Patent ID: 11956462
Assignee: HFI INNOVATION INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 1:
2. A video processing method for sub-block motion compensation in a video coding system, comprising:
receiving input video data associated with a current block in a current picture;
partitioning the current block into multiple sub-blocks;
deriving sub-block Motion Vectors (MVs) associated with the sub-blocks in the current block according to a sub-block motion compensation coding tool;
constraining the sub-block MVs to form constrained sub-block MVs by restricting a difference between a primary MV and each sub-block MV of the sub-block MVs within one or more thresholds, the one or more thresholds corresponding to a restriction range around the primary MV, wherein said one or more thresholds are adaptively determined depending on a size, width, or height of the current block or a sub-block, an inter prediction direction of one of control point MVs of the current block, the current block, or a current sub-block, the control point MVs of the current block, or a combination thereof;
deriving a primary reference block, wherein a size or shape of the primary reference block is adaptively determined according to a size, area, shape, width, or height of the current block or the sub-blocks in the current block, an inter prediction direction of one of control point MVs of the current block, a sub-block MV, or a primary MV, the control point MVs of the current block, or a combination thereof; and
applying motion compensation to the current block using one or more reference pixels of reference sub-blocks within the primary reference block and excluding any reference pixel of reference sub-blocks outside the primary reference block, wherein the reference sub-blocks are pointed by the derived sub-block MVs,
wherein the one or more thresholds are adaptively determined to be zero or unlimited, wherein all the sub-block MVs are set equal to the primary MV if the one or more thresholds are zero, and constraining the sub-block MVs is not applied to the current block if the one or more thresholds are unlimited.