Win8Metro(C#)数字图像处理--2.29图像除法运算

/// <summary>
        /// Division of two images.
        /// </summary>
        /// <param name="src">The frist source image.</param>
        /// <param name="divSrc">The second source image.</param>
        /// <returns></returns>
        public static WriteableBitmap DivisionProcess(WriteableBitmap src,WriteableBitmap divSrc)////29图像除法
        {
            if (src != null)
            {
                int w = src.PixelWidth;
                int h = src.PixelHeight;
                WriteableBitmap divImage = new WriteableBitmap(w, h);
                byte[] temp = src.PixelBuffer.ToArray();
                byte[] divTemp = divSrc.PixelBuffer.ToArray();
                byte[] dst = new byte[w * h * 4];
                int r = 0, g = 0, b = 0, graySrc = 0, grayDiv = 0;
                for (int i = 0; i < w; i++)
                {
                    for (int j = 0; j < h; j++)
                    {
                        graySrc = temp[i * 4 + (h - 1 - j) * w * 4] + temp[i * 4 + 1 + (h - 1 - j) * w * 4] + temp[i * 4 + 2 + (h - 1 - j) * w * 4];
                        grayDiv = divTemp[i * 4 + (h - 1 - j) * w * 4] + divTemp[i * 4 + 1 + (h - 1 - j) * w * 4] + divTemp[i * 4 + 2 + (h - 1 - j) * w * 4];
                        if (grayDiv + graySrc != 0)
                        {
                            b = temp[i * 4 + (h - 1 - j) * w * 4] * (temp[i * 4 + (h - 1 - j) * w * 4] - divTemp[i * 4 + (h - 1 - j) * w * 4]) / (temp[i * 4 + (h - 1 - j) * w * 4] + divTemp[i * 4 + (h - 1 - j) * w * 4]);
                            g = temp[i * 4 + 1 + (h - 1 - j) * w * 4] * (temp[i * 4 + 1 + (h - 1 - j) * w * 4] - divTemp[i * 4 + 1 + (h - 1 - j) * w * 4]) / (temp[i * 4 + 1 + (h - 1 - j) * w * 4] + divTemp[i * 4 + 1 + (h - 1 - j) * w * 4]);
                            r = temp[i * 4 + 2 + (h - 1 - j) * w * 4] * (temp[i * 4 + 2 + (h - 1 - j) * w * 4] - divTemp[i * 4 + 2 + (h - 1 - j) * w * 4]) / (temp[i * 4 + 2 + (h - 1 - j) * w * 4] + divTemp[i * 4 + 2 + (h - 1 - j) * w * 4]);
                            dst[i * 4 + j * w * 4] = (byte)(b > 0 ? (b < 255 ? b : 255) : 0);
                            dst[i * 4 + 1 + j * w * 4] = (byte)(g > 0 ? (g < 255 ? g : 255) : 0);
                            dst[i * 4 + 2 + j * w * 4] = (byte)(r > 0 ? (r < 255 ? r : 255) : 0);
                            dst[i * 4 + 3 + j * w * 4] = 0;
                            b = 0; g = 0; r = 0;
                        }
                    }
                }
                Stream sTemp = divImage.PixelBuffer.AsStream();
                sTemp.Seek(0, SeekOrigin.Begin);
                sTemp.Write(dst, 0, w * 4 * h);
                return divImage;
            }
            else
            {
                return null;
            }      
        }