US 11,924,448 B2
Luma-mapping-based video or image coding
Jie Zhao, Seoul (KR); and Seunghwan Kim, Seoul (KR)
Assigned to LG ELECTRONICS, Seoul (KR)
Filed by LG Electronics Inc., Seoul (KR)
Filed on Nov. 30, 2022, as Appl. No. 18/072,390.
Application 18/072,390 is a continuation of application No. 17/556,095, filed on Dec. 20, 2021, granted, now 11,563,955.
Application 17/556,095 is a continuation of application No. PCT/KR2020/008047, filed on Jun. 22, 2020.
Claims priority of provisional application 62/864,481, filed on Jun. 20, 2019.
Prior Publication US 2023/0120963 A1, Apr. 20, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/186 (2014.01); H04N 19/132 (2014.01); H04N 19/136 (2014.01); H04N 19/176 (2014.01); H04N 19/44 (2014.01); H04N 19/117 (2014.01); H04N 19/70 (2014.01)
CPC H04N 19/186 (2014.11) [H04N 19/132 (2014.11); H04N 19/136 (2014.11); H04N 19/176 (2014.11); H04N 19/44 (2014.11); H04N 19/117 (2014.11); H04N 19/70 (2014.11)] 4 Claims
OG exemplary drawing
 
1. An image decoding method performed by a decoding apparatus, the method comprising:
obtaining image information including prediction mode information and luma mapping with chroma scaling (LMCS) related information from a bitstream;
deriving an inter prediction mode for a current block based on the prediction mode information;
deriving motion information for the current block based on the inter prediction mode;
generating prediction luma samples for the current block based on the motion information for the current block;
generating mapped prediction luma samples based on the prediction luma samples and the LMCS codewords;
generating reconstructed luma samples for the current block based on the mapped prediction luma samples;
generating modified reconstructed luma samples based on the reconstructed luma samples for the current block,
wherein the image information includes adaptation parameter sets (APSs),
wherein an APS includes type information indicating whether or not the APS is an LMCS APS,
wherein an APS of which the type information indicates that the APS is the LMCS APS includes an LMCS data field,
wherein the LMCS data field includes the LMCS related information,
wherein LMCS codewords for deriving the mapped prediction luma samples are derived based on the LMCS related information,
wherein a maximum number of LMCS APSs of the APSs is a specific value, and
wherein the specific value is four.