Reduction of blocking artifacts for low bit-rate video coding using regularized dequantization

Most discrete cosine transform (DCT) based video coding suffers from blocking artifacts, where boundaries of 8×8 DCT blocks become visible on decoded images. The blocking artifacts become more prominent as the bit rate is lowered. In this paper, we present a new dequantization technique for DCT-based encoding to sharply reduce the blocking artifacts. Our proposed dequantization scheme, through regularization, sharply reduces blocking artifacts in decoded images. The performance the proposed algorithm is compared to that of the currently specified H.263+ Annex J deblocking filter. The comparison shows visual improvements as well as numerical improvements in terms of the peak signal-to-noise ratio (PSNR) and of a blockiness measure (BM) that is defined