Data decoding method and apparatus, and data coding method and apparatus

Patent metadata

Field	Value
Publication number	US-11949853-B2
Application number	US-202117470636-A
Country	US
Kind code	B2
Filing date	Sep 9, 2021
Priority date	Aug 26, 2019
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

A data decoding method, performed by a computer device, is provided. The data decoding method includes obtaining coded data corresponding to a current to-be-decoded unit, obtaining a coding mode restriction type corresponding to the current to-be-decoded unit by decoding the coded data, determining a candidate coding mode set corresponding to the current to-be-decoded unit according to the coding mode restriction type, the candidate coding mode set comprising a block copy intra-frame coding mode, selecting a target coding mode from the candidate coding mode set, and decoding the current to-be-decoded unit according to the target coding mode, thereby obtaining corresponding decoded data.

First claim

What is claimed is:

1. A data decoding method, performed by a computer device, the data decoding method comprising:
obtaining coded data corresponding to a current to-be-decoded unit;
obtaining a syntax indicating a coding mode restriction type corresponding to the current to-be-decoded unit by decoding the coded data, the coding mode restriction type indicating which coding mode of the current to-be-decoded unit that decoding of the current to-be-decoded unit is restricted to;
determining a candidate coding mode set corresponding to the current to-be-decoded unit according to the coding mode restriction type, the candidate coding mode set comprising a block copy intra-frame coding mode;
selecting a target coding mode from the candidate coding mode set; and
decoding the current to-be-decoded unit according to the target coding mode, thereby obtaining corresponding decoded data.

2. The data decoding method of claim 1 , wherein the selecting the target coding mode from the candidate coding mode set comprises:
obtaining coding mode flag bit information corresponding to the current to-be-decoded unit by decoding the coded data, the coding mode flag bit information indicating which coding mode that decoding of the current to-be-decoded unit is restricted to; and
determining the target coding mode corresponding to the current to-be-decoded unit according to the coding mode restriction type and the coding mode flag bit information.

3. The data decoding method of claim 2 , wherein the determining the target coding mode corresponding to the current to-be-decoded unit according to the coding mode restriction type and the coding mode flag bit information comprises:
determining, according to the coding mode restriction type, that the coding mode flag bit information related to the block copy intra-frame coding mode needs to be read; and
determining, based on determining that the coding mode flag bit information needs to be read, the candidate coding mode set according to the coding mode flag bit information after the coding mode flag bit information related to the block copy intra-frame coding mode is read.

4. The data decoding method of claim 2 , wherein the syntax indicates that the coding mode restriction type is an intra-frame coding mode restriction type that indicates that the coding mode for the decoding the current to-be-decoded unit is restricted to an intra-frame coding mode, and the selecting the target coding mode corresponding to the current to-be-decoded unit according to the coding mode restriction type and the coding mode flag bit information comprises:
determining the target coding mode as a common intra-frame coding mode based on a value corresponding to the coding mode flag bit information being a first flag bit value; or
determining the target coding mode as the block copy intra-frame coding mode based on a value corresponding to the coding mode flag bit information being a second flag bit value.

5. The data decoding method of claim 4 , wherein the coding mode flag bit information is ibc_flag or flag bit information related to ibc_flag.

6. The data decoding method of claim 4 , wherein flag bit information of the block copy intra-frame coding mode is ibc_flag, and
wherein, based on the coding mode in the intra-frame coding mode restriction type being the common intra-frame coding mode, ibc_flag is set to 0; or based on the coding mode in the intra-frame coding mode restriction type being the block copy intra-frame coding mode, ibc_flag is set to 1.

7. The data decoding method of claim 2 , wherein the coding mode restriction type is an inter-frame coding mode restriction type that indicates that the coding mode for the decoding the current to-be-decoded unit is restricted to an inter-frame coding mode, and the determining the target coding mode corresponding to the current to-be-decoded unit according to the coding mode restriction type and the coding mode flag bit information comprises:
determining the target coding mode as a common inter-frame coding mode based on a value corresponding to the coding mode flag bit information being a first flag bit value; or
determining the target coding mode as the block copy intra-frame coding mode based on a value corresponding to the coding mode flag bit information being a second flag bit value.

8. The data decoding method of claim 1 , wherein the syntax in the coded data is root_cu_mode=‘PRED_Inter_only’, and the syntax indicates that the coding mode restriction type is an inter-frame coding mode restriction type that indicates that the coding mode for the decoding the current to-be-decoded unit is restricted to an inter-frame coding mode, and
the target coding mode is a common inter-frame coding mode.

9. The data decoding method of claim 1 , wherein the syntax in the coded data indicates that the coding mode restriction type is an inter-frame coding mode restriction type that indicates that the coding mode for the decoding the current to-be-decoded unit is restricted to an inter-frame coding mode,
the target coding mode is a common inter-frame coding mode, and
an additional syntax in the coded data is skip_flag.

10. The data decoding method of claim 1 , wherein the coding mode restriction type is a block copy intra-frame coding mode restriction type that indicates that a coding mode for the decoding the current to-be-decoded unit is restricted to the block copy intra-frame coding mode, and
wherein the selecting the target coding mode from the candidate coding mode set comprises:
determining the target coding mode corresponding to the current to-be-decoded unit as the block copy intra-frame coding mode based on the block copy intra-frame coding mode restriction type.

11. The data decoding method of claim 10 , wherein
the syntax in the coded data is root_cu_mode=‘PRED_Ibc_only’, and
the determining the target coding mode corresponding to the current to-be-decoded unit as the block copy intra-frame coding mode comprises determining the target coding mode based on the syntax in the coded data, and without transmitting and decoding flag bit information of the block copy intra-frame coding mode.

12. The data decoding method of claim 1 , further comprising:
determining the target coding mode corresponding to the current to-be-decoded unit as a common intra-frame coding mode based on the coding mode restriction type obtained through decoding being a common intra-frame coding mode restriction type that indicates that the coding mode for the decoding the current to-be-decoded unit is restricted to the common intra-frame coding mode.

13. The data decoding method of claim 1 , further comprising:
determining the target coding mode corresponding to the current to-be-decoded unit as a common inter-frame coding mode based on the coding mode restriction type obtained through decoding being a common inter-frame coding mode restriction type that indicates that the coding mode for the decoding the current to-be-decoded unit is restricted to the common inter-frame coding mode.

14. The data decoding method of claim 1 , wherein the decoding the current to-be-decoded unit according to the target coding mode to obtain corresponding decoded data comprises:
obtaining, from the coded data based on the target coding mode being the block copy intra-frame coding mode, block vector information and residual information that correspond to the current to-be-decoded unit;
determining prediction information corresponding to the current to-be-decoded unit according to the block vector information; and
obtaining a decoded image unit corresponding to the current to-be-decoded unit according to th

Assignees

• Tencent Tech Shenzhen Company Ltd

Inventors

• Li Yiming
• Xu Xiaozhong
• Hu Ye
• Liu Shan
• Chen Zhenzhong

Classifications

• H04N19/107 Primary

  between spatial and temporal predictive coding, e.g. picture refresh · CPC title

• H04N19/159

  Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction · CPC title

• H04N19/176

  the region being a block, e.g. a macroblock · CPC title

• H04N19/46

  Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence) · CPC title

• H04N19/70

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