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

Abstract

A three-dimensional data encoding method includes: calculating a prediction residual that is a difference between geometry information of a three-dimensional point included in point cloud data and a predicted value; quantizing the prediction residual using a first quantization parameter; and generating a bitstream including (i) first information indicating the prediction residual quantized, (ii) second information indicating a second quantization parameter, (iii) third information indicating a first difference between the second quantization parameter and the first quantization parameter, (iv) fourth information indicating a first bit count of the first information, and (v) fifth information indicating a second bit count of the fourth information. When the first difference is not zero, the bitstream further includes sixth information indicating an amount of change in the fifth information that is in accordance with the first difference, and when the first difference is zero, the bitstream does not include the sixth information.