How to crop circles (found with Hough Transform) in OpenCV?

Question

I\'m using the code from the page. It works very well and I get a circle that I am looking for. All my image have only 1 circle and I have modified parameters of HoughCirc

Answer 1

HoughCircles(src, circles, CV_HOUGH_GRADIENT, 1, parameter_1, parameter_2, parameter_3, parameter_4, parameter_5);

for (size_t i = 0; i < circles.size(); i++)
{
    Point center(cvRound(circles[i][0]), cvRound(circles[i][1]));
    int radius = cvRound(circles[i][2]);
    circleroi = src(Rect(center.x - radius, coordinate
                    center.y - radius, 
                    radius *2,         
                    radius * 2));       
}