Detect color of pixel and click on that pixel in loop

With this code can be detect color of pixel and click on that pixel.

I want to detect color of pixel after click Login button in infinite loop that each time color found program automatically play sound! For example, in an infinite loop or any one second!

And finally, I want this operation to be performed repeatedly.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Threading;
using System.IO;
using System.Media;

namespace Login_Button_Click_for_Puzzle_Pirates
{
    public partial class frmMain : Form
    {
        [DllImport("user32.dll")]
        static extern void mouse_event(uint dwFlags, uint dx, uint dy, uint dwData,
          int dwExtraInfo);


        public enum MouseEventFlags : uint
        {
            LEFTDOWN = 0x00000002,
            LEFTUP = 0x00000004,
            MIDDLEDOWN = 0x00000020,
            MIDDLEUP = 0x00000040,
            MOVE = 0x00000001,
            ABSOLUTE = 0x00008000,
            RIGHTDOWN = 0x00000008,
            RIGHTUP = 0x00000010,
            WHEEL = 0x00000800,
            XDOWN = 0x00000080,
            XUP = 0x00000100
        }

        public frmMain()
        {
            InitializeComponent();
        }

        private void btnLogin_Click(object sender, EventArgs e)
        {


            // takes a snapshot of the screen
            Bitmap bmpScreenshot = Screenshot();

            // makes the background of the form a screenshot of the screen
            this.BackgroundImage = bmpScreenshot;

            // find the login button and check if it exists
            Point location;
            bool success = FindBitmap(Properties.Resources.bmpLogin, bmpScreenshot, out location);

            // check if it found the bitmap
            if (success == false)
            {
                //MessageBox.Show("Couldn't find the login button");
                return;
            }


            // move the mouse to login button
           //Cursor.Position = location;

            System.Media.SoundPlayer player = new System.Media.SoundPlayer();
            player.Stream = Properties.Resources.Alarm;
            player.Play();


            // click
            MouseClick();


            /*
             *     [x] Snapshot of the whole screen
             *     [x] Find the login button and check if it exists
             *     [x] Move the mouse to login button
             *     [ ] Click the login button
             */
        }

        /// <summary>
        /// Simulates a mouse click
        /// </summary>
        private void MouseClick()
        {
            mouse_event((uint)MouseEventFlags.LEFTDOWN, 0, 0, 0, 0);
            Thread.Sleep((new Random()).Next(20, 30));
            mouse_event((uint)MouseEventFlags.LEFTUP, 0, 0, 0, 0);
        }

        /// <summary>
        /// Takes a snapshot of the screen
        /// </summary>
        /// <returns>A snapshot of the screen</returns>
        private Bitmap Screenshot()
        {
            // this is where we will store a snapshot of the screen
            Bitmap bmpScreenshot = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height);


            // creates a graphics object so we can draw the screen in the bitmap (bmpScreenshot)
            Graphics g = Graphics.FromImage(bmpScreenshot);

            // copy from screen into the bitmap we created
            g.CopyFromScreen(0, 0, 0, 0, Screen.PrimaryScreen.Bounds.Size);

            // return the screenshot
            return bmpScreenshot;
        }

        private bool FindBitmap(Bitmap bmpNeedle, Bitmap bmpHaystack, out Point location)
        {
            for(int outerX = 0; outerX < bmpHaystack.Width - bmpNeedle.Width; outerX++)
            {
                for (int outerY = 0; outerY < bmpHaystack.Height - bmpNeedle.Height; outerY++)
                {
                    for (int innerX = 0; innerX < bmpNeedle.Width; innerX++)
                    {
                        for (int innerY = 0; innerY < bmpNeedle.Height; innerY++)
                        {
                            Color cNeedle = bmpNeedle.GetPixel(innerX, innerY);
                            Color cHaystack = bmpHaystack.GetPixel(innerX + outerX, innerY + outerY);

                            if (cNeedle.R != cHaystack.R || cNeedle.G != cHaystack.G || cNeedle.B != cHaystack.B)
                            {
                                goto notFound;
                            }
                        }
                    }
                    location = new Point(outerX, outerY);
                    return true;
                notFound:
                    continue;
                }
            }
            location = Point.Empty;
            return false;
        }

        private void frmMain_Load(object sender, EventArgs e)
        {

        }
    }
}