C# Kinect Random a circle's color when it got touched

I would like to make a few circles with default colors and then once they got touched, a new random color will be assigned to those circles. However, the circles will keep changing colors if the kinect players did not take away his hands from the ball. And I would like to make them like this: once the ball get touched, it changes its color, and it will not change to another colors until the next touch by player. Also, it won't random a color when the player's hand is stayed on the ball. And actually I am not sure that the way I random the colors is correct or not. Why the ball will keep changing colors when it is touch? Is there any problem about the looping? using System; using System.Collections.Generic; using System.Linq; using System.Text;

using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

using Microsoft.Kinect;

using KinectWPFEmgu;

using Emgu.CV;
using Emgu.Util;
using Emgu.CV.Structure;
using Emgu.CV.CvEnum;

using System.Drawing;

namespace Ball
{
/// <summary>

/// Interaction logic for MainWindow.xaml

/// </summary>

public partial class MainWindow : Window
{
    private KinectSensor sensor;

    private short[] depthData = null;

    WriteableBitmap depthBitmap;
    WriteableBitmap colorBitmap;

    byte[] depthPixels;
    byte[] colorPixels;

    private Random rnd1 = new Random();
    private Boolean touched = false;

    int count = 0;

    public MainWindow()
    {
        InitializeComponent();
    }

    private void Window_Loaded(object sender, RoutedEventArgs e)
    {
        System.Console.WriteLine("window loaded");

        if (KinectSensor.KinectSensors.Count == 0)
        {
            MessageBox.Show("No Kinects detected");
            Application.Current.Shutdown();
        }

        else
        {
            sensor = KinectSensor.KinectSensors[0];

            if (sensor == null)
            {
                MessageBox.Show("Kinect is not ready to use");
                Application.Current.Shutdown();
            }
        }

        // enable color and depthstream 
        sensor.DepthStream.Enable();
        sensor.ColorStream.Enable();







        depthData = new short[sensor.DepthStream.FramePixelDataLength];



        depthPixels = new byte[sensor.DepthStream.FramePixelDataLength * sizeof(int)];



        colorPixels = new byte[sensor.ColorStream.FramePixelDataLength];







        depthBitmap = new WriteableBitmap(sensor.DepthStream.FrameWidth, sensor.DepthStream.FrameHeight, 96, 96, PixelFormats.Bgr32, null);



        depthImg.Source = depthBitmap;







        colorBitmap = new WriteableBitmap(sensor.ColorStream.FrameWidth, sensor.ColorStream.FrameHeight, 96, 96, PixelFormats.Bgr32, null);



        colorImg.Source = colorBitmap;







        sensor.DepthFrameReady += new EventHandler<DepthImageFrameReadyEventArgs>(sensor_DepthFrameReady);



        sensor.ColorFrameReady += new EventHandler<ColorImageFrameReadyEventArgs>(sensor_ColorFrameReady);







        sensor.Start();



    }









    private void sensor_ColorFrameReady(object sender, ColorImageFrameReadyEventArgs e)
    {



        using (ColorImageFrame colorFrame = e.OpenColorImageFrame())
        {



            if (colorFrame == null) return;







            colorFrame.CopyPixelDataTo(colorPixels);







            colorBitmap.WritePixels(



                new Int32Rect(0, 0, colorFrame.Width, colorFrame.Height),



                colorPixels, colorFrame.Width * 4, 0);



        }



    }







    private void sensor_DepthFrameReady(object sender, DepthImageFrameReadyEventArgs e)
    {



        using (DepthImageFrame depthFrame = e.OpenDepthImageFrame())
        {



            if (depthFrame == null) return;



            depthFrame.CopyPixelDataTo(depthData);







            BitmapSource slicedBmp = depthFrame.SliceDepthImage();



            Image<Bgr, Byte> openCVImg = new Image<Bgr, byte>(slicedBmp.ToBitmap());



            // convert from Bgr to gray 



            Image<Gray, Byte> grayImg = openCVImg.Convert<Gray, Byte>();





            // find all contours with no holes 



            Contour<System.Drawing.Point> contours = grayImg.FindContours(



                Emgu.CV.CvEnum.CHAIN_APPROX_METHOD.CV_CHAIN_APPROX_SIMPLE,



                Emgu.CV.CvEnum.RETR_TYPE.CV_RETR_EXTERNAL



                );



            System.Drawing.Color[] colors = new System.Drawing.Color[4];



            colors[0] = System.Drawing.Color.Red;

            colors[1] = System.Drawing.Color.Green;

            colors[2] = System.Drawing.Color.Blue;

            colors[3] = System.Drawing.Color.Yellow;









            // Ball 1



            //System.Drawing.Color c = colors[rnd1.Next(0,4)];

            System.Drawing.Color c = System.Drawing.Color.Red;



            CircleF cir = new CircleF(new System.Drawing.PointF(50f, 50f), 30);



            openCVImg.Draw(cir, new Bgr(c), 5);



            //Ball 2



            System.Drawing.Color c2 = System.Drawing.Color.Green;



            CircleF cir2 = new CircleF(new System.Drawing.PointF(200f, 200f), 30);



            openCVImg.Draw(cir2, new Bgr(c2), 5);

            while (contours != null)
            {

                // Ball 1

                if (contours.InContour(cir.Center) > 0 && touched == false)
                {
                    c = colors[rnd1.Next(0, 4)];
                    touched = true;

                }

                if (contours.BoundingRectangle.Offset((int)cir.Center.X, (int)cir.Center.Y))
                {
                    touched = false;
                }



                // Ball 2

                if (contours.BoundingRectangle.Contains((int)cir2.Center.X, (int)cir2.Center.Y))
                {

                    c2 = colors[rnd1.Next(0, 4)];



                }


                //if (contours.Area > 10 * 10 && contours.Area < 100 * 100)

                //{








                openCVImg.Draw(contours, new Bgr(System.Drawing.Color.Red), 2);



                //openCVImg.Draw(contours.GetMinAreaRect, new Bgr(System.Drawing.Color.Purple), 2);



                openCVImg.Draw(contours.GetConvexHull(Emgu.CV.CvEnum.ORIENTATION.CV_CLOCKWISE),



                    new Bgr(System.Drawing.Color.Yellow), 2);





                // } 



                contours = contours.HNext;



            }



            openCVImg.Draw(cir, new Bgr(c), 5);
            openCVImg.Draw(cir2, new Bgr(c2), 5);



            // display the processed image to WPF Image control 



            depthImg.Source = ImageHelpers.ToBitmapSource(openCVImg);



        }



    }



}



}