Hough

#include <opencv2/opencv.hpp>
#include <opencv2/imgproc/imgproc.hpp>

using namespace cv;
using namespace std;

int main( )
{

    Mat srcImage = imread("fore.jpg");
    Mat midImage,dstImage;

    Canny(srcImage, midImage, 50, 200, 3);
    cvtColor(midImage,dstImage, CV_GRAY2BGR);

    vector<Vec2f> lines;
    HoughLines(midImage, lines, 1, CV_PI/180, 150, 0, 0 );


    for( size_t i = 0; i < lines.size(); i++ )
    {
        float rho = lines[i][0], theta = lines[i][1];
        Point pt1, pt2;
        double a = cos(theta), b = sin(theta);
        double x0 = a*rho, y0 = b*rho;
        pt1.x = cvRound(x0 + 1000*(-b));
        pt1.y = cvRound(y0 + 1000*(a));
        pt2.x = cvRound(x0 - 1000*(-b));
        pt2.y = cvRound(y0 - 1000*(a));
        line( dstImage, pt1, pt2, Scalar(55,100,195), 1, CV_AA);
    }

    namedWindow("original image",WINDOW_NORMAL);
    namedWindow("canny",WINDOW_NORMAL);
    namedWindow("hough",WINDOW_NORMAL);
    imshow("original image", srcImage);
    imshow("canny", midImage);

    imshow("hough", dstImage);

    waitKey(0);

    return 0;
}