# US 11,451,802 B2 · Method and apparatus for point cloud coding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,451,802 B2 - Document ID: US11451802B2 - Status: Granted - Kind: B2 - Application number: 17/211,536 - Filed: 2021-03-24 - Published: 2021-10-21 - Granted: 2022-09-20 - Earliest claimed: 2020-04-17 - Assignees: Tencent America LLC - Applicants: Tencent America LLC - Inventors: Sehoon Yea; Wen Gao; Shan Liu - Web page: https://patentgrep.com/patent/US11451802B2 ## CPC - H04N 19/103: Selection of coding mode or of prediction mode - H04N 19/186: the unit being a colour or a chrominance component - H04N 19/136: Incoming video signal characteristics or properties - H04N 19/172: the region being a picture, frame or field - H04N 19/174: the region being a slice, e.g. a line of blocks or a group of blocks - H04N 19/184: the unit being bits, e.g. of the compressed video stream - H04N 19/44: Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract In a method of point cloud geometry decoding in a point cloud decoder, chroma prediction residual information of a point in a set of points is received from a coded bitstream for a point cloud that includes the set of points. The chroma prediction residual information includes a Cb component and a Cr component. Further, a type of correlation between the Cb component and the Cr component of the chroma prediction residual information is determined by processing circuitry and from the coded bitstream for the point cloud. The chroma prediction residual information is decoded based on the type of the correlation between the Cb component and the Cr component of the chroma prediction residual information. ## Claims ### Claim 1 A method of point cloud geometry decoding in a point cloud decoder, comprising: receiving, from a coded bitstream for a point cloud that includes a set of points, chroma prediction residual information of a point in the set of points, the chroma prediction residual information including a Cb component and a Cr component; determining, by processing circuitry and from the coded bitstream for the point cloud, a type of correlation from among a plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information; and decoding the chroma prediction residual information based on the determined type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information. ### Claim 2 (depends on 1) The method of claim 1, wherein the decoding comprises: decoding the Cb component of the chroma prediction residual information and the Cb component minus the Cr component of the chroma prediction residual information based on the determined type of the correlation from among the plurality of correlation types between the Cb component and the Cr component being positive. ### Claim 3 (depends on 1) The method of claim 1, wherein the decoding comprises: decoding the Cb component of the chroma prediction residual information and the Cb component plus the Cr component of the chroma prediction residual information based on the determined type of the correlation from among the plurality of correlation types between the Cb component and the Cr component being negative. ### Claim 4 (depends on 1) The method of claim 1, wherein the decoding comprises: decoding the Cb component of the chroma prediction residual information and the Cr component of the chroma prediction residual information based on no indicated correlation between the Cb component and the Cr component. ### Claim 5 (depends on 1) The method of claim 1, wherein the determining comprises: determining the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is positive based on a first number of residual points from one of a coded region, a previous level of detail (LOD), or N nearest-neighboring points of the point being positively correlated; and determining the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is negative based on a second number of residual points from the one of the coded region, the previous LOD, or the N nearest-neighboring points of the point being negatively correlated. ### Claim 6 (depends on 5) The method of claim 5, wherein the coded region comprises at least one of a frame, a video sequence, a group of pictures (GOP), a picture, a slice, or a tile. ### Claim 7 (depends on 5) The method of claim 5, wherein the N is a positive integer that is equal to 3 or 4. ### Claim 8 (depends on 1) The method of claim 1, wherein the coded bitstream includes signaling information that is indicative of the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information, the signaling information indicating the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is positive based on a first number of residual points from one of a coded region, a previous level of detail (LOD), a LOD to which the point belongs, and N nearest-neighboring points of the point being positively correlated, and the signaling information indicating the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is negative based on a second number of residual points from the one of the coded region, the previous LOD. the LOD to which the point belongs, and the N nearest-neighboring points of the point being negatively correlated. ### Claim 9 A method of point cloud geometry decoding in a point cloud decoder, comprising: receiving, from a coded bitstream for a point cloud that includes a set of points, first signaling information that indicates first chroma prediction residual information and second chroma prediction residual information of a point in the set of points is decoded based on a type of correlation from among a plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information, the coded bitstream including the first chroma prediction residual information and the second chroma prediction residual information; determining the type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information based on the first signaling information; and reconstructing first chroma information and second chroma information based on the first chroma prediction residual information, the second chroma prediction residual information, and the determined type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information. ### Claim 10 (depends on 9) The method of claim 9, wherein the determining further comprises: determining second signaling information based on the first signaling information being a first value, the second signaling information indicating that the type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information is indicated by third signaling information; determining the third signaling information based on the second signaling information being the first value, the third signaling information indicating the type of the correlation from among the plurality of correlation types between the first chroma prediction residual nation and the second chroma prediction residual information; and determining the type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information based on the third signaling information. ### Claim 11 (depends on 10) The method of claim 10, wherein the determining the type of the correlation further comprises: determining the type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information is negative based on the third signaling information being the first value; and determining the type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information is positive based on the third signaling information being a second value. ### Claim 12 (depends on 9) The method of claim 9, wherein the reconstructing further comprises: reconstructing the first chroma information by performing a first inverse-quantization process on the first chroma prediction residual information; and in response to the first signaling information being a first value, reconstructing the second chroma information that includes a first portion and a second portion, wherein: the first portion is obtained by performing a second inverse-quantization process on the second chroma prediction residual information, and the second portion is obtained by multiplying the reconstructed first chroma information and the type of the correlation from among the plurality of correlation types between the first chroma prediction residual information and the second chroma prediction residual information. ### Claim 13 (depends on 9) The method of claim 9, wherein the reconstructing further comprises: reconstructing the first chroma information by performing a first inverse-quantization process on the first chroma prediction residual information; and in response to the first signaling information being a second value, reconstructing the second chroma information by performing a second inverse-quantization process on the second chroma prediction residual information. ### Claim 14 (depends on 8) The method of claim 8, wherein the first chroma prediction residual information and the second chroma prediction residual information are correlated in a first order relation with zero offsets. ### Claim 15 An apparatus of processing point cloud data, comprising: processing circuitry configured to: receive, from a coded bitstream for a point cloud that includes a set of points, chroma prediction residual information of a point in the set of points, the chroma prediction residual information including a Cb component and a Cr component; determine, from the coded bitstream for the point cloud, a type of correlation from among a plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information; and decode the chroma prediction residual information based on the determined type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the processing circuitry is further configured to: decode the Cb component of the chroma prediction residual information and the Cb component minus the Cr component of the chroma prediction residual information based on the determined type of the correlation from among the plurality of correlation types between the Cb component and the Cr component being positive. ### Claim 17 (depends on 15) The apparatus of claim 15, wherein the processing circuitry is further configured to: decode the Cb component of the chroma prediction residual information and the Cb component plus the Cr component of the chroma prediction residual information based on the determined type of the correlation from among the plurality of correlation types between the Cb component and the Cr component being negative. ### Claim 18 (depends on 15) The apparatus of claim 15, wherein the processing circuitry is further configured to: decode the Cb component of the chroma prediction residual information and the Cr component of the chroma prediction residual information based on no indicated correlation between the Cb component and the Cr component. ### Claim 19 (depends on 15) The apparatus of claim 15, wherein the processing circuitry is further configured to: determined the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is positive based on a first number of residual points from one of a coded region, a previous level of detail (LOD), or N nearest-neighboring points of the point being positively correlated; and determine the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is negative based on a second number of residual points from the one of the coded region, the previous LOD, or the N nearest-neighboring points of the point being negatively correlated. ### Claim 20 (depends on 15) The apparatus of claim 15, wherein the coded bitstream includes signaling information that is indicative of the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information, the signaling information indicating the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is positive based on a first number of residual points from one of a coded region, a previous level of detail (LOD), a LOD to which the point belongs, and N nearest-neighboring points of the point being positively correlated, and the signaling information indicating the type of the correlation from among the plurality of correlation types between the Cb component and the Cr component of the chroma prediction residual information is negative based on a second number of residual points from the one of the coded region, the previous LOD, the LOD to which the point belongs, and the N nearest-neighboring points of the point being negatively correlated.