Chroma intra prediction method and device

A chroma intra prediction method, applied to an encoder, the method comprising:

• determining that a prediction mode corresponding to a current chroma block is a direct mode (DM);
• before determining a set of chroma prediction modes based on at least one modified candidate mode, acquiring a linear mode corresponding to the current chroma block from bitstream data;
• determining an intra prediction mode of the current chroma block from a set of chroma prediction modes, wherein the set of chroma prediction modes comprises at least one of the DM or the linear mode;
• and
• determining a reconstructed value of the current chroma block according to the intra prediction mode.

A chroma intra prediction device, applied to a decoder, the device comprising:

• a processor, a memory storing instructions executable by the processor, a communication interface, and a bus for connecting the processor, the memory and the communication interface, wherein the processor is configured to execute the instructions to perform operations of:
• parsing bitstream data corresponding to a current chroma block, and determining that a prediction mode corresponding to the current chroma block is a direct mode (DM);
• before determining a set of chroma prediction modes based on at least one modified candidate mode, acquiring a linear mode corresponding to the current chroma block from the bitstream data;
• determining an intra prediction mode of the current chroma block from a set of chroma prediction modes, wherein the set of chroma prediction modes comprises at least one of the DM or the linear mode;
• and
• determining a reconstructed value of the current chroma block according to the intra prediction mode.

A chroma intra prediction device, applied to an encoder, the device comprising:

• a processor, a memory storing instructions executable by the processor, a communication interface, and a bus for connecting the processor, the memory and the communication interface, wherein the processor is configured to execute the instructions to perform operations of:
• determining that a prediction mode corresponding to a current chroma block is a direct mode (DM);
• before determining a set of chroma prediction modes based on at least one modified candidate mode, acquiring a linear mode corresponding to the current chroma block from bitstream data;
• determining an intra prediction mode of the current chroma block from a set of chroma prediction modes, wherein the set of chroma prediction modes comprises at least one of the DM or the linear mode;
• and
• determining a reconstructed value of the current chroma block according to the intra prediction mode.