Suppressing the block effect of fractal image compression by smoothing locally with quasi-X shape template

A new method of suppressing the block effect brought about by fractal image compression is proposed by means of introducing quasi-X shape template into the process of smoothing image locally on the reconstructed color image compressed by the fractal method based on iterated function system. The effects of the two different kinds of smooth templates, quasi-X shape and traditional square are compared with each other. It is found that the mosaic effect can be suppressed effectively with the help of quasi-X shape template in the process of smoothing image locally under the condition that certain objective image quality measured by the PSNR value is guaranteed. At the same time, the compression ratio is improved by means of getting rid of the position parameters of range blocks as one kind of redundancy when adopting the method of fractal image compression during the process of compressing color image, taking the fact that range blocks are stored in encoding file successively into account.