用matlab如何实现fft变换

图象增强小波变换将一幅图象分解为大小、位置与方向都不同的分量。在做逆变换之前能改变小波变换域中某些系数的大小，，这样就能够洋选择的放大所感兴趣的分量而减小不需要的分量。给定一个图象信号，用二维小波分析析对图象进行增强处理。 (Image enhancement wavelet transform decomposition size, location and direction of the different components of an image. Wavelet transform domain, some the size of the coefficient can change before doing the inverse transformation, so can the component of interest to the amplification of the ocean choose to reduce the unwanted weight. Given an image signal, the analysis of two-dimensional wavelet analysis of image enhancement processing.)

设定雷达和目标参数，选取目标中心与雷达的距离为参考距离，采取dechirp方式接收信号，直接对回波信号进行二维FFT得到的成像结果，并采用Keystone法（即重采样法）校正越距离单元徙动。(Set the radar and the target parameters, select the center of the target and the distance from the radar as the reference distance, take reception dechirp signal, directly on the echo signals, the imaging results obtained by the two-dimensional FFT, and the Keystone method (i.e., re-sampling) Vietnam correction range cell migration.)

对输入的二维灰值图像，先进行提升Haar小波变换，再用经典的EZW算法对小波系数进行压缩，然后反变换重构原图像。(On the importation of two-dimensional gray value of images, first upgrade the Haar wavelet transform, and then classical EZW algorithm to compress the wavelet coefficients, and then inverse transform reconstruction of the original image.)

美国Rice大学提供的matlab 小波代码，要比matlab自带的matlab更易用(Rice University, USA matlab wavelet code comes than easier to use)

说明：  用c++实现小波变换，参考matlab实现(Using C + + to realize wavelet transform, referring to matlab to realize)

基于MATLAB的虚拟实验系统 的源代码 信号与系统 典型课程的演示实验的编程 GUI(the virtual experiment system for signal processing on the matlab)

基于四阶累积量的矩阵方程法子波估计,对研究子波的有一定的帮助(based on the forth cumulantion seismic wavelet estimation)

说明：  双数复数小波变换的Matlab源码的A部分，全部解压到一个文件夹后直接调用函数。(Double the number of complex wavelet transform of the A part of Matlab source code, all extract to a folder call the function directly.)

single level ,two level, multi level dwt for the denoising

基于matlab小波变换的轴承故障外圈点蚀分析。(Based on wavelet transform matlab punctuate eclipse outer bearing failure analysis.)