Method for coding video and related device

Patent metadata

Field	Value
Publication number	US-11700373-B2
Application number	US-202017129504-A
Country	US
Kind code	B2
Filing date	Dec 21, 2020
Priority date	Jun 29, 2020
Publication date	Jul 11, 2023
Grant date	Jul 11, 2023

Abstract

The present disclosure provides a method and an apparatus for coding a video, a device and a medium. An estimated quantization parameter of a target picture in a target GOP is determined. An inter-picture change degree of the target GOP is determined. A propagation ratio of a target picture block to a reference picture block in the target picture is determined based on the estimated quantization parameter of the target picture and the inter-picture change degree. The video is coded based on the propagation ratio.

First claim

What is claimed is:

1. A computer-implemented method for coding a video, comprising:
determining an estimated quantization parameter of a target picture in a target group of pictures (GOP), wherein the target GOP is associated to the video, the estimated quantization parameter is an average value of actual quantization parameters of the target picture in a previous GOP and the estimated quantization parameter is configured to indicate a number of picture blocks in the target picture for increasing a propagation ratio;
determining an inter-picture change degree of the target GOP based on a number of target pictures included in the target GOP and an intra-picture block ratio of the target GOP, in which the intra-picture block ratio is a ratio of the number of picture blocks for performing intra-picture prediction in the target GOP to the number of picture blocks for performing inter-picture prediction in the target GOP, and the inter-picture change degree is an index to measure a change in the picture content between the pictures of the target GOP;
determining a propagation ratio of a target picture block to a reference picture block in the target picture based on the estimated quantization parameter of the target picture and the inter-picture change degree; and
coding the video based on the propagation ratio;
wherein coding the video comprises:
performing coding unit (CU)-Tree energy propagation based on the propagation ratio to obtain received energy of the target picture block;
converting the received energy into an offset of the quantization parameter of the target picture block by an equation of
QP_offset=(−1)*intensity*log(1+energy/IntraCost), where QP_offset is the offset of the quantization parameter of the target picture block, energy represents the received energy, intensity represents the parameter offset value, IntraCost represents the intra-picture prediction cost value, and −1 indicates the value of QP_offset is negative.

2. The computer-implemented method according to claim 1 , wherein determining the propagation ratio comprises:
determining a dependence degree of the target picture block on the reference picture block in the target picture based on the estimated quantization parameter of the target picture; and
determining the propagation ratio of the target picture block to the reference picture block in the target picture by adjusting a ratio of an inter-picture prediction cost value to an intra-picture prediction cost value based on the dependence degree and the inter-picture change degree.

3. The computer-implemented method according to claim 2 , wherein determining the propagation ratio of the target picture block to the reference picture block in the target picture based on the dependence degree and the inter-picture change degree comprises:
determining an adjustment mode of the propagation ratio based on the dependence degree and the inter-picture change degree; and
adjusting the propagation ratio of the target picture block to the reference picture block in the target picture based on the adjustment mode and a preset adjustment value for adjusting the propagation ratio.

4. The computer-implemented method according to claim 2 , wherein the determining the dependence degree of the target picture block on the reference picture block in the target picture based on the estimated quantization parameter of the target picture comprises:
determining an inter-picture cost threshold based on the estimated quantization parameter of the target picture; and
determining the dependence degree of the target picture block on the reference picture block in the target picture based on an inter-picture prediction cost value of the target picture block and the inter-picture cost threshold.

5. The computer-implemented method according to claim 1 , wherein the coding the video to be coded further comprises:
determining a quantization parameter of the target picture block based on the propagation ratio and a propagation algorithm; and
coding the video based on the quantization parameter of the target picture block.

6. The computer-implemented method according to claim 5 , wherein the determining the quantization parameter of the target picture block based on the propagation ratio and the propagation algorithm comprises:
converting the received energy into the offset of the quantization parameter of the target picture block based on the inter-picture change degree; and
determining the quantization parameter of the target picture block based on the offset of the quantization parameter of the target picture block and the estimated quantization parameter of the target picture comprising the target picture block.

7. The computer-implemented method according to claim 6 , wherein converting the received energy into the offset of the quantization parameter of the target picture block based on the inter-picture change degree comprises:
determining a parameter offset value based on the inter-picture change degree; and
converting the received energy into the offset of the quantization parameter of the target picture block based on the parameter offset value.

8. An electronic device, comprising:
at least one processor; and
a memory, connected in communication with the at least one processor;
wherein, the memory is configured to store instructions executable by the at least one processor, when the instructions are executed by the at least one processor, the at least one processor is configured to:
determine an estimated quantization parameter of a target picture in a target group of pictures (GOP), wherein the target GOP is associated to the video, the estimated quantization parameter is an average value of actual quantization parameters of the target picture in a previous GOP and the estimated quantization parameter is configured to indicate a number of picture blocks in the target picture for increasing a propagation ratio;
determine an inter-picture change degree of the target GOP based on the number of target pictures included in the target GOP and an intra-picture block ratio of the target GOP, in which the intra-picture block ratio is a ratio of the number of picture blocks for performing intra-picture prediction in the target GOP to the number of picture blocks for performing inter-picture prediction in the target GOP, and the inter-picture change degree is an index to measure a change in the picture content between the pictures of the target GOP;
determine a propagation ratio of a target picture block to a reference picture block in the target picture based on the estimated quantization parameter of the target picture and the inter-picture change degree; and
code the video based on the propagation ratio;
wherein coding the video comprises:
performing coding unit (CU)-Tree enemy propagation based on the propagation ratio to obtain received energy of the target picture block;
converting the received energy into an offset of the quantization parameter of the target picture block by an equation of
QP_offset=(−1)*intensity*log(1+energy/IntraCost), where QP_offset is the offset of the quantization parameter of the target picture block, energy represents the received energy, intensity represents the parameter offset value, IntraCost represents the intra-picture prediction cost value, and −1 indicates the value of QP_offset is negative.

9. The electronic device according to claim 8 , wherein the at least one processor is configured to:
determine a dependence degree of the target picture block on the reference picture block in the target picture based on the estimated quantization parameter of the target picture; and
determine the propagation ratio of the target picture block to the reference picture block in the ta

Assignees

• Beijing Baidu Netcom Sci & Tech Co Ltd

Inventors

• Lin Ke
• Ding Wenpeng

Classifications

• H04N19/176

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

• H04N19/177

  the unit being a group of pictures [GOP] · CPC title

• H04N19/136

  Incoming video signal characteristics or properties · CPC title

• H04N19/124 Primary

  Quantisation · CPC title

• H04N19/115 Primary

  Selection of the code volume for a coding unit prior to coding · CPC title