在上一篇博客中发现经过霍夫变换检测出的直线有可能因为车辆挡住路沿等原因断开,形成线段,这样就不好了,因为检测道路是要找直线焦点。
Thus it is necessary to combine 相同斜率的直线 and connect them.
本代码提供了matlab下求取经过霍夫变换的直线斜率,并将其联合,代码见下方,实验结果见文末。
- % 入口图像为 BW,出口图像为f
- %optimize from main_optimize, merely select 2 lines, one has positive
- %slope,the other has negative slope
- clear all,close all
- BW=imread('D:\Images\NEW\img4b9faef664e03.jpg');
- figure,imshow(BW);
-
- BW=rgb2gray(BW);
- %thresh=[0.01,0.17];
- thresh=[0.01,0.10];
- sigma=2;%定义高斯参数
- f = edge(double(BW),'canny',thresh,sigma);
- figure,subplot(121);
- imshow(f,[]);
- title('canny Edge Detect Result');
-
- [H, theta, rho]= hough(f, 0.1);%cos(theta)*x+sin(theta)*y=rho
- %imshow(theta,rho,H,[],'notruesize'),axis on,axis normal
- %xlabel('\theta'),ylabel('rho');
-
- [r,c]=houghpeaks(H,10);
- hold on
-
-
- lines=houghlines(f,theta,rho,r,c);
-
- subplot(122);
- imshow(f,[]),title('Hough Transform Detect Result'),hold on
- nlind=0;%new line index
- st=1;
- %%%%%%%%%求斜率%%%%%%%%%%%%
- for k=1:length(lines)
- %xy=[lines(k).point1;lines(k).point2];
- xielv(k)=(lines(k).point2(1)-lines(k).point1(1))/(lines(k).point2(2)-lines(k).point1(2)+0.0001)
- end
-
- %%%%%%%%%将相同斜率的直线连起来%%%%%%%%%%%%
- k=1;
- while(k<=length(lines))
- if(k~=length(lines))
- k=k+1;
- end
- while(abs(xielv(k)-xielv(k-1))<0.0001)
- k=k+1;
- if(k>length(lines))
- break;
- end
- end
-
- if(abs(xielv(k-1))<0.05||abs(xielv(k-1))>=10)%eliminate horizontal and vertical lines,防治水平线和楼房
- st=k;
- if(k~=length(lines))
- continue;
- end
- end
-
- if(st==length(lines)&&k==st)
- if(abs(xielv(k))>0.05&&abs(xielv(k))<10)
- nlind=nlind+1;
- newlines(nlind)=lines(st);
- newlines(nlind).point2=lines(k).point2;
- newxy=[newlines(nlind).point1;newlines(nlind).point2];
- plot(newxy(:,2),newxy(:,1),'LineWidth',4,'Color',[.6 1.0 .8]);
- end
- break;
- end
-
- %end=k-1,start=st; draw line
- nlind=nlind+1;
- newlines(nlind)=lines(st);
- newlines(nlind).point2=lines(k-1).point2;
- newxy=[newlines(nlind).point1;newlines(nlind).point2];
- plot(newxy(:,2),newxy(:,1),'LineWidth',4,'Color',[.6 1.0 .8]);
-
- st=k;
- end
-
- fprintf('%d lines are detected in sum.\n',nlind);
实验结果:
原图:
未优化的霍夫变换:
优化后:
本站仅提供存储服务,所有内容均由用户发布,如发现有害或侵权内容,请
点击举报。