| The DCT was used as the main method of image transform coding for a long time. But there is obvious "block noise" in this transform coding method useing DCT. And it is difficult to improve the compression performance. Wavelet transform becomes the main subject of image compression coding for it has the advantage of describing non-steady signal. In this paper, we begin with the analysis of wavelet transform. After the analysis of image wavelet coefficients and methods of image compression, a method of vector-constitution among different subbands, making verctor book using PCC+LBG, and fast VQ is presented. At the same time a better compression performance is improved by using multistage vector algorithm, the design of this algorithm based on DSPs is given at the end of this paper.
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