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/**
* @file houghcircles.cpp
* @brief This program demonstrates circle finding with the Hough transform
*/
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/imgproc.hpp"
using namespace cv;
using namespace std;
int main(int argc, char** argv)
{
//![load]
const char* filename = argc >=2 ? argv[1] : "smarties.png";
// Loads an image
Mat src = imread( samples::findFile( filename ), IMREAD_COLOR );
// Check if image is loaded fine
if(src.empty()){
printf(" Error opening image\n");
printf(" Program Arguments: [image_name -- default %s] \n", filename);
return EXIT_FAILURE;
}
//![load]
//![convert_to_gray]
Mat gray;
cvtColor(src, gray, COLOR_BGR2GRAY);
//![convert_to_gray]
//![reduce_noise]
medianBlur(gray, gray, 5);
//![reduce_noise]
//![houghcircles]
vector<Vec3f> circles;
HoughCircles(gray, circles, HOUGH_GRADIENT, 1,
gray.rows/16, // change this value to detect circles with different distances to each other
100, 30, 1, 30 // change the last two parameters
// (min_radius & max_radius) to detect larger circles
);
//![houghcircles]
//![draw]
for( size_t i = 0; i < circles.size(); i++ )
{
Vec3i c = circles[i];
Point center = Point(c[0], c[1]);
// circle center
circle( src, center, 1, Scalar(0,100,100), 3, LINE_AA);
// circle outline
int radius = c[2];
circle( src, center, radius, Scalar(255,0,255), 3, LINE_AA);
}
//![draw]
//![display]
imshow("detected circles", src);
waitKey();
//![display]
return EXIT_SUCCESS;
}
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