US 11,856,153 B2
Intra prediction method and device and computer-readable storage medium
Junyan Huo, Dongguan (CN); Yanzhuo Ma, Dongguan (CN); Shuai Wan, Dongguan (CN); Fuzheng Yang, Dongguan (CN); and Jinkun Guo, Dongguan (CN)
Assigned to GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD., Guangdong (CN)
Filed by GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD., Guangdong (CN)
Filed on Apr. 7, 2022, as Appl. No. 17/715,318.
Application 17/715,318 is a continuation of application No. 17/355,032, filed on Jun. 22, 2021, granted, now 11,330,299.
Application 17/355,032 is a continuation of application No. PCT/CN2019/070153, filed on Jan. 2, 2019.
Prior Publication US 2022/0232250 A1, Jul. 21, 2022
Int. Cl. H04N 19/11 (2014.01); H04N 19/176 (2014.01); H04N 19/593 (2014.01); H04N 19/136 (2014.01)
CPC H04N 19/593 (2014.11) [H04N 19/11 (2014.11); H04N 19/136 (2014.11); H04N 19/176 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method for intra prediction, applied to a decoder, the method comprising:
determining multiple neighbouring blocks of a current block;
determining first intra prediction modes of the multiple neighbouring blocks;
constructing an intra prediction mode list corresponding to the current block based on the first intra prediction modes of the multiple neighbouring blocks, in case that the first intra prediction modes are angular intra prediction modes;
determining a first intra prediction mode index of the current block based on the intra prediction mode list;
obtaining a width to height ratio of the current block, and mapping, according to the width to height ratio of the current block, the first intra prediction mode index of the current block to a second intra prediction mode index in a wide-angle intra prediction mode;
performing prediction for the current block based on a target intra prediction mode corresponding to the second intra prediction mode index of the current block, and obtaining a prediction block;
wherein in case that the width of the current block is greater than the height of the current block and width to height ratio is greater than or equal to 2, determining the second intra prediction mode index based on the following table:
 
 
 
 
 first intra second intra
 
 the width to prediction prediction
 
 height ratio mode indices mode indices
 
 
 
 W/H == 2 2, 3, 4, 5, 6, 7 67, 68, 69, 70, 71, 72
 
 W/H == 4 2 to 11 67 to 76
 
 W/H == 8 2 to 13 67 to 78
 
 W/H == 16 2 to 15 67 to 80
 
 
in case that the height of the current block is greater than the width of the current block and height to width ratio is greater than or equal to 2, determining the second intra prediction mode index based on the following table:
 
 
 
 
 the first intra the second intra
 
 the height to prediction prediction
 
 width ratio mode indices mode indices
 
 
 
 H/W == 2 61, 62, 63, 64, 65, 66 −6, −5, −4, −3, −2, −1
 
 H/W == 4 57 to 66 −10 to −1
 
 H/W == 8 55 to 66 −12 to −1
 
 H/W == 16 53 to 66 −14 to −1
 
 
wherein, in both tables, the first intra prediction mode indices are sequentially mapped to the second intra prediction mode indices one to one.