Wavelets for image compression

The wavelet transform is becoming increasingly important in image compression applications because of its flexibility in representing nonstationary signals. Current techniques use exhaustive search procedures that are computationally intensive to find the “optimal” basis (type, order, tree). In this paper, we propose some guidelines based on the statistics of the image to be coded, for determining the need to search for the “optimal” wavelets as well as the improvement that can be achieved by using the “optimal” over “standard” wavelets. The proposed guidelines can be used to find a good initial guess for the exhaustive search if the optimal basis is needed