Video encoding, decoding method and decoder

A method for encoding a video, applied to an encoder and comprising:

• determining a first-type intra prediction mode parameter;
• determining first prediction values of a current block according to the first-type intra prediction mode parameter, and calculating residuals between original values of the current block and the first prediction values;
• determining a first transform parameter of the current block based on the first prediction values of the current block or the first-type intra prediction mode parameter of the current block;
• determining, based on the first transform parameter, a second transform parameter for transforming the current block;
• and
• transforming, based on the second transform parameter, the residuals to obtain transform coefficients of the current block.

A decoder, comprising:

• a memory configured to store a computer program executable on a processor;
• and
• the processor configured to execute the computer program to implement operations of:
• decoding a bitstream to determine a first-type intra prediction mode parameter of a current block;
• determining first prediction values of the current block according to the first-type intra prediction mode parameter;
• determining a first transform parameter of the current block based on the first prediction values of the current block or the first-type intra prediction mode parameter of the current block;
• determining, based on the first transform parameter, a second transform parameter for transforming the current block;
• transforming, based on the second transform parameter, transform coefficients of the current block to determine residuals of the current block;
• and
• determining reconstructed values of the current block based on the residuals and the first prediction values.