US 12,284,370 B2
Image decoding method for chroma quantization parameter data and apparatus therefor
Seethal Paluri, Seoul (KR); Seunghwan Kim, Seoul (KR); and Jie Zhao, Seoul (KR)
Assigned to LG Electronics Inc., Seoul (KR)
Filed by LG Electronics Inc., Seoul (KR)
Filed on May 13, 2024, as Appl. No. 18/662,228.
Application 18/662,228 is a continuation of application No. 17/623,386, granted, now 12,015,792, previously published as PCT/KR2020/008131, filed on Jun. 24, 2020.
Claims priority of provisional application 62/867,875, filed on Jun. 28, 2019.
Prior Publication US 2024/0305795 A1, Sep. 12, 2024
Int. Cl. H04N 19/124 (2014.01); H04N 19/107 (2014.01); H04N 19/12 (2014.01); H04N 19/132 (2014.01); H04N 19/159 (2014.01); H04N 19/172 (2014.01); H04N 19/18 (2014.01); H04N 19/186 (2014.01); H04N 19/61 (2014.01); H04N 19/70 (2014.01)
CPC H04N 19/186 (2014.11) [H04N 19/107 (2014.11); H04N 19/12 (2014.11); H04N 19/124 (2014.11); H04N 19/132 (2014.11); H04N 19/159 (2014.11); H04N 19/172 (2014.11); H04N 19/18 (2014.11); H04N 19/61 (2014.11); H04N 19/70 (2014.11)] 3 Claims
OG exemplary drawing
 
1. A decoding apparatus for image decoding, the decoding apparatus comprising:
a memory; and
at least one processor connected to the memory, the at least one processor configured to:
obtain image information including prediction information, residual information for chroma components, and a flag representing whether one chroma quantization parameter table is applied or not;
obtain chroma quantization parameter data based on the flag;
derive at least one chroma quantization parameter table based on the chroma quantization parameter data;
derive at least one chroma quantization parameter for the chroma components based on the at least one chroma quantization parameter table;
derive prediction samples for the chroma components based on the prediction information;
derive transform coefficients for the chroma components based on the residual information;
derive residual samples for chroma components by dequantizing the transform coefficients based on the at least one chroma quantization parameter; and
generate a reconstructed picture based on the prediction samples and the residual samples,
wherein the flag equal to 0 represents that a first chroma quantization parameter table for a Cb component, a second chroma quantization parameter table for a Cr component, and a third chroma quantization parameter table for a joint CbCr component are signaled.