Method and apparatus for intra-prediction coding of video data

A method for encoding video data, the method comprising:

• determining a luma intra prediction type and a luma intra prediction mode of a current coding block, the luma intra prediction type comprising matrix-based intra prediction (MIP) and regular intra prediction;
• encoding, into a bitstream, information on the luma intra prediction type and the luma prediction mode of the current coding block;
• determining a chroma prediction type and a chroma intra prediction mode of a current coding block;
• encoding, into a bitstream, information on the chroma prediction mode of the current coding block, based on the luma intra prediction type and the luma intra prediction mode of the current coding block;
• and
• generating chroma prediction samples of the current coding block based on the chroma intra prediction mode of the current coding block,
• wherein, when the luma intra prediction type of the current coding block is the matrix-based intra prediction:
• if a sampling format of the video data is 4:4:4, the information on the chroma prediction mode indicating a direct mode (DM) means that the chroma intra prediction type of the current coding block is the matrix-based intra prediction and the chroma intra prediction mode of the current coding block is the same as a matrix-based intra prediction mode determined as the luma intra prediction mode of the current coding block;
• and
• if a sampling format of the video data is not 4:4:4, the information on the chroma prediction mode indicating the direct mode means that the chroma intra prediction type of the current coding block is the regular intra prediction and the chroma intra prediction mode of the current coding block is a PLANAR mode.

A method for providing a video decoding device with video data, the method comprising:

• encoding the video data into a bitstream;
• and
• transmitting the bitstream to the video decoding device,
• wherein the encoding of the video data includes:
• determining a luma intra prediction type and a luma intra prediction mode of a current coding block, the luma intra prediction type comprising matrix-based intra prediction (MIP) and regular intra prediction;
• encoding, into a bitstream, information on the luma intra prediction type and the luma prediction mode of the current coding block;
• determining a chroma prediction type and a chroma intra prediction mode of a current coding block;
• encoding, into a bitstream, information on the chroma prediction mode of the current coding block, based on the luma intra prediction type and the luma intra prediction mode of the current coding block;
• and
• generating chroma prediction samples of the current coding block based on the chroma intra prediction mode of the current coding block,
• wherein, when the luma intra prediction type of the current coding block is the matrix-based intra prediction:
• if a sampling format of the video data is 4:4:4, the information on the chroma prediction mode indicating a direct mode (DM) means that the chroma intra prediction type of the current coding block is the matrix-based intra prediction and the chroma intra prediction mode of the current coding block is the same as a matrix-based intra prediction mode determined as the luma intra prediction mode of the current coding block;
• and
• if a sampling format of the video data is not 4:4:4, the information on the chroma prediction mode indicating the direct mode means that the chroma intra prediction type of the current coding block is the regular intra prediction and the chroma intra prediction mode of the current coding block is a PLANAR mode.