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用MATLAB编程实现实现滤波，与数字信号处理相关(Implementing filtering)

基础应用基于小波变换阈值去噪的MATLAB源代码（包含小波包去噪程序）(Based on the application based on wavelet transform threshold denoising MATLAB source code (including the wavelet packet denoising procedures ))

图像小波变换，小波变换（wavelet transform，WT）是一种新的变换分析方法，它继承和发展了短时傅立叶变换局部化的思想，同时又克服了窗口大小不随频率变化等缺点，能够提供一个随频率改变的“时间-频率”窗口，是进行信号时频分析和处理的理想工具。它的主要特点是通过变换能够充分突出问题某些方面的特征，能对时间（空间）频率的局部化分析，通过伸缩平移运算对信号（函数)逐步进行多尺度细化，最终达到高频处时间细分，低频处频率细分，能自动适应时频信号分析的要求，从而可聚焦到信号的任意细节，解决了Fourier变换的困难问题，成为继Fourier变换以来在科学方法上的重大突破。(Image Wavelet Transform)

说明：  针对不同采样频率和输入信噪比的心磁信号进行滤波操作，呈现出对同一输入信号采取不同滤波算法的去噪结果。(The filtering operation is performed on the magnetic heart signals of different sampling frequencies and input signal-to-noise ratios, showing the denoising results of different filtering algorithms for the same input signal.)

its c-wavelet transform

Block-based random image sampling is coupled with a projectiondriven compressed-sensing recovery that encourages sparsity in the domain of directional transforms simultaneously with a smooth reconstructed image. Both contourlets as well as complex-valued dual-tree wavelets are considered for their highly directional representation, while bivariate shrinkage is adapted to their multiscale decomposition structure to provide the requisite sparsity constraint. Smoothing is achieved via a Wiener filter incorporated into iterative projected Landweber compressed-sensing recovery, yielding fast reconstruction. The proposed approach yields images with quality that matches or exceeds that produced by a popular, yet computationally expensive, technique which minimizes total variation. Additionally, reconstruction quality is substantially superior to that from several prominent pursuits-based algorithms that do not include any smoothing

采用小波变换的方法实现心电信号的滤波，分别使用了硬阈值、软阈值和改进阈值方法，并实现了滤波效果的评价（均方差和信噪比）(Wavelet transform of ECG signal filtering method, respectively, using a hard threshold and soft threshold and improve the threshold method, and to achieve the filtering effect of the evaluation (both variance and signal to noise ratio))

基于第二代小波的非抽样小波变换应用程序，可以用来小波转换(Non-sampling based on second generation wavelets, wavelet transform application)

嵌入式小波图像编码即EZW是最近很流行的一种编码方式，我的程序是用matlab实现对EZW的描述。(Embedded Wavelet EZW image coding that is very popular recently as a way of coding, I use the matlab process is to achieve a description of the EZW.)

使用DCT和小波变换的数字音频水印生成/解码程序，可存活于方差0.05的高斯白噪声及不同程度的剪切。内含程序/测试文件介绍。(Digital wartermarking encoding/decoding program with DCT and wavelet transform. nice robustness against Gaussian noise with variance less than 0.05 and any type of cropping attack. functions/test files introduction included)