Trisoup syntax signaling for geometry-based point cloud compression

1. A method of processing point cloud data, the method comprising:

counting a number of edges of a cube of the point cloud data that comprise a respective vertex, wherein counting the number of edges of the cube of the point cloud data that comprise the respective vertex comprises counting a number of respective first syntax elements whose respective values indicate that a respective edge of the cube of the point cloud data includes a respective vertex;

setting a variable based on a total of the counting; and

processing the point cloud data based on the variable.

2. The method of claim 1 , wherein the variable comprises the total of the counting minus 1.

3. The method of claim 1 , wherein each of the respective first syntax elements comprises a segment indicator syntax element and the respective values that indicate that a respective edge of the cube of the point cloud data includes a respective vertex are equal to 1.

4. The method of claim 1 , wherein the variable is count_minus 1.

5. The method of claim 1 , further comprising:

determining a difference based on the variable and a second syntax element; and

processing the point cloud data based on the difference.

6. The method of claim 5 , wherein a value of the second syntax element is indicative of a number of vertices in the cube minus 1 and the difference equals the value of the second syntax element minus the total of the counting minus 1.

7. The method of claim 5 , further comprising coding the difference with an Exponential-Golomb code.

8. A device for processing point cloud data, the device comprising:

a memory configured to store the point cloud data; and

one or more processors implemented in circuitry and coupled to the memory, the one or more processors being configured to:

count a number of edges of a cube of the point cloud data that comprise a respective vertex, wherein as part of counting the number of edges of the cube of the point cloud data that comprise a respective vertex, the one or more processors are configured to count a number of respective first syntax elements whose respective values indicate that a respective edge of the cube of the point cloud data includes a respective vertex;

set a variable based on a total of the counting; and

process the point cloud data based on the variable.

9. The device of claim 8 , wherein the variable comprises the total of the counting minus 1.

10. The device of claim 8 , wherein each of the respective first syntax elements comprises a segment indicator syntax element and the respective values that indicate that a respective edge of the cube of the point cloud data includes a respective vertex are equal to 1.

11. The device of claim 8 , wherein the variable is count_minus 1.

12. The device of claim 8 , wherein the one or more processors are further configured to:

determine a difference based on the variable and a second syntax element; and

process the point cloud data based on the difference.

13. The device of claim 12 , wherein a value of the syntax element is indicative of a number of vertices in the cube minus 1 and the difference equals the value of the second syntax element minus the total of the counting minus 1.

14. The device of claim 12 , further comprising coding the difference with an Exponential-Golomb code.

15. The device of claim 8 , further comprising:

a display configured to display imagery based on the point cloud data.

16. A non-transitory computer-readable medium storing instructions, which, when executed, cause one or more processors to:

count a number of edges of a cube of point cloud data that comprise a respective vertex, wherein as part of counting the number of edges of the cube of the point cloud data that comprise a respective vertex, the instructions cause the one or more processors to count a number of respective first syntax elements whose respective values indicate that a respective edge of the cube of the point cloud data includes a respective vertex;

set a variable based on a total of the counting; and

process point cloud data based on the variable.

17. The non-transitory computer-readable medium of claim 16 , wherein the variable comprises the total of the counting minus 1.

18. A device for processing point cloud data, the device comprising:

means for counting a number of edges of a cube of the point cloud data that comprise a respective vertex, wherein the means for counting the number of edges of the cube of the point cloud data that comprise a respective vertex comprises means for counting a number of respective first syntax elements whose respective values indicate that a respective edge of the cube of the point cloud data includes a respective vertex;

means for setting a variable based on a total of the counting; and

means for processing the point cloud data based on the variable.