Bit rate and blocking artifact reduction by iterative pre-distortion

Block transform coding is widely used in image and video compression methods. Due to quantization error, there are blocking artifacts in the decoded image. This paper presents a pre-processing method, called pre-distortion, to reduce both the bitrate and blocking artifacts. The proposed algorithm is an iterative algorithm which reduces the blocking artifacts of the decoded image by introducing distortion intentionally in the encoding process. Simulation shows that, with pre-distortion, additional compression can be achieved with slight degradation in visual quality. Moreover, the blocking artifacts of the decoded image are reduced.