IMAGE ENCODING METHOD BASED ON INSEPARABLE SECONDARY TRANSFORMATION AND DEVICE FOR IT Russian patent published in 2022 - IPC H04N19/40 H04N19/176 H04N19/186 H04N19/119 H04N19/70 H04N19/167 

FIELD: images encoding and decoding.

SUBSTANCE: invention relates to means for encoding and decoding images. Next, prediction mode information and residual information from the bitstream are obtained. Prediction samples are obtained for the target block based on the prediction mode information. The target block transform coefficients are obtained based on the residual information. Residual samples of the target block are obtained based on the inverse transform for the transform coefficients of the target block. A reconstructed frame is generated based on prediction samples and residual samples. Obtaining the transform coefficients of the target block comprises obtaining a non-separable transform index for the target block, wherein the inverse transform is performed based on the non-separable transform index. When the value of the non-separable transform index is not 0, the inverse transform for the coefficients included in the upper left target area of ​​the target block is performed based on the transform matrix associated with the non-separable transform index.

EFFECT: improving encoding efficiency.

16 cl, 18 dwg, 5 tbl