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Hi guys,

I am using the following code to detect circles

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>

using namespace cv;
using namespace std;

int main()
{
  Mat src, gray;
  src = imread( "/homepath/pic1.png", 1 );resize(src,src,Size(640,480));
  cvtColor( src, gray, COLOR_BGR2GRAY );

  // Reduce the noise so we avoid false circle detection
  GaussianBlur( gray, gray, Size(9, 9), 2, 2 );

  vector<Vec3f> circles;

  // Apply the Hough Transform to find the circles
  HoughCircles( gray, circles, HOUGH_GRADIENT, 1, 30 );

  // 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( src, center, 3, Scalar(0,255,0), -1, 8, 0 );// circle center
      circle( src, center, radius, Scalar(0,0,255), 3, 8, 0 );// circle outline
      cout << "center : " << center << "\nradius : " << radius << endl;
   }

  // Show your results
  namedWindow( "Hough Circle Transform Demo", WINDOW_AUTOSIZE );
  imshow( "Hough Circle Transform Demo", src );

  waitKey(0);
  return 0;
}

However the output look like this:

What am I doing wrong?