US 11,956,439 B2
Signaling of chroma residual scaling
Zhipin Deng, Beijing (CN); Li Zhang, San Diego, CA (US); Hongbin Liu, Beijing (CN); Kai Zhang, San Diego, CA (US); and Jizheng Xu, San Diego, CA (US)
Assigned to BEIJING BYTEDANCE NETWORK TECHNOLOGY CO., LTD., Beijing (CN); and BYTEDANCE INC., Los Angeles, CA (US)
Filed by Beijing Bytedance Network Technology Co., Ltd., Beijing (CN); and Bytedance Inc., Los Angeles, CA (US)
Filed on Oct. 31, 2022, as Appl. No. 17/977,471.
Application 17/977,471 is a continuation of application No. 17/567,717, filed on Jan. 3, 2022, granted, now 11,533,487.
Application 17/567,717 is a continuation of application No. PCT/CN2020/100573, filed on Jul. 7, 2020.
Claims priority of application No. PCT/CN2019/094964 (WO), filed on Jul. 7, 2019.
Prior Publication US 2023/0096945 A1, Mar. 30, 2023
Int. Cl. H04N 19/132 (2014.01); H04N 19/105 (2014.01); H04N 19/176 (2014.01); H04N 19/186 (2014.01); H04N 19/30 (2014.01); H04N 19/70 (2014.01)
CPC H04N 19/132 (2014.11) [H04N 19/105 (2014.11); H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/30 (2014.11); H04N 19/70 (2014.11)] 18 Claims
OG exemplary drawing
 
1. A method of processing video data, comprising:
determining, during a conversion between a current chroma video block of a video and a bitstream of the video, that a scaling process is applied on chroma residual samples of the current chroma video block; and
performing the conversion based on the determining,
wherein in the scaling process, the chroma residual samples are scaled based on at least one scaling factor before being used to reconstruct the current chroma video block; and
wherein one or more chroma video blocks within a video region comprising the current chroma video block share the same at least one scaling factor in the scaling process;
wherein the at least one scaling factor is derived by following:
checking an availability of each of one or more neighboring luma blocks of a video unit of the video which determined based on a luma sample corresponding to a top-left sample of the current chroma video block;
determining, based on the availability of the each of the one or more neighboring luma blocks, whether to retrieve neighboring luma samples of the video unit, wherein the neighboring luma samples located in predefined positions neighboring to the video unit; and
deriving the at least one scaling factor based on an averaged luma variable computed using the neighboring luma samples by an average operation in case that at least one of the one or more neighboring luma blocks is available, and
wherein in response to the one or more neighboring luma blocks being determined to be unavailable, the at least one scaling factor is derived by setting the averaged luma variable equal to a default value, and
wherein the default value equals to 1<<(bitDepth−1), where bitDepth is a bit depth of the video.