US 12,081,733 B2
Inter-image component prediction method, and image encoding and decoding method and device using same
Jae Gon Kim, Goyang-si (KR); Do Hyeon Park, Goyang-si (KR); Yong Uk Yoon, Jeju-si (KR); and Ji Hoon Do, Busan (KR)
Assigned to INTELLECTUAL DISCOVERY CO., LTD., Seoul (KR)
Appl. No. 17/291,833
Filed by INTELLECTUAL DISCOVERY CO., LTD., Seoul (KR)
PCT Filed Nov. 22, 2019, PCT No. PCT/KR2019/016195
§ 371(c)(1), (2) Date May 6, 2021,
PCT Pub. No. WO2020/106117, PCT Pub. Date May 28, 2020.
Claims priority of application No. 10-2018-0146571 (KR), filed on Nov. 23, 2018.
Prior Publication US 2021/0392321 A1, Dec. 16, 2021
Int. Cl. H04N 19/105 (2014.01); H04N 19/109 (2014.01); H04N 19/167 (2014.01); H04N 19/176 (2014.01); H04N 19/186 (2014.01); H04N 19/46 (2014.01)
CPC H04N 19/105 (2014.11) [H04N 19/109 (2014.11); H04N 19/167 (2014.11); H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/46 (2014.11)] 13 Claims
OG exemplary drawing
 
1. An image decoding method, comprising:
determining an inter-component prediction mode of a chroma component block based on an inter-component prediction mode list and predetermined index information, wherein the inter-component prediction mode list is configured with k inter-component prediction modes;
downsampling reference samples for inter-component prediction of the chroma component block based on the determined inter-component prediction mode;
classifying the downsampled reference samples into a first group and a second group, wherein the first group represents a minimum value group of first downsampled reference samples having relatively small values among the downsampled reference samples and the second group represents a maximum value group of second downsampled reference samples having relatively large values among the downsampled reference samples;
obtaining a first average value between the first downsampled reference samples in the first group and a second average value between the second downsampled reference samples in the second group;
calculating a difference between the first average value and the second average value;
deriving a parameter of a linear prediction model based on the difference between the first average value of the first group and the second average value of the second group; and
performing the inter-component prediction on the chroma component block by using the parameter of the linear prediction model,
wherein a filter for the downsampling is variably determined depending on whether a top boundary of a luma component block corresponding to the chroma component block is on a top boundary of a coding tree unit (CTU) to which the luma component block belongs.