title: Transparent images in PDF
body: <p><a href="http://orderingplatform.com/files/temp/testpdf.pdf" rel="nofollow noreferrer">This PDF</a> is composed of several source pieces. Five of them are PNGs containing an alpha channel. One is a PNG with no alpha channel. And the last piece is a Photoshop PDF with transparency effects.  The pieces were assembled using ABCpdf 9.1.</p>
  
  <p>On Acrobat 9, Foxit Reader, and Chrome's in-browser PDF viewer, these display correctly, with the Photoshop background showing through the transparent part of the alpha channel PNGs, and the non-alpha PNG showing through the center of the Photoshop image.</p>
  
  <p><img src="https://i.stack.imgur.com/DA1ja.jpg" alt="correct display"></p>
  
  <p>On Acrobat X or Acrobat XI, anything that is meant to be a transparent area is instead solid white. If Edit/Preferences/Page Display/Show transparency grid is checked, then the solid white becomes the gray checkerboard.  But the background never shows through.</p>
  
  <p><img src="https://content.screencast.com/users/twymore/folders/Jing/media/1f34a1e0-2acb-4864-b1ef-86f788740038/2014-03-03_1246.png" alt="incorrect display"></p>
  
  <p><strong>(Yes, these screenshots are of different PDFs, and both are different from the PDF linked above. But the transparency problem affects all of them.)</strong></p>
  
  <p>Does anyone know why it would be doing this? Did we construct it wrong?</p>