US 12,225,211 B2
Image encoding and decoding methods with implicit splitting
Min Yong Jeon, Seoul (KR); Dong Jin Park, Seoul (KR); Dae Yeon Kim, Seoul (KR); Sung Chang Lim, Daejeon (KR); Jung Won Kang, Daejeon (KR); Ha Hyun Lee, Seoul (KR); Jin Ho Lee, Daejeon (KR); and Hui Yong Kim, Daejeon (KR)
Assigned to Electronics And Telecommunications Research Institute, Daejeon (KR); and CHIPS & MEDIA, INC., Seoul (KR)
Appl. No. 16/493,902
Filed by ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE, Daejeon (KR); and CHIPS & MEDIA, INC., Seoul (KR)
PCT Filed Feb. 27, 2018, PCT No. PCT/KR2018/002416
§ 371(c)(1), (2) Date Sep. 13, 2019,
PCT Pub. No. WO2018/182184, PCT Pub. Date Oct. 4, 2018.
Claims priority of application No. 10-2017-0042269 (KR), filed on Mar. 31, 2017.
Prior Publication US 2020/0029082 A1, Jan. 23, 2020
Int. Cl. H04N 19/176 (2014.01); H04N 19/426 (2014.01); H04N 19/503 (2014.01); H04N 19/96 (2014.01); G06T 9/40 (2006.01); H04N 19/119 (2014.01)
CPC H04N 19/176 (2014.11) [H04N 19/426 (2014.11); H04N 19/503 (2014.11); H04N 19/96 (2014.11); G06T 9/40 (2013.01); H04N 19/119 (2014.11)] 9 Claims
OG exemplary drawing
 
1. An image decoding method, comprising:
obtaining a current coding tree unit (CTU) of a first size configuring a current picture;
determining whether to implicitly divide the current coding tree unit;
dividing the current coding tree unit into one or more coding units (CUs) based on the determination;
obtaining, from a bitstream, division information for a current coding unit among the one or more coding units; and
dividing and decoding the current coding unit,
wherein in case the current coding tree unit is determined to be implicitly divided, the dividing the current coding tree unit performs an implicit dividing process without the division information recursively until the current coding tree unit of the first size is divided into a plurality of coding units of a second size, the implicit dividing process without the division information performed by using a quadtree splitting method with skipping decoding of division information, the implicit dividing process without the division information is performed without considering the division information,
wherein the dividing and decoding the current coding unit divides the current coding unit by using a dividing process with the division information,
wherein any splitting method other than the quadtree splitting method is excluded for the implicit dividing process without the division information,
wherein the dividing process with the division information uses a selected splitting method among a multiple splitting methods including the quadtree splitting method and a binary tree splitting method,
wherein the dividing and decoding the current coding unit is performed by using dequantization corresponding to at least one quantization parameter, the at least one quantization parameter decided by using a quantization parameter predictor,
wherein the quantization parameter predictor is decided by considering a coding unit order which is decided by decoding or encoding the image, and
wherein the quantization parameter predictor of the current coding unit is generated by searching a left coding unit and a top coding unit of the current coding unit, for one or two valid quantization parameters,
wherein the coding unit is decoded by:
determining a transform matrix, and
performing inverse-transforming using the determined transform matrix,
wherein, in case the coding unit is intra predicted, the transform matrix is determined based on directionality of an intra prediction mode.