METHOD AND DEVICE FOR INTRA-FRAME PREDICTION USING LINEAR MODEL Russian patent published in 2023 - IPC H04N19/186 H04N19/11 H04N19/136 

FIELD: image processing tools.

SUBSTANCE: set of downsampling filters is determined based on the chroma format information, wherein the chromaticity format information indicates the chroma format of the image to which the current block belongs. Downsamples are obtained from the reconstructed luminance samples in the luminance block of the current block and reference downsamples from the selected luminance reference samples of the luminance block using corresponding downsampling filters from the set of downsampling filters. One or more linear model coefficients are determined based on the reference downsamples and the chroma reference samples corresponding to the reference downsamples. Prediction samples of the chroma block corresponding to the luminance block are obtained based on the coefficients of the linear model and downsamples from the reconstructed luminance samples in the luminance block, wherein the selected reference luminance samples contain at least one of: adjacent luminance samples located above the luminance block and selected based on the L available chroma reference samples, or adjacent luminance samples remaining in the luminance block and selected based on the L available chroma reference samples.

EFFECT: improvement in intra-frame color prediction using intercomponent linear modelling.

25 cl, 10 tbl, 22 dwg