Here is my code: 
 
include <iostream>
 
include <time.h>
 
include <stdio.h>
 
include <raspicam raspicam_cv.h="">
 
include <raspicam raspicam.h="">
 
include <opencv2 opencv.hpp="">
 
include <opencv2 core="" core.hpp="">
 
include <opencv2 highgui="" highgui.hpp="">
 
include "opencv2/features2d/features2d.hpp"
 
include "opencv2/nonfree/features2d.hpp"
 
include <cstdlib>
 
include <fstream>
 
include <string>
 
include <sstream>
 
include <opencv2 stitching="" stitcher.hpp="">
 
include "camera.h"
 
include <pthread.h>
 

#include <iostream>
#include <time.h>
#include <stdio.h>
#include <raspicam/raspicam_cv.h>
#include <raspicam/raspicam.h>
#include <opencv2/opencv.hpp>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include "opencv2/features2d/features2d.hpp"
#include "opencv2/nonfree/features2d.hpp"
#include <cstdlib>
#include <fstream>
#include <string>
#include <sstream>
#include <opencv2/stitching/stitcher.hpp>
#include "camera.h"
#include <pthread.h>
using namespace std;
using namespace cv;
 
cv;
Mat dst;
 
dst;
int main(int argc,char **argv)
{
time_t start,end;
Mat template1 = imread( "100_1.jpg");//, CV_LOAD_IMAGE_GRAYSCALE ); //loading object to be detectedimg_object
Mat template2 = imread( "NoEntry.jpg");
Mat template3 = imread( "Speed80.png");
 
"Speed80.png");
raspicam::RaspiCam_Cv Camera;
 OpenPiCamera(Camera);
 
 cv::Mat rawMat;
IplImage *frame;
 
*frame;
cvNamedWindow("Capture Frame",1);
 time(&start);
 int counter=0;
 while(1)
 {
 //if(counter%5==0)
 {
 Camera.grab();
 Camera.retrieve(rawMat);
  Mat img_scene=rawMat.clone();
 cvtColor(rawMat,rawMat,CV_RGB2HSV);
  cv::Scalar min(220/2, 0, 0);
 cv::Scalar max(260/2,255, 255);
 inRange(rawMat,min,max,dst);
  vector<cv::Vec3f> circles;
  HoughCircles( blur, circles, CV_HOUGH_GRADIENT,1,dst.rows/4,70, 20, 1, 40);//3, 5,400, 10, 0, 80 1, img_scene.rows/6, 100,70,0, 50 dst.rows/8
 cv::Rect borders(Point(0,0), dst.size());
 
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]);
cv::circle( dst, center, 3, Scalar(255,255,255), -1);
cv::circle( dst, center, radius, Scalar(255,255,255), 1 );
imshow("hough",dst);
 
imshow("hough",dst);
 int x=cvRound(circles[i][0])-cvRound(circles[i][2]);
 int y=cvRound(circles[i][1])-cvRound(circles[i][2]);
 Rect r(abs(x),abs(y),radius*2,radius*2);
 if(r.area()>100)
 {
  Mat roi( radius*2, radius*2, CV_8UC1);
 roi=img_scene( Rect(abs(x),abs(y),radius*2,radius*2)& borders);//save ROI
 Mat mask( roi.size(),roi.type(),Scalar::all(0));
 circle(mask,Point(radius,radius),radius,Scalar::all(255),-1);//circle(mask,Point(radius,radius),radius,Scalar::all(255),-1);
  Mat roi_cropped=roi & mask;
 int W=0,H=0;
 W=dst.cols;
 H=dst.rows;
  int w=0,h=0;
 w=roi_cropped.cols;
 h=roi_cropped.rows;
  Mat res_32f1(W - w + 1, H - h + 1, CV_32FC3);
 Mat res_32f2(W - w + 1, H - h + 1, CV_32FC3);
 Mat res_32f3(W - w + 1, H - h + 1, CV_32FC3);
 Mat resizedTemplate1,resizedTemplate2,resizedTemplate3;
 //resizedTemplate1=template1.clone();
  resize(template1, resizedTemplate1, roi_cropped.size());//resizing template into ROI
 resize(template2, resizedTemplate2, roi_cropped.size());
 resize(template3, resizedTemplate3, roi_cropped.size());
  matchTemplate(resizedTemplate1, roi_cropped, res_32f1, CV_TM_CCORR_NORMED);
 matchTemplate(resizedTemplate2, roi_cropped, res_32f2, CV_TM_CCORR_NORMED);
 matchTemplate(resizedTemplate3, roi_cropped, res_32f3, CV_TM_CCORR_NORMED);
  double minval1, maxval1, minval2, maxval2,minval3, maxval3, minval4, maxval4,minval5, maxval5,threshold1 = 0.74;//.78
 Point minloc1, maxloc1, minloc2, maxloc2,minloc3, maxloc3,minloc4, maxloc4,minloc5, maxloc5;
 minMaxLoc(res_32f1, &minval1, &maxval1, &minloc1, &maxloc1);
 minMaxLoc(res_32f2, &minval2, &maxval2, &minloc2, &maxloc2);
 minMaxLoc(res_32f3, &minval3, &maxval3, &minloc3, &maxloc3);
 double maxInddex;
  double init[]={maxval1, maxval2,maxval3};//,maxval4,maxval5
 valarray<double> myvalarray (init,3);
 double max=(double)myvalarray.max();
  if (max >= threshold1)
 {
  if(max==maxval1)rectangle(img_scene, Point(abs(x),abs(y)),Point(abs(x)+radius*2,abs(y)+radius*2), Scalar(255,255,255), 5, 8, 0);
  if(max==maxval2)rectangle(img_scene, Point(abs(x),abs(y)),Point(abs(x)+radius*2,abs(y)+radius*2), Scalar(255,0,255), 5, 8, 0);
 if(max==maxval3)rectangle(img_scene, Point(abs(x),abs(y)),Point(abs(x)+radius*2,abs(y)+radius*2), Scalar(0,255,255), 5, 8, 0);
 }
 }
 }
 
imshow("Circle",img_scene);
 
imshow("Circle",img_scene);
 frame=new IplImage(rawMat);//
 }
 time(&end);
 ++counter;
  double sec=difftime(end,start);
 cout<<"millisec"<<sec/CLOCKS_PER_SEC*1000;
 cout<<"seconds"<<sec;
  double fps=counter/sec;
 printf("FPS: %0.2f\n",fps);
 cvShowImage("Capture Frame",frame);
  if((cvWaitKey(1) & 255) == 27 ) break;
 }
 ClosePiCamera(Camera);
 
}
 
}
While running the above code, the result is displayed very slowly. Is there any way I can improve the above code to make it more real time? To improve the performance I tried using pthreads.
 pthreads.