Granted Patent B2

US 12,423,876 · App. 18/122,293 · Granted Sep 23, 2025

Inventors: Toshiyasu Sugio (Osaka, JP); Noritaka Iguchi (Osaka, JP)

Assignee: PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA

G06T9/001G06T9/40

Abstract

Claims (54)

1. A three-dimensional data encoding method comprising:

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,

wherein, 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.

2. The three-dimensional data encoding method according to claim 1 ,

wherein the sixth information indicates an absolute value of the amount of change and does not include information indicating a sign of the amount of change.

3. The three-dimensional data encoding method according to claim 2 ,

wherein the sixth information includes seventh information indicating whether the amount of change is zero, and

when the amount of change is not zero, the sixth information includes eighth information indicating a value obtained by subtracting 1 from the absolute value of the amount of change.

4. The three-dimensional data encoding method according to claim 1 ,

wherein the geometry information includes components, and

the bitstream includes the sixth information for each of the components when the first difference is not zero.

5. The three-dimensional data encoding method according to claim 1 , further comprising:

determining the second bit count using the first quantization parameter.

6. The three-dimensional data encoding method according to claim 1 ,

wherein the calculating of the prediction residual includes calculating the predicted value using a prediction tree indicating a reference relation.

7. A three-dimensional data decoding method comprising:

obtaining a bitstream including (i) first information indicating a quantized prediction residual generated by quantizing a prediction residual using a first quantization parameter, the prediction residual being a difference between geometry information of a three-dimensional point included in point cloud data and a predicted value, (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;

calculating the prediction residual by inversely quantizing the quantized prediction residual using the first quantization parameter; and

calculating the geometry information by adding the prediction residual and the predicted value,

wherein, 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.

8. The three-dimensional data decoding method according to claim 7 ,

wherein the sixth information indicates an absolute value of the amount of change and does not include information indicating a sign of the amount of change, and

the three-dimensional data decoding method further comprises:

determining the sign of the amount of change, based on a sign of the first difference.

9. The three-dimensional data decoding method according to claim 8 ,

wherein the sixth information includes seventh information indicating whether the amount of change is zero, and

when the amount of change is not zero, the sixth information includes eighth information indicating a value obtained by subtracting 1 from the absolute value of the amount of change.

10. The three-dimensional data decoding method according to claim 7 ,

wherein the geometry information includes components, and

the bitstream includes the sixth information for each of the components when the first difference is not zero.

11. The three-dimensional data decoding method according to claim 7 ,

wherein the calculating of the geometry information includes calculating the predicted value using a prediction tree indicating a reference relation.

12. A three-dimensional data encoding device comprising:

a processor; and

memory, wherein

using the memory, the processor:

calculates a prediction residual that is a difference between geometry information of a three-dimensional point included in point cloud data and a predicted value;

quantizes the prediction residual using a first quantization parameter; and

generates 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,

wherein, 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.

13. A three-dimensional data decoding device comprising:

a processor; and

memory, wherein

using the memory, the processor:

obtains a bitstream including (i) first information indicating a quantized prediction residual generated by quantizing a prediction residual using a first quantization parameter, the prediction residual being a difference between geometry information of a three-dimensional point included in point cloud data and a predicted value, (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;

calculates the prediction residual by inversely quantizing the quantized prediction residual using the first quantization parameter; and

calculates the geometry information by adding the prediction residual and the predicted value,

wherein, 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.

Assignments (1)

Continuity (3)

References Cited (20)