EP-4736453-A1 - MULTIPLE RESIDUAL BLOCK CODING MODE

Abstract

A video bitstream comprising coded information of a plurality of partial residual blocks of a current block in a current picture is received. Each of the plurality of partial residual blocks indicates a difference between a respective prediction block of the current block and the current block. The plurality of partial residual blocks of the current block is determined based on respective coding parameters. A residual block is determined based on the plurality of partial residual blocks. A prediction block for the current block is determined. The current block is reconstructed based on a combination of the derived residual block and the determined prediction block.

Inventors

• ZHAO, XIN
• ZHAO, LIANG
• GAO, Han
• YE, JING
• LIU, TIANQI
• LIU, SHAN

Assignees

• Tencent America LLC

Dates

Publication Date

20260506

Application Date

20231027

Claims (20)

1. 1. A method of video decoding, the method comprising: receiving a video bitstream comprising coded information of a plurality of partial residual blocks of a current block in a current picture, each of the plurality of partial residual blocks indicating a difference between a respective prediction block of the current block and the current block; determining the plurality of partial residual blocks of the current block based on respective coding parameters; deriving a residual block based on the plurality of partial residual blocks; determining a prediction block for the current block; and reconstructing the current block based on a combination of the derived residual block and the determined prediction block.
2. 2. The method of claim 1, wherein the plurality of partial residual blocks includes (i) a first partial residual block that is determined based on a difference between a first prediction block of the current block and the current block, and (ii) a second partial residual block that is determined based on a difference between a first reconstruction block of the current block and the current block, the first reconstruction block being determined based on the first partial residual block.
3. 3. The method of claim 1, wherein the determining the plurality of partial residual blocks further comprises: entropy decoding the coded information of the plurality of partial residual blocks of the current block to obtain quantized transform coefficients associated with each of the plurality of partial residual blocks based on the respective coding parameters, the respective coding parameters including at least one of a binarization, a coefficient scanning order, and a context model of the respective partial residual block.
4. 4. The method of claim 3, wherein the determining the plurality of partial residual blocks further comprises: dequantizing the quantized transform coefficients associated with each of the plurality of partial residual blocks to obtain transform coefficients associated with the respective partial residual block based on the respective coding parameters, the respective coding parameters including a quantization step size of the respective partial residual block.
5. 5. The method of claim 4, wherein a quantization step size of the quantized transform coefficients associated with at least one of the plurality of partial residual blocks is equal to 1.
6. 6. The method of claim 4, wherein the determining the plurality of partial residual blocks further comprises: inversely transforming the transform coefficients associated with each of the plurality of partial residual blocks to obtain the plurality of partial residual blocks based on the respective coding parameters that include respective transform kernels.
7. 7. The method of claim 4, wherein the determining the plurality of partial residual blocks further comprises: inversely transforming at least one of the plurality of partial residual blocks based on an identity transform.
8. 8. The method of claim 1, wherein: a size of a first partial residual block of the plurality of partial residual blocks is equal to the size of the current block, and a size of a second partial residual block of the plurality of partial residual blocks is smaller than the size of the current block.
9. 9. The method of claim 1 , wherein: at least one of the plurality of partial residual blocks is coded by a lossy coding mode, and at most one of the plurality of partial residual blocks is coded by a lossless coding mode.
10. 10. The method of claim 1 , wherein the coded information further indicates a number of the plurality of partial residual blocks and which of the plurality of partial residual blocks is coded by a lossless coding mode.
11. 11. The method of claim 1, further comprising: determining a reference block for another block in the current picture, the reference block for the other block including reconstruction samples that are determined based on a subset of the plurality of partial residual blocks.
12. 12. The method of claim 1, wherein the reconstructing the current block further comprises: determining a first reconstruction block of the current block based on a first subset of the plurality of partial residual blocks that is coded by a lossy coding mode and the prediction block; and determining a second reconstruction block of the current block based on a second subset of the plurality of partial residual blocks that is coded by a lossless coding mode and the prediction block.
13. 13. The method of claim 1, further comprising: determining a first reference block for a first block in the current picture based on a first subset of the plurality of partial residual blocks and a second reference block for a second block in another picture based on a second subset of the plurality of partial residual blocks, the first subset of the plurality of partial residual blocks being different from the second subset of the plurality of partial residual blocks.
14. 14. An apparatus, comprising: processing circuitry configured to: receive a video bitstream comprising coded information of a plurality of partial residual blocks of a current block in a current picture, each of the plurality of partial residual blocks indicating a difference between a respective prediction block of the current block and the current block; determine the plurality of partial residual blocks of the current block based on respective coding parameters; derive a residual block based on the plurality of partial residual blocks; determine a prediction block for the current block; and reconstruct the current block based on a combination of the derived residual block and the determined prediction block.
15. 15. The apparatus of claim 14, wherein the plurality of partial residual blocks includes (i) a first partial residual block that is determined based on a difference between a first prediction block of the current block and the current block, and (ii) a second partial residual block that is determined based on a difference between a first reconstruction block of the current block and the current block, the first reconstruction block being determined based on the first partial residual block.
16. 16. The apparatus of claim 14, wherein the processing circuitry is configured to: entropy decode the coded information of the plurality of partial residual blocks of the current block to obtain quantized transform coefficients associated with each of the plurality of partial residual blocks based on the respective coding parameters, the respective coding parameters including at least one of a binarization, a coefficient scanning order, and a context model of the respective partial residual block.
17. 17. The apparatus of claim 16, wherein the processing circuitry is configured to: dequantize the quantized transform coefficients associated with each of the plurality of partial residual blocks to obtain transform coefficients associated with the respective partial residual block based on the respective coding parameters, the respective coding parameters including a quantization step size of the respective partial residual block.
18. 18. The apparatus of claim 17, wherein a quantization step size of the quantized transform coefficients associated with at least one of the plurality of partial residual blocks is equal to 1.
19. 19. The apparatus of claim 17, wherein the processing circuitry is configured to: inversely transform the transform coefficients associated with each of the plurality of partial residual blocks to obtain the plurality of partial residual blocks based on the respective coding parameters that include respective transform kernels.
20. 20. The apparatus of claim 17, wherein the processing circuitry is configured to: inversely transform at least one of the plurality of partial residual blocks based on an identity transform.

Description

MULTIPLE RESIDUAL BLOCK CODING MODE INCORPORATION BY REFERENCE [0001] The present application claims the benefit of priority to U.S. Patent Application No. 18/384,308, “MULTIPLE RESIDUAL BLOCK CODING MODE” filed on October 26, 2023, which claims the benefit of priority to U.S. Provisional Application No. 63/524,549, “Multiple Residual Block Coding Mode” filed on June 30, 2023. The disclosures of the prior applications are hereby incorporated by reference in their entirety. TECHNICAL FIELD [0002] The present disclosure describes embodiments generally related to video coding. BACKGROUND [0003] The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. [0004] Image/video compression can help transmit image/video data across different devices, storage and networks with minimal quality degradation. In some examples, video codec technology can compress video based on spatial and temporal redundancy. In an example, a video codec can use techniques referred to as intra prediction that can compress an image based on spatial redundancy. For example, the intra prediction can use reference data from the current picture under reconstruction for sample prediction. In another example, a video codec can use techniques referred to as inter prediction that can compress an image based on temporal redundancy. For example, the inter prediction can predict samples in a current picture from a previously reconstructed picture with motion compensation. The motion compensation can be indicated by a motion vector (MV). SUMMARY [0005] Aspects of the disclosure include methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry. [0006] According to an aspect of the disclosure, a method of video decoding is provided. In the method, a video bitstream comprising coded information of a plurality of partial residual blocks of a current block in a current picture is received. Each of the plurality of partial residual blocks indicates a difference between a respective prediction block of the current block and the current block. The plurality of partial residual blocks of the current block is determined based on respective coding parameters. A residual block is determined based on the plurality of partial residual blocks. A prediction block for the current block is determined. The current block is reconstructed based on a combination of the derived residual block and the determined prediction block. [0007] In an aspect, the plurality of partial residual blocks includes (i) a first partial residual block that is determined based on a difference between a first prediction block of the current block and the current block, and (ii) a second partial residual block that is determined based on a difference between a first reconstruction block of the current block and the current block, where the first reconstruction block is determined based on the first partial residual block. [0008] In an example, the coded information of the plurality of partial residual blocks of the current block is entropy decoded to obtain quantized transform coefficients associated with each of the plurality of partial residual blocks based on the respective coding parameters. The respective coding parameters include at least one of a binarization, a coefficient scanning order, and a context model of the respective partial residual block. [0009] In an example, the quantized transform coefficients associated with each of the plurality of partial residual blocks are dequantized to obtain transform coefficients associated with the respective partial residual block based on the respective coding parameters. The respective coding parameters include a respective quantization step size of the respective partial residual block. [0010] In an example, a quantization step size of the quantized transform coefficients associated with at least one of the plurality of partial residual blocks is equal to 1. [0011] In an example, the transform coefficients associated with each of the plurality of partial residual blocks are inversely transformed to obtain the plurality of partial residual blocks based on the respective coding parameters that include respective transform kernels. [0012] In an example, at least one of the multiple partial residual blocks is inversely transformed based on an identity transform. [0013] In an example, a size of a first partial residual block of the plurality of partial residual blocks is equal to the size of the current block, and a size of a second partial residual block of the plurality of partial residual blocks is smaller than the si