US 12,341,949 B2
Image encoding/decoding method and device
Ki Baek Kim, Daejeon (KR)
Assigned to B1 INSTITUTE OF IMAGE TECHNOLOGY, INC., Seoul (KR)
Filed by B1 INSTITUTE OF IMAGE TECHNOLOGY, INC., Seoul (KR)
Filed on Jul. 27, 2022, as Appl. No. 17/874,536.
Application 17/874,536 is a division of application No. 16/980,680, granted, now 11,438,577, previously published as PCT/KR2019/003443, filed on Mar. 25, 2019.
Claims priority of application No. 10-2018-0034174 (KR), filed on Mar. 25, 2018; application No. 10-2018-0034882 (KR), filed on Mar. 27, 2018; and application No. 10-2018-0085679 (KR), filed on Jul. 24, 2018.
Prior Publication US 2023/0026091 A1, Jan. 26, 2023
Int. Cl. H04N 19/00 (2014.01); H04N 19/105 (2014.01); H04N 19/176 (2014.01); H04N 19/186 (2014.01); H04N 19/30 (2014.01)
CPC H04N 19/105 (2014.11) [H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/30 (2014.11)] 7 Claims
OG exemplary drawing
 
1. An image decoding method performed by an image decoding apparatus, the method comprising:
obtaining, from a bitstream, a first flag specifying whether to use an affine model:
determining the affine model for a current block among a 4-parameter affine model and a 6-parameter affine model based on a second flag signaled through the bitstream;
deriving a plurality of control point vectors for the current block based on the determined affine model;
deriving a motion vector for the current block based on the plurality of control point vectors; and
generating a prediction block for the current block by performing inter-prediction based on the motion vector for the current block,
wherein the second flag indicates whether to use the 4-parameter affine model or the 6-parameter affine model,
wherein a number of the plurality of control point vectors is determined based on both the first flag and the second flag, and
wherein the plurality of the control point vectors are derived further based on whether a position of the current block is located on a boundary of a coding tree unit (CTU).