automatically cut out objects

x0 = 0;
y0 = 0;
xmax = 0;
ymax = 0;
// GDI+ still lies to us - the return format is BGR, NOT RGB.
BitmapData bmData = EditImage.LockBits(new Rectangle(0, 0, EditImage.Width, EditImage.Height), ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);

int stride = bmData.Stride;
System.IntPtr Scan0 = bmData.Scan0;

unsafe
{
    byte* p = (byte*)(void*)Scan0;
    int nOffset = stride - EditImage.Width * 3;                

    for (int y = 0; y < EditImage.Height; ++y)
    {
        for (int x = 0; x < EditImage.Width; ++x)
        {
            if ((y == 0) && (x == 0))
            {
                awalB = p[0];
                awalG = p[1];
                awalR = p[2];
            }
            else
            {
                if ((awalB == p[0]) && (awalG == p[1]) && (awalR == p[2]))
                {
                }
                else if (x0 == 0)
                {
                    x0 = x;
                }
                else
                {
                    xmax = x;
                }
            }
            p += 3;
        }
        p += nOffset;
    }
}

unsafe
{
    byte* p = (byte*)(void*)Scan0;
    int nOffset = stride - EditImage.Height * 3;

    for (int x = 0; x < EditImage.Width; ++x)
    {
        for (int y = 0; y < EditImage.Height; ++y)
        {
            if ((y == 0) && (x == 0))
            {
                awalB = p[0];
                awalG = p[1];
                awalR = p[2];
            }
            else
            {
                if ((awalB == p[0]) && (awalG == p[1]) && (awalR == p[2]))
                {
                }
                else if (y0 == 0)
                {
                    y0 = y;
                }
                else
                {
                    ymax = y;
                }
            }
            p += 3;
        }
        p += nOffset;
    }
} 

EditImage.UnlockBits(bmData); 

x1 = xmax - x0;
y1 = ymax - y0;
_selection = new Rectangle(new Point(x0, y0), new Size());
_selection.Width = x1;
_selection.Height = y1; 

// Create cropped image:
Image img = pbox_hasil.Image.Crop(_selection);
// Fit image to the picturebox:
pbox_hasil.Image = img.Fit2PictureBox(pbox_hasil);