学步园

霍夫变换实现直线检测——MATLAB

网上好多不能用，就重新写了一个：

% 入口图像为 BW，出口图像为f
clc,close
BW=imread('D:\picture\9dafa605d53eea243812bb29.jpg');
BW=rgb2gray(BW);
thresh=[0.01,0.17];
sigma=2;%定义高斯参数
f = edge(double(BW),'canny',thresh,sigma);
figure(1),imshow(f,[]);title('canny 边缘检测');
[H, theta, rho]= hough(f, 0.5);
%imshow(theta,rho,H,[],'notruesize'),
axis on,
axis normal
%xlabel('\theta'),ylabel('rho');
[r,c]=houghpeaks(H,5);
hold on
lines=houghlines(f,theta,rho,r,c);
figure,imshow(f,[]),title('Hough Transform Detect Result'),
hold on
for k=1:length(lines) 
    xy=[lines(k).point1;lines(k).point2];
plot(xy(:,1),xy(:,2),'LineWidth',4,'Color',[.6 .6 .6]);
end

Matlab2012版本的内核函数有所改变，houghpeaks, houghlines等函数有所改变，感谢cuicd2011的提醒，R2012a版本的直线检测稍有变化：

clc,close  
BW=imread('D:\picture\9dafa605d53eea243812bb29.jpg');
  
BW=rgb2gray(BW);  
thresh=[0.01,0.17];  
sigma=2;%定义高斯参数  
f = edge(double(BW),'canny',thresh,sigma);  
figure(1),imshow(f,[]);  
title('canny 边缘检测');  
  
[H, theta, rho]= hough(f,'RhoResolution', 0.5);  
%imshow(theta,rho,H,[],'notruesize'),axis on,axis normal  
%xlabel('\theta'),ylabel('rho');  
  
peak=houghpeaks(H,5);  
hold on  
  
lines=houghlines(f,theta,rho,peak);  
figure,imshow(f,[]),title('Hough Transform Detect Result'),hold on  
for k=1:length(lines)  
    xy=[lines(k).point1;lines(k).point2];  
    plot(xy(:,1),xy(:,2),'LineWidth',4,'Color',[.6 .6 .6]);  
end  

实验结果：