实验三图像处理

1、通信与信息工程学院MATLAB实验报告班 级：电子信息科学与技术12级02班姓 名：徐明学 号：1107080232设计时间：2014.3.3 - 2014.4.30通信与信息工程学院二一四年实验三 图像处理【实验内容】1. MATLAB中关于图像处理的部分语句表1 MATLAB图像处理工具箱中常用的语句命令功能图像显示imagesubimageimagescimshowtruesize建立并显示图像在一个图形窗口中显示多个图像调整数据并显示成图像图像显示调整图像显示大小图像文件输入输出imreadimwriteiminfoloadsave图像文件读入图像写出查看图像文件信息将以mat为扩展名

2、的图像文件调入到内存将内存变量中的图像保存到以mat为扩展名的文件中图像几何运算imcropimresizeimrotate图像剪裁图像大小调整图像旋转图像像素值及统计imhistmean2std2corr2求图像数据直方图求均值求标准差求相关系数图橡增强及平滑imadjusthisteqimnoise medfilt2对比度调整直方图均衡给图像增加噪声二维中值滤波器图像变换fft2ifft2dct2idct2dctmtx计算二维FFT计算二维逆FFT计算2D离散余弦变换计算2D反离散余弦变换计算DCT矩阵其它conv2convmtx2xcorr2二维卷积计算二维卷积矩阵二维互相关1-1 读取

3、RGB彩色图像，采用rgb2gray( ) 函数将其转化为灰度图像语法：I = rgb2gray(RGB) converts the truecolor image RGB to the grayscale intensity image I.程序：I=imread('lenna_color.tiff');G = rgb2gray(I);subplot(1,2,1);imshow(I);subplot(1,2,2);imshow(G);1-2 读取tougu.bmp和fei.bmp灰度图像，分别采用imhist( ) 函数绘制它们的图像直方图，并采用直方图均匀化histeq（）

4、函数进行增强处理。语法：1、直方图函数 imhist(I,n)imhist(I,n) displays a histogram with n bins for the intensity image I above a grayscale colorbar of length n. If you omit the argument, imhist uses a default value of n = 256 if I is a grayscale image, or n = 2 if I is a binary image.2、直方图均衡化函数 J = histeq(I, hgram)J =

5、 histeq(I, hgram) transforms the intensity image I so that the histogram of the output intensity image J with length(hgram) bins approximately matches hgram. The vector hgram should contain integer counts for equally spaced bins with intensity values in the appropriate range: 0, 1 for images of clas

6、s double, 0, 255 for images of class uint8, and 0, 65535 for images of class uint16. histeq automatically scales hgram so that sum(hgram) = prod(size(I). The histogram of J will better match hgram when length(hgram) is much smaller than the number of discrete levels in I.程序：A=imread('source.BMP&

7、#39;);B=imread('rice.bmp');K=histeq(A);V=histeq(B);subplot(2,3,1),imshow(A);subplot(2,3,2), imhist(A);subplot(2,3,3),imshow(K);subplot(2,3,4),imshow(B);subplot(2,3,5), imhist(B);subplot(2,3,6),imshow(V);实验结果：1-3 读取灰度图像，分别对图像进行二维快速傅里叶变换和二维快速傅里叶反变换，二维离散余弦变换和二维离散余弦反变换。并分别显示出变换后的图像。语法：1、二维快速傅里叶变

8、换 Y = fft2(X)Y = fft2(X) returns the two-dimensional discrete Fourier transform (DFT) of X, computed with a fast Fourier transform (FFT) algorithm. The result Y is the same size as X.2、二维快速傅里叶反变换 Y = ifft2(X)Y = ifft2(X) returns the two-dimensional inverse discrete Fourier transform (DFT) of X, comp

9、uted with a fast Fourier transform (FFT) algorithm. The result Y is the same size as X.3、二维离散余弦变换 B = dct2(A)B = dct2(A) returns the two-dimensional discrete cosine transform of A. The matrix B is the same size as A and contains the discrete cosine transform coefficients B(k1,k2).4、二维离散余弦反变换 B = idc

10、t2(A)B = idct2(A) returns the two-dimensional inverse discrete cosine transform (DCT) of A.程序：I=imread('finger.bmp');X = fft2(I);Y = ifft2(I);Z= dct2(I);B = idct2(I);subplot(2,3,1);imshow(I);subplot(2,3,2);imshow(X);subplot(2,3,3);imshow(Y);subplot(2,3,4);imshow(Z);subplot(2,3,5);imshow(B);

11、1-4 读取灰度图像，采用imnoise（）函数对图像进行加噪处理并显示噪声图像，同时采用中值滤波函数medfilt2（）对噪声图像进行去噪处理并显示去噪后图像。语法：1、图像加噪函数 J = imnoise(I,type)J = imnoise(I,type) adds noise of given type to the intensity image I. type is a string that can have one of these values: 'gaussian' for Gaussian white noise 'localvar' for zero-mean Gaussian white noise with an intensity-dependent variance 'poisson' for Poisson noise 'salt & pepper' for "on and off" pixels 'speckle' for multiplicative noise。2、二维中值过滤函数 B = medfilt2(A)B = medfilt2(A) performs median filtering of t