# US 11,909,992 B2 · Three-dimensional data encoding method, three-dimensional data decoding method, three-dimensional data encoding device, and three-dimensional data decoding device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,909,992 B2 - Document ID: US11909992B2 - Status: Granted - Kind: B2 - Application number: 17/390,194 - Filed: 2021-07-30 - Published: 2021-11-25 - Granted: 2024-02-20 - Earliest claimed: 2019-02-05 - Assignees: Panasonic Intellectual Property Corporation of America - Applicants: Panasonic Intellectual Property Corporation of America - Inventors: Toshiyasu Sugio; Noritaka Iguchi; Chung Dean Han; Chi Wang; Pongsak Lasang - Web page: https://patentgrep.com/patent/US11909992B2 ## CPC - H04N 19/30: using hierarchical techniques, e.g. scalability (H04N19/63 takes precedence) - G06T 9/001: {Model-based coding, e.g. wire frame} - G06T 9/40: Tree coding, e.g. quadtree, octree - H04N 19/124: Quantisation - H04N 19/46: Embedding additional information in the video signal during the compression process (H04N19/517, H04N19/68, H04N19/70 take precedence) - H04N 19/597: specially adapted for multi-view video sequence encoding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract A three-dimensional data encoding method includes: calculating coefficient values from pieces of attribute information of three-dimensional points included in point cloud data; quantizing the coefficient values individually to generate quantized values; and generating a bitstream including the quantized values. Each of the coefficient values belongs to any one of layers. In the quantizing, each of the coefficient values is quantized using a quantization parameter for a layer to which the coefficient value belongs among the layers, and the bitstream includes first information and pieces of second information, the first information indicating a reference quantization parameter, the pieces of second information being for calculating quantization parameters for the layers from the reference quantization parameter. ## Claims ### Claim 1 A three-dimensional data encoding method, comprising: calculating coefficient values from pieces of attribute information of three-dimensional points included in point cloud data; quantizing the coefficient values individually to generate quantized values; and generating a bitstream including the quantized values, wherein each of the coefficient values belongs to any one of layers, in the quantizing, each of the coefficient values is quantized using a quantization parameter for a corresponding layer to which the coefficient value belongs among the layers, the three-dimensional data encoding method further comprises calculating the quantization parameter for each of the layers, and the bitstream includes pieces of first information, the pieces of first information being for the calculating of the quantization parameter for each of the layers. ### Claim 2 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein each of the pieces of first information indicates a difference between a reference quantization parameter and a quantization parameter for a corresponding one of the layers among the quantization parameters. ### Claim 3 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein the bitstream further includes a first flag indicating whether or not the pieces of first information are included in the bitstream. ### Claim 4 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein the bitstream further includes third information indicating a total number of the pieces of first information included in the bitstream. ### Claim 5 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein each of the three-dimensional points is classified into any one of the layers in accordance with geometry information of the three-dimensional point. ### Claim 6 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein the coefficient values are generated by sorting each of the pieces of attribute information to one of a higher frequency component and a lower frequency component to be classified into the layers. ### Claim 7 A three-dimensional data decoding method, comprising: calculating a quantization parameter for each of a plurality of layers using pieces of first information, the pieces of first information being included in a bitstream; inverse-quantizing each of quantized values included in the bitstream, using a quantization parameter for a corresponding layer of the plurality of layers to which the quantized value belongs among the quantization parameters calculated in the calculating, to generate coefficient values; and calculating, from the coefficient values generated in the inverse-quantizing, pieces of attribute information of three-dimensional points included in point cloud data. ### Claim 8 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein each of the pieces of first information indicates a difference between a reference quantization parameter and a quantization parameter for a corresponding one of the layers among the quantization parameters. ### Claim 9 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein the bitstream further includes a first flag indicating whether or not the pieces of first information are included in the bitstream. ### Claim 10 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein the bitstream further includes third information indicating a total number of the pieces of first information included in the bitstream. ### Claim 11 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein each of the three-dimensional points is classified into any one of the layers in accordance with geometry information of the three-dimensional point. ### Claim 12 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein the coefficient values are generated by sorting each of the pieces of attribute information to one of a higher frequency component and a lower frequency component to be classified into the layers. ### Claim 13 A three-dimensional data encoding device, comprising: a processor; and memory, wherein using the memory, the processor: calculates coefficient values from pieces of attribute information of three-dimensional points included in point cloud data; quantizes the coefficient values individually to generate quantized values; and generates a bitstream including the quantized values, wherein each of the coefficient values belongs to any one of layers, in the quantizing, each of the coefficient values is quantized using a quantization parameter for a corresponding layer to which the coefficient value belongs among the layers, the three-dimensional data encoding method further comprises calculating the quantization parameter for each of the layers, and the bitstream includes pieces of first information, the pieces of first information being for the calculating of the quantization parameter for each of the layers. ### Claim 14 A three-dimensional data decoding device, comprising: a processor; and memory, wherein using the memory, the processor: calculates a quantization parameter for each of a plurality of layers using pieces of first information, the pieces of first information being included in a bitstream; inverse-quantizes each of quantized values included in the bitstream, using a quantization parameter for a corresponding layer of the plurality of layers to which the quantized value belongs among the quantization parameters calculated in the calculating, to generate coefficient values; and calculates, from the coefficient values generated in the inverse-quantizing, pieces of attribute information of three-dimensional points included in point cloud data. ### Claim 15 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein each of the layers is a Level of Detail (LoD) layer or a Region Adaptive Hierarchical Transform (RAHT) layer. ### Claim 16 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein the bitstream further includes second information, the second information indicating a reference quantization parameter, and the quantization parameters for the layers are calculated from the reference quantization parameter. ### Claim 17 (depends on 1) The three-dimensional data encoding method according to claim 1, wherein a total number of the pieces of first information included in the bitstream is equal to a total number of the layers. ### Claim 18 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein each of the layers is a Level of Detail (LoD) layer or a Region Adaptive Hierarchical Transform (RAHT) layer. ### Claim 19 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein the bitstream further includes second information, the second information indicating a reference quantization parameter, and the quantization parameters for the layers are calculated from the reference quantization parameter. ### Claim 20 (depends on 7) The three-dimensional data decoding method according to claim 7, wherein a total number of the pieces of first information included in the bitstream is equal to a total number of the layers.