# US 12,003,749 B2 · Mapping intra prediction modes to wide angle modes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,749 B2 - Document ID: US12003749B2 - Status: Granted - Kind: B2 - Application number: 17/946,777 - Filed: 2022-09-16 - Published: 2023-01-26 - Granted: 2024-06-04 - Earliest claimed: 2018-07-02 - Assignees: Tencent America LLC - Applicants: Tencent America LLC - Inventors: Liang Zhao; Shan Liu; Xin Zhao; Xiang Li - Web page: https://patentgrep.com/patent/US12003749B2 ## CPC - H04N 19/44: Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder - H04N 19/103: Selection of coding mode or of prediction mode - H04N 19/11: among a plurality of spatial predictive coding modes - H04N 19/119: Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks - H04N 19/159: Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/593: involving spatial prediction techniques - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A method for video encoding includes selecting a second intra prediction mode for encoding a first block, the first block being a non-square block and the second intra prediction mode being selected from a second set of intra prediction modes. The method also includes generating prediction information for the first block, the generated prediction information indicating a first intra prediction mode in a first set of intra prediction modes. The second set of intra prediction modes includes at least the selected second intra prediction mode, which is not included in the first set of intra prediction modes and is outside an angular range of the first set of intra prediction modes that extends 180 degrees from a bottom-left diagonal direction mode to a top-right diagonal direction mode. The method also includes encoding at least one sample of the first block according to the second intra prediction mode. ## Claims ### Claim 1 A method for video encoding in an encoder, comprising: selecting a second intra prediction mode for encoding a first block to be included in a coded video bitstream, the first block being a non-square block and the second intra prediction mode being selected from a second set of intra prediction modes for the non-square block; generating prediction information for the first block, the generated prediction information indicating a first intra prediction mode in a first set of intra prediction modes for a square block, the second set of intra prediction modes including at least the selected second intra prediction mode, which is not included in the first set of intra prediction modes and is outside an angular range of the first set of intra prediction modes that extends 180 degrees from a bottom-left diagonal direction mode to a top-right diagonal direction mode, the generated prediction information being included in the coded video bitstream; and encoding at least one sample of the first block according to the second intra prediction mode. ### Claim 2 (depends on 1) The method of claim 1, further comprising: determining an intra prediction angle parameter associated with the second intra prediction mode; and encoding the at least one sample of the first block according to the intra prediction angle parameter. ### Claim 3 (depends on 1) The method of claim 1, wherein the first intra prediction mode is a disabled intra prediction mode for the non-square block. ### Claim 4 (depends on 1) The method of claim 1, further comprising: determining the second set of intra prediction modes based on a shape of the first block. ### Claim 5 (depends on 1) The method of claim 1, further comprising: calculating an aspect ratio of the first block; and determining, based on the aspect ratio of the first block, a subset of disabled intra prediction modes for the non-square block. ### Claim 6 (depends on 5) The method of claim 5, wherein the subset of disabled intra prediction modes has a first number of disabled intra prediction modes when a ratio of a longer side to a shorter side of the first block is less than or equal to 2, and has a second number of disabled intra prediction modes when the ratio is greater than or equal to 4, and the second number is larger than the first number. ### Claim 7 (depends on 1) The method of claim 1, further comprising: determining that a width of the first block is larger than a height of the first block; and detecting that the first intra prediction mode is within a subset of disabled intra prediction modes that starts from the bottom-left diagonal direction mode in the first set of intra prediction modes. ### Claim 8 (depends on 1) The method of claim 1, further comprising: determining that a height of the first block is larger than a width of the first block; and detecting that the first intra prediction mode is within a subset of disabled intra prediction modes that starts from the top-right diagonal direction mode in the first set of intra prediction modes. ### Claim 9 (depends on 1) The method of claim 1, further comprising: determining that a width of the first block is greater than a height of the first block; and subtracting a value from a mode number associated with the second intra prediction mode to determine the first intra prediction mode based on the second intra prediction mode. ### Claim 10 (depends on 1) The method of claim 1, further comprising: determining that a height of the first block is greater than a width of the first block; and adding a value to a mode number associated with the second intra prediction mode to convert the second intra prediction mode to the first intra prediction mode. ### Claim 11 An apparatus, comprising: processing circuitry configured to: select a second intra prediction mode for encoding a first block to be included in a coded video bitstream, the first block being a non-square block and the second intra prediction mode being selected from a second set of intra prediction modes for the non-square block; generate prediction information for the first block, the generated prediction information indicating a first intra prediction mode in a first set of intra prediction modes for a square block, the second set of intra prediction modes including at least the selected second intra prediction mode, which is not included in the first set of intra prediction modes and is outside an angular range of the first set of intra prediction modes that extends 180 degrees from a bottom-left diagonal direction mode to a top-right diagonal direction mode, the generated prediction information being included in the coded video bitstream; and encode at least one sample of the first block according to the second intra prediction mode. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the processing circuitry is configured to: determine an intra prediction angle parameter associated with the second intra prediction mode; and encode the at least one sample of the first block according to the intra prediction angle parameter. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the first intra prediction mode is a disabled intra prediction mode for the non-square block. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the processing circuitry is configured to: determine the second set of intra prediction modes based on a shape of the first block. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the processing circuitry is configured to: calculate an aspect ratio of the first block; and determine, based on the aspect ratio of the first block, a subset of disabled intra prediction modes for the non-square block. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the subset of disabled intra prediction modes has a first number of disabled intra prediction modes when a ratio of a longer side to a shorter side of the first block is less than or equal to 2, and has a second number of disabled intra prediction modes when the ratio is greater than or equal to 4, and the second number is larger than the first number. ### Claim 17 (depends on 11) The apparatus of claim 11, wherein the processing circuitry is configured to: determine that a width of the first block is larger than a height of the first block; and detect that the first intra prediction mode is within a subset of disabled intra prediction modes that starts from the bottom-left diagonal direction mode in the first set of intra prediction modes. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein the processing circuitry is configured to: determine that a height of the first block is larger than a width of the first block; and detect that the first intra prediction mode is within a subset of disabled intra prediction modes that starts from the top-right diagonal direction mode in the first set of intra prediction modes. ### Claim 19 (depends on 11) The apparatus of claim 11, wherein the processing circuitry is configured to: when a width of the first block is greater than a height of the first block, subtract a value from a mode number associated with the second intra prediction mode to determine the first intra prediction mode based on the second intra prediction mode; and when the height of the first block is greater than the width of the first block, add a value to the mode number associated with the second intra prediction mode to convert the second intra prediction mode to the first intra prediction mode. ### Claim 20 A non-transitory computer-readable medium storing instructions which, when executed by a computer for video encoding, cause the computer to perform: selecting a second intra prediction mode for encoding a first block to be included in a coded video bitstream, the first block being a non-square block and the second intra prediction mode being selected from a second set of intra prediction modes for the non-square block; generating prediction information for the first block, the generated prediction information indicating a first intra prediction mode in a first set of intra prediction modes for a square block, the second set of intra prediction modes including at least the selected second intra prediction mode, which is not included in the first set of intra prediction modes and is outside an angular range of the first set of intra prediction modes that extends 180 degrees from a bottom-left diagonal direction mode to a top-right diagonal direction mode, the generated prediction information being included in the coded video bitstream; and encoding at least one sample of the first block according to the second intra prediction mode.