Multiple lists for blocked based weighting factors

A method for encoding video data, the method comprising:

• receiving video data that includes a current block of a current image frame;
• when the current block is to be predicted in a weighted bi-prediction (WBP) mode:
• determining that the current block is associated with two bi-prediction blocks including a first prediction block and a second prediction block;
• identifying a plurality of distinct weighting factor lists including at least a first list and a second list, wherein the first list has all positive weighting factors, wherein the second list has at least one negative weighting factor, and wherein the first list has at least one weighting factor distinct from respective weighting factors in the second list;
• selecting one of the plurality of weighing factor lists based on a predefined criterion;
• and
• identifying a first weighting factor from the selected one of the plurality of weighing factor lists;
• and
• encoding the current image frame including encoding the current block by combining the first prediction block and the second prediction block using the first weighting factor.

A non-transitory computer-readable storage medium storing a video bitstream that is generated by a video encoding method, the video encoding method comprising:

• receiving video data that includes a current block of a current image frame;
• when the current block is to be predicted in a weighted bi-prediction (WBP) mode:
• determining that the current block is associated with two bi-prediction blocks including a first prediction block and a second prediction block;
• identifying a plurality of distinct weighting factor lists including at least a first list and a second list, wherein the first list has all positive weighting factors, wherein the second list has at least one negative weighting factor, and wherein the first list has at least one weighting factor distinct from respective weighting factors in the second list;
• selecting one of the plurality of weighing factor lists based on a predefined criterion;
• and
• identifying a first weighting factor from the selected one of the plurality of weighing factor lists;
• and
• encoding the current image frame including encoding the current block by combining the first prediction block and the second prediction block using the first weighting factor.