Blocking Artifacts Reduction using Two Modes Shift Block Filter

Blocking effect is the major drawbacks in DCT-based codec at low bit-rate. An efficient anti-blocking effect algorithm is induced in the DCT domain. The proposed algorithm eases the false edges with low computational complexity. Two operations are suggested to different region according the region feature. One operation applies to the smooth region and the boundary edges become to linear distribution and more gradual. The other operation tries to remove some high frequency DCT component and to make the false edge smoothness but not harm for the image quality. The proposed scheme can take best quality in both objective and subjective metrics. Moreover, the objective metric, Peak Signal-to-Noise Ratio (PSNR), can improve to 0.5 dB.