/** * @file HoughCircle_Demo.cpp * @brief Demo code for Hough Transform * @author OpenCV team */ #include "opencv2/highgui/highgui.hpp" #include "opencv2/imgproc/imgproc.hpp" #include #include using namespace std; using namespace cv; /** * @function main */ int main(int, char** argv) { Mat src, src_gray; /// Read the image src = imread( argv[1], 1 ); if( !src.data ) { return -1; } /// Convert it to gray cvtColor( src, src_gray, CV_BGR2GRAY ); /// Reduce the noise so we avoid false circle detection GaussianBlur( src_gray, src_gray, Size(9, 9), 2, 2 ); vector circles; /// Apply the Hough Transform to find the circles HoughCircles( src_gray, circles, CV_HOUGH_GRADIENT, 1, src_gray.rows/8, 200, 100, 0, 0 ); /// Draw the circles detected 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]); // circle center circle( src, center, 3, Scalar(0,255,0), -1, 8, 0 ); // circle outline circle( src, center, radius, Scalar(0,0,255), 3, 8, 0 ); } /// Show your results namedWindow( "Hough Circle Transform Demo", CV_WINDOW_AUTOSIZE ); imshow( "Hough Circle Transform Demo", src ); waitKey(0); return 0; }