US 11,863,748 B2
Encoder, a decoder and corresponding methods of chroma qantization control
Sergey Yurievich Ikonin, Moscow (RU); Roman Igorevich Chernyak, Moscow (RU); Timofey Mikhailovich Solovyev, Moscow (RU); Alexander Alexandrovich Karabutov, Moscow (RU); and Elena Alexandrovna Alshina, Munich (DE)
Assigned to HUAWEI TECHNOLOGIES CO., LTD., Shenzhen (CN)
Filed by HUAWEI TECHNOLOGIES CO., LTD., Guangdong (CN)
Filed on Dec. 9, 2021, as Appl. No. 17/547,169.
Application 17/547,169 is a continuation of application No. PCT/RU2020/050131, filed on Jun. 22, 2020.
Claims priority of application No. PCT/RU2019/000445 (WO), filed on Jun. 21, 2019.
Prior Publication US 2022/0103822 A1, Mar. 31, 2022
Int. Cl. H04N 19/124 (2014.01); H04N 19/186 (2014.01); H04N 19/196 (2014.01)
CPC H04N 19/124 (2014.11) [H04N 19/186 (2014.11); H04N 19/196 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method of obtaining quantization parameters (QPs) for chrominance components based on QPs for luminance components, wherein the method is performed by a decoder or encoder, comprising:
obtaining a luminance QP for a luma component of a coding unit;
obtaining a QP index (QPi) based at least in a part on the luminance QP;
obtaining a chrominance QP (QPc) for a chroma component of the coding unit based on the QP index using a preset lookup table, wherein the maximum difference between the QP index and the QPc is equal to 3.