[ZF-8670]typo in constant name Zend_Pdf_Image::PING_CHANNEL_RGB_ALPHA

git-svn-id: http://framework.zend.com/svn/framework/standard/trunk@20422 44c647ce-9c0f-0410-b52a-842ac1e357ba

library/Zend/Pdf/FileParser/Image/Png.php

@@ -20,7 +20,7 @@
  * @version    $Id$
  */
 
-/** Zend_Pdf_FileParser_Image */
+/** @see Zend_Pdf_FileParser_Image */
 require_once 'Zend/Pdf/FileParser/Image.php';
 
 
@@ -320,7 +320,7 @@ class Zend_Pdf_FileParser_Image_Png extends Zend_Pdf_FileParser_Image
 
              case Zend_Pdf_Image::PNG_CHANNEL_GRAY_ALPHA:
                   //Fall through to the next case
-             case Zend_Pdf_Image::PING_CHANNEL_RGB_ALPHA:
+             case Zend_Pdf_Image::PNG_CHANNEL_RGB_ALPHA:
                   require_once 'Zend/Pdf/Exception.php';
                   throw new Zend_Pdf_Exception( "tRNS chunk illegal for Alpha Channel Images" );
                   break;