US 12,143,646 B2
Methods and devices using direct coding in point cloud compression
David Flynn, Darmstadt (DE); and Sébastien Lasserre, Thorigné-Fouillard (FR)
Assigned to BlackBerry Limited, Waterloo (CA)
Filed by BlackBerry Limited, Waterloo (CA)
Filed on Dec. 23, 2022, as Appl. No. 18/145,908.
Application 18/145,908 is a continuation of application No. 16/955,279, granted, now 11,570,481, previously published as PCT/CA2019/050036, filed on Jan. 10, 2019.
Claims priority of application No. 18305038 (EP), filed on Jan. 18, 2018.
Prior Publication US 2023/0126256 A1, Apr. 27, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/91 (2014.01); G06T 9/00 (2006.01); G06T 9/40 (2006.01); H03M 7/30 (2006.01); H03M 7/40 (2006.01); H04N 19/96 (2014.01)
CPC H04N 19/91 (2014.11) [G06T 9/001 (2013.01); G06T 9/40 (2013.01); H03M 7/405 (2013.01); H03M 7/6094 (2013.01); H04N 19/96 (2014.11)] 18 Claims
OG exemplary drawing
 
1. A method of encoding a point cloud to generate a bitstream of compressed point cloud data, the point cloud being defined in a tree structure having a plurality of nodes having parent-child relationships and that represent the geometry of a volumetric space recursively split into sub-volumes and containing the points of the point cloud, the method comprising:
traversing the tree to entropy encode patterns of occupancy for sets of child nodes, wherein a pattern of occupancy indicates which of the sub-volumes associated with the respective child nodes contain at least one point, and wherein the traversing includes:
for a current node associated with a sub-volume,
determining that points within the sub-volume associated with the current node are eligible for direct coding based on an occupancy pattern for a parent node to the current node;
inserting a flag in the bitstream indicating the direct coding is to be used to encode the current node; and
entropy encoding positional coordinate data for at least one of the points within the sub-volume.