Video Coding Using Intra Sub-Partition Coding Mode

An apparatus of video encoding, comprising:

• one or more processors;
• a non-transitory computer-readable memory storing instructions executable by the one or more processors,
• wherein the one or more processors are configured to:
• perform an intra prediction for a plurality of sub-partitions of a coding block in a Intra Sub-Partition (ISP) mode in response to determining that the plurality of sub-partitions meet first conditions for the intra prediction,
• wherein performing the intra prediction for the plurality of sub-partitions of the coding block comprises:
• merging at least two sub-partitions of the plurality of sub-partitions into one prediction region for the intra prediction, and
• generating predicted samples for the one prediction region in the intra prediction based on a plurality of reference samples of the coding block adjacent to the one prediction region,
• wherein the first conditions comprise that the plurality of sub-partitions are a plurality of vertical sub-partitions and each of the sub-partitions has a width less than or equal to 2.

A computer readable storage medium storing a bitstream generated by the encoding method comprising:

• performing an intra prediction for a plurality of sub-partitions of a coding block in a Intra Sub-Partition (ISP) mode in response to determining that the plurality of sub-partitions meet first conditions for the intra prediction,
• wherein performing the intra prediction for the plurality of sub-partitions of the coding block comprises:
• merging at least two sub-partitions of the plurality of sub-partitions into one prediction region for the intra prediction, and
• generating predicted samples for the one prediction region in the intra prediction based on a plurality of reference samples of the coding block adjacent to the one prediction region,
• wherein the first conditions comprise that the plurality of sub-partitions are a plurality of vertical sub-partitions and each of the sub-partitions has a width less than or equal to 2.