Patent ID: 7869523

Claim:
A method of filtering reconstructed samples to minimize coding artifacts introduced at a block boundary in a block-based video encoder and/or decoder, the method comprising: calculating a pair of indices used to access a table of a pair of corresponding activity threshold values, the indices calculated using an average quantization parameter and an offset parameter; determining the activity threshold values based on the pair of indices; confirming whether the filtering process will modify the sample values on every line of samples for the block boundary by checking a content activity for the every line of samples for said block boundary, the content activity based on the determined activity threshold values; and filtering the confirmed samples when a block on either side of the block boundary was coded using inter prediction wherein a pair of the activity threshold values are ALPHA (α) and BETA (β), and the average quantization parameter, QP av , was used in coding the two blocks that neighbor the block boundary wherein the values of the activity threshold values, ALPHA (α) and BETA (β) for each possible value of the indices Index A and Index B are Index A (for α) or Index B (for β) 0 1 2 3 4 5 6 7 8 9 10 11 α 0 0 0 0 0 0 0 0 0 0 0 0 β 0 0 0 0 0 0 0 0 0 0 0 0 Index A (for α) or Index B (for β) 12 13 14 15 16 17 18 19 20 21 22 23 α 0 0 0 0 4 4 5 6 7 8 9 10 β 0 0 0 0 2 2 2 3 3 3 3 4 Index A (for α) or Index B (for β) 24 25 26 27 28 29 30 31 32 33 34 α 12 13 15 17 20 22 25 28 32 36 40 β 4 4 6 6 7 7 8 8 9 9 10 Index A (for α) or Index B (for β) 35 36 37 38 39 40 41 42 43 44 α 45 50 56 63 71 80 90 101 113 127 β 10 11 11 12 12 13 13 14 14 15 Index A (for α) or Index B (for β) 45 46 47 48 49 50 51 α 144 162 182 203 226 255 255 β 15 16 16 17 17 18 18