Image restoration of JPEG coded images using mean removed classified vector quantization

Abstract

Image compression techniques are frequently applied for reducing the requirement of network bandwidth and storage space. To remove the artifacts and improve the quality of compressed images, a mean-removed classified vector quantization (MRCVQ) algorithm is proposed. The algorithm extends and modifies vector quantization (VQ) to discover the relationships between the uncompressed color images and their deblocked compressed versions by classifying the deblocked compressed blocks into several categories using information from their neighboring blocks. The discovered relationships are stored in two codebooks and used to recover the missing information of compressed color images. The experimental results show that the proposed algorithm can remove the artifacts and improve the quality of compressed color images effectively.