Abstract

A system for, and method of, entropy coding. In one embodiment, the system includes: (1) a memory configured to contained initialized accumulated statistics coding variable values and (2) a processor configured to employ the initialized accumulated statistics coding variable values to context-adaptive encode multiple symbols until an accumulated statistics update condition occurs and updating and store the accumulated statistics coding variable values in the memory only upon occurrence of the accumulated statistics update condition.

Claims

1. A system, comprising:

A. a memory configured to contain initialized accumulated statistics coding variable values; and

B. a processor configured;

i. to employ said initialized accumulated statistics coding variable values to context-adaptive encode multiple symbols until an accumulated statistics update condition occurs, and

ii. to update and store said accumulated statistics coding variable values in said memory only upon occurrence of said accumulated statistics update condition.

2. The system as recited in claim 1 wherein said accumulated statistics update condition is selected from the group consisting of:

completion of a coding of a syntax element,

completion of a coding of multiple syntax elements,

completion of a coding of a macroblock,

completion of a coding of multiple macroblocks, and

completion of a coding pass.

3. The system as recited in claim 1 wherein said processor is further configured to repeat said context-adaptive encoding and said updating until all symbols to be encoded are encoded.

4. The system as recited in claim 1 wherein said initialized accumulated statistics coding variable values are initialized in accordance with one selected from the group consisting of:

context-adaptive variable-length coding (CAVLC),

context-based adaptive binary arithmetic coding (CABAC), arithmetic entropy coding, and

adaptive variable-length coding (VLC).

5. The system as recited in claim 1 wherein said memory contains a plurality of variable-length coding (VLC) tables and said processor is further configured to retrieve codewords from a selected one of said plurality.

6. The system as recited in claim 1 wherein said updating is used either alone or together with a complexity reduction method for entropy coding.

7. A system, comprising:

A. a memory configured to contain plural, initialized accumulated statistics coding variable-length coding (VLC) tables; and

B. a processor configured;

i. to retrieve codewords from a selected one of the plural, initialized accumulated statistics coding variable-length coding (VLC) tables to context-adaptive encode multiple symbols until an accumulated statistics update condition occurs, and

ii. to update and store said accumulated statistics coding variable values in said memory only upon occurrence of said accumulated statistics update condition.