Point cloud encoding method, point cloud decoding method, encoder, and decoder

A point cloud decoding apparatus, comprising:

• at least one processor;
• and
• one or more memories coupled to the at least one processor and storing instructions for execution by the at least one processor to:
• parse a bitstream to obtain a syntax element, wherein the syntax element comprises auxiliary information of a union occupancy map corresponding to a point cloud group, wherein the point cloud group comprises N frames of point clouds, wherein N≥2, wherein N is an integer, wherein each frame of the N frames of point clouds comprises one or more patches, wherein each patch of the one or more patches is associated with an occupancy map, wherein the union occupancy map corresponds to a union set of N occupancy maps of N patches from the N frames of point clouds respectively, and wherein the N patches from the N frames of point clouds have a matching relationship;
• determine auxiliary information of the N patches based on the auxiliary information that is of the union occupancy map and that is obtained through parsing;
• and
• reconstruct the N frames of point clouds based on auxiliary information of a plurality of patches in the N frames of point clouds, wherein the plurality of patches comprise the N patches.

A non-transitory computer-readable storage medium, comprising program code, wherein when the program code is run on a computer, the computer is enabled to perform the steps:

• parsing a bitstream to obtain a syntax element, wherein the syntax element comprises auxiliary information of a union occupancy map corresponding to a point cloud group, wherein the point cloud group comprises N frames of point clouds, wherein N ≥2, wherein N is an integer, wherein each frame of the N frames of point clouds comprises one or more patches, wherein each patch of the one or more patches is associated with an occupancy map, and wherein the union occupancy map corresponds to a union set of N occupancy maps of N patches from the N frames of point clouds respectively, wherein the N patches from the N frames of point clouds have a matching relationship;
• determining auxiliary information of the N patches based on the auxiliary information that is of the union occupancy map and that is obtained through parsing;
• and
• reconstructing the N frames of point clouds based on auxiliary information of a plurality of patches in the N frames of point clouds, wherein the plurality of patches comprise the N patches.