AN APPARATUS, A METHOD AND A COMPUTER PROGRAM FOR VIDEO CODING AND DECODING

原文（中国語）

A method comprising receiving an image block unit of a frame, the image block unit being predicted using a cross-component prediction mode and comprising samples in color channels comprising at least one chrominance channel and one luminance channel (); determining intra prediction direction based on the samples of said luminance channels of the image block unit, samples in a neighborhood of the luminance channel of the block unit and/or samples in the neighborhood of the block unit (); selecting a low-frequency nonseparable transform index for low-frequency non-separable transform using the determined intra prediction direction (); and performing the low-frequency non-separable transform using the selected low-frequency non-separable transform index ().