US 11,985,354 B2
Affine motion model restrictions reducing number of fetched reference lines during processing of one block row with enhanced interpolation filter
Timofey Mikhailovich Solovyev, Moscow (RU); Maxim Borisovitch Sychev, Moscow (RU); Huanbang Chen, Shenzhen (CN); Alexander Alexandrovich Karabutov, Moscow (RU); Roman Igorevich Chernyak, Moscow (RU); Sergey Yurievich Ikonin, Moscow (RU); Haitao Yang, Shenzhen (CN); and Elena Alexandrovna Alshina, Munich (DE)
Assigned to HUAWEI TECHNOLOGIES CO., LTD., Shenzhen (CN)
Filed by HUAWEI TECHNOLOGIES CO., LTD., Guangdong (CN)
Filed on Feb. 22, 2022, as Appl. No. 17/676,966.
Application 17/676,966 is a continuation of application No. PCT/RU2020/050257, filed on Sep. 30, 2020.
Claims priority of application No. PCT/RU2019/000690 (WO), filed on Sep. 30, 2019; and application No. PCT/RU2019/000691 (WO), filed on Sep. 30, 2019.
Prior Publication US 2022/0182678 A1, Jun. 9, 2022
Int. Cl. H04N 19/82 (2014.01); H04N 19/105 (2014.01); H04N 19/132 (2014.01); H04N 19/139 (2014.01); H04N 19/172 (2014.01); H04N 19/176 (2014.01); H04N 19/615 (2014.01); H04N 19/80 (2014.01)
CPC H04N 19/615 (2014.11) [H04N 19/105 (2014.11); H04N 19/132 (2014.11); H04N 19/139 (2014.11); H04N 19/172 (2014.11); H04N 19/176 (2014.11); H04N 19/80 (2014.11)] 14 Claims
OG exemplary drawing
 
1. A method for coding a video implemented in an encoder or a decoder, the method comprising:
determining control point motion vectors (CPMVs) for a block according to affine inter-prediction, according to a preselected affine motion model, the block being an affine block;
performing motion compensation for the block using a pixel-based motion vector field according to values of the CPMVs, upon fulfilling at least one of the following conditions:
A) the number of lines of the reference picture is less than N, where N is a predefined value and N is larger than 2; or
B) fetching of lines during processing of one sub-block is sequential, respectively, such that if for an ith line of the current block the jth line of the reference picture is fetched, then for the (i+1)th line of the current block only lines higher than j are fetched; or
C) for a predefined size of a sub-block of M×M, only one additional line is fetched for each line of the sub-block except for the first line of the sub-block;
wherein the following inequalities hold:
dVerY≥−1;
(max(0,dVerY)+|dHorY|)(W+1)+2≤N;
where dHorY is the difference of the vertical part of a motion vector between each sample in horizontal direction according to the affine motion model for the current affine block; dVerY is the difference of the vertical part of the motion vector between each sample in vertical direction according to the affine motion model for the current affine block.