Color.cs

[DllImport("user32.dll", SetLastError = true)]
private static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll", SetLastError = true)]
private static extern IntPtr GetWindowDC(IntPtr window);
[DllImport("gdi32.dll", SetLastError = true)]
private static extern uint GetPixel(IntPtr dc, int x, int y);
[DllImport("user32.dll", SetLastError = true)]
private static extern int ReleaseDC(IntPtr window, IntPtr dc);

private static Color GetColor(string x, string y)
{
	return GetColor(Convert.ToInt32(x), Convert.ToInt32(y));
}

private static Color GetColor(int x, int y)
{
	IntPtr desk = GetDesktopWindow();
	IntPtr dc = GetWindowDC(desk);
	int a = (int)GetPixel(dc, x, y);
	ReleaseDC(desk, dc);
	return Color.FromArgb(255, (a >> 0) & 0xff, (a >> 8) & 0xff, (a >> 16) & 0xff);
}

private void SearchPixel(string hexcode = "#BD20B1", int xspixel = 0, int xepixel = 1920, int yspixel = 0, int yepixel = 1080)
{
	int hexCount = 0;

	Color desiredPixelColor = ColorTranslator.FromHtml(hexcode);

	Parallel.For(xspixel, xepixel, (x, xstate) =>
	{
		Parallel.For(yspixel, yepixel, (y, ystate) =>
		{
			Color currentPixelColor = GetColor(x, y);

			if (desiredPixelColor == currentPixelColor)
			{
				hexCount++;
				LblToplamHex.Content = hexCount.ToString();
			}
		});
	});

	LblToplamHex.Content += " - End..";
}