The new algorithm research of frequency sharing embedded zerotree wavelets encoding

EZW takes equal important code for all frequencies, so it can´t make use of the characteristics of the wavelet´s coefficient completely. The coding time is too long and the coding efficiency is low during the process of gradually approximating and quantizing, so we put forward the separate-frequency EZW. This algorithm codes the high and low frequencies of wavelet image respectively. And the results of experiment show that the algorithm has raised the compress ratio further on the premise of instauration picture having a good visual-effectiveness.