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Topic: RE: PDF Scanner for Accessibility (Via Email)
Conf: (P-PDF) PDF Accessibility, Msg: 134084
From: Duff_Johnson
Date: 6/8/2005 04:25 AM

> Hi, I'm new here. I am wondering if anyone knows of a PDF
> scanner that can search through a directory and scan PDFs to
> check them from Accessibility. I work at a university and we
> are working on being Section 508 compliant and we need a way
> of checking PDFs we have on our webservers.

There is currently no automated way to ensure that any given PDF is
compliant with Section 508.

There is a very common misperception that a clean bill of health from
Acrobat's Accessibility Checker means your file is 508 complaint. This
is emphatically not the case.

The Accessibility Checker in Adobe Acrobat does NOT, repeat does NOT
check for compliance with Section 508. Adobe doesn't claim in any way,
shape or form that the tool does this, and I can assure you that it does
not.

However, the Checker does have SOME limited value in helping to
ascertain which files definitely don't comply (which is almost all of
them, by the way). But this help is VERY limited, and usually
misleading besides.

For example, the Checker will tell you when a PDF includes images
without corresponding alt. text. Very good, PDFs containing images
without alt. text are generally thought to be non-compliant.

However, the number of images in a given PDF is more or less arbitrary
compared to the intent of the author, and has nothing to do with the
number of actual content images present in the document.

Charts and graphs, for example, often include dozens or more of little
tiny images, one for every element in the graphic... lines and such.
Should each of these get alt. text? Of course not - that's absurd.
Generally, the entire chart gets 1 piece of alt. text, or two or three,
depending upon the way the content works... not upon the number of
images!

So, in a file that the Checker says is broken, an
accessibility-enhancement operator may have actually created alt. text
to all PERTINENT images, leaving purely cosmetic images out of the
structure tree (untagged). As a usability matter, the user should not
be forced to hear "Image: page footer graphic including XYZ's address
and phone number" (for example) over and over again on every page.

You can (I hope) see the problem.

That's why people who know what they are doing actually decide NOT to
add alt. text to "every image" on purpose, and yet they can still ensure
a Section 508 compliant - and more important, highly usable - PDF file.

Companies such as my own can conduct audits
of PDF content to determine the current state of accessibility, as well
as execute the compliance and certification (if needed) work to make
sure all files comply.

Duff Johnson
Document Solutions, Inc.
http://www.document-solutions.com