US 12,464,156 B2
Method and apparatus for motion vector prediction based on subblock motion vector
Han Gao, San Diego, CA (US); Xin Zhao, San Jose, CA (US); Liang Zhao, Sunnyvale, 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 Mar. 17, 2023, as Appl. No. 18/122,823.
Claims priority of provisional application 63/408,569, filed on Sep. 21, 2022.
Prior Publication US 2024/0098299 A1, Mar. 21, 2024
Int. Cl. H04N 19/52 (2014.01); H04N 19/105 (2014.01); H04N 19/109 (2014.01); H04N 19/139 (2014.01); H04N 19/159 (2014.01); H04N 19/172 (2014.01); H04N 19/176 (2014.01); H04N 19/577 (2014.01)
CPC H04N 19/52 (2014.11) [H04N 19/105 (2014.11); H04N 19/109 (2014.11); H04N 19/139 (2014.11); H04N 19/159 (2014.11); H04N 19/172 (2014.11); H04N 19/176 (2014.11); H04N 19/577 (2014.11)] 12 Claims
OG exemplary drawing
 
1. A method for decoding a current block of a current frame in a coded video bitstream, the method comprising:
receiving, by a device comprising a memory storing instructions and a processor in communication with the memory, a coded video bitstream;
determining, by the device based on the coded video bitstream, the current block of the current frame to be inter predicted by at least one reference block of at least one reference frame;
identifying, by the device, a reference subblock motion vector (MV) of a reference subblock; and
determining, by the device based on the coded video bitstream, a current-block MV for the current block, wherein:
the reference subblock MV is determined by a local warp motion prediction mode, and, when the reference subblock MV has a higher precision than ⅛-pel, is downshifted to ⅛-pel precision to be stored as a spatial MV predictor (MVP) for the current block, and
the current-block MV is predicted by a spatial motion vector prediction (SMVP) mode based on the reference subblock MV of the reference block.