（原）opencv直线拟合fitLine

转载请注明出处

http://www.cnblogs.com/darkknightzh/p/5486234.html

参考网址：

http://blog.csdn.net/thefutureisour/article/details/7599537

 Mat img(, , CV_8UC1, Scalar());
     std::vector<Point2f> points;
     points.push_back(Point2f(10.5, 10.2));
     points.push_back(Point2f(20.6, 20.7));
     points.push_back(Point2f(33.5, 30.2));
     points.push_back(Point2f(40.7, ));

     //储存拟合直线的容器
     Vec4f line;
     //直线拟合函数
     fitLine(Mat(points), line, CV_DIST_L1, , 0.01, 0.01);
     std::cout << "line: (" << line[] << "," << line[] << ")(" << line[] << "," << line[] << ")\n";

     for (auto i = ; i < points.size(); i++)
         cv::circle(img, cvPoint(points.at(i).x, points.at(i).y), , Scalar());

     double k = line[] / line[];
     double step = ;
     cv::line(img, cvPoint(line[] - step, line[] - k*step), cvPoint(line[] + step, k*step + line[]), Scalar());

     imshow("img", img);
     waitKey();

拟合的结果Vec4f类型的line中的前两个值 给出的是直线的方向的单位向量，后两个值给出的是该直线通过的一个点（转自参考网址）。