MATLAB图像增强程序举例.doc

MATLAB图像增强程序举例1.灰度变换增强程序：% GRAY TRANSFORMclc;I=imread(pout.tif);imshow(I);J=imadjust(I,0.3 0.7,0 1,1);%transforms the walues in the %intensity image I to values in J by linealy mapping %values between 0.3 and 0.7 to values between 0 and 1.figure;imshow(J);J=imadjust(I,0.3 0.7,0 1,0.5);% if GAMMA is less than 1,the mapping si weighted toward higher (brighter)%output values.figure;imshow(J);J=imadjust(I,0.3 0.7,0 1,1.5);% if GAMMA is greater than 1,the mapping si weighted toward lower (darker)%output values.figure;imshow(J)J=imadjust(I,0.3 0.7,0 1,1);% If TOPBOTTOM,the output image is reversed,as in a photographic negative.figure;imshow(J);2.直方图灰度变换%直方图灰度变换X,map=imread(forest.tif);I=ind2gray(X,map);%把索引图像转换为灰度图像imshow(I);title(原图像);improfile%用鼠标选择一条对角线，显示线段的灰度值figure;subplot(121)plot(0:0.01:1,sqrt(0:0.01:1)axis squaretitle(平方根灰度变换函数)subplot(122)maxnum=double(max(max(I);%取得二维数组最大值J=sqrt(double(I)/maxnum);%把数据类型转换成double,然后进行平方根变换%sqrt函数不支持uint8类型J=uint8(J*maxnum);%把数据类型转换成uint8类型imshow(J)title(平方根变换后的图像)3.直方图均衡化程序举例% HISTGRAM EAQUALIZATIONclc;% Clear command windowI=imread(tire.tif);% reads the image in tire.tif into Iimshow(I);% displays the intensity image I with 256 gray levelsfigure;%creates a new figure windowimhist(I);% displays a histogram for the intensity image IJ=histeq(I,64);% transforms the intensity image I,returning J an intensityfigure;%image with 64 discrete levelsimshow(J);figure;imhist(J);J=histeq(I,32);%transforms the intensity image ,returning in % J an intensityfigure;%image with 32 discrete levelsimshow(J);figure;imhist(J);4.直方图规定化程序举例% HISTGRAM REGULIZATIONclc;%Clear command windowI=imread(tire.tif);%reads the image in tire.tif into IJ=histeq(I,32);%transforms the intensity image I,returning in%J an intensity image with 32 discrete levelscounts,x=imhist(J);%displays a histogram for the intensity image IQ=imread(pout.tif);%reads the image in tire.tif into Ifigure;imshow(Q);figure;imhist(Q);M=histeq(Q,counts);%transforms the intensity image Q so that the%histogram of the output image M approximately matches countsfigure;imshow(M);figure;imhist(M);空域滤波增强部分程序1.线性平滑滤波I=imread(eight.tif);J=imnoise(I,salt & pepper,0.02);subplot(221),imshow(I)title(原图像)subplot(222),imshow(J)title(添加椒盐噪声图像)K1=filter2(fspecial(average,3),J)/255;%应用3*3邻域窗口法subplot(223),imshow(K1)title(3x3窗的邻域平均滤波图像)K2=filter2(fspecial(average,7),J)/255;%应用7*7邻域窗口法subplot(224),imshow(K2)title(7x7窗的邻域平均滤波图像)2.中值滤波器MATLAB中的二维中值滤波函数medfit2来进行图像中椒盐躁声的去除%IMAGE NOISE REDUCTION WITH MEDIAN FILTERclc;hood=3;%滤波窗口I,map=imread(eight.tif);imshow(I,map);noisy=imnoise(I,salt & pepper,0.05);figure;imshow(noisy,map);filtered1=medfilt2(noisy,hood hood);figure;imshow(filtered1,map);hood=5;filtered2=medfilt2(noisy,hood hood);figure;imshow(filtered2,map);hood=7;filtered3=medfilt2(noisy,hood hood);figure;imshow(filtered3,map);3. 4邻域8邻域平均滤波算法% IMAGE NOISE REDUCTION WITH MEAN ALGORITHMclc;I,map=imread(eight.tif);noisy=imnoise(I,salt & pepper,0.05);myfilt1=0 1 0;1 1 1;0 1 0;%4邻域平均滤波模版myfilt1=myfilt1/9;%对模版归一化filtered1=filter2(myfilt1,noisy);imshow(filtered1,map);myfilt2=1 1 1;1 1 1;1 1 1;myfilt2=myfilt2/9;filtered2=filter2(myfilt2,noisy);figure;imshow(filtered2,map);频域增强程序举例1.低通滤波器% LOWPASS FILTERclc;I,map=imread(eight.tif);noisy=imnoise(I,gaussian,0.05);imshow(noisy,map);myfilt1=1 1 1;1 1 1;1 1 1;myfilt1=myfilt1/9;filtered1=filter2(myfilt1,noisy);figure;imshow(filtered1,map);myfilt2=1 1 1;1 2 1;1 1 1;myfilt2=myfilt2/10;filtered2=filter2(myfilt2,noisy);figure;imshow(filtered2,map);myfilt3=1 2 1;2 4 2; 1 2 1;myfilt3=filter2(myfilt3,noisy);figure;imshow(filtered3,map);2.布特沃斯低通滤波器图像实例I=imread(saturn.png);J=imnoise(I,salt & pepper,0.02);subplot(121),imshow(J)title(含噪声的原图像)J=double(J);f=fft2(J);g=fftshift(f);M,N=size(f);n=3;d0=20;n1=floor(M/2);n2=floor(N/2);for i=1:M;for j=1:N;d=sqrt(i-n1)2+(j-n2)2);h=1/(1+0.414*(d/d0)(2*n);g(i,j)=h*g(i,j);endendg=ifftshift(g);g=uint8(real(ifft2(g);subplot(122),imshow(g)title(三阶Butterworth滤波图像)色彩增强程序举例1.真彩色增强实例：%真彩色图像的分解clc;RGB=imread(peppers.png);subplot(221),imshow(RGB)title(原始真彩色图像)subplot(222),imshow(RGB(:,:,1)title(真彩色图像的红色分量)subplot(223),imshow(RGB(:,:,2)title(真彩色图像的绿色分量)subplot(224),imshow(RGB(:,:,3)title(真彩色图像的蓝色分量)2.伪彩色增强举例：I=imread(cameraman.tif);imshow(I);X=grayslice(I,16);%thresholds the intensity image I using%threshold values 1/16,2/16,.,15/16,returning an indexed %image in Xfigure;imshow(X,hot(16);3.假彩色增强处理