Method and apparatus for intra prediction in video coding

An encoding method, comprising:

• determining a list of most probable modes (MPMs) for a current block of a video, wherein when a condition is satisfied, the list of MPMs includes:
• a direct current (DC) mode, an intra prediction mode corresponding to a value of 50, an intra prediction corresponding to a value of 18, an intra prediction mode corresponding to a value of 46, and an intra prediction mode corresponding to a value of 54;
• determining an intra prediction mode for the current block based on samples of neighboring blocks of the current block;
• obtaining a prediction block for the current block based on the intra prediction mode for the current block;
• obtaining a residual block for the current block based on the current block and the prediction block for the current block;
• encoding the residual block for the current block into a video bitstream;
• encoding an MPM flag into the video bitstream, wherein the MPM flag indicates whether the intra prediction mode for the current block is in the list of MPMs;
• and
• when the intra prediction mode for the current block is in the list of MPMs, encoding an MPM index into the video bitstream to indicate the intra prediction mode for the current block.

A non-transitory computer-readable storage medium storing an encoded video bitstream that, when decoded by a coding device, is used by the coding device to generate a video, the encoded video bitstream comprising:

• data for obtaining a residual block for a current block and a plurality of syntax elements comprising a most probable mode (MPM) flag indicating whether an intra prediction mode for the current block is in a list of MPMs, wherein when a condition is satisfied, the list of MPMs includes:
• a direct current (DC) mode, an intra prediction mode corresponding to a value of 50, an intra prediction corresponding to a value of 18, an intra prediction mode corresponding to a value of 46, and an intra prediction mode corresponding to a value of 54;
• wherein:
• the plurality of syntax elements further comprise an MPM index indicating the intra prediction mode for the current block when the intra prediction mode for the current block is in the list of MPMs;
• the intra prediction mode for the current block is for obtaining a prediction block for the current block;
• and
• the residual block for the current block and the prediction block for the current block are for reconstructing the current block.