US 12,238,317 B2
Block based weighting factor for joint motion vector difference coding mode
Liang Zhao, Sunnyvale, CA (US); Xin Zhao, Santa Clara, CA (US); Han Gao, San Diego, CA (US); and Shan Liu, San Jose, CA (US)
Assigned to Tencent America LLC, Palo Alto, CA (US)
Filed by Tencent America LLC, Palo Alto, CA (US)
Filed on Jun. 28, 2023, as Appl. No. 18/215,704.
Claims priority of provisional application 63/451,807, filed on Mar. 13, 2023.
Prior Publication US 2024/0314343 A1, Sep. 19, 2024
Int. Cl. H04N 19/44 (2014.01); H04N 19/105 (2014.01); H04N 19/137 (2014.01); H04N 19/176 (2014.01)
CPC H04N 19/44 (2014.11) [H04N 19/105 (2014.11); H04N 19/137 (2014.11); H04N 19/176 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method of video decoding in a video coder, the method comprising:
receiving a bitstream including a frame, coding information for a block in the frame indicating that the block is coded with a joint motion vector difference (JMVD) coding mode and a compound weighted prediction mode, the coding information further including scaling factor information of the JMVD coding mode;
in response to the scaling factor information indicating that each of scaling factors of components of at least one MVD associated with at least one respective reference frame of the block is a pre-defined scaling factor, determining a weighting factor of the compound weighted prediction mode based on a list of weighting factors, the list being signaled in the bitstream;
in response to the scaling factor information indicating that at least one of the scaling factors is different from the pre-defined scaling factor, determining the weighting factor of the compound weighted prediction mode based on a subset of the list of weighting factors, only the subset of the list being signaled in the bitstream;
determining, using the JMVD coding mode, motion information associated with respective reference frames of the block based on the scaling factors of the components of the at least one MVD associated with the at least one respective reference frame of the block, the reference frames of the block including the at least one respective reference frame; and
reconstructing, using the compound weighted prediction mode, the block based on the motion information associated with the respective reference frames of the block and the determined weighting factor.