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目标

  1. 把握线检测
  2. 边缘检测
  3. 应用梯度的分水岭宰割
  4. 管制标记符的分水岭宰割

内容

线检测

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%function B=pixeldup(A, m, n)if nargin<2;    error('At least two inputs are required');endif nargin==2;    n=m;endu=1:size(A,1);m=round(m);u=u(ones(1,m), :);u=u(:);v = 1:size(A,1);n=round(n);v=v(ones(1,n), :);v=v(:);B=A(u,v);%%%%%%%%%%%%%%%%%%%%%%%%%%%%clear allclcf=imread('D:\pic\DIP3E_CH10\Fig1005(a)(wirebond_mask).tif');figure,imshow(f);w=[2 -1 -1;-1 2 -1;-1 -1 2];g=imfilter(double(f),w);figure,imshow(g,[])%fig 2gtop=g(1:120,1:120);gtop=pixeldup(gtop, 4);figure,imshow(gtop,[])%fig 3gbot=g(end-119:end,end-119:end);gbot=pixeldup(gbot,4);figure,imshow(gbot,[])%fig 4g=abs(g);figure,imshow(g,[])%fig 5T=max(g(:));g=g>=T;figure,imshow(g)%fig 6%%%%%%%%%%%%%%%%%%%%%%%%

边缘检测

%%%%%%%%%%%%%%%%%%%%%%%%%%%clear allclcf=imread('D:\pic\DIP3E_CH10\Fig1016(a)(building_original).tif');figure,imshow(f);[gv,t]=edge(f,'sobel','vertical');figure,imshow(gv);tgv=edge(f,'sobel',0.15,'vertical');figure,imshow(gv);gboth=edge(f,'sobel',0.15);figure,imshow(gboth);w45=[-2 -1 0;-1 0 1;0 1 2]g45=imfilter(double(f),w45,'replicate');T=0.3*max(abs(g45(:)));g45=g45>=T;figure,imshow(g45);%%%%%%%%%%%%%%%%%%%%%%%%%Sobel，LoG 和Canny 边缘检测器的比拟clear allclcf=imread('D:\pic\DIP3E_CH10\Fig1016(a)(building_original).tif');figure,imshow(f);[g_sobel_default,ts]=edge(f,'sobel');figure,imshow(g_sobel_default);[g_log_default,tlog]=edge(f,'log');figure,imshow(g_log_default);[g_canny_default,tc]=edge(f,'canny');figure,imshow(g_canny_default);[g_sobel_best,ts]=edge(f,'sobel',0.05);figure,imshow(g_sobel_best);[g_log_best,tlog]=edge(f,'log',0.003,2.25);figure,imshow(g_log_best);[g_canny_best,tc]=edge(f,'canny',[0.04 0.10],1.5);figure,imshow(g_canny_best);

应用梯度的分水岭宰割

clear allclcf=imread('D:\pic\DIP3E_CH10\Fig1057(a)(small_blobs-original).tif');figure,imshow(f);h=fspecial('sobel');fd=double(f);g=sqrt(imfilter(fd,h,'replicate').^2+...    imfilter(fd,h','replicate').^2);figure,imshow(g);L=watershed(g);figure,imshow(L);wr=L==0;g2=imclose(imopen(g,ones(3,3)),ones(3,3));figure,imshow(g2);L2=watershed(g2);figure,imshow(L2);wr2=L2==0;f2=f;f2(wr2)=255;figure,imshow(f2);

管制标记符的分水岭宰割

%%%%%%%%%%%%%%%%了解每幅图像的含意%%%%%%%%%%%clear allclcf=imread('D:\pic\DIP3E_CH10\Fig1057(a)(small_blobs-original).tif');figure,imshow(f);h=fspecial('sobel');fd=double(f);g=sqrt(imfilter(fd,h,'replicate').^2+...imfilter(fd,h','replicate').^2);L=watershed(g);wr=L==0;rm=imregionalmin(g);figure,imshow(rm);im=imextendedmin(f,2);figure,imshow(im);fim=f;fim(im)=175;figure,imshow(fim);Lim=watershed(bwdist(im));figure,imshow(Lim);em=Lim==0;g2=imimposemin(g,im|em);figure,imshow(g2);L2=watershed(g2);figure,imshow(L2);f2=f;f2(L2==0)=255;figure,imshow(f2);

参考文献：

[1] Rafael C. Gonzalez, Richard E. Woods, and Steven L. Eddins. 2003. Digital Image Processing Using MATLAB. Prentice-Hall, Inc., USA.

[2] [阮秋琦. 数字图像处理（MATLAB版）[M]. 北京：电子工业出版社, 2014.](https://github.com/timerring/digital-image-processing-matlab/blob/main/reference/Digital_Image_Processing_(MATLAB_version).pdf)

[3] [冈萨雷斯. 数字图像处理（第三版）[M]. 北京：电子工业出版社, 2011.](https://github.com/timerring/digital-image-processing-matlab/blob/main/reference/Digital_Image_Processing_(Third_Edition).pdf)