Patent ID: 11924414
Assignee: GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A method of encoding an image, comprising:
determining an intra prediction mode of a current block, wherein the intra prediction mode of the current block is determined for each of a luma block and a chroma block respectively, an MPM (Most Probable Mode) index is derived based on the intra prediction mode of the luma block and an MPM list, and the MPM list includes an intra prediction mode of a neighboring block (ModeA), ModeA+n, and ModeA−n;
performing intra prediction on the current block based on the intra prediction mode; and
encoding the MPM index into a bitstream,
wherein performing the intra prediction comprises:
specifying a luma region for inter-components reference of the chroma block;
performing down-sampling for the luma region;
deriving a parameter for the inter-components reference of the chroma block; and
predicting the chroma block based on the down-sampled luma region and the parameter;
wherein the luma region comprises a luma block and a neighboring region adjacent to the luma block, and performing down-sampling for the luma region comprises:
performing down-sampling for the neighboring region adjacent to the luma block based on:

pLeftDsY[y]=(pY[−2][2×y−1]+pY[−3][2×y]+4×pY[−2][2×y]+pY[−1][2×y]+pY[−2][2×y+1]+4)>>3.