title: Getting a CGImage out of a PDF file
body: <p>I have a PDF file where every page is a (LZW) TIFF file. I know this because I created it. I want to be able to load it and save it as a bunch of TIFF files.</p>
  
  <p>I can open the PDF file with CGPDFDocumentCreateWithURL, and get a page. I can even draw the page onto the screen.</p>
  
  <p>What I WANT to do is draw the page into a bitmapContext, so that I can use CGBitmapContextCreateImage to get the image into a CGImageRef. However, in order to create a bitmap context, I need to know the size and resolution of the image. I can't seem to find out how to get either a CGPDFDocument or a CGPDFPage to tell me the resolution of the image object on that page.</p>
  
  <p>Is there an easier way to do this that I'm not realizing?</p>
  
  <p>thanks.</p>