Patent ID: 11861869
Assignee: BLACKBERRY LIMITED
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 10:
11. A method of decoding a bitstream of compressed occupancy data for a point cloud to produce a reconstructed point cloud, wherein occupancy of sub-volumes of a volume is indicated using a bit sequence with each bit of the bit sequence indicating occupancy of a respective sub-volume in a scan order within the volume, and wherein a volume has a plurality of neighbouring volumes, a pattern of occupancy of the neighbouring volumes being a neighbour configuration, the method comprising:
for at least one bit in the bit sequence of the volume,
determining that a context reduction condition is met and, on that basis, selecting a reduced context set that contains fewer contexts than the product of a count of neighbour configurations and a number of previously-coded bits in the sequence;
selecting, for coding said at least one bit, a context from the reduced context set based on an occupancy status of at least some of the neighbouring volumes and at least one previously-coded bit of the bit sequence; and
entropy decoding said at least one bit based on the selected context using a binary entropy decoder to produce a reconstructed bit from the bitstream.