Patent ID: 7203234

Claim:
A method of post processing a decompressed image comprising the steps of: (a) selecting a block of image pixels for filtering as a function of a quantization parameter and a quantization parameter threshold; (b) detecting an approximate direction of an image edge in a block of image pixels and establishing a filtering axis relatively parallel to said direction, wherein the step of establishing a filtering axis relatively parallel to an image edge in said block comprises the steps of: (i) designating a plurality of candidate axes; (ii) identifying a first pixel and a second pixel located on a projection parallel to a candidate axis, said first pixel located in a vicinity of a first boundary of said block and said second pixel located in a vicinity of a second boundary; (iii) determining a difference between said first pixel and said second pixel; (iv) repeating steps (ii) and (iii) for said plurality of candidate axes; and (v) identifying as said filtering axis said candidate axis corresponding to a function of a minimum difference between said first and said second pixels; (c) identifying a filtering segment comprising a plurality of contiguous pixels arrayed substantially parallel to said filtering axis and intersected by a boundary of said block; (d) selectively filtering said pixels of said filtering segment.