code

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

using namespace cv;
using namespace std;
int hi = 1, lo = 1;


void detect1(Mat src)
{
  Mat  src_gray;



  /// 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<Vec3f> 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 );
   HoughCircles(src_gray, circles, CV_HOUGH_GRADIENT, 1, 10,
                 100, 30, 30, 150 // change the last two parameters
                                // (min_radius & max_radius) to detect larger circles
                 );

  /// 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

  imshow( "Hough Circle Transform Demo", src );

  waitKey(0);

}

int main( int argc, char** argv ){

	VideoCapture cap("http://192.168.1.123:8080/video?x.mjpeg"); //capture the video from web cam
	waitKey(5000);

    if ( !cap.isOpened() )  // if not success, exit program
    {
         cout << "Cannot open the web cam" << endl;
         return -1;
    }

	namedWindow("Original", CV_WINDOW_AUTOSIZE); //create a window called "Control"
	  namedWindow( "Hough Circle Transform Demo", CV_WINDOW_AUTOSIZE );



	while (true)
    {
        Mat imgOriginal;

        bool bSuccess = cap.read(imgOriginal); // read a new frame from video

         if (!bSuccess) //if not success, break loop
        {
             cout << "Cannot read a frame from video stream" << endl;
             break;
        }

		 Mat src =imgOriginal;


Mat  src_gray;



  /// 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<Vec3f> circles;

  /// Apply the Hough Transform to find the circles
 // HoughCircles( src_gray, circles, CV_HOUGH_GRADIENT, 1, src_gray.rows/8, 10, 100,300, 1000 );
 //  HoughCircles(src_gray, circles, CV_HOUGH_GRADIENT, 1, 10,100, 30, 30, 150);
  HoughCircles(src_gray, circles, CV_HOUGH_GRADIENT,2,src_gray.rows/4,100,50,5,400);


  /// 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

  imshow( "Hough Circle Transform Demo", src );
  imshow("Original", imgOriginal); //show the original image



        if (waitKey(30) == 27) //wait for 'esc' key press for 30ms. If 'esc' key is pressed, break loop
       {
            cout << "esc key is pressed by user" << endl;
            break;
       }
    }


}