An improved EZW algorithm for image compression

This paper presents an improved EZW algorithm for massive image compression. This method divides the massive image into some sub-blocks. Based on the wavelet transformation for these sub-blocks, it first uses EZW coding for them and then uses Huffman coding for them. This method can ensure that makes the best use of the hierarchy relationship of wavelet coefficients and also can improve the compress rate. The authors brings out an adaptive reading/writing method according to the size of image, which is composed of two parts - strip reading/writing and block reading/writing, the cache mechanisms of these two parts are also introduced in this paper. The authors apply this method into browsing massive image on Web and get a good effect.