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采用MATLAB实现图像信息隐藏。将文本信息，通过DCT和LSB算法嵌入到二维图像中实现信息隐藏。(hide information into voice signal with the methods of DCT and LSB)

Calculate hurst and lyupanov exponent from a time serie

根据输入的本原多项式系数、级数、延迟相位产生一个m序列。。(creat a m sequence )

这是个用Durbin递归求预测误差滤波器和他的输出，是电子所邹谋炎老师给出的例程。(This is a demand by Durbin recursive prediction error filter, and his output is of Electronics Zou Mou-Yan teachers given routine.)

图像的低通滤波器,用MATLAB设计一个3×3模板标准差为0.5的高斯低通滤波。(Image low-pass filter MATLAB design, a standard template for 3 x 3 0.5 gaussian low-pass filter)

bsxfun, 一個matlab中十分常用的函數. 可以快速地對matrix進行接位複合運算~~(bsxfun, a very commonly used in the matlab function. can quickly take place on the matrix for composite operator ~ ~)

Simulink简明教程，快速入门，建模方法，运行仿真等(Simulink simple tutorial)

ch3=softt(h3,thr1 clear clc I=imread( lena512.bmp ) imshow(I) I=double(I) II=I+30*randn(size(I)) figure imshow(II,[]) [a1,h1,v1,d1]=dwt2(II, sym8 ) [a2,h2,v2,d2]=dwt2(a1, sym8 ) [a3,h3,v3,d3]=dwt2(a2, sym8 ) sigma=median(abs(d1(:)))/0.6745 x=3*sigma thr1=x*2^(-1) thr2=x*2^(-0.5) thr3=x 小波图像去噪( ch3=softt(h3,thr1 clear clc I=imread( lena512.bmp ) imshow(I) I=double(I) II=I+30*randn(size(I)) figure imshow(II,[]) [a1,h1,v1,d1]=dwt2(II, sym8 ) [a2,h2,v2,d2]=dwt2(a1, sym8 ) [a3,h3,v3,d3]=dwt2(a2, sym8 ) sigma=median(abs(d1(:)))/0.6745 x=3*sigma thr1=x*2^(-1) thr2=x*2^(-0.5) thr3=x )

使用matlab画圆，对图傅里叶变化，零频移中，反变换实验(test fft and ifft)

说明：  光谱数据预处理之小波去噪，包含两个数据文件(Wavelet denoising for spectral data preprocessing)