Methods and Devices for Binary Entropy Coding of Point Clouds
AssigneeBlackBerry Limited
InventorSébastien Lasserre
Life of this patent
Estimating the term…
Abstract
Methods and devices for encoding or decoding a point cloud. A bit sequence signaling an occupancy pattern for sub-volumes of a volume is coded using entropy coding. For a current sub-volume, probabilities of respective entropy coders for entropy coding the occupancy pattern may be selected based on occupancy data for a plurality of neighbouring sub-volumes of the current sub-volume and on occupancy data for subdivisions of the neighbouring sub-volumes.
Claims21
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:
- for a current node associated with a sub-volume split into further sub-volumes, each further sub-volume corresponding to a child node of the current node,
- determining an occupancy pattern for the current node based on occupancy statuses of the child nodes;
- selecting one or more probabilities associated with respective entropy coders for entropy encoding the occupancy pattern, wherein the selecting is based on occupancy data for a plurality of neighbouring nodes of the current node and on occupancy data for child nodes of at least one of the plurality of neighbouring nodes;
- and
- entropy encoding the occupancy pattern based on the selected one or more probabilities, using the associated one or more entropy coders, to produce encoded data for the bitstream.
A method of decoding a bitstream of compressed point cloud data to produce a reconstructed point cloud, 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:
- for a current node associated with a sub-volume split into further sub-volumes, each further sub-volume corresponding to a child node of the current node,
- selecting one or more probabilities associated with respective entropy coders for entropy decoding the occupancy pattern, wherein the selecting is based on occupancy data for a plurality of neighbouring nodes of the current node and on occupancy data of child nodes of at least one of the plurality of neighbouring nodes;
- and
- entropy decoding the bitstream based on the selected one or more probabilities, using the one or more associated entropy coders, to produce a reconstructed occupancy pattern for the current node signaling occupancy of the child nodes.
(canceled)
Dependencies are inferred from the claim text.