US 11,856,184 B2
Block shape adaptive intra prediction directions for quadtree-binary tree
Fabrice Leleannec, Cesson-Sevigne (FR); Fabien Racape, San Francisco, CA (US); Gagan Rath, Cesson-Sevigne (FR); and Fabrice Urban, Thorigne Fouillard (FR)
Assigned to INTERDIGITAL VC HOLDINGS, INC., Wilmington, DE (US)
Appl. No. 17/054,561
Filed by INTERDIGITAL VC HOLDINGS, INC., Wilmington, DE (US)
PCT Filed May 10, 2019, PCT No. PCT/US2019/031702
§ 371(c)(1), (2) Date Nov. 11, 2020,
PCT Pub. No. WO2019/222042, PCT Pub. Date Nov. 21, 2019.
Claims priority of application No. 18305586 (EP), filed on May 14, 2018; application No. 18305963 (EP), filed on Jul. 16, 2018; and application No. 18306075 (EP), filed on Aug. 6, 2018.
Prior Publication US 2021/0250577 A1, Aug. 12, 2021
Int. Cl. H04N 19/105 (2014.01); H04N 19/11 (2014.01); H04N 19/147 (2014.01); H04N 19/159 (2014.01); H04N 19/176 (2014.01); H04N 19/593 (2014.01); H04N 19/96 (2014.01)
CPC H04N 19/105 (2014.11) [H04N 19/11 (2014.11); H04N 19/147 (2014.11); H04N 19/159 (2014.11); H04N 19/176 (2014.11); H04N 19/593 (2014.11); H04N 19/96 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
predicting a video sample belonging to a rectangular block based on at least one sample of a neighboring block lying along a direction based on block shape of the rectangular block, wherein a greater number of prediction directions are available along a longer side of said rectangular block than along a shorter side of said rectangular block; and,
encoding the rectangular block using intra prediction based on the predicted video sample, wherein a mapping of a regular mode to a wide angle mode is performed based on a ratio of block width to block height corresponding to a prediction direction for the rectangular block being encoded and, wherein a fixed number of prediction indices are used to indicate a range of intra prediction directions, the overall number of intra prediction directions is fixed, the range of intra prediction directions being adapted to a shape of the rectangular block and a range of intra prediction directions extends beyond the prediction directions for a square block, and wherein prediction modes of neighbor blocks are mapped to a prediction mode of the rectangular block through a prediction direction index when added to a list of most probable modes, and wherein a flag is used to indicate a direction opposite to a regular mode direction, a reference array of samples above the rectangular block has length of 2 W+1 and a reference array of samples left of the rectangular block has height 2H+1, where W is a width of the rectangular block and H is a height of the rectangular block and prediction directions on the longer side of said rectangular block extend to angles ranging from 45 degrees down to −135 degrees.