id summary reporter owner description type status priority milestone component version resolution keywords cc 1151 Issue in equation 1269 and 1270 of deblocking filter in the specification text chhuanb "There seems to be a bug in the derivaion of the number of deblocking processing unit for chroma. According to my understanding, for YUV420, the processing unit size for an edge is 2-pixel for chroma. For example, if edgeType is EDGE_VER and nCbH is 8, the edge is divided into 4 units, with each unit containing 2-pixel rows. However, according to equation 1270, ""yN = edgeType = = EDGE_VER ? ( nCbH / 4 / subH ) − 1 : Max( 0, ( nCbH / gridSize ) − 1 )"" below, if ((edgeType == EDGE_VER) && (nCbH == 8) && (subH == 2)) , yN will be 0, instead of 3. '''8.8.3.6 Edge filtering process for one direction '''– The variable gridSize is set as follows: gridSize = cIdx = = 0 ? 4 : 8 (1266) – The variables subW, subH, xN, yN are derived as follows: subW = cIdx = = 0 ? 1 : SubWidthC (1267) subH = cIdx = = 0 ? 1 : SubHeightC (1268) xN = edgeType = = EDGE_VER ? Max( 0, ( nCbW / gridSize ) − 1 ) : ( nCbW / 4 / subW ) − 1 (1269) yN = edgeType = = EDGE_VER ? ( nCbH / 4 / subH ) − 1 : Max( 0, ( nCbH / gridSize ) − 1 ) (1270) Should it be: xN = edgeType = = EDGE_VER ? Max( 0, ( nCbW / gridSize ) − 1 ) : ( nCbW / '''(4 / subW)''' ) − 1 (1269) yN = edgeType = = EDGE_VER ? ( nCbH / '''(4 / subH)''' ) − 1 : Max( 0, ( nCbH / gridSize ) − 1 ) (1270)" defect closed minor VVC D10 spec fixed ksuehring bbross XiangLi fbossen jvet@…