# US 11,310,535 B2 · Deblocking filtering control for illumination compensation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,535 B2 - Document ID: US11310535B2 - Status: Granted - Kind: B2 - Application number: 16/628,432 - Filed: 2018-06-21 - Published: 2020-05-21 - Granted: 2022-04-19 - Earliest claimed: 2017-07-05 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget LM Ericsson (publ) - Inventors: Kenneth Andersson; Per Wennersten; Rickard Sjöberg; Ruoyang Yu - Web page: https://patentgrep.com/patent/US11310535B2 ## CPC - H04N 19/86: involving reduction of coding artifacts, e.g. of blockiness - H04N 19/117: Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) - H04N 19/14: Coding unit complexity, e.g. amount of activity or edge presence estimation (H04N19/146 takes precedence) - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/61: in combination with predictive coding - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A deblocking filtering control involves deciding whether to apply deblocking filtering to sample values in a sample block in a picture and in a neighboring sample block in the picture based on i) whether illumination compensation is enabled for sample prediction values in a first prediction block in a reference picture for said sample block and/or ii) whether illumination compensation is enabled for sample prediction values in a second prediction block in said reference picture or another reference picture for said neighboring sample block. The sample block and the neighboring sample block are separated in the picture by a block boundary. This decision to apply deblocking filtering based on whether illumination compensation is enabled reduces blocking artefacts that may otherwise arise in certain pictures of a video sequence. ## Claims ### Claim 1 A deblocking filtering control method comprising: deciding whether to apply deblocking filtering to sample values in a sample block in a picture and in a neighboring sample block in said picture based on i) whether illumination compensation is enabled for sample prediction values in a first prediction block in a reference picture for said sample block and/or ii) whether illumination compensation is enabled for sample prediction values in a second prediction block in said reference picture or another reference picture for said neighboring sample block, said sample block and said neighboring sample block being separated in said picture by a block boundary, wherein the deciding whether to apply deblocking filtering comprises deciding to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; deciding whether to apply strong deblocking filtering or weak deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; and determining a value of at least one parameter selected from a group consisting of parameters β and tc based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; wherein the deciding whether to apply said strong deblocking filtering or said weak deblocking filtering comprises deciding to apply said strong deblocking filtering to said sample values in said sample block and in said neighboring sample block if 2×(|p2i−2p1i+p0i|+|q2i−2q1i+q0i|)<(β>>2), |p3i−p0i|+|q3i−q0i|<(β>>3) and |p0i−q0i|<((5×tc+1)>>1), wherein i=0, 3, and otherwise deciding to apply said weak deblocking filtering to said sample values in said sample block and in said neighboring sample block, wherein p0i denotes a sample value of a first sample, relative to said block boundary, in a line i of samples in said sample block, p1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said sample block, p2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said sample block, q0i denotes a sample value of a first sample, relative to said block boundary, in said line i of samples in said neighboring sample block, q1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said neighboring sample block, and q2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said neighboring sample block. ### Claim 2 (depends on 1) The deblocking filtering control method according to claim 1, wherein the deciding whether to apply deblocking filtering comprises deciding whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) a value of a first Local Illumination Compensation, LIC, parameter for said first prediction block and/or ii) a value of a second LIC parameter for said second prediction block. ### Claim 3 (depends on 2) The deblocking filtering control method according to claim 2, wherein the deciding whether to apply deblocking filtering comprises deciding whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) a value of a first LIC weighting factor for said sample prediction values of said first prediction block and ii) a value of a second LIC weighting factor for said sample prediction values of said second prediction block. ### Claim 4 (depends on 2) The deblocking filtering control method according to claim 2, wherein the deciding whether to apply deblocking filtering comprises deciding whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) a value of a first LIC additive offset for said sample prediction values of said first prediction block and ii) a value of a second LIC additive offset for said sample prediction values of said second prediction block. ### Claim 5 (depends on 2) The deblocking filtering control method according to claim 2, further comprising: comparing a first magnitude modification of sample prediction values from the first LIC parameter and a second magnitude modification of sample prediction values from the second LIC parameter, wherein: the first magnitude modification and the second magnitude modification include weights and/or offsets for the sample prediction values; and deciding whether to apply deblocking filtering comprises deciding whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on said comparison of said first magnitude modification of sample prediction values and said second magnitude modification of sample prediction values. ### Claim 6 (depends on 1) The deblocking filtering control method according to claim 1, wherein the deciding whether to apply deblocking filtering comprises: deciding that deblocking filtering may be applied to said sample values in said sample block and in said neighboring sample block if said first LIC parameter differs from said second LIC parameter with at least a threshold value; and deciding not to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block if said first LIC parameter does not differ from said second LIC parameter with at least said threshold value. ### Claim 7 (depends on 1) The deblocking filtering control method according to claim 1, further comprising: determining a value of a boundary strength parameter based on whether illumination compensation is enabled, wherein the deciding whether to apply deblocking filtering comprises deciding whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on said value of said boundary strength parameter. ### Claim 8 A deblocking filtering control device, wherein said deblocking filtering control device is configured to: decide whether to apply deblocking filtering to sample values in a sample block in a picture and in a neighboring sample block in said picture based on i) whether illumination compensation is enabled for sample prediction values in a first prediction block in a reference picture for said sample block and/or ii) whether illumination compensation is enabled for sample prediction values in a second prediction block in said reference picture or another reference picture for said neighboring sample block, said sample block and said neighboring sample block being separated in said picture by a block boundary; decide whether to apply strong deblocking filtering or weak deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; and determine a value of at least one parameter selected from a group consisting of parameters β and tc based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; wherein said deblocking filtering control device is configured to decide whether to apply said strong deblocking filtering or said weak deblocking filtering comprises deciding to apply said strong deblocking filtering to said sample values in said sample block and in said neighboring sample block if 2×(|p2i−2p1i+p0i|+|q2i−2q1i+q0i|)<(β>>2), |p3i−p0i|+|q3i−q0i|<(β>>3) and |p0i−q0i|<((5×tc+1)>>1), wherein i=0, 3, and otherwise deciding to apply said weak deblocking filtering to said sample values in said sample block and in said neighboring sample block, wherein p0i denotes a sample value of a first sample, relative to said block boundary, in a line i of samples in said sample block, p1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said sample block, p2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said sample block, q0i denotes a sample value of a first sample, relative to said block boundary, in said line i of samples in said neighboring sample block, q1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said neighboring sample block, and q2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said neighboring sample block. ### Claim 9 (depends on 8) The deblocking filtering control device according to claim 8, wherein said deblocking filtering control device is configured to decide whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) a value of a first Local Illumination Compensation, LIC, parameter for said first prediction block and/or ii) a value of a second LIC parameter for said second prediction block. ### Claim 10 (depends on 9) The deblocking filtering control device according to claim 9, wherein said deblocking filtering control device is configured to decide whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) a value of a first LIC weighting factor for said sample prediction values of said first prediction block and ii) a value of a second LIC weighting factor for said sample prediction values of said second prediction block. ### Claim 11 (depends on 9) The deblocking filtering control device according to claim 9, wherein said deblocking filtering control device is configured to decide whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) a value of a first LIC additive offset for said sample prediction values of said first prediction block and ii) a value of a second LIC additive offset for said sample prediction values of said second prediction block. ### Claim 12 (depends on 9) The deblocking filtering control device according to claim 9, wherein said deblocking filtering control device is further configured to: compare a first magnitude modification of sample prediction values from the first LIC parameter and a second magnitude modification of sample prediction values from the second LIC parameter, wherein: the first magnitude modification and the second magnitude modification include weights and/or offsets for the sample prediction values; and said deblocking filtering control device is configured to decide whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on said comparison of said first magnitude modification of sample prediction values and said second magnitude modification of sample prediction values. ### Claim 13 (depends on 8) The deblocking filtering control device according to claim 8, wherein said deblocking filtering control device is configured to: decide that deblocking filtering may be applied to said sample values in said sample block and in said neighboring sample block if said first LIC parameter differs from said second LIC parameter with at least a threshold value; and decide not to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block if said first LIC parameter does not differ from said second LIC parameter with at least said threshold value. ### Claim 14 (depends on 8) The deblocking filtering control device according to claim 8, wherein said deblocking filtering control device is further configured to determine a value of a boundary strength parameter based on whether illumination compensation is enabled, wherein said deblocking filtering control device is configured to decide whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on said value of said boundary strength parameter. ### Claim 15 (depends on 8) The deblocking filtering control device according to claim 8, comprising: a processor; and a memory comprising instructions executable by said processor, wherein said processor is operative to: decide whether to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on i) whether illumination compensation is enabled for sample prediction values in said first prediction block in said reference picture for said sample block and/or ii) whether illumination compensation is enabled for sample prediction values in said second prediction block in said reference picture or the other reference picture for said neighboring sample block, said sample block and said neighboring sample block being separated in said picture by said block boundary; decide whether to apply strong deblocking filtering or weak deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; and determine said value of at least one parameter selected from said group consisting of parameters β and tc based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; wherein said deblocking filtering control device is configured to decide whether to apply said strong deblocking filtering or said weak deblocking filtering comprises deciding to apply said strong deblocking filtering to said sample values in said sample block and in said neighboring sample block if 2×(|p2i−2p1i+p0i|+|q2i−2q1i+q0i|)<(β>>2), |p3i−p0i|+|q3i−q0i|<(β>>3) and |p0i−q0i|<((5×tc+1)>>1), wherein i=0, 3, and otherwise deciding to apply said weak deblocking filtering to said sample values in said sample block and in said neighboring sample block, wherein p0i denotes said sample value of said first sample, relative to said block boundary, in said line i of samples in said sample block, p1i denotes said sample value of said second sample, relative to said block boundary, in said line i of samples in said sample block, p2i denotes said sample value of said third sample, relative to said block boundary, in said line i of samples in said sample block, q0i denotes said sample value of said first sample, relative to said block boundary, in said line i of samples in said neighboring sample block, q1i denotes said sample value of said second sample, relative to said block boundary, in said line i of samples in said neighboring sample block, and q2i denotes said sample value of said third sample, relative to said block boundary, in said line i of samples in said neighboring sample block. ### Claim 16 A deblocking filtering control device comprising a decision module for: deciding whether to apply deblocking filtering to sample values in a sample block in a picture and in a neighboring sample block in said picture based on i) whether illumination compensation is enabled for sample prediction values in a first prediction block in a reference picture for said sample block and/or ii) whether illumination compensation is enabled for sample prediction values in a second prediction block in said reference picture or another reference picture for said neighboring sample block, said sample block and said neighboring sample block being separated in said picture by a block boundary, wherein the deciding whether to apply deblocking filtering comprises deciding to apply deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; deciding whether to apply strong deblocking filtering or weak deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; and determining a value of at least one parameter selected from a group consisting of parameters β and tc based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; wherein the deciding whether to apply said strong deblocking filtering or said weak deblocking filtering comprises deciding to apply said strong deblocking filtering to said sample values in said sample block and in said neighboring sample block if 2×(|p2i−2p1i+p0i|+|q2i−2q1i+q0i|)<(β>>2), |p3i−p0i|+|q3i−q0i|<(β>>3) and |p0i−q0i|<((5×tc+1)>>1), wherein i=0, 3, and otherwise deciding to apply said weak deblocking filtering to said sample values in said sample block and in said neighboring sample block, wherein p0i denotes a sample value of a first sample, relative to said block boundary, in a line i of samples in said sample block, p1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said sample block, p2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said sample block, q0i denotes a sample value of a first sample, relative to said block boundary, in said line i of samples in said neighboring sample block, q1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said neighboring sample block, and q2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said neighboring sample block. ### Claim 17 A non-transitory computer-readable storage medium comprising a computer program product comprising instructions, which when executed by at least one processor, cause said at least one processor to: decide whether to apply deblocking filtering to sample values in a sample block in a picture and in a neighboring sample block in said picture based on i) whether illumination compensation is enabled for sample prediction values in a first prediction block in a reference picture for said sample block and/or ii) whether illumination compensation is enabled for sample prediction values in a second prediction block in said reference picture or another reference picture for said neighboring sample block, said sample block and said neighboring sample block being separated in said picture by a block boundary; decide whether to apply strong deblocking filtering or weak deblocking filtering to said sample values in said sample block and in said neighboring sample block based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; and determine a value of at least one parameter selected from a group consisting of parameters β and tc based on whether illumination compensation is enabled for at least one of said sample block and said neighboring sample block; wherein said deblocking filtering control device is configured to decide whether to apply said strong deblocking filtering or said weak deblocking filtering comprises deciding to apply said strong deblocking filtering to said sample values in said sample block and in said neighboring sample block if 2×(|p2i−2p1i+p0i|+|q2i−2q1i+q0i|)<(β>>2), |p3i−p0i|+|q3i−q0i|<(β>>3) and |p0i−q0i|<((5×tc+1)>>1), wherein i=0, 3, and otherwise deciding to apply said weak deblocking filtering to said sample values in said sample block and in said neighboring sample block, wherein p0i denotes a sample value of a first sample, relative to said block boundary, in a line i of samples in said sample block, p1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said sample block, p2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said sample block, q0i denotes a sample value of a first sample, relative to said block boundary, in said line i of samples in said neighboring sample block, q1i denotes a sample value of a second sample, relative to said block boundary, in said line i of samples in said neighboring sample block, and q2i denotes a sample value of a third sample, relative to said block boundary, in said line i of samples in said neighboring sample block.