IMAGE ENCODING METHOD BASED ON INSEPARABLE SECONDARY TRANSFORMATION AND DEVICE FOR IT Russian patent published in 2023 - IPC H04N19/40 H04N19/176 H04N19/186 H04N19/119 H04N19/70 H04N19/167 

FIELD: image encoding and decoding.

SUBSTANCE: residual information for the target block is obtained from the bitstream. The target block transform ratio are obtained based on the residual information. The transform ratio are scanned from the (R+1)th to the Nth among the transform ratio of the target block. An inseparable transform index for the target block is obtained based on a scan of the (R+1)th to Nth transform ratio. The residual discrete samples of the target block are obtained based on the inverse transform for the transform ratio of the target block, the inverse transform being based on the inseparable transform index. A reconstructed frame is formed on the basis of residual discrete samples. Apply deblocking filtering to the reconstructed frame. As a non-separable transform index value, 0 is obtained when a non-zero transform ratio is included in the (R+1)th to Nth transform ratio.

EFFECT: increased efficiency of image encoding.

13 cl, 18 dwg, 5 tbl