Granted Patent B2

US 12,641,272 · App. 18/241,011 · Granted May 26, 2026

Inventors: Lien-Fei Chen (Hsinchu, TW); Xiaozhong Xu (State College, PA); Xin Zhao (Santa Clara, CA); Roman Chernyak (Palo Alto, CA); Shan Liu (San Jose, CA)

Assignee: Tencent America LLC

H04N19/50H04N19/105H04N19/129H04N19/132H04N19/172H04N19/176H04N19/70

Abstract

Claims (57)

1 . A method of video decoding, comprising:

receiving coded information of a current block in a current picture from a coded video bitstream, the coded information being indicative of applying a local illumination compensation (LIC) on the current block according to a reference block in a reference picture;

decoding a flag from the coded information;

constructing a parameter set list for the LIC, the parameter set list comprising a plurality of parameter sets for the LIC, the constructing including scanning spatial non adjacent blocks relative to the current block to construct the parameter set list when the flag indicates that parameter set information from the spatial non adjacent blocks is used, the plurality of parameter sets for the LIC including a parameter set used to perform the LIC on one of the spatial non adjacent blocks;

obtaining a LIC index from the coded video bitstream, the LIC index having a value indicative of a parameter set in the parameter set list for the LIC;

determining a selected parameter set from the parameter set list according to the LIC index;

determining parameters for applying the LIC based on the selected parameter set; and

performing the LIC on the current block based on the parameters for applying the LIC to generate compensated samples of the current block according to the reference block in the reference picture.

2 . The method of claim 1 , wherein the parameter set list has a predefined constant size.

3 . The method of claim 2 , further comprising:

decoding a syntax element of at least one of a sequence parameter set (SPS) level, a picture parameter set (PPS) level, a slice header level, and a picture header level, the syntax element having a value indicative of the predefined constant size.

4 . The method of claim 1 , further comprising:

decoding a flag that indicates a use of the LIC index for indicating the selected parameter set, the flag is of at least one of a sequence parameter set (SPS) level, a picture parameter sets (PPS) level, a slice header level, a picture header level, and a block level.

5 . The method of claim 1 , wherein the parameter set list comprises at least a parameter set that has been used for applying the LIC on a spatial adjacent neighboring block of the current block.

6 . The method of claim 1 , wherein the parameter set list is a history based parameter set list, and the method comprises:

adding a first parameter set into the history based parameter set list when the first parameter set is used for performing the LIC on a first block.

7 . The method of claim 6 , wherein the adding the first parameter set into the history based parameter set list further comprises:

adding the first parameter set into the history based parameter set list when a redundancy check confirms no identical parameter set to the first parameter set existing in the history based parameter set list.

8 . The method of claim 7 , further comprising:

determining that an identical parameter set to the first parameter set exists in the history based parameter set list; and

adjusting an order of the identical parameter set in the history based parameter set list.

9 . The method of claim 6 , wherein the history based parameter set list is configured to be first-in-first-out (FIFO).

10 . The method of claim 1 , further comprising:

obtaining a temporal parameter set that is used for performing the LIC on a collocated block in a collocated picture for the current block; and

performing the LIC on the current block based on the temporal parameter set to generate compensated samples of the current block according to the reference block in the reference picture.

11 . The method of claim 10 , further comprising:

decoding a flag indicative of using the temporal parameter set; and

performing the LIC on the current block based on the temporal parameter set when the flag indicates the temporal parameter set is used.

12 . The method of claim 10 , further comprising:

decoding a flag indicative of using an LIC merge list;

forming the LIC merge list that includes the parameter set list and the temporal parameter set; and

determining the selected parameter set from the LIC merge list based on the LIC index.

13 . The method of claim 1 , wherein the constructing the parameter set list further comprises:

scanning the spatial non adjacent blocks relative to the current block according to a predefined scanning order; and

adding available parameter sets of the spatial non adjacent blocks to the parameter set list until the parameter set list reaches a predefined list size.

14 . The method of claim 13 , wherein the parameter set list has no redundant parameter set.

15 . The method of claim 1 ,

wherein the flag is indicative of using the parameter set information from the spatial non adjacent blocks.

16 . The method of claim 1 , wherein the parameter set list comprises a first parameter set that is derived by minimizing a mean square error between a template of the current block and a reference template of the reference block.

17 . The method of claim 1 , further comprising:

decoding the LIC index without receiving a flag indicative of applying the LIC on the current block;

determining to disable the LIC when the LIC index is zero; and

applying the LIC on the current block when the LIC index is greater than zero.

18 . A method of video encoding, comprising:

determining to apply a local illumination compensation (LIC) on a current block in a current picture according to a reference block in a reference picture;

constructing a parameter set list for the LIC, the parameter set list including a plurality of parameter sets for the LIC, the constructing including scanning spatial non adjacent blocks relative to the current block to construct the parameter set list, the plurality of parameter sets for the LIC including a parameter set used to perform the LIC on one of the spatial non adjacent blocks;

selecting a parameter set from the parameter set list for the LIC, the LIC being applied on the current block based on the selected parameter set; and

encoding an LIC index and a flag into coded information of the current block in a bitstream, the LIC index being indicative of the selected parameter set from the parameter set list, the flag indicating that parameter set information from the spatial non adjacent blocks is used.

19 . A non-transitory computer-readable storage medium storing instructions which when executed by a processor cause the processor to perform an encoding method comprising:

determining to apply a local illumination compensation (LIC) on a current block in a current picture according to a reference block in a reference picture;

constructing a parameter set list for the LIC, the parameter set list including a plurality of parameter sets for the LIC, the constructing including scanning spatial non adjacent blocks relative to the current block to construct the parameter set list, the plurality of parameter sets for the LIC including a parameter set used to perform the LIC on one of the spatial non adjacent blocks;

selecting a parameter set from the parameter set list for the LIC, the LIC being applied on the current block based on the selected parameter set;

encoding an LIC index and a flag into coded information of the current block in a bitstream, the LIC index being indicative of the selected parameter set from the parameter set list, the flag indicating that parameter set information from the spatial non adjacent blocks is used; and

transmitting the bitstream.

20 . The method of claim 1 , wherein

the method further includes decoding parameter residual information from the coded video bitstream; and

the determining the parameters includes determining the parameters based on the selected parameter set and the parameter residual information, the parameter residual information indicating differences between the parameters and the selected parameter set.

Assignments (1)

Continuity (2)

References Cited (20)