Information processing device and method

1 . An information processing device comprising:

circuitry configured to:

refer to first information about a change in a relationship of a point cloud for three-dimensional spatial regions that are independently decodable, which is stored in a file in which a bit stream of encoded data acquired by encoding the point cloud expressing an object having a three-dimensional shape is stored, and

in a case in which the first information indicates that the relationship of the point cloud is static:

generate second information about the three-dimensional spatial regions, and

extract data of tiles composing the three-dimensional spatial regions constructing the point cloud based on the second information about the three-dimensional spatial regions; and

a decoder configured to decode the extracted data,

wherein the first information is information indicating whether or not a correspondence relation between each of the three-dimensional spatial regions and information used for acquiring a respective one of the tiles is static,

wherein, based on at least some of the three-dimensional spatial regions being dynamic, the second information includes information representing a number of the three-dimensional spatial regions which are static and does not include information representing the correspondence relation for the three-dimensional spatial regions which are static, and

wherein the circuitry extracts the data of the tiles from the file based on information about the three-dimensional spatial regions that are dynamic and the second information.

2 . The information processing device according to claim 1 ,

wherein the relationship further includes a positional relation in a three-dimensional space between the three-dimensional spatial regions,

wherein the second information is static information representing a range in which the three-dimensional spatial regions are able to be present,

wherein the extraction circuitry specifies the three-dimensional spatial regions constructing the point cloud based on the information, which is static, representing the range in which the three-dimensional spatial regions are able to be present.

3 . The information processing device according to claim 2 ,

wherein the second information about the three-dimensional spatial regions further includes a correspondence relation between the three-dimensional spatial regions and the information used for acquiring the tiles, which is static, and

wherein the circuitry extracts the data of the tiles composing the three-dimensional spatial regions specified based on the static information representing the range in which the three-dimensional spatial regions are able to be present based on the second information about the three-dimensional spatial regions from the file.

4 . The information processing device according to claim 1 , wherein the information used for acquiring the tiles is-comprises identification information of the tiles.

5 . The information processing device according to claim 1 , wherein the information used for acquiring the tiles comprises is-identification information of tracks storing the data of the tiles in the file.

6 . An information processing method performed by an information processing device, the information processing method comprising:

referring to first information about a change in a relationship of a point cloud for three-dimensional spatial regions that are independently decodable, which is stored in a file in which a bit stream of encoded data acquired by encoding the point cloud expressing an object having a three-dimensional shape is stored, and, in a case in which the relationship of the point cloud, is static, extracting data of tiles composing the three-dimensional spatial regions constructing the point cloud based on second information about the three-dimensional spatial regions generated in accordance with the first information; and

decoding the extracted data,

wherein the first information is information indicating whether or not a correspondence relation between each of the three-dimensional spatial regions and information used for acquiring a respective one of the tiles is static,

wherein, based on at least some of the three-dimensional spatial regions being dynamic, the second information includes information representing a number of the three-dimensional spatial regions which are static and does not include information representing the correspondence relation for the three-dimensional spatial regions which are static, and

wherein the method further comprises extracting the data of the tiles from the file based on information about the three-dimensional spatial regions that are dynamic and the second information.