Intra-frame decoding method and apparatus for signal component sampling point of image block

An intra-frame decoding method for a signal component sampling point of an image block, the method comprising:

• obtaining prediction mode information about a current block from a video code stream;
• determining a prediction mode for the current block according to the prediction mode information about the current block, wherein the prediction mode for the current block is used to predict a first signal component and a second signal component of the current block;
• obtaining a prediction value of a first signal component sampling point of the current block according to the prediction mode for the current block;
• and
• obtaining a reconstruction value of the first signal component sampling point of the current block according to the prediction value of the first signal component sampling point of the current block.

An intra-frame decoding apparatus for a signal component sampling point of an image block, the apparatus comprising:

• a first obtaining unit, configured to obtain prediction mode information about a first signal component of a current block from a video code stream;
• a first determining unit, configured to determine a prediction mode for the first signal component of the current block according to the prediction mode information about the first signal component of the current block, wherein the prediction mode for the first signal component of the current block is one of a DM mode and an LM mode;
• a first predicting unit, configured to obtain a prediction value of a first signal component sampling point of the current block according to the prediction mode for the first signal component of the current block;
• and
• a first computing unit, configured to obtain a reconstruction value of the first signal component sampling point of the current block according to the prediction value of the first signal component sampling point of the current block.