WriteableBitmap version

gistfile1.cs

        public static Boundaries CheckBoundaries(WriteableBitmap bmp)
        {
            // check left
            double boundayFactor = 0.1; //10% of the image width/height
            Boundaries b = new Boundaries();
            b.Left = CheckLeft(bmp, boundayFactor);
            b.Right = CheckRight(bmp, boundayFactor);
            b.Top = CheckTop(bmp, boundayFactor);
            b.Bottom = CheckBottom(bmp, boundayFactor);
            return b;
        }

        private static bool CheckLeft(WriteableBitmap bmp, double bf)
        {
            for (int i = 0; i < (int)(bmp.PixelWidth * bf); i++)
            {
                int count = 0;
                for (int j = 0; j < bmp.PixelHeight - 1; j++)
                {
                    if (bmp.GetPixel(i, j) != Color.FromArgb(0, 0, 0, 0))
                    {
                        count++;
                    }
                }
                if (count > 12)
                    return true;
            }
            return false;
        }

        private static bool CheckRight(WriteableBitmap bmp, double bf)
        {
            for (int i = bmp.PixelWidth - 1; i > (int)(bmp.PixelWidth * (1 - bf)); i--)
            {
                int count = 0;
                for (int j = 0; j < bmp.PixelHeight - 1; j++)
                {
                    if (bmp.GetPixel(i, j) != Color.FromArgb(0, 0, 0, 0))
                    {
                        count++;
                    }
                }
                if (count > 12)
                    return true;
            }
            return false;
        }

        private static bool CheckTop(WriteableBitmap bmp, double bf)
        {
            for (int i = 0; i < (int)(bmp.PixelHeight * bf); i++)
            {
                int count = 0;
                for (int j = 0; j < bmp.PixelWidth - 1; j++)
                {
                    if (bmp.GetPixel(j, i) != Color.FromArgb(0, 0, 0, 0))
                    {
                        count++;
                    }
                }
                if (count > 12)
                    return true;
            }
            return false;
        }

        private static bool CheckBottom(WriteableBitmap bmp, double bf)
        {
            for (int i = bmp.PixelHeight - 1; i > (int)(bmp.PixelHeight * (1 - bf)); i--)
            {
                int count = 0;
                for (int j = 0; j < bmp.PixelWidth - 1; j++)
                {
                    if (bmp.GetPixel(j, i) != Color.FromArgb(0, 0, 0, 0))
                    {
                        count++;
                    }
                }
                if (count > 12)
                    return true;
            }
            return false;
        }

        public class Boundaries
        {
            public bool Left { get; set; }
            public bool Right { get; set; }
            public bool Top { get; set; }
            public bool Bottom { get; set; }
        }