US-20260129238-A1 - METHOD, APPARATUS, AND MEDIUM FOR VIDEO PROCESSING

Abstract

Embodiments of the disclosure provide a solution for video processing. A method for video processing is proposed. The method includes: deriving, for a conversion between a video unit of a video and a bitstream of the video, a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample out of a neighbouring row, or a reconstructed sample out of a column adjacent to a current block, in response to the video unit being coded with a first target coding mode; and performing the conversion based on the LIC parameter.

Inventors

• Yang Wang
• Kai Zhang
• Yuwen He
• Hongbin Liu
• Li Zhang

Assignees

• Douyin Vision Co., Ltd.

Dates

Publication Date

20260507

Application Date

20251229

Priority Date

20230627

Claims (20)

1. 1 . A method for video processing, comprising: deriving, for a conversion between a video unit of a video and a bitstream of the video, a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to the video unit being coded with a first target coding mode; and performing the conversion based on the LIC parameter.
2. 2 . The method of claim 1 , wherein at least one of: a reconstructed sample of the neighbouring row or a reconstructed sample of a column adjacent to the current block is excluded to derive the LIC parameter.
3. 3 . The method of claim 1 , wherein a template comprises one or more neighbouring reconstructed samples, wherein W T represents a width of the template and H T represents a height of the template.
4. 4 . The method of claim 3 , wherein a sample of an above template is used to derive the LIC parameters, and/or wherein a sample of a left template is used to derive the LIC parameters, and/or wherein a sample of a left-bottom template is used to derive the LIC parameters, and/or wherein a sample of a right-above template is used to derive the LIC parameters, and/or wherein a sample of a left-above template is used to derive the LIC parameters, and/or wherein a plurality of the following templates: above template, left template, right-above template, left-bottom template, and left-above template are combined into one template that is used to derive the LIC parameter, and/or wherein a L-shape template is used to derive the LIC parameter, and/or wherein a non-adjacent template is used to derive the LIC parameter, and/or wherein at least one of: W T or H T equals to 1, and/or wherein the template comprises a plurality of rows and/or a plurality of columns, and/or wherein samples of the template are in the same coding tree unit (CTU), the same CTU row, the same CTU tile, or the same CTU slice of the video unit.
5. 5 . The method of claim 3 , wherein the template comprises at least one of: a neighbouring reconstructed sample of a row except for a nearest row, or a neighbouring reconstructed sample of a column except for a nearest column, wherein line X represents at least one of: the row, or the column.
6. 6 . The method of claim 5 , wherein X is an integer larger than 0, and/or wherein a left-above sample of the line X is used, and/or wherein samples of a plurality of rows or columns are used, and/or wherein at least one of: the row or the column is in the same CTU, the same CTU row, the same CTU tile, or the same CTU slice of the video unit.
7. 7 . The method of claim 1 , wherein if above samples are not available, a left sample is used to derive the LIC parameter.
8. 8 . The method of claim 1 , wherein if left samples are not available, an above sample is used to derive the LIC parameter.
9. 9 . The method of claim 1 , wherein a determination of a template is signalled, wherein the template is used to derive the LIC parameter.
10. 10 . The method of claim 9 , wherein one or more syntax elements are used to indicate which template is used to derive the LIC parameter, and/or wherein reordering is used in the determination of the template.
11. 11 . The method of claim 10 , wherein an index of the template is signalled, and/or wherein the one or more syntax elements are signalled if a condition is satisfied, and/or wherein if a set of templates are at least one of: predefined, signalled, or derived, and the reordering is performed for the set of templates, an indication of first M templates after reordering is signalled, wherein M is an integer number, and/or wherein at least one of: template matching cost, or bilateral matching cost is used in the reordering.
12. 12 . The method of claim 11 , wherein the index of the template comprises an index of a line number, and/or wherein the index of the template comprises a predefined template, and/or wherein the condition comprises at least one of: whether LIC is allowed to be used, whether LIC is used, or whether one or more template samples are available, and/or wherein different LIC parameters are derived using different templates, and wherein a prediction of a current template is refined using the LIC parameter and used to calculate template matching (TM) cost.
13. 13 . The method of claim 1 , wherein a determination of a template is derived, wherein the template is used to derive the LIC parameter.
14. 14 . The method of claim 13 , wherein at least one of: TM cost, or bilateral matching (BM) cost is used to determine the template, and/or wherein a reordering approach is used, and a best template is determined as a template with best cost.
15. 15 . The method of claim 1 , wherein the first target coding mode is applied to advanced motion vector prediction (AMVP) mode, and/or wherein the first target coding mode is applied to merge mode.
16. 16 . The method of claim 15 , wherein the AMVP mode comprises at least one of: regular AMVP mode, affine AMVP mode, TM AMVP mode, or intra block copy (IBC) AMVP mode, and/or wherein the first target coding mode is not used for TM AMVP mode, and/or wherein the first target coding mode is used for TM AMVP mode but the first target coding mode is not used to construct a TM based AMVP candidate list, and/or wherein the merge mode comprises at least one of: regular merge mode, sub-block-based merge mode, TM merge mode, affine merge mode, merge mode with motion vector differences (MMVD), or IBC merge mode, and/or wherein at least one of: a template, or an indication of the template is inherited for the merge mode, wherein at least one of: the template, or the indication of the template is used to derive the LIC parameter, and/or wherein at least one of: a template, or an indication of the template is signalled for the merge mode, and/or wherein at least one of: a template, or an indication of the template is derived for the merge mode, and/or wherein the first target coding mode is applied to an adaptive reordering of merge candidates (ARMC) process, and/or wherein the first target coding mode is not applied to an ARMC process.
17. 17 . The method of claim 1 , wherein the conversion includes encoding the video unit into the bitstream, or wherein the conversion includes decoding the video unit from the bitstream.
18. 18 . An apparatus for video processing comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to perform acts comprising: deriving, for a conversion between a video unit of a video and a bitstream of the video, a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to the video unit being coded with a first target coding mode; and performing the conversion based on the LIC parameter.
19. 19 . A non-transitory computer-readable storage medium storing instructions that cause a processor to perform acts comprising: deriving, for a conversion between a video unit of a video and a bitstream of the video, a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to the video unit being coded with a first target coding mode; and performing the conversion based on the LIC parameter.
20. 20 . A non-transitory computer-readable recording medium storing a bitstream of a video which is generated by a method performed by an apparatus for video processing, wherein the method comprises: deriving a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to a video unit of the video being coded with a first target coding mode; and generating the bitstream based on the LIC parameter.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of International Application No. PCT/CN2024/101758, filed on Jun. 26, 2024, which claims the benefit of International Application No. PCT/CN2023/102887, filed on Jun. 27, 2023. The entire contents of these applications are hereby incorporated by reference in their entireties. FIELDS Embodiments of the present disclosure relates generally to video processing techniques, and more particularly, to local illumination compensation with multiple templates. BACKGROUND In nowadays, digital video capabilities are being applied in various aspects of peoples' lives. Multiple types of video compression technologies, such as MPEG-2, MPEG-4, ITU-TH.263, ITU-TH.264/MPEG-4 Part 10 Advanced Video Coding (AVC), ITU-TH.265 high efficiency video coding (HEVC) standard, versatile video coding (VVC) standard, have been proposed for video encoding/decoding. However, the coding performance of video coding techniques is generally expected to be further improved. SUMMARY Embodiments of the present disclosure provide a solution for video processing. In a first aspect, a method for video processing is proposed. The method comprises: deriving, for a conversion between a video unit of a video and a bitstream of the video, a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to the video unit being coded with a first target coding mode; and performing the conversion based on the LIC parameter. Compared with the conventional solution, the method in accordance with the first aspect of the present disclosure can improve the coding performance of LIC by increasing the diversity of derived parameters. In a second aspect, another method for video processing is proposed. The method comprises: applying, for a conversion between a video unit of a video and a bitstream of the video, a plurality of local illumination compensation (LIC) models to the video unit, in response to the video unit being coded with a second target coding mode; and performing the conversion based on the plurality of LIC models. Compared with the conventional solution, the method in accordance with the second aspect of the present disclosure can improve the coding performance of LIC by applying a plurality of LIC models. In a third aspect, an apparatus for video processing is proposed. The apparatus comprises a processor and a non-transitory memory with instructions thereon. The instructions upon execution by the processor, cause the processor to perform a method in accordance with the first, or second aspect of the present disclosure. In a fourth aspect, a non-transitory computer-readable storage medium is proposed. The non-transitory computer-readable storage medium stores instructions that cause a processor to perform a method in accordance with the first, or second aspect of the present disclosure. In a fifth aspect, another non-transitory computer-readable recording medium is proposed. The non-transitory computer-readable recording medium stores a bitstream of a video which is generated by a method performed by an apparatus for video processing. The method comprises: deriving a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to a video unit of the video being coded with a first target coding mode; and generating the bitstream based on the LIC parameter. In a sixth aspect, another non-transitory computer-readable recording medium is proposed. The non-transitory computer-readable recording medium stores a bitstream of a video which is generated by a method performed by an apparatus for video processing. The method comprises: applying a plurality of local illumination compensation (LIC) models to a video unit of the video, in response to the video unit of the video being coded with a second target coding mode; and generating the bitstream based on the plurality of LIC models. In a seventh aspect, a method for storing a bitstream of a video is proposed. The method comprises: deriving a local illumination compensation (LIC) parameter using at least one of: a reconstructed sample of a neighbouring row, or a reconstructed sample of a column adjacent to a current block, in response to a video unit of the video being coded with a first target coding mode; generating the bitstream based on the LIC parameter; and storing the bitstream in a non-transitory computer-readable recording medium. In an eighth aspect, a method for storing a bitstream of a video is proposed. The method comprises: applying a plurality of local illumination compensation (LIC) models to a video unit of the video, in response to the video unit of the video being coded with a second target coding mode; generating the bitstream based on the plurality