Patent ID: 11889082
Assignee: LG ELECTRONICS INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. An image decoding method performed by a decoding apparatus, the method comprising:
obtaining image information including prediction mode information, residual information and luma mapping with chroma scaling (LMCS) related information from a bitstream;
deriving an inter prediction mode for a current block in a current picture based on the prediction mode information;
generating predicted luma samples based on the inter prediction mode;
generating residual luma sample based on the residual information;
generating mapped predicted luma samples based on a mapping process for luma samples; and
generating reconstructed luma samples based on the mapped predicted luma samples and the residual luma samples,
wherein the image information includes LMCS adaptation parameter sets (APSs),
wherein an LMCS APS includes an LMCS data field,
wherein the LMCS data field includes the LMCS related information,
wherein LMCS codewords used in the mapping process and an inverse mapping process are derived based on the LMCS data field,
wherein the mapped predicted luma samples are generated based on the LMCS codewords,
wherein a maximum number of the LMCS APSs is a specific value, and
wherein the specific value is 4.