Information processing device and method

Abstract

The present disclosure relates to an information processing device and method that make it possible to suppress an increase in reproduction processing load. First information that relates to a change in a relationship regarding an independently decodable three-dimensional spatial region of a point cloud is generated, said point cloud representing an object that has a three-dimensional shape. Second information that relates to the three-dimensional spatial region is generated in accordance with the first information. A file that stores the first information, the second information, and a bitstream of encoded data in which the point cloud is encoded is generated. The first information that is stored in the file is referenced, and if the aforementioned relationship is static, then on the basis of the second information, tile data constituting the three-dimensional spatial region from which the point cloud is constructed is extracted and decoded. The present disclosure can, for example, be applied to an information processing device or an information processing method.

Description

[Technical Field]

[0001] The present disclosure relates to an information processing device and method, and more particularly to an information processing device and method that are capable of suppressing an increase in the load of playback processing. [Background technology]

[0002] Conventionally, a point cloud, which is a collection of points having position information and attribute information (e.g., color, reflectance, etc.) in three-dimensional space, is encoded by separating it into geometry that indicates the three-dimensional shape and attributes that indicate the attribute information. G-PCC (Geometry-based Point Cloud Compression) is currently being standardized in MPEG-I Part 9 (ISO / IEC (International Organization for Standardization / International Electrotechnical Commission) 23090-9) (see, for example, Non-Patent Document 1).

[0003] There is also the International Organization for Standardization Base Media File Format (ISOBMFF), which is a file container specification of the Moving Picture Experts Group-4 (MPEG-4), an international standard technology for video compression (see, for example, Non-Patent Document 2).

[0004] Furthermore, in order to improve the efficiency of playback processing from local storage and network distribution of the G-PCC bitstream, which is a bitstream of coded data coded with this G-PCC, a method of storing the G-PCC bitstream in an ISOBMFF file is currently being standardized in MPEG-I Part 18 (ISO / IEC 23090-18) (see, for example, Non-Patent Document 3).

[0005] The G-PCC file storing the G-PCC bitstream defined in Non-Patent Document 3 has a structure for decoding by partial access based on 3D spatial information. Partial access means accessing (extracting data from a file) a partial point cloud, which is a part of the object represented by the point cloud (i.e., a part of the point cloud data). In particular, in distribution use cases, using such partial access makes it possible to distribute data for each track that stores the partial point cloud (i.e., to realize adaptive distribution), which is useful for suppressing increases in processing load and bandwidth load.

[0006] In this G-PCC file, a 3D spatial region can be defined as such a partial point cloud. This 3D spatial region is composed of one or more tiles. A tile is an independently decodable data unit of a point cloud. The G-PCC file manages the tiles that make up the 3D spatial region. The G-PCC file also manages which tile's data is stored in which track. In other words, the 3D spatial region is linked to the track that stores that data via the tile. Therefore, during partial access, based on this management, the tiles that make up the desired 3D spatial region are identified, the track that stores the data for that tile is identified, and the data for the desired 3D spatial region is extracted from that track.

[0007] The position, size, shape, orientation, number, etc. of objects represented by a point cloud can change over time (can be dynamic). Therefore, the 3D spatial region and the tiles that make up that 3D spatial region can also change over time (can be dynamic). Furthermore, the tiles stored in a track can also change over time (can be dynamic). Therefore, in a G-PCC file, information such as the 3D spatial region, the tiles that make up the 3D spatial region, and the tiles stored in the track are managed as dynamic information. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] "Information technology - MPEG-I (Coded Representation of Immersive Media) - Part 9: Geometry-based Point Cloud Compression", SO / IEC 23090-9:2020(E), 2020 / 11 / 28 [Non-patent document 2] "Information technology - Coding of audio-visual objects - Part 12:ISO base media file format", ISO / IEC 14496-12, 2015-02-20 [Non-patent document 3] Sejin Oh, Ryohei Takahashi, Youngkwon Lim, "Text of ISO / IEC DIS 23090-18 Carriage of Geometry-based Point Cloud Compression Data", ISO / IEC JTC 1 / SC 29 / WG 03 N0075, 2020-11-02 Summary of the Invention [Problem to be solved by the invention]

[0009] However, in the method described in Non-Patent Document 3, the 3D spatial region, the tiles that make up the 3D spatial region, the tiles stored in the track, etc. may change for each frame. Therefore, when performing partial access, it is necessary to check the track that stores the data of the desired 3D spatial region (the data of the tiles that make up the 3D spatial region) for each frame. This may increase the load of playback processing for content that uses such point clouds.

[0010] The present disclosure has been made in consideration of such circumstances, and aims to make it possible to suppress an increase in the load of the regeneration process. [Means for solving the problem]

[0011] An information processing device according to one aspect of the present technology is provided that generates an independently decodable 3D spatial region of a point cloud representing an object of 3D shape. and whether the correspondence between the identification information of the track storing the data of the tiles of the point cloud and the three-dimensional spatial region is static. a first information generating unit that generates first information; If the above is true, the dynamic The information processing device includes a second information generation unit that generates second information regarding the three-dimensional spatial region, and a file generation unit that generates a file that stores a bit stream of encoded data in which the point cloud is encoded, the first information, and the second information.

[0012] An information processing method according to one aspect of the present technology includes: and whether the correspondence between the identification information of the track storing the data of the tiles of the point cloud and the three-dimensional spatial region is static. generating first information, If the above is true, the dynamic An information processing method that generates second information about the three-dimensional spatial region, and generates a bit stream of encoded data in which the point cloud is encoded, the first information, and a file that stores the second information.

[0013] Another aspect of the present technology is an information processing device that includes a point cloud representing an object of a three-dimensional shape. of Independently decodable 3D spatial regions and whether the correspondence between the identification information of the track storing the data of the tiles of the point cloud and the three-dimensional spatial region is static. First information If is true, then the dynamic Second information regarding the three-dimensional spatial region Information indicating the correspondence relationship that is not included in Based on The aforementioned The information processing device includes an extraction unit that extracts tile data, and a decoding unit that decodes the extracted data.

[0014] Another aspect of the information processing method of the present technology is to generate a point cloud representing an object of a three-dimensional shape. of Independently decodable 3D spatial regions and whether the correspondence between the identification information of the track storing the data of the tiles of the point cloud and the three-dimensional spatial region is static. First information If is true, then the dynamic Second information regarding the three-dimensional spatial region Information indicating the correspondence relationship that is not included in Based on The aforementioned The information processing method extracts tile data and decodes the extracted data. According to yet another aspect of the present technology, an information processing device includes a first information generation unit that generates first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and the correspondence between the three-dimensional spatial region and identification information of a track that stores tile data of the point cloud are static; a second information generation unit that generates, if the first information is true, second information indicating the three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static; and a file generation unit that generates a file that stores a bit stream of encoded data obtained by encoding the point cloud, the first information, and the second information. An information processing method according to yet another aspect of the present technology is an information processing method that generates first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and the correspondence between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region are static, and if the first information is true, generates second information indicating the three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static, and generates a bit stream of encoded data in which the point cloud is encoded, the first information, and a file storing the first information and the second information. According to yet another aspect of the present technology, an information processing device includes an extraction unit that extracts data of the tile based on second information indicating a three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static when first information indicating a spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and a correspondence between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region is true, and a decoding unit that decodes the extracted data. An information processing method according to yet another aspect of the present technology is an information processing method that, when first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and the correspondence between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region are static is true, extracts data of the tile based on second information indicating the three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static, and decodes the extracted data.

[0015] In one aspect of the present technology, an information processing device and method include: Indicates whether the spatial relationship between the tile data of the point cloud and the track identification information storing the tile data of the point cloud and the correspondence between the tile data and the 3D spatial region is static. First information is generated, and the first information If this is true, the dynamic Second information about the three-dimensional spatial region is generated, and a file is generated that stores a bitstream of encoded data in which the point cloud is encoded, the first information, and the second information.

[0016] In another aspect of the present technology, an information processing device and a method include: of Independently decodable 3D spatial regions Indicates whether the spatial relationship between the tile data of the point cloud and the track identification information storing the tile data of the point cloud and the correspondence between the tile data and the 3D spatial region is static. The first information is If true, the dynamic Second information about the 3D spatial region Information indicating the correspondence that is not included in Based on the The data for the tile is extracted and the extracted data is decoded. In an information processing device and method according to yet another aspect of the present technology, first information is generated that indicates whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape, and the correspondence between the identification information of a track storing tile data of the point cloud and the three-dimensional spatial region, are static; if the first information is true, second information is generated that indicates a three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static; and a bit stream of encoded data into which the point cloud is encoded, the first information, and the second information are stored in a file. In an information processing device and method according to yet another aspect of the present technology, when first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and the correspondence between the identification information of a track storing tile data of the point cloud and the three-dimensional spatial region is static is true, data of the tile is extracted based on second information indicating a three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static, and the extracted data is decoded. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram illustrating an overview of G-PCC. [Figure 2] FIG. 10 is a diagram illustrating partial access. [Figure 3] A diagram showing an example of the structure of a G-PCC bitstream. [Figure 4] FIG. 10 is a diagram illustrating an example of tile inventory syntax. [Figure 5] FIG. 10 is a diagram showing an example of the structure of a G-PCC file. [Figure 6] FIG. 10 is a diagram showing an example of the track structure of a G-PCC file. [Figure 7] FIG. 10 is a diagram showing an example of the track structure of a G-PCC file. [Figure 8] FIG. 10 is a diagram showing an example of a GPCCSpatialRegionInfoBox. [Figure 9] FIG. 10 is a diagram showing an example of a GPCCTileSampleEntry. [Figure 10] FIG. 1 is a diagram illustrating an example of a 3D spatial region. [Figure 11] FIG. 10 is a diagram showing an example of a GPCCSpatialRegionInfoBox. [Figure 12] FIG. 10 is a diagram showing an example of a 3DSpatialRegionStruct. [Figure 13] 10A and 10B are diagrams illustrating an example of information transmission based on a change in the relationship between 3D spatial regions in the time direction. [Figure 14] FIG. 1 is a diagram illustrating an example of a 3D bounding space. [Figure 15] FIG. 1 is a diagram illustrating an example of the spatial positional relationship of a 3D spatial region. [Figure 16]FIG. 10 is a diagram showing an example of DynamicGPCC3DSpatialRegionSampleEntry. [Figure 17] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 18] FIG. 10 is a diagram illustrating an example of a 3DBoundingSpaceStruct. [Figure 19] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 20] FIG. 10 is a diagram showing an example of DynamicGPCC3DSpatialRegionSampleEntry. [Figure 21] FIG. 1 is a diagram illustrating an example of a 3D spatial region. [Figure 22] FIG. 10 is a diagram showing an example of a 3DSpatialRegionStruct. [Figure 23] FIG. 1 is a diagram illustrating an example of a 3D spatial region. [Figure 24] FIG. 10 is a diagram showing an example of DynamicGPCC3DSpatialRegionSampleEntry. [Figure 25] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 26] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 27] FIG. 10 is a diagram showing an example of DynamicGPCC3DSpatialRegionSampleEntry. [Figure 28] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 29] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 30] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 31]FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 32] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 33] FIG. 10 is a diagram illustrating an example of a DynamicGPCC3DSpatialRegionSample. [Figure 34] FIG. 10 is a diagram showing an example of DynamicGPCC3DSpatialRegionSampleEntry. [Figure 35] FIG. 10 is a diagram showing examples of elements of the GPCCSpatialRegions descriptor. [Figure 36] FIG. 10 is a diagram illustrating an example of the configuration of a Matryoshka media container. [Figure 37] FIG. 2 is a block diagram illustrating an example of the main configuration of a file generation device. [Figure 38] 10 is a flowchart illustrating an example of the flow of a file generation process. [Figure 39] FIG. 2 is a block diagram illustrating an example of the main configuration of a decoding device. [Figure 40] FIG. 2 is a block diagram showing an example of the main configuration of a playback processing unit. [Figure 41] 10 is a flowchart showing an example of the flow of a playback process. [Figure 42] FIG. 1 is a block diagram illustrating an example of the main configuration of a computer. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, modes for carrying out the present disclosure (hereinafter referred to as embodiments) will be described in the following order. 1. Dynamic 3D spatial region 2. Information transmission based on temporal changes in relationships in 3D spatial regions 3. Information transmission using MPD 4. Information Transmission Using Matryoshka Media Container 5. First embodiment (file generation device) 6. Second embodiment (playback device) 7. Additional Notes

[0019] <1. Dynamic 3D spatial region> <1-1. Literature supporting technical content and terminology> The scope of disclosure of the present technology includes not only the contents described in the embodiments but also the contents described in the following non-patent documents that were publicly known at the time of filing, as well as the contents of other documents referenced in the following non-patent documents.

[0020] Non-patent document 1: (mentioned above) Non-patent document 2: (mentioned above) Non-patent document 3: (mentioned above) Non-patent document 4: https: / / www.matroska.org / index.html

[0021] In other words, the contents of the above-mentioned non-patent documents and the contents of other documents referenced in the above-mentioned non-patent documents are also used as the basis for determining the support requirements.

[0022] <1-2. Point Cloud> Previously, there was 3D data such as point clouds that represent three-dimensional structures using point position information and attribute information.

[0023] For example, in the case of a point cloud, a three-dimensional structure (a three-dimensional object) is represented as a collection of many points. A point cloud is composed of position information (also called geometry) and attribute information (also called attribute) for each point. Attributes can include any information. For example, color information, reflectance information, normal information, etc. for each point may be included in the attributes. In this way, point clouds have a relatively simple data structure, and by using a sufficient number of points, they can represent any three-dimensional structure with sufficient accuracy.

[0024] <1-3. Overview of G-PCC> Non-Patent Document 1 discloses an encoding technology called Geometry-based Point Cloud Compression (G-PCC), which encodes point clouds by separating them into geometry and attributes. G-PCC is currently being standardized in MPEG-I Part 9 (ISO / IEC 23090-9).

[0025] For example, octree encoding is used to compress geometry. Octree encoding is an encoding method that converts the data structure of geometry into an octree as shown on the right side of Figure 1 and encodes it.

[0026] In this case, geometry is represented using voxels, which are three-dimensional regions of rectangular parallelepiped shape (including cubic shapes) with a hierarchical structure as shown on the left side of Figure 1. In other words, the presence or absence of a point is represented for each voxel. Voxels that contain points are divided, and the presence or absence of the point is represented in the smaller regions (lower voxels) after the division. This division is repeated recursively for voxels that contain points down to the lowest layer, forming a hierarchical structure of voxels.

[0027] An octree represents such a voxel representation (whether or not each voxel has a point) as an octree, as shown on the right side of Figure 1. Each node of the octree corresponds to a voxel in the voxel representation. For example, a node corresponding to a voxel where a point exists is represented as a value of "1," and a node corresponding to a voxel where no point exists is represented as a value of "0." A child node (a node one level below) is formed for a node corresponding to a voxel where a point exists (a node with a value of "1").

[0028] The bit stream of coded data generated by coding geometry as described above is also called a geometry bit stream.

[0029] Attribute compression is performed using techniques such as Predicting Weight Lifting, Region Adaptive Hierarchical Transform (RAHT), or Fix Weight Lifting. The bitstream of coded data generated by coding attributes is also called an attribute bitstream. A bitstream that combines a geometry bitstream and an attribute bitstream is also called a G-PCC bitstream.

[0030] <1-4.Tiles> The G-PCC bitstream can have a partial access structure that allows some point bitstreams to be decoded and played back independently of others. In a point cloud with this partial access structure, tiles and slices are data units that can be decoded and played back independently (independently accessible).

[0031] As shown in A of FIG. 2, a bounding box 21 is set so as to enclose a three-dimensional object 20. A tile 22 is a rectangular parallelepiped (including a cubic) area within the bounding box 21. As shown in B of FIG. 2, a slice 24 is a set of points within the tile 23. Points may overlap between slices (i.e., one point may belong to multiple slices). A tile is made up of one or more slices (1 tile = Y slice(s)).

[0032] A point cloud at a certain time is called a point cloud frame. This frame is a data unit equivalent to a frame in a 2D video image. A point cloud frame is composed of one or more tiles (1 point cloud frame = X tile(s)).

[0033] <1-5. G-PCC bitstream with partial access structure> Non-Patent Document 1 shows an example of the main structure (also called partial access structure) of a G-PCC bitstream that encodes such a point cloud that allows partial access. An example of this structure is shown in Figure 3. That is, the G-PCC bitstream shown in Figure 3 has a partial access structure, and a part of it can be extracted and decoded independently of the rest.

[0034] In Figure 3, each square represents one Type-length-value encapsulation structure (tlv_encapsulation()). As shown in Figure 3, the G-PCC bitstream has a Sequence Parameter Set (SPS), a Geometry Parameter Set (GPS), an Attribute Parameter Set (APS(s)), a Tile Inventory, a Geometry Data Unit, and an Attribute Data Unit.

[0035] A sequence parameter set is a parameter set that has parameters related to the entire sequence. A geometry parameter set is a parameter set that has parameters related to geometry. An attribute parameter set is a parameter set that has parameters related to attributes. There may be multiple geometry parameter sets and attribute parameter sets. The geometry parameter sets and attribute parameter sets may differ on a slice-by-slice basis (they can be set on a slice-by-slice basis).

[0036] The tile inventory manages information about tiles. Figure 4 shows an example of the syntax of the tile inventory. As shown in Figure 4, the tile inventory stores, for each tile, tile identification information (tile_id) for identifying the tile, information about the tile's position and size (tile_bounding_box_offset_xyz, tile_bounding_box_size_xyz), and the like. The tile inventory is variable on a frame-by-frame basis (it can be set on a frame-by-frame basis).

[0037] A data unit is a unit of data that can be extracted independently of others. A geometry data unit is a data unit of geometry. An attribute data unit is a data unit of an attribute. An attribute data unit is generated for each attribute included in an attribute.

[0038] A slice consists of one geometry data unit and zero or more attribute data units. A slice consists of a single or multiple consecutive data units in a G-PCC bitstream. Each data unit stores slice identification information (slice_id) that indicates the slice to which the data unit belongs. In other words, data units that belong to the same slice store the same slice identification information. In this way, geometry data units and attribute data units that belong to the same slice are linked together using the slice identification information.

[0039] A tile consists of one or more consecutive slices in a G-PCC bitstream. Slices and tiles are associated with each other using a slice_tag stored in a geometry data unit. The slice_tag is identification information that indicates the tile to which the slice belongs.

[0040] In the tile inventory, information such as the position and size of a tile in three-dimensional space corresponding to each tile identification information is linked. In other words, when a desired point in three-dimensional space is to be played back, the necessary data unit can be identified and extracted based on the tile identification information (and also slice identification information). Therefore, partial access can be realized, and unnecessary information does not need to be decoded, thereby suppressing an increase in the load of the playback process.

[0041] <1-6.ISOBMFF> Non-Patent Document 2 discloses the International Organization for Standardization Base Media File Format (ISOBMFF), which is a file container specification of the international standard technology for video compression, MPEG-4 (Moving Picture Experts Group-4).

[0042] <1-7.Storing G-PCC bitstream in ISOBMFF> Non-Patent Document 3 discloses a method for storing a G-PCC bitstream in ISOBMFF, with the aim of improving the efficiency of playback processing from local storage and network distribution of bitstreams coded with G-PCC. This method is currently being standardized in MPEG-I Part 18 (ISO / IEC 23090-18).

[0043] 5 is a diagram showing an example of a file structure in this case. A G-PCC bitstream stored in an ISOBMFF is called a G-PCC file.

[0044] The sequence parameter set is stored in the GPCCDecoderConfigurationRecord of the G-PCC file. The GPCCDecoderConfigurationRecord may further store a geometry parameter set, an attribute parameter set, and a tile inventory depending on the sample entry type.

[0045] A sample in a media data box (Media) can store geometry and attributes corresponding to one point cloud frame, and depending on the sample entry type, the sample can store a geometry parameter set, an attribute parameter set, and a tile inventory.

[0046] <1-8. Partial access structure of G-PCC file> This G-PCC file has a structure for decoding by partial access based on 3D spatial information. Partial access means accessing (extracting data from) a partial point cloud, which is a part of the object represented by the point cloud (i.e., a part of the point cloud data). In particular, in distribution use cases, using this type of partial access makes it possible to distribute data for each track that stores the partial point cloud (i.e., realize adaptive distribution), which is useful for suppressing increases in processing load and bandwidth load.

[0047] For example, a G-PCC file can have multiple independently accessible tracks, as shown in Fig. 6. The G-PCC tile track shown in Fig. 6 is a track that stores a partial point cloud and stores data for one or more tiles. The G-PCC tile base track stores information such as a parameter set and tile inventory that are common to the G-PCC tile tracks associated with that track. The G-PCC tile base track and the G-PCC tile track are associated with each other by a track reference (tref).

[0048] Figure 6 shows an example of a configuration in which geometry and attributes are stored in one G-PCC tile track. As shown in Figure 7, geometry and attributes may be stored in different G-PCC tile tracks. In this case, the G-PCC geometry tile track that stores geometry and the G-PCC attribute tile track that stores attributes are linked by a track reference (tref).

[0049] In this G-PCC file, a 3D spatial region can be defined as a partial point cloud. As shown in Figure 8, a 3D spatial region is defined by the position of the reference point (anchor) (the 3D coordinates of the reference point (anchor_x, anchor_y, anchor_z)) and the size (region_dx, region_dy, region_dz). Information about such a 3D spatial region (3D spatial information) is managed in the GPCC Spatial Region InfoBox (GPCCSpatialRegionInfoBox) stored in the sample entry of the G-PCC tile base track.

[0050] An example of the syntax of GPCCSpatialRegionInfoBox is shown in Fig. 9. As shown in the fourth to eleventh lines from the top of Fig. 9, information about each 3D spatial region is set in the GPCCSpatialRegionInfoBox. For example, as shown in the fifth line from the top of Fig. 9, a 3DSpatialRegionStruct that defines each 3D spatial region is specified in the GPCCSpatialRegionInfoBox. An example of the syntax of this 3DSpatialRegionStruct is shown in Fig. 10. As shown in Fig. 10, the position (anchor_x, anchor_y, anchor_z) and size (region_dx, region_dy, region_dz) of the reference point of the 3D spatial region are set in this 3DSpatialRegionStruct.

[0051] This 3D spatial region is composed of one or more tiles. As shown in lines 6 to 10 of Fig. 9, in the GPCCSpatialRegionInfoBox, tiles that make up each 3D spatial region are specified using tile identification information (tile_id).

[0052] That is, in a G-PCC file, a 3D spatial region and tiles that make up the 3D spatial region are managed.

[0053] Furthermore, in a G-PCC tile track, the tiles stored therein are managed in a GPCC tile sample entry (GPCCTileSampleEntry). An example of the syntax of the GPCCTileSampleEntry is shown in Figure 11. As shown in lines 7 to 9 from the top of Figure 11, in the GPCCTileSampleEntry, the tiles stored in the G-PCC tile track are specified using tile identification information (tile_id).

[0054] In other words, a 3D spatial region and a track that stores that data are linked via a tile. Therefore, partial access is performed, for example, as follows:

[0055] 1. The decoder identifies the G-PCC tile base track and the G-PCC tile track in the G-PCC file. 2. The decoder parses the sample entry of the G-PCC tile-based track and obtains the tile_id of the tiles that make up the desired 3D spatial region from the GPCCSpatialRegionInfoBox. 3. The decoder parses the sample entries of all G-PCC tile tracks and identifies the G-PCC tile track in which the tile with the desired tile_id is stored. 4. Extract and decode the data of the desired tile from the identified G-PCC tile track.

[0056] The position, size, shape, orientation, number, etc. of objects represented by a point cloud can change over time (can be dynamic). Therefore, the 3D spatial region and the tiles that make up the 3D spatial region can also change over time (can be dynamic). Furthermore, the tiles stored in a track can also change over time (can be dynamic). In this specification, the term "dynamic" refers to an object, such as information, a state, or a relationship, that changes over time, and the term "static" refers to an object, such as information, a state, or a relationship, that does not change over time.

[0057] The static 3D spatial information of the partial point cloud is stored in the GPCCSpatialRegionInfoBox described above. The dynamic 3D spatial information is stored in a dynamic spatial region timed metadata track linked to the G-PCC tile base track using a track reference (tref), as shown in Fig. 12. If the tiles stored in the G-PCC tile track change in the time direction, the tile identification information (tile_id) that changes in the time direction is stored in a subsample information box.

[0058] <2. Information transmission based on temporal changes in relationships in a 3D spatial region> <2-1. Building a point cloud> However, when the 3D spatial region, the tiles that make up the 3D spatial region, the tiles stored in each G-PCC tile track, etc. are managed as dynamic information in this manner, these may change from frame to frame.

[0059] For example, consider content that provides a user with a two-dimensional image of a three-dimensional space region containing an object represented by a point cloud, as seen from a viewpoint. In this specification, the range of the three-dimensional space region visible from a certain viewpoint (visible when looking in a certain direction from a certain position) is referred to as the field of view (or field of view area).

[0060] For example, in cases where the position and direction of the viewpoint can be changed, such as in so-called 6DoF content, or when the point cloud is configured as dynamic data (i.e., when objects may change over time), objects within the field of view may deform, expand, contract, move, appear, or disappear. In other words, information such as the 3D spatial region to be played back, the tiles that make up that 3D spatial region, and the tiles stored in the G-PCC tile track may change over time. Therefore, in such cases, the method described in Non-Patent Document 3 manages this information as dynamic information in the G-PCC file.

[0061] In the case of the method described in Non-Patent Document 3, if this information is managed as dynamic information, it can change arbitrarily for each frame. Therefore, it is necessary to check this information for each frame. In other words, it is necessary to parse all tracks for each frame.

[0062] However, even with 6DoF content or dynamic point clouds, such degrees of freedom may not be necessary. For example, if the viewpoint position and direction do not change and the object positions do not change significantly, the objects in the field of view may not increase, decrease, or be replaced from frame to frame, resulting in a static 3D spatial region. Furthermore, the tiles that make up the 3D spatial region and the tiles stored in the G-PCC tile track may not change from frame to frame.

[0063] In such a case, the method described in Non-Patent Document 3 may unnecessarily increase the load of the reproduction process.

[0064] <2-2. Transmission of the first information and the second information> Therefore, as shown in the top row of the table in Figure 13, first information regarding changes in the relationship between 3D spatial regions over time and second information regarding the 3D spatial region generated based on the first information are transmitted (Method 1).

[0065] For example, an information processing device may include a first information generation unit that generates first information regarding changes in relationships between independently decodable three-dimensional spatial regions of a point cloud that represents a three-dimensional object, a second information generation unit that generates second information regarding the three-dimensional spatial region according to the first information, and a file generation unit that generates a file that stores a bit stream of encoded data into which the point cloud is encoded, the first information, and the second information.

[0066] For example, in an information processing method, first information regarding changes in relationships for an independently decodable three-dimensional spatial region of a point cloud representing a three-dimensional object is generated, second information regarding the three-dimensional spatial region is generated according to the first information, and a file is generated that stores a bit stream of encoded data in which the point cloud is encoded, the first information, and the second information.

[0067] This allows the playback device to extract data on tiles that make up the 3D spatial region for constructing a point cloud from the bitstream based on the first information and the second information. This allows playback without checking information such as the 3D spatial region to be played back, the tiles that make up that 3D spatial region, and the tiles stored in the G-PCC tile track for each frame. This prevents an increase in the playback processing load.

[0068] For example, an information processing device may include an extraction unit that references first information regarding changes in the relationship between an independently decodable three-dimensional spatial region of a point cloud stored in a file that stores a bit stream of encoded data in which a point cloud representing a three-dimensional object is encoded, and, if the relationship is static, extracts data of tiles that constitute the three-dimensional spatial region that constructs the point cloud based on second information regarding the three-dimensional spatial region generated in accordance with the first information, and a decoding unit that decodes the extracted data.

[0069] For example, in an information processing method, first information regarding changes in the relationship between an independently decodable three-dimensional spatial region of a point cloud that represents a three-dimensional object is referenced, and the first information is stored in a file that stores a bit stream of encoded data.If the relationship is static, data of tiles that constitute the three-dimensional spatial region that constructs the point cloud is extracted based on second information regarding the three-dimensional spatial region generated in accordance with the first information, and the extracted data is decoded.

[0070] This allows playback without checking information such as the 3D spatial region to be played back, the tiles that make up the 3D spatial region, and the tiles stored in the G-PCC tile track for each frame, thereby suppressing an increase in the playback processing load.

[0071] <2-3. Relationships including spatial positional relationships between 3D spatial regions> When applying Method 1, the first information may be information indicating whether the relationship, including the spatial positional relationship, between 3D spatial regions is static, as shown in the second row from the top of the table in Fig. 13. Furthermore, the second information may be information (3DBoundingSpaceStruct) indicating the possible existence range of the 3D spatial region, which is generated when the first information is true (Method 1-1).

[0072] For example, a first information generation unit of an information processing device may generate, as first information, information indicating whether a relationship, including a positional relationship in three-dimensional space, between three-dimensional spatial regions is static, and a second information generation unit of the information processing device may generate, as second information, information indicating a range in which the three-dimensional spatial region may exist, if the first information is true.

[0073] The first information stored in the G-PCC file may be information indicating whether the relationship between 3D spatial regions, including their positional relationship in 3D space (also referred to as spatial positional relationship), is static. The second information stored in the G-PCC file may be static information indicating a range in which the 3D spatial region can exist. An extraction unit of the information processing device may then identify the 3D spatial region in which the point cloud is to be constructed, based on the static information indicating the range in which the 3D spatial region can exist.

[0074] In other words, in the case of method 1-1, the relationship between 3D spatial regions includes the spatial positional relationship between the 3D spatial regions. Then, flag information indicating whether the relationship is static or not is generated as first information and stored in the G-PCC file. This makes it easy to determine whether the spatial positional relationship between the 3D spatial regions is static or not based on the first information.

[0075] Furthermore, when the first information (flag information) is true, that is, when the relationship between 3D spatial regions, including their positional relationships in three-dimensional space, is static, a 3D bounding space is set, which is a range within which each 3D spatial region can exist. For example, as shown in Fig. 14, a 3D bounding space (3D bounding space 51 to 3D bounding space 54) is set for each 3D spatial region in three-dimensional space.

[0076] This 3D bounding space is a static range whose position and size do not change over time. Furthermore, 3D bounding spaces are set so that they do not overlap with each other. A dynamic 3D spatial region is always completely contained within the 3D bounding space corresponding to that 3D spatial region, regardless of time.

[0077] 15, at both times t=t1 and t=t2, 3D spatial region 61 exists (is completely contained) within 3D bounding space 51 set for 3D spatial region 61. Similarly, 3D spatial region 62 exists (is completely contained) within 3D bounding space 52, 3D spatial region 63 exists within 3D bounding space 53, and 3D spatial region 64 exists within 3D bounding space 54. In other words, the spatial positional relationship between the 3D spatial regions is guaranteed (is a static relationship) by this 3D bounding space.

[0078] A 3D bounding space struct (3DBoundingSpaceStruct) that defines this 3D bounding space is generated as second information and stored in the G-PCC file. This makes it easy to understand the static spatial relationship between 3D spatial regions based on the second information.

[0079] That is, the playback device can easily determine whether the relationships among 3D spatial regions, including the spatial positional relationships between 3D spatial regions, are static or not, and the spatial positional relationships between those 3D spatial regions, based on the first information and the second information. Therefore, the playback device can play back the 3D spatial region to be played back without checking information about the 3D spatial region to be played back, the tiles that make up that 3D spatial region, the tiles stored in the G-PCC tile track, and so on, for each frame. This can suppress an increase in the load of the playback process.

[0080] <2-4.static_region_relation> When applying method 1-1, as shown in the third row from the top of the table in FIG. 13, the first information may be information (static_region_relation flag) indicating whether the spatial positional relationship between 3D spatial regions is static (method 1-1-1). The static_region_relation flag is information indicating whether the spatial positional relationship between 3D spatial regions is static. For example, a value of "0" indicates that the spatial positional relationship between 3D spatial regions is dynamic, and a value of "1" indicates that the spatial positional relationship between 3D spatial regions is static. In this case, the second information (3DBoundingSpaceStruct) is generated when the value of the static_region_relation flag is "1."

[0081] That is, the SampleEntry of the dynamic spatial region timed metadata track may be extended to store a static_region_relation flag indicating that the spatial positional relationship of the 3D spatial region is static as the first information, and a 3DBoundingSpaceStruct as the second information.

[0082] For example, a first information generating unit of an information processing device may generate, as the first information, information (static_region_relation flag) indicating whether the positional relationship in three-dimensional space between three-dimensional spatial regions is static.

[0083] Furthermore, the first information stored in the G-PCC file may be information (static_region_relation flag) indicating whether the positional relationship between 3D spatial regions in a 3D space is static.

[0084] <2-4-1. Syntax example 1> In this case, for example, the first information and the second information may be stored in the dynamic spatial region timed metadata track of the G-PCC file. An example of the syntax of the dynamic spatial region timed metadata track is described below. Note that, here, as in the example described with reference to Figures 9 and 11, the 3D spatial region and the track storing that data are linked via the tile (via tile_id).

[0085] FIG. 16 is a diagram showing an example of the syntax of a dynamic GPCC3D spatial region sample entry (DynamicGPCC3DSpatialRegionSampleEntry) stored in the sample entry of the dynamic spatial region timed metadata track.

[0086] As shown in the fifth line from the top of the syntax shown in Fig. 16, a static_region_relation flag (first information) is stored in this DynamicGPCC3DSpatialRegionSampleEntry. Also, as shown in the seventh and eighth lines from the top of the syntax shown in Fig. 16, if the value of the static_region_relation flag is "1", a 3DBoundingSpaceStruct (second information) is stored in DynamicGPCC3DSpatialRegionSampleEntry.

[0087] FIG. 17 is a diagram showing an example of the syntax of a dynamic GPCC3D spatial region sample (DynamicGPCC3DSpatialRegionSample) stored in the dynamic spatial region timed metadata track.

[0088] As shown in the third to eighth lines from the top of the syntax shown in Figure 17, in this DynamicGPCC3DSpatialRegionSample, for each 3D spatial region of the sample, a 3DSpatialRegionStruct that defines the position (anchor_x, anchor_y, anchor_z) and size (region_dx, region_dy, region_dz) of the reference point of the 3D spatial region, and the tiles that make up the 3D spatial region (tile identification information (tile_id)) are specified.

[0089] FIG. 18 is a diagram illustrating an example of the syntax of a 3D bounding space struct (3DBoundingSpaceStruct) stored in the dynamic spatial region timed metadata track.

[0090] As shown in the fourth and fifth lines from the top of the syntax shown in Fig. 18, in this 3DBoundingSpaceStruct, a 3DSpatialRegionStruct that defines each 3D bounding space is specified. In other words, each entry of this NumRegions loop specifies the 3DSpatialRegionStruct of the 3D bounding space corresponding to the 3DSpatialRegionStruct of the entry with the same index in the num_regions loop of the GPCCSpatialRegionInfoBox of the same sample entry.

[0091] As with the 3D spatial region, this 3DSpatialRegionStruct defines the position and size of the reference point of the 3D bounding space. As described above, the 3D bounding space is a static region, and its position and size do not change over time. Therefore, the 3DSpatialRegionStruct that defines each 3D bounding space is static information.

[0092] Note that 3DSpatialRegionStruct and 3DSpatialRegionStruct may be linked together using the 3d_region_id stored in the 3DSpatialRegionStruct.

[0093] That is, in this case, the static_region_relation flag (first information) is stored in DynamicGPCC3DSpatialRegionSampleEntry, as described with reference to Fig. 16. Furthermore, if the value of the static_region_relation flag is "1", the 3DBoundingSpaceStruct (second information) as described with reference to Fig. 18 is stored in DynamicGPCC3DSpatialRegionSampleEntry.

[0094] Therefore, based on this information, the playback device can easily determine whether the spatial positional relationship between 3D spatial regions is static and can easily grasp the spatial positional relationship between those 3D spatial regions. Therefore, the playback device can play back the 3D spatial region to be played back without checking information such as the tiles that make up the 3D spatial region and the tiles stored in the G-PCC tile track for each frame. This can prevent an increase in the playback processing load.

[0095] For example, if the value of the static_region_relation flag is "1," the playback device can determine that the spatial relationship between 3D spatial regions is static based on the value of the flag. Furthermore, the playback device can determine the spatial relationship based on the 3DBoundingSpaceStrcut. Therefore, for example, after the playback device acquires G-PCC tile tracks (G-PCC tile track(s)) corresponding to a desired 3D spatial region according to the field of view, it is not necessary to identify the G-PCC tile tracks (G-PCC tile track(s)) included in the field of view and switch to those G-PCC tile tracks as long as the field of view is not changed.

[0096] <2-4-2. Syntax example 2> In <2-4-1. Syntax Example 1>, it has been described that the 3D spatial region and the track storing that data are linked via a tile (via tile_id), but instead of this tile_id, they may be linked using tile track identification information (tile_track_id) that identifies the G-PCC tile track. An example of the syntax of the dynamic spatial region timed metadata track in this case is described below.

[0097] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to Fig. 16. Also, the syntax of 3DBoundingSpaceStruct is the same as the example described with reference to Fig. 18.

[0098] FIG. 19 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample in this case.

[0099] 19, in this case, a loop is performed using the number of G-PCC tile tracks (num_tile_tracks) corresponding to each 3D spatial region of the sample, and tile track identification information (tile_track_id) is specified as shown on line 7. In other words, the tile track identification information (tile_track_id) of the G-PCC tile track corresponding to each 3D spatial region of the sample is specified.

[0100] By doing this, the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks.

[0101] <2-5.static_mapping> In <2-4.static_region_relation>, we have described a case where the first information is information indicating whether the spatial positional relationship between 3D spatial regions is static (static_region_relation flag), but the first information is not limited to this example.

[0102] For example, when applying method 1-1, as shown in the fourth row from the top of the table in FIG. 13, the first information may be information (static_mapping flag) indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles are static (method 1-1-2). The static_mapping flag is information indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles are static. For example, a value of “0” indicates that the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles are dynamic, and a value of “1” indicates that the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles are static. In this case, the second information (3DBoundingSpaceStruct) is generated when the value of the static_mapping flag is “1.”

[0103] In other words, the SampleEntry of the dynamic spatial region timed metadata track may be extended to store, as the first information, a static_mapping flag indicating that the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial region and the information for obtaining the tile are static, and a 3DBoundingSpaceStruct may be stored as the second information.

[0104] For example, a first information generation unit of an information processing device may generate, as the first information, information (static_mapping flag) indicating whether the positional relationship in three-dimensional space between three-dimensional spatial regions and the correspondence between the three-dimensional spatial region and information for obtaining tiles of a point cloud are static.

[0105] Furthermore, the first information stored in the G-PCC file may be information (static_mapping flag) indicating the positional relationship in three-dimensional space between three-dimensional spatial regions and whether the correspondence between the three-dimensional spatial regions and the information for obtaining the tiles is static.

[0106] <2-5-1. Syntax example 1> An example of the syntax of the dynamic spatial region timed metadata track in this case is explained below. Note that, as in the example of <2-4-1. Syntax Example 1>, the 3D spatial region and the track that stores that data are linked via the tile (tile_id).

[0107] FIG. 20 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSampleEntry stored in the sample entry of the dynamic spatial region timed metadata track.

[0108] As shown in the fifth line from the top of the syntax shown in Fig. 20, a static_mapping flag (first information) is stored in this DynamicGPCC3DSpatialRegionSampleEntry. Also, as shown in the seventh and eighth lines from the top of the syntax shown in Fig. 20, if the value of the static_mapping flag is "1", a 3DBoundingSpaceStruct (second information) is stored in DynamicGPCC3DSpatialRegionSampleEntry.

[0109] In this case, the syntax of DynamicGPCC3DSpatialRegionSample is the same as the example described with reference to Fig. 17. Also, the syntax of 3DBoundingSpaceStruct is the same as the example described with reference to Fig. 18.

[0110] That is, in this case, the static_mapping flag (first information) is stored in DynamicGPCC3DSpatialRegionSampleEntry, as described with reference to Fig. 20. Furthermore, if the value of the static_mapping flag is "1", the 3DBoundingSpaceStruct (second information) as described with reference to Fig. 18 is stored in DynamicGPCC3DSpatialRegionSampleEntry.

[0111] Therefore, based on this information, the playback device can easily grasp the spatial positional relationship between 3D spatial regions, whether the correspondence between the 3D spatial region and the information for obtaining the tiles is static, and the spatial positional relationship between the 3D spatial regions. Therefore, the playback device can play back the 3D spatial region to be played back, the tiles that make up the 3D spatial region, the tiles stored in the G-PCC tile track, and other information without checking each frame. This can suppress an increase in the load of the playback process.

[0112] For example, if the value of the static_mapping flag is "1," the playback device can determine, based on the value of the flag, that the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles are static. Furthermore, the playback device can determine the spatial positional relationship based on the 3DBoundingSpaceStrcut. Therefore, for example, after the playback device acquires G-PCC tile track(s) corresponding to a desired 3D spatial region according to the field of view, it is not necessary to identify the G-PCC tile track(s) included in the field of view and switch to the G-PCC tile track(s) as long as the field of view is not changed.

[0113] <2-5-2. Syntax example 2> In <2-5-1. Syntax Example 1>, it has been described that the 3D spatial region and the track that stores that data are linked via a tile (via tile_id), but they may also be linked using tile track identification information (tile_track_id) instead of this tile_id.

[0114] An example of the syntax for the dynamic spatial region timed metadata track in this case is described below.

[0115] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to Fig. 20. Also, the syntax of DynamicGPCC3DSpatialRegionSample is the same as the example described with reference to Fig. 19. That is, the tile track identification information (tile_track_id) of the G-PCC tile track corresponding to each 3D spatial region of the sample is specified. Also, the syntax of 3DBoundingSpaceStruct is the same as the example described with reference to Fig. 18.

[0116] By doing this, the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks.

[0117] <2-6.DynamicGPCC3DSpatialRegionSample> Furthermore, as shown in the fifth row from the top of the table in FIG. 13, the second information may further include information (DynamicGPCC3DSpatialRegionSample) about the 3D spatial region that includes a static correspondence between the 3D spatial region and information for obtaining tiles of the point cloud (Method 1-1-3).

[0118] When this method 1-1-3 is applied, the first information may be information indicating whether the spatial positional relationship between 3D spatial regions is static (static_region_relation flag), or information indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial region and information for obtaining a tile are static (static_mapping flag). Furthermore, the information for obtaining a tile may be tile identification information (tile_id) or tile track identification information (tile_track_id).

[0119] For example, the second information generation unit of the information processing device may further generate, as the second information, information about a static 3D spatial region, including a correspondence between the 3D spatial region and information for obtaining tiles of a point cloud.

[0120] In this case, the information for obtaining the tile may be the tile's identification information (tile_id), or may be the identification information (tile_track_id) of the track (G-PCC tile track) that stores the tile data in the G-PCC file.

[0121] The second information stored in the G-PCC file may further include information about the 3D spatial region, including a correspondence between the 3D spatial region and information for obtaining tiles. An extraction unit of the information processing device may then extract, from the file, data on tiles that constitute the 3D spatial region identified based on the static information indicating a range in which the 3D spatial region may exist, based on the information about the 3D spatial region.

[0122] In this case, the information for obtaining the tile may be the tile's identification information (tile_id), or may be the identification information (tile_track_id) of the track (G-PCC tile track) that stores the tile data in the G-PCC file.

[0123] That is, Method 1-1-3 can be applied to both Syntax Example 1 and Syntax Example 2 of Method 1-1-1 and Syntax Example 1 and Syntax Example 2 of Method 1-1-2.

[0124] For example, when applying Method 1-1-3 to Syntax Example 1 of Method 1-1-1, in the DynamicGPCC3DSpatialRegionSample whose syntax is shown in Figure 17, when static_region_relation = 1, everything except 3DSpatialRegionStruct should be the same as the value stored in the GPCCSpatialRegionInfoBox of the sample entry.

[0125] Furthermore, when applying Method 1-1-3 to Syntax Example 2 of Method 1-1-1, in the DynamicGPCC3DSpatialRegionSample whose syntax is shown in Figure 19, when static_region_relation = 1, all values ​​except for 3DSpatialRegionStruct shall be the same as the values ​​stored in the GPCCSpatialRegionInfoBox of the sample entry.

[0126] Furthermore, when applying Method 1-1-3 to Syntax Example 1 of Method 1-1-2, in the DynamicGPCC3DSpatialRegionSample whose syntax is shown in Figure 17, when static_mapping = 1, all values ​​except for 3DSpatialRegionStruct shall be the same as the values ​​stored in the GPCCSpatialRegionInfoBox of the sample entry.

[0127] Furthermore, when applying Method 1-1-3 to Syntax Example 2 of Method 1-1-2, in the DynamicGPCC3DSpatialRegionSample whose syntax is shown in Figure 19, when static_mapping = 1, all values ​​except for 3DSpatialRegionStruct shall be the same as the values ​​stored in the GPCCSpatialRegionInfoBox of the sample entry.

[0128] By doing so, the correspondence between the 3D spatial region stored in DynamicGPCC3DSpatialRegionSample and the information for obtaining the tile (tile_id or tile_track_id) becomes the same as the static correspondence between the 3D spatial region stored in GPCCSpatialRegionInfoBox and the information for obtaining the tile (tile_id or tile_track_id). Therefore, the playback device does not need to identify, for each frame, the G-PCC tile track that stores the data of the tiles that make up the 3D spatial region to be played back, and can easily extract and play back the data of the tiles that make up the 3D spatial region. This can suppress an increase in the load of the playback process.

[0129] <2-7. Fixing the reference point coordinates of 3DSpatialRegionStruct> Instead of setting a 3D bounding space and transmitting a 3DBoundingSpaceStruct as the second information as in method 1-1, the position of the anchor point of the 3D spatial region may be fixed (i.e., static) in the time direction.

[0130] That is, when applying Method 1, the first information may be information indicating whether the relationship, including the spatial positional relationship, between 3D spatial regions is static, as shown in the sixth row from the top of the table in Fig. 13. Furthermore, the second information may be information (3DSpatialRegionStruct) indicating a 3D spatial region whose reference point position is fixed when the first information is true (Method 1-2).

[0131] For example, a first information generation unit of the information processing device may generate, as first information, information indicating whether a relationship, including a positional relationship in three-dimensional space, between three-dimensional spatial regions is static, and a second information generation unit of the information processing device may generate, if the first information is true, information indicating a three-dimensional spatial region in which the reference point position of the 3D spatial region is static, as second information.

[0132] The first information stored in the G-PCC file may be information indicating whether the relationship between 3D spatial regions, including their positional relationship in 3D space (also referred to as spatial positional relationship), is static. The second information stored in the G-PCC file may be information indicating a 3D spatial region whose reference point position is static. Then, an extraction unit of the information processing device may identify the 3D spatial region in which a point cloud is to be constructed, based on the information indicating the 3D spatial region.

[0133] The first information may be, for example, a static_region_relation flag or a static_mapping flag. When the first information is true in the 3DSpatialRegionStruct (for example, when static_region_relation = 1 or static_mapping = 1), a constraint may be added that the position of the reference point of the 3D spatial region (coordinates of the reference point (anchor_x, anchor_y, anchor_z)) is fixed (static) in the time direction, and only the size can change (dynamic) in the time direction, as shown in FIG. 21 . In the example of FIG. 21 , the sizes of the 3D spatial regions 61 to 64 are dynamic (the sizes are different from each other at time t=t1 and time t=t2), but the positions of the reference points (reference points 71 to 74) of the 3D spatial regions 61 to 64 are static (the positions are the same from each other at time t=t1 and time t=t2). Then, the 3DSpatialRegionStruct with such constraints added may be transmitted as the second information.

[0134] Fig. 22 is a diagram showing an example of the syntax of 3DSpatialRegionStruct in this case. As shown in Fig. 22, the coordinates of the reference point (anchor_x, anchor_y, anchor_z) are included in the if statement, and if the first information is true (for example, static_region_relation = 1 or static_mapping = 1) and the reference point position is static, the setting of the coordinates of the reference point in this sample can be omitted.

[0135] By statically setting the reference point position of each 3D spatial region, the spatial relationship between the 3D spatial regions is guaranteed (the relationship becomes static). In other words, the static spatial relationship between the 3D spatial regions can be easily determined based on the second information (3DSpatialRegionStruct) stored in the G-PCC file. Therefore, as in method 1-1, the playback device can play back the 3D spatial region to be played back, the tiles that make up the 3D spatial region, the tiles stored in the G-PCC tile track, and other information without checking each frame. This can suppress an increase in the load of the playback process.

[0136] <2-8. Fixing the center coordinate of 3DSpatialRegionStruct> Instead of the reference point position of the 3D spatial region, the position of the center point of the 3D spatial region may be fixed (i.e., made static) in the time direction.

[0137] That is, when applying Method 1, the first information may be information indicating whether the relationship, including the spatial positional relationship, between 3D spatial regions is static, as shown in the seventh row from the top of the table in Fig. 13. Furthermore, the second information may be information (3DSpatialRegionStruct) indicating a 3D spatial region whose center position is fixed when the first information is true (Method 1-3).

[0138] For example, a first information generation unit of the information processing device may generate, as first information, information indicating whether a relationship, including a positional relationship in three-dimensional space, between three-dimensional spatial regions is static, and a second information generation unit of the information processing device may generate, if the first information is true, information indicating a three-dimensional spatial region whose center position is static, as second information.

[0139] The first information stored in the G-PCC file may be information indicating whether the relationship between 3D spatial regions, including their positional relationship in 3D space (also referred to as spatial positional relationship), is static. The second information stored in the G-PCC file may be information indicating a 3D spatial region whose center position is static. Then, an extraction unit of the information processing device may identify the 3D spatial region in which a point cloud is to be constructed, based on the information indicating the 3D spatial region.

[0140] The first information may be, for example, a static_region_relation flag or a static_mapping flag. When the first information is true in the 3DSpatialRegionStruct (for example, when static_region_relation = 1 or static_mapping = 1), a constraint may be added that the position of the center of the 3D spatial region (center coordinates (center_x, center_y, center_z)) is fixed (static) in the time direction, and only the size can change (dynamic) in the time direction, as shown in FIG. 23 . In the example of FIG. 23 , the sizes of the 3D spatial regions 61 to 64 are dynamic (the sizes are different from each other at time t=t1 and time t=t2), but the positions of the center points (center points 81 to 84) of the 3D spatial regions 61 to 64 are static (the positions are the same from each other at time t=t1 and time t=t2). Then, the 3DSpatialRegionStruct with such constraints added may be transmitted as the second information.

[0141] As described with reference to FIG. 12, the center coordinates (center_x, center_y, center_z) of the 3D spatial region are not set in the 3DSpatialRegionStruct. These coordinates can be derived, for example, using the following equation. That is, if the first information is true, the coordinates of the reference point and the size of the 3D spatial region are set using the following equation so that the center coordinates (center_x, center_y, center_z) of the 3D spatial region are static.

[0142] center_x = anchor_x+region_dx / 2 center_y = anchor_y+region_dy / 2 center_z = anchor_z+region_dz / 2

[0143] In addition, the center coordinates (center_x, center_y, center_z) of the 3D spatial region may be newly signaled in the sample entry of the dynamic spatial region timed metadata track, and if the first information is true, only the size of the 3D spatial region (region_dx, region_dy, region_dz) may be set for each sample by the 3DSpatialRegionStruct. By statically setting the center position of each 3D spatial region, the spatial relationship between the 3D spatial regions is guaranteed (a static relationship is established). In other words, the static spatial relationship between the 3D spatial regions can be easily determined based on the second information (3DSpatialRegionStruct) stored in the G-PCC file. Therefore, as in method 1-1, the playback device can play back the 3D spatial region to be played back without checking information such as the tiles that make up the 3D spatial region and the tiles stored in the G-PCC tile track for each frame. This can suppress an increase in the load of the playback process.

[0144] <2-9. Relationships including correspondences between 3D spatial regions and information for obtaining tiles> If the correspondence between the 3D spatial region and the information for obtaining tiles is static, there will be fields whose values ​​do not change in the samples of the dynamic spatial region timed metadata. Therefore, if the correspondence between the 3D spatial region and the information for obtaining tiles is static, you may omit specifying the information for obtaining tiles that make up the 3D spatial region in DynamicGPCC3DSpatialRegionSample.

[0145] That is, when applying method 1, the first information may be information indicating whether the relationship, including the correspondence between the 3D spatial region and the information for obtaining tiles, is static, as shown in the eighth row from the top of the table in Fig. 13. Furthermore, the second information may be dynamic information (DynamicGPCC3DSpatialRegionSample) regarding a three-dimensional spatial region in which the correspondence between the 3D spatial region and the information for obtaining tiles is omitted when the first information is true (method 1-4).

[0146] For example, a first information generation unit of an information processing device may generate, as first information, information indicating whether a relationship, including a correspondence between a 3D spatial region and information for obtaining tiles of a point cloud, is static, and if the first information is true, a second information generation unit of the information processing device may generate, as second information, information regarding a dynamic 3D spatial region (DynamicGPCC3DSpatialRegionSample) without including information indicating the correspondence.

[0147] In this case, the information for obtaining the tile may be the tile's identification information (tile_id) or the identification information (tile_track_id) of the track that stores the tile data in the G-PCC file.

[0148] The first information stored in the G-PCC file may be information indicating whether the relationship, including the correspondence between a 3D spatial region and information for obtaining point cloud tiles, is static. The second information stored in the G-PCC file may be information about a dynamic 3D spatial region (DynamicGPCC3DSpatialRegionSample) that does not include information indicating the correspondence. An extraction unit of the information processing device may then identify the 3D spatial region in which to construct the point cloud based on the information about the dynamic 3D spatial region and the information indicating the static correspondence between the 3D spatial region and information for obtaining point cloud tiles.

[0149] In this case, the information for obtaining the tile may be the tile's identification information (tile_id) or the identification information (tile_track_id) of the track that stores the tile data in the G-PCC file.

[0150] This makes it possible to suppress an increase in the amount of information in the dynamic spatial region timed metadata, and thus to suppress an increase in the amount of information in the G-PCC file. Therefore, it is possible to suppress an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, it becomes easier to parse the dynamic spatial region timed metadata, and it is possible to suppress an increase in the load of the playback process.

[0151] <2-10.static_tile_mapping> When applying Method 1-4, as shown in the ninth row from the top of the table in FIG. 13, the first information may be information (static_tile_mapping flag) indicating whether the correspondence between the 3D spatial region and the information for obtaining tiles is static (Method 1-4-1). The static_tile_mapping flag is information indicating whether the correspondence between the 3D spatial region and the information for obtaining tiles is static. For example, a value of "0" indicates that the correspondence is dynamic, and a value of "1" indicates that the correspondence is static. If the value of this static_tile_mapping flag is "1," the second information (DynamicGPCC3DSpatialRegionSample) may not include (store) information indicating the correspondence between the 3D spatial region and the information for obtaining tiles.

[0152] For example, a first information generation unit of an information processing device may generate, as the first information, information (static_tile_mapping flag) indicating whether the correspondence between a 3D spatial region and information for obtaining tiles of a point cloud is static.

[0153] In addition, the first information stored in the G-PCC file may be information (static_tile_mapping flag) indicating whether the correspondence between the 3D spatial region and the information for obtaining tiles of the point cloud is static.

[0154] <2-10-1. Syntax example 1> In this case, for example, the first information and the second information may be stored in the dynamic spatial region timed metadata track of the G-PCC file. An example of the syntax of the dynamic spatial region timed metadata track is described below. Note that, here, it is assumed that the information for obtaining a tile is tile identification information (tile_id).

[0155] FIG. 24 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSampleEntry stored in the sample entry of the dynamic spatial region timed metadata track.

[0156] As shown in the fifth line from the top of the syntax shown in FIG. 24, this DynamicGPCC3DSpatialRegionSampleEntry stores a static_tile_mapping flag (first information).

[0157] FIG. 25 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample stored in the dynamic spatial region timed metadata track.

[0158] As shown in the fifth to ninth lines from the top of the syntax shown in FIG. 25 , in this DynamicGPCC3DSpatialRegionSample, if the value of the static_tile_mapping flag is “0 (false),” identification information (tile_id) of the tile corresponding to the 3D spatial region (i.e., the tiles constituting the 3D spatial region) is specified for each 3D spatial region included in the sample. That is, in this case, the DynamicGPCC3DSpatialRegionSample includes a list of tile identification information (tile_id) corresponding to each 3D spatial region of the sample. In contrast, if the value of the static_tile_mapping flag is “1 (true),” the specification of the tile identification information (tile_id) is omitted. That is, if the value of the static_tile_mapping flag is “1 (true),” the DynamicGPCC3DSpatialRegionSample does not include a list of tile identification information (tile_id) corresponding to each 3D spatial region of the sample.

[0159] This makes it possible to prevent unnecessary information from being stored in the dynamic spatial region timed metadata. Therefore, it is possible to prevent an increase in the amount of information in the dynamic spatial region timed metadata, and therefore an increase in the amount of information in the G-PCC file. Therefore, it is possible to prevent an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, it becomes easier to parse the dynamic spatial region timed metadata, and it is possible to prevent an increase in the load of the playback process.

[0160] <2-10-2. Syntax example 2> In <2-10-1. Syntax Example 1>, the information for obtaining a tile has been described as tile identification information (tile_id), but the information for obtaining this tile may instead be tile track identification information (tile_track_id). By applying tile track identification information (tile_track_id) instead of tile identification information (tile_id), the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks. An example of the syntax of the dynamic spatial region timed metadata track in this case is described below.

[0161] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to FIG.

[0162] FIG. 26 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample in this case.

[0163] As shown in the fifth to ninth lines from the top of the syntax shown in FIG. 26 , in this DynamicGPCC3DSpatialRegionSample, if the value of the static_tile_mapping flag is “0 (false),” the identification information (tile_track_id) of the G-PCC tile track in which the tiles constituting the 3D spatial region are stored is specified for each 3D spatial region included in the sample. That is, in this case, the DynamicGPCC3DSpatialRegionSample includes a list of the identification information (tile_track_id) of the G-PCC tile track corresponding to each 3D spatial region of the sample. In contrast, if the value of the static_tile_mapping flag is “1 (true),” the specification of the identification information (tile_track_id) of the G-PCC tile track is omitted. That is, in this case, the DynamicGPCC3DSpatialRegionSample does not include a list of the identification information (tile_track_id) of the G-PCC tile track corresponding to each 3D spatial region of the sample.

[0164] This makes it possible to prevent unnecessary information from being stored in the dynamic spatial region timed metadata. Therefore, it is possible to prevent an increase in the amount of information in the dynamic spatial region timed metadata, and therefore an increase in the amount of information in the G-PCC file. Therefore, it is possible to prevent an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, it becomes easier to parse the dynamic spatial region timed metadata, and it is possible to prevent an increase in the load of the playback process.

[0165] <2-11.static_mapping> In <2-10.static_tile_mapping>, we have described a case where the first information is information (static_tile_mapping flag) that indicates whether the correspondence between a 3D spatial region and information for obtaining tiles of a point cloud is static in the time direction, but the first information is not limited to this example.

[0166] When applying method 1-4, as shown in the tenth row from the top of the table in Fig. 13, the first information may be information (static_mapping flag) indicating whether the spatial positional relationship between 3D spatial regions and the correspondence relationship between the 3D spatial region and the information for obtaining the tile are static in the time direction (method 1-4-2). In other words, if the value of the static_mapping flag is "1," the second information (DynamicGPCC3DSpatialRegionSample) may not include (store) information indicating the correspondence relationship between the 3D spatial region and the information for obtaining the tile.

[0167] For example, a first information generation unit of an information processing device may generate, as the first information, information (static_mapping flag) indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles is static in the time direction.

[0168] In addition, the first information stored in the G-PCC file may be information (static_mapping flag) indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles is static in the time direction.

[0169] <2-11-1. Syntax example 1> In this case, for example, the first information and the second information may be stored in the dynamic spatial region timed metadata track of the G-PCC file. An example of the syntax of the dynamic spatial region timed metadata track is described below. Note that, here, it is assumed that the information for obtaining a tile is tile identification information (tile_id).

[0170] FIG. 27 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSampleEntry stored in the sample entry of the dynamic spatial region timed metadata track.

[0171] As shown in the fifth line from the top of the syntax shown in FIG. 27, this DynamicGPCC3DSpatialRegionSampleEntry stores a static_mapping flag (first information).

[0172] FIG. 28 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample stored in the dynamic spatial region timed metadata track.

[0173] As shown in the fifth to ninth lines from the top of the syntax shown in FIG. 28 , in this DynamicGPCC3DSpatialRegionSample, if the value of the static_mapping flag is “0 (false),” identification information (tile_id) of the tile corresponding to the 3D spatial region (i.e., the tiles constituting the 3D spatial region) is specified for each 3D spatial region included in the sample. That is, in this case, the DynamicGPCC3DSpatialRegionSample includes a list of tile identification information (tile_id) corresponding to each 3D spatial region of the sample. In contrast, if the value of the static_mapping flag is “1 (true),” the specification of the tile identification information (tile_id) is omitted. That is, if the value of the static_mapping flag is “1 (true),” the DynamicGPCC3DSpatialRegionSample does not include a list of tile identification information (tile_id) corresponding to each 3D spatial region of the sample.

[0174] This makes it possible to prevent unnecessary information from being stored in the dynamic spatial region timed metadata. Therefore, it is possible to prevent an increase in the amount of information in the dynamic spatial region timed metadata, and therefore an increase in the amount of information in the G-PCC file. Therefore, it is possible to prevent an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, it becomes easier to parse the dynamic spatial region timed metadata, and it is possible to prevent an increase in the load of the playback process.

[0175] <2-11-2. Syntax example 2> In <2-11-1. Syntax Example 1>, the information for obtaining a tile has been described as tile identification information (tile_id), but the information for obtaining this tile may instead be tile track identification information (tile_track_id). By applying tile track identification information (tile_track_id) instead of tile identification information (tile_id), the playback device can easily identify the G-PCC tile track that stores the data of tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks. An example of the syntax of the dynamic spatial region timed metadata track in this case is described below.

[0176] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to FIG.

[0177] FIG. 29 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample in this case.

[0178] As shown in the fifth to ninth lines from the top of the syntax shown in FIG. 29 , in this DynamicGPCC3DSpatialRegionSample, if the value of the static_mapping flag is “0 (false),” the identification information (tile_track_id) of the G-PCC tile track in which the tiles constituting the 3D spatial region are stored is specified for each 3D spatial region included in the sample. That is, in this case, the DynamicGPCC3DSpatialRegionSample includes a list of the identification information (tile_track_id) of the G-PCC tile track corresponding to each 3D spatial region of the sample. In contrast, if the value of the static_mapping flag is “1 (true),” the specification of the identification information (tile_track_id) of the G-PCC tile track is omitted. That is, in this case, the DynamicGPCC3DSpatialRegionSample does not include a list of the identification information (tile_track_id) of the G-PCC tile track corresponding to each 3D spatial region of the sample.

[0179] This makes it possible to prevent unnecessary information from being stored in the dynamic spatial region timed metadata. Therefore, it is possible to prevent an increase in the amount of information in the dynamic spatial region timed metadata, and therefore an increase in the amount of information in the G-PCC file. Therefore, it is possible to prevent an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, it becomes easier to parse the dynamic spatial region timed metadata, and it is possible to prevent an increase in the load of the playback process.

[0180] <2-12. Number of static 3D spatial regions> In each of the above examples, for example, as shown in the second line from the top of the syntax in Fig. 29, the number of 3D spatial regions (num_regions) is specified for each sample in DynamicGPCC3DSpatialRegionSample. In other words, DynamicGPCC3DSpatialRegionSample includes the number of dynamic 3D spatial regions. However, DynamicGPCC3DSpatialRegionSample may not include the number of dynamic 3D spatial regions.

[0181] When Method 1-4 is applied, as shown in the 11th row from the top of the table in Figure 13, if the first information is true, the second information (DynamicGPCC3DSpatialRegionSample) may include the static number of 3D spatial regions instead of the dynamic number of 3D spatial regions (Method 1-4-3). Because the number of G-PCC tile tracks is static in the G-PCC file, num_regions is also static in order for the correspondence between 3D spatial regions and G-PCC tile tracks to be static.

[0182] For example, the second information generating unit of the information processing device may generate information about dynamic three-dimensional space regions that further includes information indicating the number of static three-dimensional space regions.

[0183] The second information stored in the G-PCC file may be information about dynamic three-dimensional spatial regions, further including information indicating the number of static three-dimensional spatial regions. An extraction unit of the information processing device may then extract, from the file, data on tiles that constitute the three-dimensional spatial regions that will form the point cloud, based on the information about the dynamic three-dimensional spatial regions and information indicating the static correspondence between the three-dimensional spatial regions and information for obtaining tiles.

[0184] When this method 1-4-3 is applied, the first information may be information indicating whether the correspondence between the 3D spatial region and the information for obtaining the tile is static (static_tile_mapping flag), or information indicating the spatial positional relationship between the 3D spatial regions and whether the correspondence between the 3D spatial region and the information for obtaining the tile is static (static_mapping flag). Furthermore, the information for obtaining the tile may be tile identification information (tile_id) or tile track identification information (tile_track_id).

[0185] <2-12-1. Syntax example 1> Here, the first information is information indicating whether the correspondence between the 3D spatial region and the information for obtaining a tile is static (static_tile_mapping flag), and the information for obtaining a tile is tile identification information (tile_id).

[0186] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to FIG.

[0187] FIG. 30 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample stored in the dynamic spatial region timed metadata track.

[0188] As shown in the second to sixth lines from the top of the syntax shown in FIG. 30, in this DynamicGPCC3DSpatialRegionSample, if the value of the static_tile_mapping flag is "0 (false)," the number of 3D spatial regions (num_regions_dynamic) of the sample is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of dynamic 3D spatial regions. On the other hand, if the value of the static_tile_mapping flag is "1 (true)," the number of static 3D spatial regions (num_regions) is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of static 3D spatial regions.

[0189] If the value of the static_tile_mapping flag is "1", each entry in the NumRegions loop of that sample updates the information of the 3DSpatialRegionStruct of the entry with the same index in the num_regions loop of the GPCCSpatialRegionBox of the immediately preceding sample or sample entry. You may also update the information of the 3DSpatialRegionStruct with the same 3d_region_id stored in the 3DSpatialRegionStruct.

[0190] By doing so, if the first information is true, the number of 3D spatial regions stored in the dynamic spatial region timed metadata becomes static in accordance with the static correspondence between the 3D spatial regions and the G-PCC tile tracks. This eliminates the need to check the number of 3D spatial regions for each sample, making it easier to parse the dynamic spatial region timed metadata and reducing the load on the playback process.

[0191] Also, in the DynamicGPCC3DSpatialRegionSample in the example of Fig. 30, when the value of the static_tile_mapping flag is "1 (true)", the specification of tile identification information (tile_id) is omitted, as in the case of Fig. 25. In other words, when the value of the static_tile_mapping flag is "1 (true)", this DynamicGPCC3DSpatialRegionSample does not include a list of tile identification information (tile_id) corresponding to each 3D spatial region of the sample.

[0192] This prevents unnecessary information from being stored in the dynamic spatial region timed metadata. This prevents an increase in the amount of information in the dynamic spatial region timed metadata, and thus prevents an increase in the amount of information in the G-PCC file. This prevents an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, parsing the dynamic spatial region timed metadata becomes easier, and prevents an increase in the load of the playback process.

[0193] <2-12-2. Syntax example 2> Here, the first information is information (static_tile_mapping flag) indicating whether the correspondence between the 3D spatial region and the information for obtaining tiles is static, and the information for obtaining tiles is tile track identification information (tile_track_id). By applying the tile track identification information (tile_track_id) instead of the tile identification information (tile_id), the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks.

[0194] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to FIG.

[0195] FIG. 31 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample stored in the dynamic spatial region timed metadata track.

[0196] In the example of FIG. 31, as in the example of FIG. 30, if the value of the static_tile_mapping flag is "0 (false)," the number of 3D spatial regions (num_regions_dynamic) of the sample is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of dynamic 3D spatial regions. On the other hand, if the value of the static_tile_mapping flag is "1 (true)," the number of static 3D spatial regions (num_regions) is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of static 3D spatial regions.

[0197] If the value of the static_tile_mapping flag is "1", each entry in the NumRegions loop of that sample updates the information of the 3DSpatialRegionStruct of the entry with the same index in the num_regions loop of the GPCCSpatialRegionBox of the immediately preceding sample or sample entry. You may also update the information of the 3DSpatialRegionStruct with the same 3d_region_id stored in the 3DSpatialRegionStruct.

[0198] By doing so, if the first information is true, the number of 3D spatial regions stored in the dynamic spatial region timed metadata becomes static in accordance with the static correspondence between the 3D spatial regions and the G-PCC tile tracks. This eliminates the need to check the number of 3D spatial regions for each sample, making it easier to parse the dynamic spatial region timed metadata and reducing the load on the playback process.

[0199] Furthermore, in the DynamicGPCC3DSpatialRegionSample in the example of Fig. 31, when the value of the static_tile_mapping flag is "1 (true)", the specification of tile track identification information (tile_track_id) is omitted, as in the case of Fig. 26. In other words, when the value of the static_tile_mapping flag is "1 (true)", this DynamicGPCC3DSpatialRegionSample does not include a list of tile track identification information (tile_track_id) corresponding to each 3D spatial region of the sample.

[0200] This prevents unnecessary information from being stored in the dynamic spatial region timed metadata. This prevents an increase in the amount of information in the dynamic spatial region timed metadata, and thus prevents an increase in the amount of information in the G-PCC file. This prevents an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, parsing the dynamic spatial region timed metadata becomes easier, and prevents an increase in the load of the playback process.

[0201] <2-12-3. Syntax example 3> Here, the first information is information (static_mapping flag) indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles is static in the time direction, and the information for obtaining tiles is tile track identification information (tile_id).

[0202] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to FIG.

[0203] FIG. 32 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample stored in the dynamic spatial region timed metadata track.

[0204] As shown in the second to sixth lines from the top of the syntax shown in FIG. 32, in this DynamicGPCC3DSpatialRegionSample, if the value of the static_mapping flag is "0 (false)," the number of 3D spatial regions (num_regions_dynamic) of the sample is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of dynamic 3D spatial regions. On the other hand, if the value of the static_mapping flag is "1 (true)," the number of static 3D spatial regions (num_regions) is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of static 3D spatial regions.

[0205] If the value of the static_mapping flag is "1", each entry in the NumRegions loop of that sample updates the information of the 3DSpatialRegionStruct of the entry with the same index in the num_regions loop of the GPCCSpatialRegionBox of the immediately preceding sample or sample entry. You may also update the information of the 3DSpatialRegionStruct with the same 3d_region_id stored in the 3DSpatialRegionStruct.

[0206] By doing so, if the first information is true, the number of 3D spatial regions stored in the dynamic spatial region timed metadata becomes static in accordance with the static correspondence between the 3D spatial regions and the G-PCC tile tracks. This eliminates the need to check the number of 3D spatial regions for each sample, making it easier to parse the dynamic spatial region timed metadata and reducing the load on the playback process.

[0207] Also, in the DynamicGPCC3DSpatialRegionSample in the example of Fig. 32, when the value of the static_mapping flag is "1 (true)", the specification of tile identification information (tile_id) is omitted, as in the case of Fig. 25. In other words, when the value of the static_mapping flag is "1 (true)", this DynamicGPCC3DSpatialRegionSample does not include a list of tile identification information (tile_id) corresponding to each 3D spatial region of the sample.

[0208] This prevents unnecessary information from being stored in the dynamic spatial region timed metadata. This prevents an increase in the amount of information in the dynamic spatial region timed metadata, and thus prevents an increase in the amount of information in the G-PCC file. This prevents an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, parsing the dynamic spatial region timed metadata becomes easier, and prevents an increase in the load of the playback process.

[0209] <2-12-4. Syntax example 4> Here, the first information is information (static_mapping flag) indicating whether the spatial positional relationship between 3D spatial regions and the correspondence between the 3D spatial regions and the information for obtaining tiles is static in the time direction, and the information for obtaining tiles is tile track identification information (tile_track_id). By applying the tile track identification information (tile_track_id) instead of the tile identification information (tile_id), the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC Tile Sample Entries (GPCCTileSampleEntry) of all G-PCC tile tracks.

[0210] In this case, the syntax of DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to FIG.

[0211] FIG. 33 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSample stored in the dynamic spatial region timed metadata track.

[0212] In the example of FIG. 33, as in the example of FIG. 32, if the value of the static_mapping flag is "0 (false)," the number of 3D spatial regions (num_regions_dynamic) of the sample is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of dynamic 3D spatial regions. On the other hand, if the value of the static_mapping flag is "1 (true)," the number of static 3D spatial regions (num_regions) is set. That is, in this case, DynamicGPCC3DSpatialRegionSample includes the number of static 3D spatial regions.

[0213] If the value of the static_mapping flag is "1", each entry in the NumRegions loop of that sample updates the information of the 3DSpatialRegionStruct of the entry with the same index in the num_regions loop of the GPCCSpatialRegionBox of the immediately preceding sample or sample entry. You may also update the information of the 3DSpatialRegionStruct with the same 3d_region_id stored in the 3DSpatialRegionStruct.

[0214] By doing so, if the first information is true, the number of 3D spatial regions stored in the dynamic spatial region timed metadata becomes static in accordance with the static correspondence between the 3D spatial regions and the G-PCC tile tracks. This eliminates the need to check the number of 3D spatial regions for each sample, making it easier to parse the dynamic spatial region timed metadata and reducing the load on the playback process.

[0215] Furthermore, in the DynamicGPCC3DSpatialRegionSample in the example of Fig. 33, when the value of the static_mapping flag is "1 (true)", the specification of tile track identification information (tile_track_id) is omitted, as in the case of Fig. 29. In other words, when the value of the static_mapping flag is "1 (true)", this DynamicGPCC3DSpatialRegionSample does not include a list of tile track identification information (tile_track_id) corresponding to each 3D spatial region of the sample.

[0216] This prevents unnecessary information from being stored in the dynamic spatial region timed metadata. This prevents an increase in the amount of information in the dynamic spatial region timed metadata, and thus prevents an increase in the amount of information in the G-PCC file. This prevents an increase in the processing load related to the transmission of the G-PCC file and an increase in the bandwidth load of the communication path. Furthermore, parsing the dynamic spatial region timed metadata becomes easier, and prevents an increase in the load of the playback process.

[0217] <2-13. Combinations> When Method 1 is applied, any of Methods 1-1 to 1-3 described above may be applied in combination with Method 1-4 (Method 1-5), as shown in the 12th row from the top of the table in FIG. 13.

[0218] <2-13-1. Combination example 1> For example, Syntax Example 2 of Method 1-1-1 and Syntax Example 2 of Method 1-4-3 may be combined.

[0219] FIG. 34 is a diagram showing an example of the syntax of DynamicGPCC3DSpatialRegionSampleEntry stored in the sample entry of the dynamic spatial region timed metadata track.

[0220] As shown in the fifth and sixth lines from the top of the syntax shown in Fig. 34, the static_region_relation flag and the static_tile_mapping flag are stored as first information in this DynamicGPCC3DSpatialRegionSampleEntry. Also, as shown in the eighth and ninth lines from the top of the syntax shown in Fig. 34, if the value of the static_region_relation flag is "1", a 3DBoundingSpaceStruct (second information) is stored in DynamicGPCC3DSpatialRegionSampleEntry.

[0221] In this case, the syntax of DynamicGPCC3DSpatialRegionSample is the same as the example described with reference to Fig. 31. Also, the syntax of 3DBoundingSpaceStruct is the same as the example described with reference to Fig. 18.

[0222] That is, in this case, the static_region_relation flag and the static_tile_mapping flag (first information) are stored in the DynamicGPCC3DSpatialRegionSampleEntry. Also, if the value of the static_region_relation flag is "1", the 3DBoundingSpaceStruct (second information) as described with reference to FIG. 18 is stored in the DynamicGPCC3DSpatialRegionSampleEntry.

[0223] Therefore, based on this information, the playback device can easily determine whether the spatial positional relationship between 3D spatial regions is static, and can easily grasp the spatial positional relationship between those 3D spatial regions. Therefore, the playback device can play back the 3D spatial region to be played back, the tiles that make up that 3D spatial region, the tiles stored in the G-PCC tile track, and other information without checking each frame.

[0224] Also, as shown in FIG. 31, in the second information, DynamicGPCC3DSpatialRegionSample, if the value of the static_tile_mapping flag is “1 (true)”, the sample does not include a list of tile track identification information (tile_track_id) corresponding to each 3D spatial region of the sample.

[0225] This prevents unnecessary information from being stored in the dynamic spatial region timed metadata. This prevents an increase in the amount of information in the dynamic spatial region timed metadata, and thus prevents an increase in the amount of information in the G-PCC file. This prevents an increase in the processing load related to the transmission of the G-PCC file and the bandwidth load on the communication path. Furthermore, parsing the dynamic spatial region timed metadata becomes easier.

[0226] Furthermore, by applying tile track identification information (tile_track_id) instead of tile identification information (tile_id), the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks.

[0227] As described above, in this case as well, it is possible to suppress an increase in the load of the reproduction process.

[0228] <2-13-2. Combination example 2> For example, Syntax Example 2 of Method 1-1-2 and Syntax Example 4 of Method 1-4-3 may be combined.

[0229] In this case, DynamicGPCC3DSpatialRegionSampleEntry is the same as the example described with reference to Fig. 20. Also, the syntax of DynamicGPCC3DSpatialRegionSample is the same as the example described with reference to Fig. 33. Also, the syntax of 3DBoundingSpaceStruct is the same as the example described with reference to Fig. 18.

[0230] That is, in this case, the static_mapping flag (first information) is stored in the DynamicGPCC3DSpatialRegionSampleEntry. Also, if the value of the static_mapping flag is "1", the 3DBoundingSpaceStruct (second information) as described with reference to FIG. 18 is stored in the DynamicGPCC3DSpatialRegionSampleEntry.

[0231] Therefore, based on this information, the playback device can easily determine whether the spatial positional relationship between 3D spatial regions is static, and can easily grasp the spatial positional relationship between those 3D spatial regions. Therefore, the playback device can play back the 3D spatial region to be played back, the tiles that make up that 3D spatial region, the tiles stored in the G-PCC tile track, and other information without checking each frame.

[0232] Also, as shown in FIG. 33, in the second information, DynamicGPCC3DSpatialRegionSample, if the value of the static_mapping flag is “1 (true)”, a list of tile track identification information (tile_track_id) corresponding to each 3D spatial region of the sample is not included.

[0233] This prevents unnecessary information from being stored in the dynamic spatial region timed metadata. This prevents an increase in the amount of information in the dynamic spatial region timed metadata, and thus prevents an increase in the amount of information in the G-PCC file. This prevents an increase in the processing load related to the transmission of the G-PCC file and the bandwidth load on the communication path. Furthermore, parsing the dynamic spatial region timed metadata becomes easier.

[0234] Furthermore, by applying tile track identification information (tile_track_id) instead of tile identification information (tile_id), the playback device can easily identify the G-PCC tile track that stores the data of the tiles that make up the desired 3D spatial region, without having to parse the GPCC tile sample entries (GPCCTileSampleEntry) of all G-PCC tile tracks.

[0235] As described above, in this case as well, it is possible to suppress an increase in the load of the reproduction process.

[0236] <3. Information transmission using MPD> Note that the present technology can also be applied to, for example, MPEG-DASH (Moving Picture Experts Group phase - Dynamic Adaptive Streaming over HTTP). For example, as shown in the thirteenth row from the top of the table shown in Fig. 13, in MPEG-DASH, the first information described above may be stored in an MPD (Media Presentation Description), which is a control file that stores control information related to bitstream distribution, and transmitted (Method 2).

[0237] For example, a file generation unit of the information processing device may generate a control file that controls the playback of the file, and store the first information in the control file.

[0238] In addition, the extraction unit of the information processing device may refer to first information stored in a control file that controls the playback of the file, and if the relationship between independently decodable three-dimensional spatial regions of the point cloud is static, extract tile data from the file based on second information stored in the file.

[0239] For example, in the MPD, a descriptor that stores the first information (e.g., a dynamic spatial region descriptor) may be defined and stored in an adaptation set corresponding to the dynamic spatial region timed metadata. Also, the spatialRegion element of the GPCCSpatialRegions descriptor may be stored in this descriptor as the initial value of the dynamic spatial region.

[0240] Furthermore, as shown in the example of FIG. 35, the GPCCSpatialRegions descriptor may be extended to add an @staticMapping element that indicates whether the spatial positional relationship of 3D spatial regions and the correspondence relationship between the 3D spatial regions and the Adaptation Set are static. That is, the @staticMapping element indicates the value of the static_mapping flag (first information) described above. As shown in FIG. 35, when the value of this @staticMapping element is "0," the spatial positional relationship of each 3D spatial region is dynamic, and the correspondence relationship between the 3D spatial region and the Adaptation Set is dynamic. When the value of the @staticMapping element is "1," the spatial positional relationship of each 3D spatial region is static, and the correspondence relationship between the 3D spatial region and the Adaptation Set is static.

[0241] Alternatively, instead of the @staticMapping element, an @staticRegionRelation element indicating whether the spatial positional relationship of the 3D spatial region is static and an @staticTileMapping element indicating whether the correspondence relationship between the 3D spatial region and the Adaptation Set that references the G-PCC tile track is static may be provided. In other words, the @staticRegionRelation element indicates the value of the static_region_relation flag (first information) described above, and the @staticTileMapping element indicates the static_tile_mapping flag (first information) described above.

[0242] In this case, the playback device acquires data of tiles that make up the 3D spatial region in which the point cloud is constructed, based on the first information and the second information in the MPD. Therefore, the playback device does not need to check the correspondence between the 3D spatial region and the track for each sample, and can suppress an increase in the load of the playback process.

[0243] <4. Information transmission using Matryoshka media container> Although the above has described an example in which ISOBMFF is used as the file format, the file in which the G-PCC bitstream is stored may be any file format other than ISOBMFF. For example, as shown in the bottom row of the table in Fig. 13, the G-PCC bitstream may be stored in a Matroska Media Container (Method 3). An example of the main configuration of a Matroska Media Container is shown in Fig. 36.

[0244] In this case, for example, the first information and the second information may be stored as newly defined elements under the Track Entry element. Also, when the first information and the second information are stored in timed metadata, the timed metadata may be stored in a Track entry different from the Track entry in which the G-PCC bitstream is stored.

[0245] 5. First Embodiment <5-1. File Generation Device> The present technology described above can be applied to any device. Fig. 37 is a block diagram showing an example of the configuration of a file generation device, which is one aspect of an information processing device to which the present technology is applied. The file generation device 300 shown in Fig. 37 is a device that encodes point cloud data by applying G-PCC and stores the G-PCC bitstream generated by the encoding in an ISOBMFF (G-PCC file).

[0246] The file generation device 300 applies the above-described present technology and stores the G-PCC bitstream in a G-PCC file so as to enable partial access. That is, the file generation device 300 stores, in the G-PCC file, first information regarding changes in relationships between independently decodable three-dimensional spatial regions of a point cloud representing a three-dimensional object, and second information regarding the three-dimensional spatial region generated according to the first information.

[0247] Note that Fig. 37 shows the main processing units, data flows, etc., and does not necessarily include everything shown in Fig. 37. In other words, file generation device 300 may have processing units that are not shown as blocks in Fig. 37, or processes or data flows that are not shown as arrows, etc. in Fig. 37.

[0248] 37, file generation device 300 has an extraction unit 311, an encoding unit 312, a bitstream generation unit 313, a first information generation unit 314, a second information generation unit 315, and a file generation unit 316. In addition, encoding unit 312 has a geometry encoding unit 321, an attribute encoding unit 322, and a metadata generation unit 323.

[0249] The extraction unit 311 extracts geometry data and attribute data from the point cloud data input to the file generation device 300. The extraction unit 311 supplies the extracted geometry data to a geometry encoding unit 321 of the encoding unit 312. The extraction unit 311 also supplies the extracted attribute data to an attribute encoding unit 322 of the encoding unit 312.

[0250] The encoding unit 312 encodes the point cloud data. The geometry encoding unit 321 encodes the geometry data supplied from the extraction unit 311 to generate a geometry bitstream. The geometry encoding unit 321 supplies the generated geometry bitstream to the metadata generation unit 323. The geometry encoding unit 321 also supplies the generated geometry bitstream to the attribute encoding unit 322.

[0251] The attribute encoding unit 322 encodes the attribute data supplied from the extraction unit 311 to generate an attribute bitstream. The attribute encoding unit 322 supplies the generated attribute bitstream to the metadata generation unit 323.

[0252] The metadata generation unit 323 generates metadata by referring to the supplied geometry bitstream and attribute bitstream, and supplies the generated metadata to the bitstream generation unit 313 together with the geometry bitstream and attribute bitstream.

[0253] The bitstream generator 313 multiplexes the supplied geometry bitstream, attribute bitstream, and metadata to generate a G-PCC bitstream. The bitstream generator 313 supplies the generated G-PCC bitstream to the first information generator 314.

[0254] The first information generation unit 314 applies the present technology described above in <2. Information transmission based on temporal changes in relationships for a 3D spatial region> and generates first information regarding changes in relationships for an independently decodable 3D spatial region of a point cloud representing a 3D-shaped object based on the provided G-PCC bitstream. In this case, the first information generation unit 314 can apply any of the methods described above in <2. Information transmission based on temporal changes in relationships for a 3D spatial region>. The first information generation unit 314 provides the generated first information to the second information generation unit 315 together with the G-PCC bitstream.

[0255] The second information generation unit 315 applies the present technology described above in <Information transmission based on temporal changes in relationships for a 2.3D spatial region> to generate second information about the 3D spatial region based on the provided G-PCC bitstream and first information. In this case, the second information generation unit 315 can apply any of the methods described above in <Information transmission based on temporal changes in relationships for a 2.3D spatial region>. The second information generation unit 315 provides the generated second information to the file generation unit 316 together with the G-PCC bitstream and the first information.

[0256] The file generation unit 316 applies the present technology described above in <Information transmission based on temporal changes in relationships between 2.3D spatial regions> to generate a G-PCC file that stores the supplied G-PCC bitstream, first information, and second information. In this case, the file generation unit 316 can apply any of the methods described above in <Information transmission based on temporal changes in relationships between 2.3D spatial regions>. The file generation unit 316 outputs the G-PCC file generated as described above to the outside of the file generation device 300.

[0257] With this configuration, the file generation device 300 can suppress an increase in the load of the playback process, as described above in <2. Information transmission based on changes in the relationship in the time direction for 3D spatial regions>.

[0258] <5-2. File generation process flow> An example of the flow of the file generation process executed by this file generation device 300 will be described with reference to the flowchart of FIG.

[0259] When the file generation process starts, the extraction unit 311 of the file generation device 300 extracts geometry and attributes from the point cloud in step S301.

[0260] In step S302, the encoding unit 312 encodes the geometry and attributes extracted in step S301 to generate a geometry bitstream and an attribute bitstream, and further generates metadata for the encoded geometry and attribute bitstream.

[0261] In step S303, the bitstream generation unit 313 multiplexes the geometry bitstream, attribute bitstream, and metadata generated in step S302 to generate a G-PCC bitstream.

[0262] In step S304, the first information generation unit 314 applies the present technology described above in <2. Information transmission based on temporal changes in relationships for 3D spatial regions> to generate first information regarding changes in relationships for independently decodable 3D spatial regions of the point cloud representing a 3D-shaped object, based on the G-PCC bitstream generated in step S303. In this case, the first information generation unit 314 can apply any of the methods described above in <2. Information transmission based on temporal changes in relationships for 3D spatial regions>.

[0263] In step S305, the second information generation unit 315 applies the present technology described above in <2. Information transmission based on a change in the relationship between 3D spatial regions in the time direction> to generate second information about the three-dimensional spatial region in accordance with the first information generated in step S304. In this case, the second information generation unit 315 can apply any method described above in <2. Information transmission based on a change in the relationship between 3D spatial regions in the time direction>.

[0264] In step S306, the file generation unit 316 generates other information and applies the present technology described above in <2. Information transmission based on temporal changes in relationships for 3D spatial regions> to generate a G-PCC file that stores the G-PCC bitstream, the first information, and the second information.

[0265] When the process of step S306 is completed, the file generation process ends.

[0266] As described above, in the file generation process, the file generation device 300 applies the present technology described in <Information transmission based on changes in the relationship between 2.3D spatial regions in the time direction> to generate the first information and the second information and store them in a G-PCC file. By doing so, the file generation device 300 can suppress an increase in the load of the playback process, as described above in <Information transmission based on changes in the relationship between 2.3D spatial regions in the time direction>.

[0267] 6. Second Embodiment <6-1. Playback device> Fig. 39 is a block diagram showing an example of the configuration of a playback device, which is one aspect of an information processing device to which the present technology is applied. The playback device 400 shown in Fig. 39 is a device that decodes a G-PCC file, constructs a point cloud, and performs rendering to generate presentation information. In this case, the playback device 400 applies the above-described present technology to extract data of tiles that constitute a desired 3D spatial region of the point cloud from the G-PCC file, and decodes and plays back the extracted information. In other words, the playback device 400 can decode and play back only a portion of the point cloud.

[0268] Note that Fig. 39 shows the main processing units, data flows, etc., and does not necessarily include everything. In other words, playback device 400 may have processing units that are not shown as blocks in Fig. 39, or may have processing or data flows that are not shown as arrows, etc. in Fig. 39.

[0269] 39, the playback device 400 has a control unit 401, a file acquisition unit 411, a playback processing unit 412, and a presentation processing unit 413. The playback processing unit 412 has a file processing unit 421, a decoding unit 422, and a presentation information generation unit 423.

[0270] The control unit 401 controls each processing unit in the playback device 400. The file acquisition unit 411 acquires a G-PCC file that stores the point cloud to be played back, and supplies it to (the file processing unit 421 of) the playback processing unit 412. The playback processing unit 412 performs processing related to the playback of the point cloud stored in the supplied G-PCC file.

[0271] The file processing unit 421 of the playback processing unit 412 acquires the G-PCC file supplied from the file acquisition unit 411 and extracts a bitstream from the G-PCC file. At this time, the file processing unit 421 applies the present technology described above in <2. Information Transmission Based on Temporal Changes in Relationships for 3D Spatial Regions> to extract data (bitstream) of tiles constituting a desired 3D spatial region from the G-PCC file. The file processing unit 421 supplies the extracted bitstream to the decoding unit 422. The decoding unit 422 decodes the supplied bitstream and generates geometry and attribute data. The decoding unit 422 supplies the generated geometry and attribute data to the presentation information generation unit 423. The presentation information generation unit 423 constructs a point cloud using the supplied geometry and attribute data and generates presentation information for presenting (e.g., displaying) the point cloud. For example, the presentation information generation unit 423 performs rendering using the point cloud and generates, as presentation information, a display image of the point cloud viewed from a predetermined viewpoint. The presentation information generation unit 423 supplies the presentation information thus generated to the presentation processing unit 413 .

[0272] The presentation processing unit 413 performs processing to present the supplied presentation information. For example, the presentation processing unit 413 supplies the presentation information to a display device or the like external to the playback device 400, and causes the presentation information to be presented.

[0273] <6-2. Playback Processing Unit> Fig. 40 is a block diagram showing an example of the main configuration of the playback processing unit 412. As shown in Fig. 40, the file processing unit 421 has a bitstream extraction unit 431. The decoding unit 422 has a geometry decoding unit 441 and an attribute decoding unit 442. The presentation information generation unit 423 has a point cloud construction unit 451 and a presentation processing unit 452.

[0274] The bitstream extraction unit 431 applies the present technology described above in <2. Information Transmission Based on Temporal Changes in Relationships for 3D Spatial Regions> to extract a bitstream from the supplied G-PCC file. For example, the bitstream extraction unit 431 references first information included in the supplied G-PCC file, and if the relationship between the independently decodable 3D spatial region of the point cloud is static, extracts data (bitstream) of tiles constituting the 3D spatial region that constitutes the point cloud based on second information about the 3D spatial region generated in accordance with the first information. In this case, the bitstream extraction unit 431 can apply any of the methods described above in <2. Information Transmission Based on Temporal Changes in Relationships for 3D Spatial Regions>.

[0275] The bitstream extraction unit 431 supplies the extracted geometry bitstream to the geometry decoding unit 441. The bitstream extraction unit 431 also supplies the extracted attribute bitstream to the attribute decoding unit 442.

[0276] The geometry decoding unit 441 decodes the supplied geometry bitstream to generate geometry data. The geometry decoding unit 441 supplies the generated geometry data to the point cloud construction unit 451. The attribute decoding unit 442 decodes the supplied attribute bitstream to generate attribute data. The attribute decoding unit 442 supplies the generated attribute data to the point cloud construction unit 451.

[0277] The point cloud construction unit 451 constructs a point cloud using the supplied geometry and attribute data. That is, the point cloud construction unit 451 can construct desired tiles of the point cloud. The point cloud construction unit 451 supplies the constructed point cloud data to the presentation processing unit 452.

[0278] The presentation processing unit 452 generates presentation information using the supplied point cloud data. The presentation processing unit 452 supplies the generated presentation information to the presentation processing unit 413.

[0279] With this configuration, the playback device 400 can suppress an increase in the load of playback processing, as described above in <2. Information transmission based on changes in the relationship in the time direction for 3D spatial regions>.

[0280] <6-3. Reclaiming process flow> An example of the flow of the playback process executed by this playback device 400 will be described with reference to the flowchart of FIG.

[0281] When the playback process starts, the file acquisition unit 411 of the playback device 400 acquires the G-PCC file to be played back in step S401.

[0282] In step S402, the bitstream extraction unit 431 applies the present technology described above in <2. Information transmission based on temporal changes in the relationship between 3D spatial regions> to extract a bitstream from the G-PCC file acquired in step S401. For example, the bitstream extraction unit 431 references first information included in the provided G-PCC file, and if the relationship between an independently decodable 3D spatial region of the point cloud is static, extracts data (bitstream) of tiles constituting the 3D spatial region that constitutes the point cloud based on second information about the 3D spatial region generated in accordance with the first information. In this case, the bitstream extraction unit 431 can apply any method described above in <2. Information transmission based on temporal changes in the relationship between 3D spatial regions>.

[0283] In step S403, the geometry decoding unit 441 of the decoding unit 422 decodes the geometry bitstream extracted in step S402 to generate geometry data, and the attribute decoding unit 442 decodes the attribute bitstream extracted in step S402 to generate attribute data.

[0284] In step S404, the point cloud construction unit 451 constructs a point cloud using the geometry and attribute data generated in step S403. That is, the point cloud construction unit 451 can construct a desired tile (a part of the point cloud).

[0285] In step S405, the presentation processing unit 452 generates presentation information by performing rendering using the point cloud constructed in step S404, etc. The presentation processing unit 413 supplies the presentation information to an external device outside the playback device 400, where it is presented.

[0286] When the process of step S405 ends, the playback process ends.

[0287] As described above, in the playback process, the playback device 400 applies the present technology described in <Information transmission based on temporal changes in relationships between 2.3D spatial regions> to extract, from the G-PCC file, data (bit streams) of tiles that constitute a three-dimensional spatial region in which a point cloud is constructed, based on the first information and the second information. By doing so, the playback device 400 can suppress an increase in the load of the playback process, as described above in <Information transmission based on temporal changes in relationships between 2.3D spatial regions>.

[0288] <7. Notes> <Computer> The above-described series of processes can be executed by hardware or software. When the series of processes is executed by software, the programs constituting the software are installed on a computer. Here, the term "computer" includes computers built into dedicated hardware, and general-purpose personal computers, etc., that can execute various functions by installing various programs.

[0289] FIG. 42 is a block diagram showing an example of the hardware configuration of a computer that executes the above-described series of processes by a program.

[0290] In a computer 900 shown in FIG. 42, a CPU (Central Processing Unit) 901, a ROM (Read Only Memory) 902, and a RAM (Random Access Memory) 903 are interconnected via a bus 904.

[0291] An input / output interface 910 is also connected to the bus 904. To the input / output interface 910, an input unit 911, an output unit 912, a storage unit 913, a communication unit 914, and a drive 915 are connected.

[0292] The input unit 911 includes, for example, a keyboard, a mouse, a microphone, a touch panel, an input terminal, etc. The output unit 912 includes, for example, a display, a speaker, an output terminal, etc. The storage unit 913 includes, for example, a hard disk, a RAM disk, a non-volatile memory, etc. The communication unit 914 includes, for example, a network interface. The drive 915 drives removable media 921 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory.

[0293] In a computer configured as above, the CPU 901 performs the above-described series of processes by, for example, loading a program stored in the storage unit 913 into the RAM 903 via the input / output interface 910 and the bus 904 and executing the program. The RAM 903 also stores data necessary for the CPU 901 to execute various processes as appropriate.

[0294] The program executed by the computer can be applied by recording it on removable media 921 such as package media, for example. In this case, the program can be installed in storage unit 913 via input / output interface 910 by inserting removable media 921 into drive 915.

[0295] This program can also be provided via a wired or wireless transmission medium such as a local area network, the Internet, digital satellite broadcasting, etc. In this case, the program can be received by the communication unit 914 and installed in the storage unit 913.

[0296] Alternatively, this program can be installed in advance in the ROM 902 or the storage unit 913 .

[0297] <Applicable targets of this technology> The above description has mainly focused on the application of this technology to a method of storing a G-PCC bitstream in ISOBMFF. However, the application of this technology is arbitrary and is not limited to the above-described examples. In other words, the format of the file storing the G-PCC bitstream is arbitrary and is not limited to the above-described ISOBMFF or Matryoshka Media Container. Furthermore, the encoding and decoding method for 3D data (point cloud) is arbitrary and is not limited to G-PCC. Furthermore, the format of the 3D data is arbitrary and may be other than a point cloud. In other words, as long as it does not contradict the above-described features of this technology, some or all of the specifications of the file, encoding and decoding method, 3D data, and its generation and construction method may differ from those of the above-described examples. Furthermore, some of the processing and specifications described above may be omitted.

[0298] Furthermore, the present technology can be applied to any configuration, for example, various electronic devices.

[0299] Furthermore, for example, the present technology can also be implemented as a part of an apparatus, such as a processor (e.g., a video processor) as a system LSI (Large Scale Integration), a module (e.g., a video module) using multiple processors, a unit (e.g., a video unit) using multiple modules, or a set in which other functions are added to a unit (e.g., a video set).

[0300] Furthermore, for example, the present technology can also be applied to a network system configured with multiple devices. For example, the present technology may be implemented as cloud computing in which multiple devices share and collaborate on processing via a network. For example, the present technology may be implemented in a cloud service that provides image (video)-related services to any terminal, such as a computer, AV (Audio Visual) equipment, a portable information processing terminal, or an IoT (Internet of Things) device.

[0301] In this specification, a system refers to a collection of multiple components (devices, modules (components), etc.), regardless of whether all the components are contained in the same housing. Therefore, multiple devices housed in separate housings and connected via a network, and a single device housed in a single housing with multiple modules, are both systems.

[0302] <Fields and applications where this technology can be applied> Systems, devices, processing units, etc. to which the present technology is applied can be used in any field, for example, transportation, medical care, crime prevention, agriculture, livestock farming, mining, beauty, factories, home appliances, weather, nature monitoring, etc. In addition, their uses are also arbitrary.

[0303] For example, the present technology can be applied to systems and devices used to provide viewing content, etc. Furthermore, for example, the present technology can also be applied to systems and devices used for transportation, such as monitoring traffic conditions and controlling automatic driving. Furthermore, for example, the present technology can also be applied to systems and devices used for security. Furthermore, for example, the present technology can also be applied to systems and devices used for automatic control of machines, etc. Furthermore, for example, the present technology can also be applied to systems and devices used for agriculture and livestock farming. Furthermore, for example, the present technology can also be applied to systems and devices used to monitor natural conditions, such as volcanoes, forests, and oceans, and wildlife. Furthermore, for example, the present technology can also be applied to systems and devices used for sports.

[0304] <Other> In this specification, a "flag" refers to information for identifying multiple states, and includes not only information used to identify two states, true (1) or false (0), but also information capable of identifying three or more states. Therefore, the value that this "flag" can take may be, for example, two values, 1 / 0, or three or more values. In other words, the number of bits constituting this "flag" is arbitrary, and may be one bit or multiple bits. Furthermore, identification information (including flags) can be assumed not only to include the identification information in the bit stream, but also to include difference information of the identification information relative to certain reference information in the bit stream. Therefore, in this specification, "flag" and "identification information" include not only the information itself, but also difference information relative to the reference information.

[0305] Furthermore, various types of information (metadata, etc.) related to the coded data (bitstream) may be transmitted or recorded in any form as long as they are associated with the coded data. Here, the term "associate" means, for example, that one piece of data can be used (linked) when processing the other piece of data. In other words, data associated with each other may be combined into one piece of data or may be individual pieces of data. For example, information associated with coded data (image) may be transmitted over a transmission path separate from that of the coded data (image). Also, for example, information associated with coded data (image) may be recorded on a recording medium separate from that of the coded data (image) (or on a different recording area of ​​the same recording medium). Note that this "association" may refer to only a portion of the data, rather than the entire data. For example, an image and information corresponding to that image may be associated with each other in any unit, such as multiple frames, one frame, or a portion of a frame.

[0306] In this specification, terms such as "composite," "multiplex," "add," "integrate," "include," "store," "embed," "insert," and the like refer to combining multiple items into one, such as combining encoded data and metadata into one piece of data, and refer to one method of "associating" as described above.

[0307] Furthermore, the embodiments of the present technology are not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present technology.

[0308] For example, a configuration described as one device (or processing unit) may be divided and configured as multiple devices (or processing units). Conversely, configurations described above as multiple devices (or processing units) may be combined and configured as one device (or processing unit). Of course, configurations other than those described above may be added to the configuration of each device (or each processing unit). Furthermore, as long as the configuration and operation of the entire system are substantially the same, part of the configuration of one device (or processing unit) may be included in the configuration of another device (or other processing unit).

[0309] Furthermore, for example, the above-described program may be executed in any device, as long as the device has the necessary functions (functional blocks, etc.) and can obtain the necessary information.

[0310] Also, for example, each step of a single flowchart may be executed by one device, or may be shared and executed by multiple devices. Furthermore, when one step includes multiple processes, the multiple processes may be executed by one device, or may be shared and executed by multiple devices. In other words, multiple processes included in one step can be executed as multiple step processes. Conversely, processes described as multiple steps can be executed collectively as one step.

[0311] For example, the steps of a program executed by a computer may be executed in chronological order in the order described herein, or may be executed in parallel or individually at the required timing, such as when a call is made. In other words, as long as no contradiction occurs, the steps may be executed in an order different from the order described above. Furthermore, the steps of this program may be executed in parallel with the processing of another program, or may be executed in combination with the processing of another program.

[0312] Furthermore, for example, multiple technologies related to the present technology can be implemented independently and independently, as long as no contradiction occurs. Of course, any multiple technologies can also be implemented in combination. For example, part or all of the present technology described in any embodiment can be implemented in combination with part or all of the present technology described in another embodiment. Furthermore, part or all of any of the above-described present technologies can be implemented in combination with other technologies not described above.

[0313] The present technology can also be configured as follows. (1) a first information generating unit that generates first information regarding changes in relationships between independently decodable three-dimensional spatial regions of a point cloud representing an object of three-dimensional shape; a second information generating unit that generates second information regarding the three-dimensional space region in accordance with the first information; a file generation unit that generates a file that stores a bit stream of encoded data obtained by encoding the point cloud, the first information, and the second information; An information processing device comprising: (2) the first information generation unit generates, as the first information, information indicating whether the relationship, including a positional relationship in three-dimensional space between the three-dimensional space regions, is static; When the first information is true, the second information generation unit generates, as the second information, information indicating a range in which the three-dimensional space region may exist. An information processing device according to (1). (3) The first information generating unit generates, as the first information, information indicating whether the positional relationship is static. (2) An information processing device according to the present invention. (4) The first information generating unit generates, as the first information, information indicating whether the positional relationship and the correspondence relationship between the three-dimensional space region and information for obtaining tiles of the point cloud are static. (2) An information processing device according to the present invention. (5) The second information generating unit generates, as the second information, information about the three-dimensional space region, including a static correspondence between the three-dimensional space region and information for obtaining tiles of the point cloud. (2) An information processing device according to the present invention. (6) The information for obtaining the tile is the identification information of the tile. (5) An information processing device according to (5). (7) The information for obtaining the tile is identification information of a track in the file that stores the data of the tile. (5) An information processing device according to (5). (8) The first information generating unit generates, as the first information, information indicating whether the relationship, including a positional relationship in three-dimensional space between the three-dimensional space regions, is static; When the first information is true, the second information generation unit generates, as the second information, information indicating the three-dimensional space region in which the reference point position of the three-dimensional space region is static. An information processing device according to (1). (9) The first information generating unit generates, as the first information, information indicating whether the relationship, including a positional relationship in three-dimensional space between the three-dimensional space regions, is static; When the first information is true, the second information generation unit generates, as the second information, information indicating the three-dimensional space region in which the center position of the three-dimensional space region is static. An information processing device according to (1). (10) The first information generation unit generates, as the first information, information indicating whether the relationship, including a correspondence relationship between the three-dimensional space region and information for obtaining tiles of the point cloud, is static; When the first information is true, the second information generation unit generates information about the dynamic three-dimensional space region as the second information without including information indicating the correspondence. An information processing device according to (1). (11) The first information generating unit generates, as the first information, information indicating whether the correspondence is static. (10) An information processing device according to (10). (12) The first information generating unit generates, as the first information, information indicating a positional relationship in a three-dimensional space between the three-dimensional space regions and whether the correspondence relationship is static. (10) An information processing device according to (10). (13) The second information generating unit generates information about the dynamic three-dimensional space regions, the information further including information indicating the number of the static three-dimensional space regions. (10) An information processing device according to (10). (14) The information for obtaining the tile is identification information of the tile. (10) An information processing device according to (10). (15) The information for obtaining the tile is identification information of a track in the file that stores the data of the tile. (10) An information processing device according to (10). (16) The file generation unit generates a control file that controls playback of the file, and stores the first information in the control file. An information processing device according to (1). (17) generating first information regarding changes in relationships for independently decodable three-dimensional spatial regions of a point cloud representing a three-dimensional shaped object; generating second information about the three-dimensional space region in response to the first information; generating a file storing a bitstream of encoded data in which the point cloud is encoded, the first information, and the second information; Information processing methods.

[0314] (21) An extraction unit that refers to first information about changes in a relationship between independently decodable three-dimensional spatial regions of the point cloud, the first information being stored in a file that stores a bit stream of encoded data in which a point cloud representing a three-dimensional object is encoded, and extracts data of tiles that constitute the three-dimensional spatial region that constructs the point cloud based on second information about the three-dimensional spatial region generated in accordance with the first information when the relationship is static; a decoding unit that decodes the extracted data; An information processing device comprising: (22) The first information is information indicating whether the relationship, including the positional relationship in three-dimensional space between the three-dimensional space regions, is static; the second information is static information indicating a range in which the three-dimensional space region may exist, The extraction unit identifies the three-dimensional space region for constructing the point cloud based on static information indicating a range in which the three-dimensional space region may exist. (21) An information processing device according to (21). (23) The first information is information indicating whether the positional relationship is static. (22) An information processing device according to (22). (24) The first information is information indicating whether the positional relationship and the correspondence relationship between the three-dimensional space area and the information for obtaining the tile are static. (22) An information processing device according to (22). (25) The second information further includes static information about the three-dimensional space region, the static information including a correspondence between the three-dimensional space region and information for obtaining the tiles; The extraction unit extracts, from the file, data of the tiles that constitute the three-dimensional spatial area identified based on static information that indicates a range in which the three-dimensional spatial area may exist, based on information about the three-dimensional spatial area. (22) An information processing device according to (22). (26) The information for obtaining the tile is identification information of the tile. (25) An information processing device according to (25). (27) The information for obtaining the tile is identification information of a track in the file that stores the data of the tile. (25) An information processing device according to (25). (28) The first information is information indicating whether the relationship, including the positional relationship in three-dimensional space between the three-dimensional space regions, is static; the second information is information indicating the three-dimensional space region in which a reference point position of the three-dimensional space region is static, The extraction unit identifies the three-dimensional space region for constructing the point cloud based on information indicating the three-dimensional space region. (21) An information processing device according to (21). (29) The first information is information indicating whether the relationship, including the positional relationship in three-dimensional space between the three-dimensional space regions, is static; the second information is information indicating a three-dimensional space region whose center position is static, The extraction unit identifies the three-dimensional space region for constructing the point cloud based on information indicating the three-dimensional space region. (21) An information processing device according to (21). (30) The first information is information indicating whether the relationship, including the correspondence relationship between the three-dimensional space area and the information for obtaining the tile, is static; the second information is information about the dynamic three-dimensional space region that does not include information indicating the correspondence relationship; The extraction unit extracts the tile data from the file based on dynamic information about the three-dimensional space region and static information indicating the correspondence relationship. (21) An information processing device according to (21). (31) The first information is information indicating whether the correspondence is static. (30) An information processing device according to (30). (32) The first information is information indicating a positional relationship between the three-dimensional space regions in a three-dimensional space and whether the correspondence is static. (30) An information processing device according to (30). (33) The second information is information about the dynamic three-dimensional space regions, further including information indicating the number of the static three-dimensional space regions; The extraction unit extracts the tile data from the file based on dynamic information about the three-dimensional space region and static information indicating the correspondence relationship. (30) An information processing device according to (30). (34) The information for obtaining the tile is identification information of the tile. (30) An information processing device according to (30). (35) The information for obtaining the tile is identification information of a track in the file that stores the data of the tile. (30) An information processing device according to (30). (36) The extraction unit refers to the first information stored in a control file that controls playback of the file, and, if the relationship is static, extracts the data of the tile from the file based on the second information stored in the file. (21) An information processing device according to (21). (37) Referring to first information regarding changes in the relationship of independently decodable three-dimensional spatial regions of the point cloud, which is stored in a file storing a bit stream of encoded data in which a point cloud representing a three-dimensional object is encoded, and if the relationship is static, extracting data of tiles constituting the three-dimensional spatial region that constructs the point cloud based on second information regarding the three-dimensional spatial region generated in accordance with the first information; Decrypting the extracted data Information processing methods. [Explanation of symbols]

[0315] 300 file generation device, 311 extraction unit, 312 encoding unit, 313 bitstream generation unit, 314 first information generation unit, 315 second information generation unit, 316 file generation unit, 321 geometry encoding unit, 322 attribute encoding unit, 323 metadata generation unit, 400 playback device, 401 control unit, 411 file acquisition unit, 412 playback processing unit, 413 presentation processing unit, 421 file processing unit, 422 decoding unit, 423 presentation information generation unit, 431 bitstream extraction unit, 441 geometry decoding unit, 442 attribute decoding unit, 451 point cloud construction unit, 452 presentation processing unit

Claims

1. a first information generating unit that generates first information indicating whether a spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud that represents an object of a three-dimensional shape and a correspondence relationship between identification information of a track that stores tile data of the point cloud and the three-dimensional spatial region are static; a second information generating unit that generates second information regarding the dynamic three-dimensional space region without including information indicating the correspondence relationship when the first information is true; a file generation unit that generates a file that stores a bit stream of encoded data obtained by encoding the point cloud, the first information, and the second information; An information processing device comprising:

2. The second information generation unit generates the second information including information indicating the correspondence when the first information is false. The information processing device according to claim 1 .

3. When the first information is true, the second information generation unit further generates the second information without including information indicating the number of dynamic three-dimensional spatial regions. The information processing device according to claim 1 .

4. The second information generation unit generates the second information including information indicating the number of the static three-dimensional space regions when the first information is true. The information processing device according to claim 3 .

5. When the first information is false, the second information generation unit generates the second information including information indicating the number of dynamic three-dimensional spatial regions. The information processing device according to claim 3 .

6. generating first information indicating whether a spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and a correspondence relationship between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region are static; If the first information is true, generating second information regarding the dynamic three-dimensional space region without including information indicating the correspondence; generating a file storing a bitstream of encoded data in which the point cloud is encoded, the first information, and the second information; Information processing methods.

7. an extraction unit that, when first information indicating whether a spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and a correspondence relationship between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region is static, extracts data of the tile based on information indicating the correspondence, which is not included in second information regarding the dynamic three-dimensional spatial region; a decoding unit that decodes the extracted data; An information processing device comprising:

8. When the first information is false, the extraction unit extracts the data of the tile based on information indicating the correspondence included in the second information. The information processing device according to claim 7 .

9. When the first information is true, the extraction unit further extracts data of the tile based on information indicating the number of static three-dimensional spatial regions included in the second information. The information processing device according to claim 7 .

10. When the first information is false, the extraction unit further extracts data of the tile based on information indicating the number of dynamic three-dimensional spatial regions included in the second information. The information processing device according to claim 7 .

11. extracting data of the tile based on information indicating the correspondence between the three-dimensional spatial regions and the track identification information storing the tile data of the point cloud, which is dynamic, when first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of the point cloud and the correspondence between the three-dimensional spatial regions and the track identification information storing the tile data of the point cloud is true; Decrypting the extracted data Information processing methods.

12. A first information generating unit that generates first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of three-dimensional shape, and the correspondence between identification information of a track that stores tile data of the point cloud and the three-dimensional spatial region is static; a second information generating unit configured to generate second information indicating the three-dimensional space region in which a predetermined position in the three-dimensional space region is static when the first information is true; a file generation unit that generates a file that stores a bit stream of encoded data obtained by encoding the point cloud, the first information, and the second information; An information processing device comprising:

13. The predetermined position is a static reference position of the three-dimensional space region included in the second information. The information processing device according to claim 12.

14. The predetermined position is the center position of the three-dimensional space region. The information processing device according to claim 12.

15. The second information generation unit generates the second information including the size of the three-dimensional space region when the first information is true. The information processing device according to claim 12.

16. Generate first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing a three-dimensional object, and the correspondence between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region are static; If the first information is true, generating second information indicating the three-dimensional space region in which a predetermined position in the three-dimensional space region is static; generating a file storing a bitstream of encoded data in which the point cloud is encoded, the first information, and the second information; Information processing methods.

17. An extraction unit that extracts data of the tiles based on second information indicating a three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static when first information indicating a spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and a correspondence between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region is true; a decoding unit that decodes the extracted data; An information processing device comprising:

18. The predetermined position is a static reference position of the three-dimensional space region included in the second information. The information processing device according to claim 17.

19. The predetermined position is the center position of the three-dimensional space region. The information processing device according to claim 17.

20. When first information indicating whether the spatial positional relationship between independently decodable three-dimensional spatial regions of a point cloud representing an object of a three-dimensional shape and the correspondence between identification information of a track storing tile data of the point cloud and the three-dimensional spatial region is static is true, extracting data of the tile based on second information indicating the three-dimensional spatial region in which a predetermined position of the three-dimensional spatial region is static; Decrypting the extracted data Information processing methods.

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