US 12,457,322 B2
Method and apparatus for encoding/decoding image in intra prediction and recording medium for storing bitstream
Sung Chang Lim, Daejeon (KR); Jung Won Kang, Daejeon (KR); Ha Hyun Lee, Seoul (KR); Jin Ho Lee, Daejeon (KR); Hui Yong Kim, Daejeon (KR); and Dae Yeon Kim, Seoul (KR)
Assigned to Electronics and Telecommunications Research Institute, Daejeon (KR); and CHIPS & MEDIA, INC, Seoul (KR)
Appl. No. 17/608,399
Filed by Electronics and Telecommunications Research Institute, Daejeon (KR); and CHIPS & MEDIA, INC, Seoul (KR)
PCT Filed Apr. 29, 2020, PCT No. PCT/KR2020/005750
§ 371(c)(1), (2) Date Nov. 2, 2021,
PCT Pub. No. WO2020/226359, PCT Pub. Date Nov. 12, 2020.
Claims priority of application No. 10-2019-0052145 (KR), filed on May 3, 2019; application No. 10-2019-0073909 (KR), filed on Jun. 21, 2019; application No. 10-2019-0075285 (KR), filed on Jun. 24, 2019; application No. 10-2019-0084156 (KR), filed on Jul. 12, 2019; application No. 10-2019-0084793 (KR), filed on Jul. 12, 2019; application No. 10-2019-0117079 (KR), filed on Sep. 23, 2019; and application No. 10-2020-0004039 (KR), filed on Jan. 13, 2020.
Prior Publication US 2022/0279161 A1, Sep. 1, 2022
Int. Cl. H04N 19/105 (2014.01); H04N 19/119 (2014.01); H04N 19/132 (2014.01); H04N 19/169 (2014.01); H04N 19/176 (2014.01); H04N 19/186 (2014.01); H04N 19/80 (2014.01)
CPC H04N 19/105 (2014.11) [H04N 19/119 (2014.11); H04N 19/132 (2014.11); H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/1883 (2014.11); H04N 19/80 (2014.11)] 16 Claims
OG exemplary drawing
 
1. A method of decoding an image, the method comprising:
determining an intra prediction mode of a current block; and
generating a prediction block of the current block, by performing prediction based on the intra prediction mode,
wherein when the current block is a chroma block and the intra prediction mode of the current block is a cross-component prediction mode, the generating the prediction block of the current block includes:
generating neighboring samples of a luma block corresponding to the current block;
performing down-sampling with respect to the neighboring samples of the luma block by applying at least one filter to neighboring samples at specific locations among the neighboring samples of the luma block;
deriving a cross-component parameter based on the down-sampled neighboring samples; and
generating the prediction block of the current block based on the cross-component parameter,
wherein the neighboring samples of the luma block includes at least one of top neighboring samples or left neighboring samples,
wherein a number of samples used in a filter used for down-sampling of the top neighboring samples varies depending on whether a top boundary of the current block is a coding tree unit (CTU) boundary or not, and
wherein an interval between the specific locations is determined based on a type of the cross-component prediction mode and the number of available neighboring samples of the current block.