Method and apparatus for point cloud coding
Aspects of the disclosure provide methods, apparatuses, and a non-transitory computer-readable medium for point cloud compression and decompression. In some examples, an apparatus for point cloud compression/decompression includes processing circuitry. The processing circuitry determines, for each point in a first point cloud, a corresponding point in a second point cloud. The first point cloud is a processed point cloud based on the second point cloud. The processing circuitry determines, for each point in the first point cloud, a corresponding error vector based on the corresponding point in the second point cloud. The processing circuitry determines, for each point in the first point cloud, a corresponding weight factor based on a position of the respective point in the first point cloud. The processing circuitry determines a quality metric for the first point cloud based on the error vectors and the weight factors.
1. A method for point cloud coding in a decoder, comprising:
for each of a plurality of points in a first point cloud,
determining a corresponding point in a second point cloud, the first point cloud being a processed point cloud based on the second point cloud;
determining a corresponding error vector based on the corresponding point in the second point cloud;
determining whether a distance of the respective point in the first point cloud from a same reference point is within a predefined distance subrange; and
in response to a determination that the distance of the respective point in the first point cloud is within the predefined distance subrange, determining a corresponding weight factor of the respective point in the first point cloud as a non-zero number; and
determining a quality metric for the first point cloud based on squared lengths of the error vectors multiplied by the weight factors.
2. The method of claim 1 , wherein the determining the corresponding weight factor comprises:
determining the corresponding weight factor of the respective point based on a velocity vector and a position of the respective point in the first point cloud.
3. The method of claim 1 , further comprising:
for each of the plurality of points in the first point cloud,
in response to a determination that the distance of the respective point in the first point cloud is not within the predefined distance subrange, determining the corresponding weight factor of the respective point in the first point cloud as zero.
4. The method of claim 1 , wherein the determining the corresponding weight factor comprises:
determining the corresponding weight factor of the respective point in the first point cloud as a positive constant.
5. The method of claim 1 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are inversely related to the norm values of the positions of the subset of the points in the first point cloud.
6. The method of claim 1 , wherein
both the first point cloud and the second point cloud use a same coordinate system, and
the determining the corresponding point in the second point cloud includes determining for each point in the first point cloud, the corresponding point in the second point cloud to be a point in the second point cloud that is nearest to the respective point in the first point cloud.
7. The method of claim 2 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are positively related to a norm value of the velocity vector.
8. The method of claim 2 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are determined based on a comparison between a norm value of the velocity vector and a third threshold.
9. The method of claim 2 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are positively related to a norm value of the velocity vector in one direction.
10. The method of claim 2 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are determined based on a comparison between a norm value of the velocity vector in one direction and a fourth threshold.
11. An apparatus for point cloud coding, comprising processing circuitry configured to:
for each of a plurality of points in a first point cloud,
determine a corresponding point in a second point cloud, the first point cloud being a processed point cloud based on the second point cloud;
determine a corresponding error vector based on the corresponding point in the second point cloud;
determine whether a distance of the respective point in the first point cloud from a same reference point is within a predefined distance subrange; and
in response to a determination that the distance of the respective point in the first point cloud is within the predefined distance subrange, determine a corresponding weight factor of the respective point in the first point cloud as a non-zero number; and
determine a quality metric for the first point cloud based on squared lengths of the error vectors multiplied by the weight factors.
12. The apparatus of claim 11 , wherein the processing circuitry is configured to:
in response to the determination that the distance of the respective point is within the predefined distance subrange,
determine the corresponding weight factor based on a velocity vector and a position of the respective point in the first point cloud.
13. The apparatus of claim 11 , wherein the processing circuitry is configured to:
for each of the plurality of points in the first point cloud,
in response to a determination that the distance of the respective point in the first point cloud is not within the predefined distance subrange, determine the corresponding weight factor of the respective point in the first point cloud as zero.
14. The apparatus of claim 11 , wherein the processing circuitry is configured to:
in response to the determination that the distance of the respective point is within the predefined distance subrange, determine the corresponding weight factor of the respective point in the first point cloud as a positive constant.
15. The apparatus of claim 11 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are inversely related to the norm values of the positions of the subset of the points in the first point cloud.
16. The apparatus of claim 12 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are positively related to a norm value of the velocity vector.
17. The apparatus of claim 12 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are determined based on a comparison between a norm value of the velocity vector and a third threshold.
18. The apparatus of claim 12 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are positively related to a norm value of the velocity vector in one direction.
19. The apparatus of claim 12 , wherein
norm values of positions of a subset of the points in the first point cloud are (i) equal to or greater than a first threshold and (ii) equal to or less than a second threshold, and
the corresponding weight factors of the subset of the points in the first point cloud are determined based on a comparison between a norm value of the velocity vector in one direction and a fourth threshold.
20. A non-transitory computer-readable medium storing instructions which when executed by a computer for point cloud coding cause the computer to perform:
for each of a plurality of points in a first point cloud,
determining a corresponding point in a second point cloud, the first point cloud being a processed point cloud based on the second point cloud;
determining a corresponding error vector based on the corresponding point in the second point cloud;
determining whether a distance of the respective point in the first point cloud from a same reference point is within a predefined range distance subrange; and
in response to a determination that the distance of the respective point in the first point cloud is within the predefined distance subrange, determining a corresponding weight factor of the respective point in the first point cloud as a non-zero number; and
determining a quality metric for the first point cloud based on squared lengths of the error vectors multiplied by the weight factors.