Three-dimensional data encoding method, three-dimensional data decoding method, three-dimensional data encoding device, and three-dimensional data decoding device

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.

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.

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.