Method and apparatus using boundary matching for overlapped block motion compensation in video coding system

An apparatus for video coding, the apparatus comprising one or more electronics or processors arranged to:

• receive input data associated with a current block, wherein the input data comprise pixel data for the current block to be encoded at an encoder side or prediction residual data associated with the current block to be decoded at a decoder side;
• determine a set of MC (Motion Compensation) candidates with each MC candidate comprising predicted samples for coding boundary pixels of the current block, wherein the set of MC candidates comprises a first candidate, and wherein the first candidate corresponds to a weighted sum of first predicted pixels generated according to first motion information of the current block and second predicted pixels generated according to second motion information of a neighbouring boundary block of the current block;
• determine boundary matching costs associated with the set of MC candidates, wherein each of the boundary matching costs is determined, for one target candidate of the set of MC candidates, between reconstructed or predicted samples of the current block determined according to said one target candidate and neighbouring reconstructed samples of one or more neighbouring blocks of the current block;
• determine a final candidate from the set of MC candidates based on the boundary matching costs;
• and
• encode or decode the current block using the final candidate.