US 12,309,373 B2
Image encoding method and device, and image decoding method and device
Yinji Piao, Suwon-si (KR); Minsoo Park, Suwon-si (KR); Minwoo Park, Suwon-si (KR); Seungsoo Jeong, Suwon-si (KR); Kiho Choi, Suwon-si (KR); Narae Choi, Suwon-si (KR); Woongil Choi, Suwon-si (KR); and Anish Tamse, Suwon-si (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed on Feb. 12, 2024, as Appl. No. 18/439,082.
Application 18/439,082 is a continuation of application No. 17/532,435, filed on Nov. 22, 2021, granted, now 11,936,870.
Application 17/532,435 is a continuation of application No. PCT/KR2020/006665, filed on May 21, 2020.
Claims priority of provisional application 62/850,815, filed on May 21, 2019.
Prior Publication US 2024/0187595 A1, Jun. 6, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/129 (2014.01); H04N 19/176 (2014.01); H04N 19/18 (2014.01); H04N 19/46 (2014.01); H04N 19/96 (2014.01)
CPC H04N 19/129 (2014.11) [H04N 19/176 (2014.11); H04N 19/18 (2014.11); H04N 19/46 (2014.11); H04N 19/96 (2014.11)] 4 Claims
OG exemplary drawing
 
1. An image decoding method comprising:
determining a current transform unit in a current coding unit;
obtaining information indicating whether to apply or skip a transformation on the current transform unit;
determining whether to obtain residual data of the current transform unit by applying or skipping a transformation on the current transform unit according to the information;
when it is determined to obtain the residual data of the current transform by skipping the transformation on the current transform unit, obtaining a significant sub-block flag which indicates whether a sub-block in the current transform unit comprises at least one non-zero coefficient or not;
when the significant sub-block flag indicates that the sub-block comprises at least one non-zero coefficient, obtaining at least one of a significant coefficient flag, a sign flag, a first flag and a parity flag by decoding at least one first bin about the significant coefficient flag, the sign flag, the first flag and the parity flag based on a context model, wherein the number of the at least one first bin is equal to or smaller than a number determined based on at least one of width and height of the current transform unit;
obtaining the residual data of the current transform unit, based on at least one of a base level of a coefficient comprised in the sub-block and a remainder excluding the base level from an absolute value of the coefficient, wherein the base level is determined by using the significant coefficient flag, the first flag and the parity flag; and
obtaining a reconstruction block of the current coding unit by using the residual data of the current transform unit,
wherein:
the significant coefficient flag indicates whether the coefficient is a non-zero coefficient or not,
the first flag indicates whether the absolute value of the coefficient is greater than a predetermined value or not,
the parity flag indicates whether the coefficient is an odd number or an even number.