Lossless acceleration of fractal compression using domain and range block local variance analysis

A problem of speeding-up the fractal compression of still images is discussed. The techniques based on analysis of local variance for range blocks and domain blocks are proposed and considered. An algorithm for fast search of domain blocks corresponding to the range block in the best manner is described. It is shown that a reduction of search CPU time by several times can be provided and the obtained benefit depends upon the complexity of image to be compressed and the range block size. The proposed procedure for speeding up the fractal compression does not result in additional losses in recovered image quality.