Deblocking of block-DCT compressed images using deblocking frames of variable size

A new algorithm for the removal of blocking artifacts in block-DCT compressed images and video sequences is proposed in this paper. The algorithm uses deblocking frames of variable size (DFOVS). A deblocking frame is a square of pixels which overlaps image blocks. Deblocking is achieved by applying weighted summation on pixels quartets which reside in deblocking frames. The pixels in a quartet are symmetrically aligned with respect to block boundaries. The weights are determined according to a special 2-D function and a predefined factor, we refer to as a grade. A pixel´s grade is determined according to the amount of details in its neighborhood. Deblocking of monotone areas is achieved by iteratively applying deblocking frames of decreasing sizes on such areas. This new algorithm produces very good subjective results and PSNR results which are competitive relative to available state-of-the-art methods.