In order to reduce image coding time

a new fast fractal method based on wavelet decomposition is presented in this paper. This algorithm is mainly implemented in two fold. Firstly

according to the feature of wavelet decomposition whose energy is ununiformity distribution in subbands of whole wavelet transform image

the low frequency region

where most of energy concentrates

is regarded as a kind of image

and can be encoded with traditional fractal method. Secondly

owing to the similarity of subband image among different channels after wavelet decomposition

instead of global search mechanism we have introduced a local optimal solution to gain the whole image's fractal parameter by suitable scale transform of low frequency region's. The analysis and results show that the encoding speed is improved greatly in case of the fixed compression ratio

and the quality of the reconstructed image can be better retained. It's very evidently that the dissymmetry between the encoding and decoding process has been reformed drastically.