US 12,069,311 B2
Methods and apparatus of video coding in 4:4:4 chroma format
Xiaoyu Xiu, Beijing (CN); Yi-Wen Chen, Beijing (CN); Tsung-Chuan Ma, Beijing (CN); Hong-Jheng Jhu, Beijing (CN); Xianglin Wang, Beijing (CN); and Bing Yu, Beijing (CN)
Assigned to BEIJING DAJIA INTERNET INFORMATION TECHNOLOGY CO., LTD., Beijing (CN)
Filed by BEIJING DAJIA INTERNET INFORMATION TECHNOLOGY CO., LTD., Beijing (CN)
Filed on Apr. 8, 2022, as Appl. No. 17/716,971.
Application 17/716,971 is a continuation of application No. PCT/US2020/055264, filed on Oct. 12, 2020.
Claims priority of provisional application 62/923,390, filed on Oct. 18, 2019.
Claims priority of provisional application 62/914,282, filed on Oct. 11, 2019.
Prior Publication US 2022/0303580 A1, Sep. 22, 2022
Int. Cl. H04N 19/70 (2014.01); H04N 19/12 (2014.01); H04N 19/132 (2014.01); H04N 19/136 (2014.01); H04N 19/174 (2014.01); H04N 19/186 (2014.01); H04N 19/30 (2014.01); H04N 19/60 (2014.01)
CPC H04N 19/70 (2014.11) [H04N 19/12 (2014.11); H04N 19/132 (2014.11); H04N 19/136 (2014.11); H04N 19/174 (2014.11); H04N 19/186 (2014.11); H04N 19/30 (2014.11); H04N 19/60 (2014.11)] 18 Claims
OG exemplary drawing
 
1. A method of video decoding, comprising:
obtaining, from a bitstream, a first syntax element in one slice header associated with a slice, wherein the first syntax element indicates whether luma mapping with chroma scaling (LMCS) is applied to coding units in the slice;
obtaining, from the bitstream, a second syntax element for one coding unit in the slice, wherein the second syntax element indicates whether the coding unit has been coded using adaptive color-space transform (ACT);
in accordance with a determination that the second syntax element has a non-zero value, applying inverse ACT to convert luma and chroma residuals of the coding unit from one transformed color space to an original color space of video data; and
after applying the inverse ACT to convert luma and chroma residuals of the coding unit, in accordance with a determination that the first syntax element has a non-zero value, deriving intermediate luma samples based on the luma residuals of the coding unit in the original color space, performing inverse luma mapping using the intermediate luma samples and performing inverse scaling using the chroma residuals of the coding unit in the original color space.