title: BitmapSource access with pointers
body: <p>Is there a way to access the underlying memory of a <code>BitmapImage</code> object with c# pointers?</p>
  
  <p>I know that there's a <code>CopyPixels</code> method but it makes a copy of the pixels array into a new array (duplicating memory requirements). If you open a large image (2gb) it allocates a lot of un-useful stuff. And if you want to operate some sort of elaboration, like CCLA, it takes a huge amount of memory.</p>
  
  <p>I need only to read the pixel array.</p>
  
  <p>Is it possible to address pixels directly like you can do in <code>System.Drawing.Bitmap</code>?</p>
  
  <p>I wrote a fast bitmap access for <code>System.Drawing.Bitmap</code>, but as I'm using WPF, I need the same functionality for <code>BitmapSource</code>. Otherwise I have to duplicate the image loading (Bitmap for my old method and <code>BitmapSource</code> to show the image in WPF) taking a lot of memory and time.</p>
  
  <p>Thank you
  Lorenzo</p>