Point cloud coding and decoding methods, coder, decoder and storage medium

A point cloud data decoding apparatus, comprising:

• at least one memory configured to store program code;
• and
• at least one processor configured to access the at least one memory and operate according to the program code, the program code comprising:
• decoding code configured to cause at least one of the at least one processor to decode a first code stream of a point cloud, to obtain a residual value of first information of each point in the point cloud, the first information comprising at least one of geometry information and attribute information, wherein the first code stream of the point cloud is obtained by coding the residual value of the first information of each point in the point cloud based on an arrangement sequence of points in a prediction tree of the point cloud, the prediction tree of the point cloud is obtained by sorting the points in the point cloud according to a target sorting method, the target sorting method comprises at least two of a first sorting method, a second sorting method and a third sorting method, the first sorting method being a sorting method based on original coordinate information of the points, the second sorting method being a sorting method based on the sizes of codewords corresponding to the points, and the third sorting method being a sorting method based on the sizes of distances between two points, and the target sorting method sequentially applies the at least two sorting methods such that a first method of the at least two sorting methods is applied to the point cloud, and a second method of the at least two sorting methods is applied to an output of the first method to produce the prediction tree;
• acquiring code configured to cause at least one of the at least one processor to acquire the first information of a starting point in the prediction tree;
• and
• reconstruction code configured to cause at least one of the at least one processor to sequentially decode, according to the arrangement sequence of the points of the point cloud in the prediction tree, the points in the point cloud based on the first information of the starting point and the residual value of the first information of each point in the point cloud, to obtain a reconstruction value of the first information of the point cloud.

A non-transitory computer-readable storage medium, storing computer code which, when executed by at least one processor, causes the at least one processor to at least:

• decode a first code stream of a point cloud, to obtain a residual value of first information of each point in the point cloud, the first information comprising at least one of geometry information and attribute information,
• wherein the first code stream of the point cloud is obtained by coding the residual value of the first information of each point in the point cloud based on an arrangement sequence of points in a prediction tree, the prediction tree of the point cloud is obtained by sorting the points in the point cloud according to a target sorting method, the target sorting method comprises at least two of a first sorting method, a second sorting method and a third sorting method, the first sorting method being a sorting method based on original coordinate information of the points, the second sorting method being a sorting method based on sizes of codewords corresponding to the points, and the third sorting method being a sorting method based on the sizes of distances between two points, and the target sorting method sequentially applies the at least two sorting methods such that a first method of the at least two sorting methods is applied to the point cloud, and a second method of the at least two sorting methods is applied to an output of the first method to produce the prediction tree;
• acquire the first information of a starting point in the prediction tree;
• and
• sequentially decode, according to the arrangement sequence of the points of the point cloud in the prediction tree, the points in the point cloud based on the first information of the starting point and the residual value of the first information of each point in the point cloud, to obtain a reconstruction value of the first information of the point cloud.