Capture Image from Webcam using Silverlight

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace SilverlightApplication1
{
    public class Imager
    {
        public static ImageTools.ExtendedImage ToImg(WriteableBitmap bitmap)
        {
            ImageTools.ExtendedImage image = new ImageTools.ExtendedImage(bitmap.PixelWidth, bitmap.PixelHeight);

            try
            {
                byte[] pixels = image.Pixels;
                int[] raster = bitmap.Pixels;
                if (raster != null)
                {
                    for (int y = 0; y < image.PixelHeight; y++)
                    {
                        for (int x = 0; x < image.PixelWidth; x++)
                        {
                            int pixelIndex = bitmap.PixelWidth * y + x;
                            int pixel = raster[pixelIndex];
                            byte a = (byte)(pixel >> 24 & 255);
                            float aFactor = (float)a / 255f;
                            if (aFactor > 0f)
                            {
                                byte r = (byte)((float)(pixel >> 16 & 255) / aFactor);
                                byte g = (byte)((float)(pixel >> 8 & 255) / aFactor);
                                byte b = (byte)((float)(pixel & 255) / aFactor);
                                pixels[pixelIndex * 4] = r;
                                pixels[pixelIndex * 4 + 1] = g;
                                pixels[pixelIndex * 4 + 2] = b;
                                pixels[pixelIndex * 4 + 3] = a;
                            }
                        }
                    }
                }
            }
            catch (Exception e)
            {
                throw new ArgumentException("Bitmap cannot accessed", e);
            }
            return image;
        }
    }
}