# US 12,593,038 B2 · Temporal prediction of parameters in non-linear adaptive loop filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,593,038 B2 - Document ID: US12593038B2 - Status: Granted - Kind: B2 - Application number: 18/449,134 - Filed: 2023-08-14 - Published: 2023-11-30 - Granted: 2026-03-31 - Earliest claimed: 2019-04-15 - Assignees: Beijing Bytedance Network Technology Co., Ltd.; Bytedance Inc. - Applicants: Beijing Bytedance Network Technology Co., Ltd.; Bytedance Inc. - Inventors: Li Zhang; Kai Zhang; Hongbin Liu; Yue Wang - Web page: https://patentgrep.com/patent/US12593038B2 ## CPC - H04N 19/117: Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) - H04N 19/119: Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks - H04N 19/132: Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking - H04N 19/174: the region being a slice, e.g. a line of blocks or a group of blocks - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/184: the unit being bits, e.g. of the compressed video stream - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 19/82: involving filtering within a prediction loop - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Devices, systems and methods for temporal prediction of parameters in non-linear adaptive loop filtering are described. In an exemplary aspect, a method for visual media processing includes configuring, for a current video block, one or more parameters of a clipping operation that is part of a non-linear filtering operation; and performing, based on the one or more parameters, a conversion between the current video block and a bitstream representation of the current video block, wherein the one or more parameters is coded in accordance with a rule. ## Claims ### Claim 1 A method of processing video data, comprising: determining, that a non-linear filtering operation is applied for a current video region of a video; determining, for the current video region, one or more parameters of a clipping operation that is part of the non-linear filtering operation; and performing, based on the one or more parameters, a conversion between the current video region and a bitstream of the video, wherein at least one first filtering index is derived, and a first clipping parameter set is derived based on the at least one first filtering index and the one or more parameters, wherein the one or more parameters are coded with a fixed length of N bits, wherein the at least one first filtering index is derived based on multiple sample differences in different directions, wherein the current video region is split into multiple M×M video sub-regions, and the multiple sample differences in different directions are derived for every M×M video sub-region, wherein M is equal to 2 or 4, and wherein the multiple sample differences in different directions are derived based on a 1:P subsampling rate, and wherein P is greater than 1. ### Claim 2 (depends on 1) The method of claim 1, wherein N is 2. ### Claim 3 (depends on 1) The method of claim 1, wherein the one or more parameters include a clipping index syntax element. ### Claim 4 (depends on 3) The method of claim 3, wherein a first filtering coefficient set is derived based on the at least one first filtering index and a coefficient parameter syntax element. ### Claim 5 (depends on 4) The method of claim 4, wherein a value of the clipping index syntax element is determined independently from the first filtering coefficient set, and wherein in a case that values of the first filtering coefficient set are zero, the clipping index syntax element is included in the bitstream. ### Claim 6 (depends on 1) The method of claim 1, wherein the one or more parameters are included as fields in an adaptive parameter set. ### Claim 7 (depends on 5) The method of claim 5, wherein the clipping index syntax element and the coefficient parameter syntax element are present in a same adaptive parameter set. ### Claim 8 (depends on 4) The method of claim 4, wherein the coefficient parameter syntax element includes a coefficient absolute value. ### Claim 9 (depends on 4) The method of claim 4, wherein the coefficient parameter syntax element is coded using Exponential-Golomb model with fixed order. ### Claim 10 (depends on 1) The method of claim 1, wherein the current video region includes a coding tree block or a slice. ### Claim 11 (depends on 1) The method of claim 1, wherein the conversion includes encoding the current video region into the bitstream. ### Claim 12 (depends on 1) The method of claim 1, wherein the conversion includes decoding the current video region from the bitstream. ### Claim 13 An apparatus for processing video data comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to: determine, that a non-linear filtering operation is applied for a current video region of a video; determine, for the current video region, one or more parameters of a clipping operation that is part of the non-linear filtering operation; and perform, based on the one or more parameters, a conversion between the current video region and a bitstream of the video, wherein at least one first filtering index is derived, and a first clipping parameter set is derived based on the at least one first filtering index and the one or more parameters, and wherein the one or more parameters are coded with a fixed length of N bits, wherein the at least one first filtering index is derived based on multiple sample differences in different directions, wherein the current video region is split into multiple M×M video sub-regions, and the multiple sample differences in different directions are derived for every M×M video sub-region, wherein M is equal to 2 or 4, and wherein the multiple sample differences in different directions are derived based on a 1:P subsampling rate, and wherein P is greater than 1. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein N is 2, wherein the one or more parameters include a clipping index syntax element, wherein a first filtering coefficient set is derived based on the at least one first filtering index and a coefficient parameter syntax element, wherein a value of the clipping index syntax element is determined independently from the first filtering coefficient set, wherein in a case that values of the first filtering coefficient set are zero, the clipping index syntax element is included in the bitstream, wherein the one or more parameters are included as fields in an adaptive parameter set, wherein the clipping index syntax element and the coefficient parameter syntax element are present in a same adaptive parameter set, wherein the coefficient parameter syntax element includes a coefficient absolute value, wherein the coefficient parameter syntax element is coded using Exponential-Golomb model with fixed order, and wherein the current video region includes a coding tree block or a slice. ### Claim 15 A non-transitory computer-readable storage medium storing instructions that cause a processor to: determine, that a non-linear filtering operation is applied for a current video region of a video; determine, for the current video region, one or more parameters of a clipping operation that is part of the non-linear filtering operation; and perform, based on the one or more parameters, a conversion between the current video region and a bitstream of the video, wherein at least one first filtering index is derived, and a first clipping parameter set is derived based on the at least one first filtering index and the one or more parameters, and wherein the one or more parameters are coded with a fixed length of N bits, wherein the at least one first filtering index is derived based on multiple sample differences in different directions, wherein the current video region is split into multiple M×M video sub-regions, and the multiple sample differences in different directions are derived for every M×M video sub-region, wherein M is equal to 2 or 4, and wherein the multiple sample differences in different directions are derived based on a 1:P subsampling rate, and wherein P is greater than 1. ### Claim 16 (depends on 15) The non-transitory computer-readable storage medium of claim 15, wherein N is 2, wherein the one or more parameters include a clipping index syntax element, wherein a first filtering coefficient set is derived based on the at least one first filtering index and a coefficient parameter syntax element, wherein a value of the clipping index syntax element is determined independently from the first filtering coefficient set, wherein in a case that values of the first filtering coefficient set are zero, the clipping index syntax element is included in the bitstream, wherein the one or more parameters are included as fields in an adaptive parameter set, wherein the clipping index syntax element and the coefficient parameter syntax element are present in a same adaptive parameter set, wherein the coefficient parameter syntax element includes a coefficient absolute value, wherein the coefficient parameter syntax element is coded using Exponential-Golomb model with fixed order, and wherein the current video region includes a coding tree block or a slice. ### Claim 17 A method for storing a bitstream of a video, comprising: determining, that a non-linear filtering operation is applied for a current video region of the video; determining, for the current video region, one or more parameters of a clipping operation that is part of the non-linear filtering operation; generating, based on the one or more parameters, for the current video region, the bitstream of the video, and storing the bitstream in a non-transitory computer-readable recording medium, wherein at least one first filtering index is derived, and a first clipping parameter set is derived based on the at least one first filtering index and the one or more parameters, and wherein the one or more parameters are coded with a fixed length of N bits, wherein the at least one first filtering index is derived based on multiple sample differences in different directions, wherein the current video region is split into multiple M×M video sub-regions, and the multiple sample differences in different directions are derived for every M×M video sub-region, wherein M is equal to 2 or 4, and wherein the multiple sample differences in different directions are derived based on a 1:P subsampling rate, and wherein P is greater than 1. ### Claim 18 (depends on 17) The method of claim 17, wherein N is 2, wherein the one or more parameters include a clipping index syntax element, wherein a first filtering coefficient set is derived based on the at least one first filtering index and a coefficient parameter syntax element, wherein a value of the clipping index syntax element is determined independently from the first filtering coefficient set, wherein in a case that values of the first filtering coefficient set are zero, the clipping index syntax element is included in the bitstream, wherein the one or more parameters are included as fields in an adaptive parameter set, wherein the clipping index syntax element and the coefficient parameter syntax element are present in a same adaptive parameter set, wherein the coefficient parameter syntax element includes a coefficient absolute value, wherein the coefficient parameter syntax element is coded using Exponential-Golomb model with fixed order, and wherein the current video region includes a coding tree block or a slice.