小波变换是近几年发展起来的集数学、科学计算及信号处理于一体的新理论，其核心是多分辨率分析。本文全面综述了小波变换作为多分辨率图象处理新工具的发展过程、小波变换的定义、信号／图象的多分辨率小波分解及图象多分辨率分解所表现的多尺度特性、局部化分析特性及方向选择性等。

Wavelett ransform is a new powerful tool developed in recent years,which includes mathmatics、scientific computation and signal processing. Its key is multiresolution analysis. This paper completely reviews the process of the wavelet development as multiresolution tool、difinition of wavelet transform、wavelet decompositions of signals and images、and the multiscale、local time frequency and orientation characteristics of multiresolution image decomposition and so on.