US 12,407,823 B2
Adaptive loop filter (ALF) virtual boundry processing
Kenneth Andersson, Gävle (SE); Jacob Ström, Stockholm (SE); Zhi Zhang, Solna (SE); and Jack Enhorn, Kista (SE)
Assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), Stockholm (SE)
Appl. No. 17/915,579
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Apr. 1, 2021, PCT No. PCT/EP2021/058686
§ 371(c)(1), (2) Date Sep. 29, 2022,
PCT Pub. No. WO2021/198456, PCT Pub. Date Oct. 7, 2021.
Claims priority of provisional application 63/004,048, filed on Apr. 2, 2020.
Prior Publication US 2023/0164312 A1, May 25, 2023
Int. Cl. H04N 19/117 (2014.01); H04N 19/132 (2014.01); H04N 19/176 (2014.01); H04N 19/423 (2014.01)
CPC H04N 19/117 (2014.11) [H04N 19/132 (2014.11); H04N 19/176 (2014.11); H04N 19/423 (2014.11)] 8 Claims
OG exemplary drawing
 
1. A method for processing an image, the method comprising:
obtaining a set of sample values associated with the image, the set of sample values comprising a current sample value and sample values neighboring the current sample value, wherein the obtained set of sample values is included within a rectangular block of sample values, and the current sample value has a vertical position, y;
selecting a filter strength value based on y, wherein selecting the filter strength value based on y comprises: selecting a first filter strength value if a condition is satisfied, otherwise if the condition is not satisfied selecting a second filter strength value, wherein the condition is satisfied if and only if y is equal to a single predetermined value and zero or more other criterions are satisfied and the condition is not satisfied for every value of y that is not equal to the predetermined value; and
filtering the current sample based on the selected filter strength value.