	US 11,902,550 B2
	Pruning method for history-based affine parameters
Kai Zhang, San Diego, CA (US); Li Zhang, San Diego, CA (US); Hongbin Liu, Beijing (CN); Jizheng Xu, San Diego, CA (US); and Yue Wang, Beijing (CN)
Assigned to BEIJING BYTEDANCE NETWORK TECHNOLOGY CO., LTD, Beijing (CN); and BYTEDANCE INC., Los Angeles, CA (US)
Filed by Beijing Bytedance Network Technology Co., Ltd., Beijing (CN); and Bytedance Inc., Los Angeles, CA (US)
Filed on May 13, 2021, as Appl. No. 17/319,950.
Application 17/319,950 is a continuation of application No. PCT/CN2019/119279, filed on Nov. 18, 2019.
Claims priority of application No. PCT/CN2018/115935 (WO), filed on Nov. 16, 2018; application No. PCT/CN2019/070003 (WO), filed on Jan. 1, 2019; application No. PCT/CN2019/071221 (WO), filed on Jan. 10, 2019; application No. PCT/CN2019/074600 (WO), filed on Feb. 2, 2019; and application No. PCT/CN2019/075867 (WO), filed on Feb. 22, 2019.
Prior Publication US 2021/0266591 A1, Aug. 26, 2021
Int. Cl. H04N 19/423 (2014.01); H04N 19/105 (2014.01); H04N 19/159 (2014.01); H04N 19/176 (2014.01); H04N 19/137 (2014.01); H04N 19/30 (2014.01); H04N 19/513 (2014.01); H04N 19/167 (2014.01); H04N 19/196 (2014.01); H04N 19/52 (2014.01)

CPC H04N 19/423 (2014.11) [H04N 19/105 (2014.11); H04N 19/137 (2014.11); H04N 19/159 (2014.11); H04N 19/167 (2014.11); H04N 19/176 (2014.11); H04N 19/196 (2014.11); H04N 19/30 (2014.11); H04N 19/513 (2014.11); H04N 19/52 (2014.11)]

17 Claims

1. A method of processing video data, comprising:

deriving, for a conversion between a current block of a video and a bitstream of the video, a first set of affine parameters associated with affine model for the current block;

comparing the first set of affine parameters to one or more sets of affine parameters stored in a buffer for storing affine parameters to make a determination whether the first set of affine parameters is same or similar to at least one set of affine parameters of the one or more sets of affine parameters; and

deciding whether or how to update the buffer for storing affine parameters based on the determination,

wherein, in response to the determination indicating that the first set of affine parameters is not same or similar to at least one set of affine parameters stored in the buffer, storing the first set of affine parameters in the buffer,

wherein the first set of affine parameters comprises variables a, b, c or d, or variables a, b, c, d, e, f,

e=mv₀^h, f=mv₀^v, or (e, f)=(mv_x, mv_y), where (mv_x, mv_y) is any motion vector used for coding a first block, wherein (mv^h₀, mv^v₀) is a motion vector of a top-left corner control point, (mv^h₁, m^v₁) is a motion vector of a top-right corner control point, and (mv^h₂, mv^v₂) is a motion vector of a bottom-left corner control point, and wherein w and h are width and height of the current block, respectively.