Patent ID: 11936875
Assignee: LG ELECTRONICS INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
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 residual information through a bitstream;
derive quantized transform coefficients based on the residual information;
derive transform coefficients based on a dequantization process for the quantized transform coefficients;
derive residual samples based on an inverse transform process for the transform coefficients;
generate reconstructed samples based on the residual samples, wherein the reconstructed samples include reconstructed luma samples and reconstructed chroma samples;
derive ALF filter coefficients for an adaptive loop filtering (ALF) process of the reconstructed chroma samples;
generate filtered reconstructed chroma samples based on the reconstructed chroma samples and the ALF filter coefficients;
derive cross-component filter coefficients for cross-component filtering; and
generate modified filtered reconstructed chroma samples based on the reconstructed luma samples, the filtered reconstructed chroma samples, and the cross-component filter coefficients,
wherein the image information includes header information and an adaptation parameter set (APS) including ALF data,
wherein the cross-component filter coefficients are derived based on the ALF data,
wherein the header information includes a first flag related to whether a cross-component adaptive loop filter (CCALF) is enabled for a Cb color component of the filtered reconstructed chroma samples,
wherein based on the determination that a value of the first flag is 1, the header information includes information related to an identifier of the APS for deriving the cross-component filter coefficients for the Cb color component,
wherein the ALF data included in the APS for deriving the cross-component filter coefficients for the Cb color component include a Cb filter signal flag related to whether the cross-component filters for the Cb color component are signaled,
wherein based on the Cb filter signal flag, the ALF data included in the APS for deriving the cross-component filter coefficients for the Cb color component include information related to the number of cross-component filters for the Cb color component,
wherein based on the information related to the number of cross-component filters for the Cb color component, the ALF data included in the APS for deriving the cross-component filter coefficients for the Cb color component include information on absolute values of the cross-component filter coefficients for the Cb color component and information on signs of the cross-component filter coefficients for the Cb color component, and
wherein the cross-component filter coefficients for the Cb color component are derived based on the information on the absolute values of the cross-component filter coefficients for the Cb color component and the information on the signs of the cross-component filter coefficients for the Cb color component.