Size based transform unit context derivation

Patent metadata

Field	Value
Publication number	US-12206897-B2
Application number	US-202217898283-A
Country	US
Kind code	B2
Filing date	Aug 29, 2022
Priority date	Aug 15, 2012
Publication date	Jan 21, 2025
Grant date	Jan 21, 2025

Abstract

Systems, apparatus, articles, and methods are described including operations for size based transform unit context derivation. In an example encoder, first circuitry is to encode video input data into a bitstream according to a bitstream syntax, wherein the video input data includes one or more pictures, the one or more pictures are partitioned into one or more coding tree blocks, the one or more coding tree blocks are partitioned into slices including one or more coding tree blocks, the one or more coding tree blocks include one or more transform blocks according to a transform tree including a split_transform_flag indicative of the split of a given coding block into corresponding one or more transform blocks, the split_transform_flag is coded using CABAC, and a context index associated with the CABAC coding of the split_transform_flag is based on a value. Second circuitry of the encoder is to output the bitstream.

First claim

What is claimed:

1. An encoder, comprising:
first circuitry to:
encode video input data into a bitstream according to a bitstream syntax;
wherein the video input data includes one or more pictures;
wherein the one or more pictures are partitioned into one or more coding tree blocks;
wherein the one or more coding tree blocks are partitioned into slices including one or more coding tree blocks;
wherein the one or more coding tree blocks include one or more transform blocks according to a transform tree including a split_transform_flag;
wherein the split_transform_flag is indicative of the split of a given coding block into corresponding one or more transform blocks;
wherein the split_transform_flag is coded using context adaptive binary arithmetic coding (CABAC);
wherein a context index associated with the CABAC coding of the split_transform_flag is based on a value (5−log 2 (TU_size)) where TU_size represents a size of the corresponding one or more transform blocks; and

second circuitry to output the bitstream.

2. The encoder of claim 1 , wherein the context index is initialized based on an initialization table that includes values including 92,122,124, 138, 153, 167, and 224.

3. The encoder of claim 1 , wherein TU_size is equal to 32×32, 16×16, or 8×8.

4. The encoder of claim 1 , wherein the first circuitry is further to perform a motion prediction on the video input data.

5. The encoder of claim 4 , wherein the first circuitry is further to transform an output of the motion prediction.

6. The encoder of claim 5 , wherein the first circuitry is further to quantize an output of the transforming.

7. The encoder of claim 1 , wherein the bitstream syntax defines that the size of the corresponding one or more transform blocks is at least equal to 4×4.

8. The encoder of claim 1 , wherein the bitstream syntax defines that a largest size of the one or more coding blocks is 64×64.

9. The encoder of claim 1 , wherein the context index includes one of three potential values.

10. A non-transitory computer readable medium comprising instructions that, when executed, cause logic circuitry to at least:
encode video input data into a bitstream according to a bitstream syntax,
wherein the video input data includes one or more images,
wherein the one or more images are partitioned into one or more coding tree blocks,
wherein the one or more coding tree blocks are partitioned into slices including one or more coding tree blocks,
wherein the one or more coding tree blocks include one or more transform blocks according to a transform tree including a split_transform_flag,
wherein the split_transform_flag is indicative of the split of a given coding block into corresponding one or more transform blocks,
wherein the split_transform_flag is coded using context adaptive binary arithmetic coding (CABAC),
wherein a context index associated with the CABAC coding of the split_transform_flag is based on a value (5−log 2 (TU_size)) where TU_size represents a size of the corresponding one or more transform blocks; and

output the bitstream.

11. The non-transitory computer readable medium of claim 10 , wherein the context index is initialized based on an initialization table that includes values including 92, 122, 124, 138, 153, 167, and 224.

12. The non-transitory computer readable medium of claim 10 , wherein TU_size is equal to 32×32, 16×16, or 8×8.

13. The non-transitory computer readable medium of claim 10 , wherein the instructions, when executed, cause the logic circuitry to perform a motion prediction on the video input data.

14. The non-transitory computer readable medium of claim 13 , wherein the instructions, when executed, cause the logic circuitry to transform an output of the motion prediction.

15. The non-transitory computer readable medium of claim 14 , wherein the instructions, when executed, cause the logic circuitry to quantize an output of the transforming.

16. The non-transitory computer readable medium of claim 10 , wherein the bitstream syntax defines that the size of the corresponding one or more transform blocks is at least equal to 4×4.

17. The non-transitory computer readable medium of claim 10 , wherein the bitstream syntax defines that a largest size of the one or more coding blocks is 64×64.

18. The non-transitory computer readable medium of claim 10 , wherein the context index includes one of three potential values.

19. A method for processing a bitstream, the method comprising:
encoding, by executing an instruction with at least one logic circuit, video input data into a bitstream according to a bitstream syntax,
wherein the video input data includes one or more pictures,
wherein the one or more pictures are partitioned into one or more coding tree blocks,
wherein the one or more coding tree blocks are partitioned into slices including one or more coding tree blocks,
wherein the one or more coding tree blocks include one or more transform blocks according to a transform tree including a split_transform_flag,
wherein the split_transform_flag is indicative of the split of a given coding block into corresponding one or more transform blocks,
wherein the split_transform_flag is coded using context adaptive binary arithmetic coding (CABAC),
wherein a context index associated with the CABAC coding of the split_transform_flag is based on a value (5−log 2 (TU_size)) where TU_size represents a size of the corresponding one or more transform blocks; and

outputting the bitstream.

20. The method of claim 19 , wherein the context index is initialized based on an initialization table that includes values including 92,122,124, 138, 153, 167, and 224.

Assignees

• Intel Corp

Inventors

• Zhang Wenhao
• Chiu Yi-Jen
• Kapsenberg Pieter
• Xu Lidong
• Han Yu
• Deng Zhipin Apple
• Cai Xiaoxia

Classifications

• H04N19/122 Primary

  Selection of transform size, e.g. 8x8 or 2x4x8 DCT; Selection of sub-band transforms of varying structure or type · CPC title

• H04N19/91

  Entropy coding, e.g. variable length coding [VLC] or arithmetic coding · CPC title

• H04N19/96

  Tree coding, e.g. quad-tree coding · CPC title

• H04N19/61

  in combination with predictive coding · CPC title

• H04N19/13

  Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC] · CPC title