Cross-component sample adaptive offset

Patent metadata

Field	Value
Publication number	US-12501063-B2
Application number	US-202418619448-A
Country	US
Kind code	B2
Filing date	Mar 28, 2024
Priority date	Nov 19, 2021
Publication date	Dec 16, 2025
Grant date	Dec 16, 2025

Abstract

Method and devices are provided for video coding. In the method, a decoder obtains a cross-component sample adaptive offset (CCSAO) quantization associated with an offset quantization control syntax and a quantization step size that are predefined or indicated by an encoder at at least one level. Furthermore, the decoder obtains a CCSAO based on the CCSAO quantization and adds the CCSAO to a reconstructed sample for prediction.

First claim

What is claimed is:

1 . A method for video decoding, comprising:
obtaining, by a decoder, a cross-component sample adaptive offset (CCSAO) quantization associated with an offset quantization control syntax and a quantization step size that are predefined or indicated by an encoder at at least one level; obtaining, by the decoder, a CCSAO based on the CCSAO quantization; and adding, by the decoder, the CCSAO to a reconstructed sample for prediction.

2 . The method of claim 1 , wherein the at least one level comprises at least one of following levels: a Sequence Parameter Set (SPS) level, an Adaption Parameter Set (APS) level, a Picture Parameter Set (PPS) level, a Picture Header (PH) level, a Sequence Header (SH) level, a Region level, a Coding Tree Unit (CTU) level, a Subblock level, or a Sample level.

3 . The method of claim 1 , further comprising:
obtaining, by the decoder, the quantization step size that is predefined according to a bit-depth or a resolution.

4 . The method of claim 1 , further comprising:
obtaining, by the decoder, the offset quantization control syntax and the quantization step size stored in an Adaption Parameter Set (APS).

5 . The method of claim 1 , further comprising:
receiving, by the decoder, a range of supported quantization step sizes in a sequence, wherein the range of supported quantization step sizes are predefined or signaled at the at least one level.

6 . The method of claim 1 , further comprising:
obtaining, by the decoder, an offset binarization method that is determined according to the quantization step size, wherein the offset binarization method is predefined or signaled at the at least one level.

7 . The method of claim 6 , wherein the CCSAO applies to a category that is classified based on a plurality of collocated samples that are respectively selected for a plurality of components of a reconstructed sample.

8 . The method of claim 7 , wherein the plurality of components comprise a first component and a second component, and the first component and the second component have different offset quantization control syntax values, different quantization step sizes, or different offset binarization methods.

9 . The method of claim 8 , wherein the first component comprises one of following components: a Y component, a U component, or a V component, the second component comprises one of following components: the Y component, the U component, or the V component, and the first component is different from the second component, and
wherein the plurality of components are configured to classify the first component or the second component.

10 . The method of claim 7 , wherein the plurality of components comprise a first component and a second component, and the first component and the second component have a same offset quantization control syntax value, a same quantization step size, and a same offset binarization method.

11 . The method of claim 10 , wherein the first component comprises a U component, and the second component comprises a V component.

12 . The method of claim 6 , further comprising:
obtaining, by the decoder, different offset quantization binarization methods that are predefined for different quantization step sizes.

13 . The method of claim 12 , wherein the different offset quantization binarization methods comprise exponential-Golomb (EGk) coding, Truncated Unary (TU) coding, and fixed-length coding (FLC).

14 . The method of claim 12 , wherein the different quantization step sizes are predefined using different exponential-Golomb (EGk) orders.

15 . An apparatus for video decoding, comprising:
one or more processors; and a memory coupled to the one or more processors and configured to store instructions executable by the one or more processors, wherein the one or more processors, upon execution of the instructions, are configured to perform a method for video decoding, the method comprising: obtaining a cross-component sample adaptive offset (CCSAO) quantization associated with an offset quantization control syntax and a quantization step size that are predefined or indicated by an encoder at at least one level; obtaining a CCSAO based on the CCSAO quantization; and adding the CCSAO to a reconstructed sample for prediction.

16 . A method for video encoding, comprising:
predefining or signaling, by an encoder, a quantization step size for a cross-component sample adaptive offset (CCSAO) quantization at at least one level; determining, by the encoder, the CCSAO quantization, wherein the CCSAO quantization is associated with an offset quantization control syntax and the quantization step size; and encoding, by the encoder, the CCSAO quantization in a bitstream.

17 . The method of claim 16 , further comprising:
signaling, by the encoder, the quantization step size that is predefined according to a bit-depth or a resolution.

18 . The method of claim 16 , further comprising:
signaling, by the encoder, a range of supported quantization step sizes in a sequence, wherein the range of supported quantization step sizes are predefined or signaled at the at least one level.

19 . The method of claim 16 , further comprising:
signaling, by the encoder, an offset binarization method that is determined according to the quantization step size, wherein the offset binarization method is predefined or signaled at the at least one level.

20 . A method for storing a bitstream, comprising:
performing the method for video encoding according to claim 16 to generate a bitstream; and storing the bitstream.

Assignees

• Beijing Dajia Internet Information Tech Co Ltd

Inventors

• Kuo Che-Wei
• Xiu Xiaoyu
• Chen Wei
• Wang Xianglin
• Chen Yi-Wen
• Jhu Hong-Jheng
• Yan Ning
• Yu Bing

Classifications

• H04N19/82

  involving filtering within a prediction loop · CPC title

• H04N19/124 Primary

  Quantisation · CPC title

• H04N19/117

  Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) · CPC title

• H04N19/186

  the unit being a colour or a chrominance component · CPC title

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title