How to create thread for this object tracking program?

  #include"sstream"
  #include"ostream"
  #include"string"
  #include"opencv2/highgui.hpp"
  #include"opencv2/opencv.hpp"
  #include"stdio.h"

  using namespace cv;
  using namespace std;

  int H_MIN = 0;
  int H_MAX = 256;
  int S_MIN = 0;
  int S_MAX = 256;
  int V_MIN = 0;
  int V_MAX = 256;

  const string windowName1 = "Original image";
  const string windowName2 = "HSV image";
  const string windowName3 = "Thresholded image";
  const string windowName4 = "After Morphological Operations";
  const string trackbarWindowName = "Trackbars";
  const int FRAME_HEIGHT = 480;
  const int FRAME_WIDTH = 640;
  //max number of objects to be detected in frame
  const int MAX_NUM_OBJECTS = 2;
  //minimum and maximum object area
  const int MIN_OBJECT_AREA = 20 * 20;
  const int MAX_OBJECT_AREA = 64 * 48 / 1.5;
  double robotposx, robotposy ;
  void on_trackbar(int, void*)
  {//This function gets called whenever a
  // trackbar position is changed





  }
  string intToString(int number) {


  std::stringstream ss;
  ss << number;
  return ss.str();
  }
  void createTrackbars() {
  //create window for trackbars


  namedWindow(trackbarWindowName, 0);
  //create memory to store trackbar name on window
  char TrackbarName[50];
  sprintf_s(TrackbarName, "H_MIN", H_MIN);
  sprintf_s(TrackbarName, "H_MAX", H_MAX);
  sprintf_s(TrackbarName, "S_MIN", S_MIN);
  sprintf_s(TrackbarName, "S_MAX", S_MAX);
  sprintf_s(TrackbarName, "V_MIN", V_MIN);
  sprintf_s(TrackbarName, "V_MAX", V_MAX);
  //create trackbars and insert them into window
  //3 parameters are: the address of the variable that is changing when the
  trackbar is moved(eg.H_LOW),
  //the max value the trackbar can move (eg. H_HIGH),
  //and the function that is called whenever the trackbar is moved(eg. on_trackbar)
  //                                  ---->    ---->     ---->
  createTrackbar("H_MIN", trackbarWindowName, &H_MIN, H_MAX, on_trackbar);
  createTrackbar("H_MAX", trackbarWindowName, &H_MAX, H_MAX, on_trackbar);
  createTrackbar("S_MIN", trackbarWindowName, &S_MIN, S_MAX, on_trackbar);
  createTrackbar("S_MAX", trackbarWindowName, &S_MAX, S_MAX, on_trackbar);
  createTrackbar("V_MIN", trackbarWindowName, &V_MIN, V_MAX, on_trackbar);
  createTrackbar("V_MAX", trackbarWindowName, &V_MAX, V_MAX, on_trackbar);


  }
  void drawObject(int x, int y, Mat& frame) {

  //use some of the openCV drawing functions to draw crosshairs
  //on your tracked image!

  //added 'if' and 'else' statements to prevent
  //memory errors from writing off the screen (ie. (-25,-25) is not within the
  window!)

  circle(frame, Point(x, y), 20, Scalar(0, 255, 0), 2);
  if (y - 25 > 0)
      line(frame, Point(x, y), Point(x, y - 25), Scalar(0, 255, 0), 2);
  else line(frame, Point(x, y), Point(x, 0), Scalar(0, 255, 0), 2);
  if (y + 25 < FRAME_HEIGHT)
      line(frame, Point(x, y), Point(x, y + 25), Scalar(0, 255, 0), 2);
  else line(frame, Point(x, y), Point(x, FRAME_HEIGHT), Scalar(0, 255, 0), 2);
  if (x - 25 > 0)
      line(frame, Point(x, y), Point(x - 25, y), Scalar(0, 255, 0), 2);
  else line(frame, Point(x, y), Point(0, y), Scalar(0, 255, 0), 2);
  if (x + 25 < FRAME_WIDTH)
      line(frame, Point(x, y), Point(x + 25, y), Scalar(0, 255, 0), 2);
  else line(frame, Point(x, y), Point(FRAME_WIDTH, y), Scalar(0, 255, 0), 2);

  putText(frame, intToString(x) + "," + intToString(y), Point(x, y + 30), 1, 1,
  Scalar(0, 255, 0), 2);

  }
  void morphOps(Mat& thresh) {

  //create structuring element that will be used to "dilate" and "erode" image.
  //the element chosen here is a 3px by 3px rectangle

  Mat erodeElement = getStructuringElement(MORPH_RECT, Size(8, 8));
  //dilate with larger element so make sure object is nicely visible
  Mat dilateElement = getStructuringElement(MORPH_RECT, Size(8, 8));
  erode(thresh, thresh, erodeElement);
  erode(thresh, thresh, erodeElement);
  dilate(thresh, thresh, dilateElement);
  dilate(thresh, thresh, dilateElement);



   }
   void trackFilteredObject(int& x, int& y, Mat threshold, Mat& cameraFeed) {

  Mat temp;
  threshold.copyTo(temp);
  //these two vectors needed for output of findContours
  vector< vector<Point> > contours;
  vector<Vec4i> hierarchy;
  //find contours of filtered image using openCV findContours function
  findContours(temp, contours, hierarchy, cv::RETR_CCOMP, cv::CHAIN_APPROX_SIMPLE);
  //use moments method to find our filtered object
  double refArea = 0;
  bool objectFound = false;
  if (hierarchy.size() > 0) {
  int numObjects = hierarchy.size();
  //if number of objects greater than MAX_NUM_OBJECTS we have a noisy filter
  if (numObjects < MAX_NUM_OBJECTS) {
  for (int index = 0; index >= 0; index = hierarchy[index][0]) {
      Moments moment = moments((cv::Mat)contours[index]);
  double area = moment.m00;
     //if the area is less than 20 px by 20px then it is probably just noise
  //if the area is the same as the 3/2 of the image size, probably just a bad filter
//we only want the object with the largest area so we safe a reference area each
　//iteration and compare it to the area in the next iteration.
  if (area > MIN_OBJECT_AREA && area<MAX_OBJECT_AREA && area>refArea) {
  x = moment.m10 / area;
  y = moment.m01 / area;
  objectFound = true;
  refArea = area;
      }
  else objectFound = false;
      }
  //let user know you found an object
  if (objectFound == true) {
  putText(cameraFeed, "Tracking Object", Point(0, 50), 2, 1, Scalar(0, 255, 0), 2);
  //draw object location on screen
  drawObject(x, y, cameraFeed);
                   }
    }
  else putText(cameraFeed, "TOO MUCH NOISE! ADJUST FILTER", Point(0, 50), 1, 2,
  Scalar(0, 0, 255), 2);
  }
    }
  int main(int argc, char* argv[])
  {
  //some boolean variables for different functionality within this program
  bool trackObjects = true;
  bool useMorphOps = false;
  int iLastX1 = -1;
  int iLastY1 = -1;
  int iLastX2 = -1;
  int iLastY2 = -1;
  //Matrix to store each frame of the webcam feed
  Mat cameraFeed;
  //matrix storage for HSV image
  Mat HSV;
  //matrix storage for binary threshold image
  Mat threshold;
  //x and y values for the location of the object
  int x = 0, y = 0;
  //create slider bars for HSV filtering
  createTrackbars();
  //video capture object to acquire webcam feed
  VideoCapture capture;
  //open capture object at location zero (default location for webcam)
  capture.open(0);
  //set height and width of capture frame
  capture.set(cv::CAP_PROP_FRAME_WIDTH, FRAME_WIDTH);
  capture.set(cv::CAP_PROP_FRAME_HEIGHT, FRAME_HEIGHT);
  Mat imgTmp1;//,imgTmp2;
  capture.read(imgTmp1);
  Mat imgLines1 = Mat::zeros(imgTmp1.size(), CV_8UC3);;
  //Mat imgLines = Mat::zeros(imgTmp1.size(), CV_8UC3);;
  //start an infinite loop where webcam feed is copied to cameraFeed matrix
  //all of our operations will be performed within this loop
  Moments oMoments1 = moments(threshold);
  double d1M01 = oMoments1.m01;
  double d1M10 = oMoments1.m10;
  double d1Area = oMoments1.m00;
  double Xa = 22957,Ya = 17037, xa = 526, ya = 246;
  double Xb = 22957, Yb = 2437, xb = 123, yb = 246;
  double Xd = 12356, Yd = 17037, xd = 590, yd = 0;
  double Xe = 22957, Ye = 9437, xe = 315, ye = 0;

  double aw = -0.260163;
  double bw = 275.0;
  double c = 1057.03;
  double a = -2.70684e-8;
  double b = -6.11588e-4;

  while (1) {
      //store image to matrix
      capture.read(cameraFeed);
      //convert frame from BGR to HSV colorspace
      cvtColor(cameraFeed, HSV, COLOR_BGR2HSV);
      //filter HSV image between values and store filtered image to
      //threshold matrix
  inRange(HSV, Scalar(H_MIN, S_MIN, V_MIN), Scalar(H_MAX, S_MAX, V_MAX), threshold);
  //perform morphological operations on thresholded image to eliminate noise
      //and emphasize the filtered object(s)
      if (useMorphOps)
          morphOps(threshold);
      //pass in thresholded frame to our object tracking function
      //this function will return the x and y coordinates of the
      //filtered object
      if (trackObjects)
          trackFilteredObject(x, y, threshold, cameraFeed);
      Moments oMoments1 = moments(threshold);
      double d1M01 = oMoments1.m01;
      double d1M10 = oMoments1.m10;
      double d1Area = oMoments1.m00;

      if (d1Area > 10000)
      {
          //calculate the position of the ball
          int posX1 = d1M10 / d1Area;
          int posY1 = d1M01 / d1Area;

      if ( posX1 >= 0 && posY1 >= 0)
          {

      /*Draw a red line from the previous point to the current point*/

          robotposx = (1.0 / (posY1 - c) - b) / a;
          robotposy = (posX1 - xe) * (Yd - Ye) / (aw * posY1 + bw) + Ye;
    line(threshold, Point(posX1-10, posY1), Point(posX1+10, posY1), Scalar(255, 0,
    0), 2);
    line(threshold, Point(posX1 , posY1-10), Point(posX1, posY1+10), Scalar(255, 0,
    0), 2);
   }

          iLastX1 = posX1;
          iLastY1 = posY1;
       //Find the Contour of the Object
          vector<vector<cv::Point>> contours;
  findContours(threshold, contours, cv::RETR_CCOMP, cv::CHAIN_APPROX_SIMPLE);
          for (int i = 0; i < contours.size(); i++)
      {
          drawContours(threshold, contours, i, Scalar(255, 0, 0), 2);

          }



          //show frames
          imshow(windowName3, threshold);
          imshow(windowName1, cameraFeed);
          imshow(windowName2, HSV);


          //delay 30ms so that screen can refresh.
          //image will not appear without this waitKey() command
          waitKey(1);
      }
  }





  return 0;
    }

int main(int argc, char* argv[])
		{
			bool trackObjects = true;
			bool useMorphOps = false;
			int iLastX1 = -1;
			int iLastY1 = -1;
			int iLastX2 = -1;
			int iLastY2 = -1;
			Mat cameraFeed;
			Mat HSV;
			//matrix storage for binary threshold image
			Mat threshold;
			//x and y values for the location of the object
			int x = 0, y = 0;
			//create slider bars for HSV filtering
			createTrackbars();
			//video capture object to acquire webcam feed
			VideoCapture capture;
		//open capture object at location zero (default location for webcam)
			capture.open(0);
			//set height and width of capture frame
			capture.set(cv::CAP_PROP_FRAME_WIDTH, FRAME_WIDTH);
			capture.set(cv::CAP_PROP_FRAME_HEIGHT, FRAME_HEIGHT);
			Mat imgTmp1;//,imgTmp2;
			capture.read(imgTmp1);
			Mat imgLines1 = Mat::zeros(imgTmp1.size(), CV_8UC3);;
			//Mat imgLines = Mat::zeros(imgTmp1.size(), CV_8UC3);;
	//start an infinite loop where webcam feed is copied to cameraFeed matrix
	//all of our operations will be performed within this loop
			Moments oMoments1 = moments(threshold);
			double d1M01 = oMoments1.m01;
			double d1M10 = oMoments1.m10;
			double d1Area = oMoments1.m00;
			double Xa = 22957, Ya = 17037, xa = 526, ya = 246;
			double Xb = 22957, Yb = 2437, xb = 123, yb = 246;
			double Xd = 12356, Yd = 17037, xd = 590, yd = 0;
			double Xe = 22957, Ye = 9437, xe = 315, ye = 0;

			double aw = -0.260163;
			double bw = 275.0;
			double c = 1057.03;
			double a = -2.70684e-8;
			double b = -6.11588e-4;


			//store image to matrix
			capture.read(cameraFeed);
			//convert frame from BGR to HSV colorspace
			cvtColor(cameraFeed, HSV, COLOR_BGR2HSV);
			//filter HSV image between values and store filtered image to
			//threshold matrix
    inRange(HSV, Scalar(H_MIN, S_MIN, V_MIN), Scalar(H_MAX, S_MAX, V_MAX), threshold);
	//perform morphological operations on thresholded image to eliminate noise
			//and emphasize the filtered object(s)
			if (useMorphOps)
				morphOps(threshold);
			//pass in thresholded frame to our object tracking function
			//this function will return the x and y coordinates of the
			//filtered object
			if (trackObjects)
				trackFilteredObject(x, y, threshold, cameraFeed);

			if (d1Area > 10000)
			{
				//calculate the position of the ball
				int posX1 = d1M10 / d1Area;
				int posY1 = d1M01 / d1Area;
				//int posX2 = d2M10 / d2Area;
				//int posY2 = d2M01 / d2Area;

				if ( posX1 >= 0 && posY1 >= 0)
				{

		/*Draw a red line from the previous point to the current point*/
		robotposx = (1.0 / (posY1 - c) - b) / a;
		robotposy = (posX1 - xe) * (Yd - Ye) / (aw * posY1 + bw) + Ye;

    line(threshold, Point(posX1 - 10, posY1), Point(posX1 + 10, posY1), Scalar(255, 0, 
    0), 2);
    line(threshold, Point(posX1, posY1 - 10), Point(posX1, posY1 + 10), Scalar(255, 0, 
    0), 2);
					}
      iLastX1 = posX1;
      iLastY1 = posY1;
				//Find the Contour of the Object
				vector<vector<cv::Point> > balls;
				vector<cv::Rect> ballsBox;
				vector<vector<cv::Point>> contours;
	findContours(threshold, contours, cv::RETR_CCOMP, cv::CHAIN_APPROX_SIMPLE);
	std::thread t1([&]() {
		for (int i = 0; i < contours.size(); i++)
			{
		drawContours(threshold, contours, i, Scalar(255, 0, 0), 2);
	        cv::Rect bBox;
		bBox = cv::boundingRect(contours[i]);
                float ratio = (float)bBox.width / (float)bBox.height;
		if (ratio > 1.0f)
		ratio = 1.0f / ratio;
                // Searching for a bBox almost square
		if (ratio > 0.75 && bBox.area() >= 400)
		    {
			balls.push_back(contours[i]);
			ballsBox.push_back(bBox);
		    }
                    cv::Point center;
		    center.x = ballsBox[i].x + ballsBox[i].width / 2;
		    center.y = ballsBox[i].y + ballsBox[i].height / 2;
		    cv::circle(threshold, center, 2, CV_RGB(20, 150, 20), -1);
                    stringstream sstr;
		    sstr << "(" << center.x << "," << center.y << ")";
		    cv::putText(threshold, sstr.str(),
		    cv::Point(center.x + 3, center.y - 3),
		    cv::FONT_HERSHEY_SIMPLEX, 0.5, CV_RGB(20, 150, 20), 2);
					}
					});
		    t1.join();
				//show frames 
				imshow(windowName3, threshold);
				imshow(windowName1, cameraFeed);
				imshow(windowName2, HSV);
                    //delay 30ms so that screen can refresh.
		    //image will not appear without this waitKey() command
		    waitKey(10);
			}