Color FIC by Zero-Mean Method

In this paper, a fractal compression technique based on zero-mean block matching is utilized as unconventional affine mapping. In this method the mean of the range blocks is used instead of traditional offset parameter. This will reduce and simplify the computations of the affine parameter during the encoding process. This method is tested on 24 bits/pixel color image. The data of the color compression (R,G,B) are transformed to (Y,U,V) components, to take the advantage of the existing spectral correlation to gain more compression. Also the low spatial resolution of the human vision systems to the chromatic components (U,V) is utilized to increase the compression ratio without making significant subjective distortion. The test results led to encoding time (104.81) sec, compression ratio (10.97) and PSNR (32.47). These results show reduction in the encoding time about 18%, and increase in compression ratio around 13%. The image quality was nearly preserved in comparison with traditional method. Also the number of iteration required to construct the attractors is less than that required in the traditional method.