#include "opencv2/highgui/highgui.hpp"

 #include "opencv2/imgproc/imgproc.hpp"

 #include <iostream>

 using namespace cv;

 using namespace std;

 void help()

 {

  cout << "\nThis program demonstrates line finding with the Hough transform.\n"

          "Usage:\n"

          "./houghlines <image_name>, Default is pic1.jpg\n" << endl;

 }

 int main(int argc, char** argv)

 {

  const char* filename = argc >=  ? argv[] : "pic1.jpg";

  Mat src = imread(filename, );

  if(src.empty())

  {

      help();

      cout << "can not open " << filename << endl;

      return -;

  }

  Mat dst, cdst;

  Canny(src, dst, , , );

  cvtColor(dst, cdst, CV_GRAY2BGR);

  #if 0

   vector<Vec2f> lines;

   HoughLines(dst, lines, , CV_PI/, , ,  );

   for( size_t i = ; i < lines.size(); i++ )

   {

      float rho = lines[i][], theta = lines[i][];

      Point pt1, pt2;

      double a = cos(theta), b = sin(theta);

      double x0 = a*rho, y0 = b*rho;

      pt1.x = cvRound(x0 + *(-b));

      pt1.y = cvRound(y0 + *(a));

      pt2.x = cvRound(x0 - *(-b));

      pt2.y = cvRound(y0 - *(a));

      line( cdst, pt1, pt2, Scalar(,,), , CV_AA);

   }

  #else

   vector<Vec4i> lines;

   HoughLinesP(dst, lines, , CV_PI/, , ,  );

   for( size_t i = ; i < lines.size(); i++ )

   {

     Vec4i l = lines[i];

     line( cdst, Point(l[], l[]), Point(l[], l[]), Scalar(,,), , CV_AA);

   }

  #endif

  imshow("source", src);

  imshow("detected lines", cdst);

  waitKey();

  return ;

 }