Link to home
Start Free TrialLog in
Avatar of raeben
raeben

asked on

Acrobat Tagging for Accessibility (screen readers; Section 508 )

I've been tagging PDF files for accessibility (Section 508 of the ADA) for over a year.  I've encountered all sorts of problems, and found work arounds for a number of them.  But I have found NO source of advice or information other than the various Adobe documents, all of which I have read and reread. But they didn't help much beyond the basics.

Many times we are just handed a PDF file and asked to make it accessible -- there is no opportunity to recreate the document in a program that was designed to be compatible with Acrobat or 508-friendly.   Using the "make accessible" feature does not always yield results we can use without manual tagging.

Manual tagging may go smoothly or it may not. Sometimes an entire page will refuse to be tagged. Sometimes when an object is tagged an "incorrect PDE object" error message will pop-up.  Sometimes when text is manually tagged it will "drop out" of the PDF itself, sometimes it can be found underneath other objects on the page, sometimes not, Any information on these sort of problems would be very helpful.

My latest and greatest problem was with a number 1-page documents created in Word 2000, with heavy graphics, shading and 2-column format text.  I tagged 10 such files using a combination of manual and automatic tagging. I had very little problems, I seriously thought things were going quite well!  But when I took then to another machine to read them, only 4 would read. Six of them generated a "MSAA tags not present" error. I have never seen this error before. The files could not be resaved on the other machine.  Both Acrobat and Jaws crashed in a couple of cases.  We prefer to keep our screen reader, Jaws 4.5, on a separate machine because it has it's own display driver which causes problems on our other machines, which we use for page layout and word processing as well as 508ing.  These PDFs were tagged in Acrobat 5.05 on a Windows NT machine. They are being read on a Windows 2000 machine.  We have Acrobat 6.0 installed but I found it problematic with these particular files because I could not click on and select graphic elements. They were selectable in 5.5 without a problem.

We have active and updated virus protection on all machines.

Any ideas?

Rae Benedetto
Avatar of antonieraj
antonieraj

Hi

I use Accessibility & Tagging options for
Conversion of PDF to RTF for Freeflow of Multiple Column text and
Comparision of PDF Files

I usually face the problem of "Some unknown font encoding encountered." Errors. As Acrobat donot recognise some special character in pdf it keep it as Images.

Regarding your Issue

"Incorrect PDEobject": This will pop-up if there is Hugh Number of pages with images and Your trying to insert pages or Data.

"MSAA tags not present": MSAA[Microsoft® Active Accessibility]
MSAA Doesnot support MAC version Acrobat only support windows version.

'From Adobe site'-

"Provides direct support for screen readers via the Microsoft Active Accessibility (MSAA) application programming interface (API) for the Windows® platform. MSAA lets Acrobat 5.0 integrate with assistive technology products including newer versions of screen readers from vendors such as Freedom Scientific and GW Micro"

I think Alternate text or information for MSAA tag is not present in your Document


I have going through some site which are useful for Me. Kindly check them if needed

www.htctu.fhda.edu/trainings/manuals/web/Creating_Accessible_PDFs.pdf

http://www.adobe.com/products/acrobat/acrobat_508.html

http://www.adobe.com/products/acrobat/access_booklet.html

http://www.adobe.com/products/acrobat/access_faq.html#11

Accessibility Information at Adobe
http://access.adobe.com

Accessibility Information and Support

Acrobat Accessibility Resources
http://www.adobe.com/products/acrobat/solutionsacc.html

On-Line Conversion Tools
http://www.adobe.com/products/acrobat/access_onlinetools.html

How to Create Accessible PDF Documents
http://www.adobe.com/products/acrobat/access_booklet.html

Advanced Techniques for Creating Accessible PDF Documents
http://access.adobe.com/information.html
The message about the incorrect PDE object suggests that there is something seriously wrong with the PDF file. PDE objects are things like text, images, fonts, ... The error would be generated if e.g. the software is expecting to work with text, but is actually working on an image. Somehow Acrobat got confused about it's own data. When this happens, the file is corrupt, and therefore can no longer be saved by Acrobat.

Is there anything special about the Word documents? You could try to remove the shadings from your files, and recreate the PDF documents. If this still fails, remove the graphics and recreate them. Text only should not cause any problems, but who knows ...

Once you know which elements cause the problems, you can try to see if there are any PDFMaker options that change the behavior of these elements.
... one more question: How were the Word files converted to PDF? Usually you an see this in the document information fields.
Avatar of raeben

ASKER

The PDFs were created using Distiller.  

The problem seemed to resolve itself when I regrouped some of the tags involved with the Charts. Once I did that everything was fine. The strange part is that in at least 2 of the files, these tag items were organized the same way as in the others but it didn't cause any problem.  There is obviously something going on here that is not apparent.. perhaps it has something to do with tag structure definitions or rules (such definitions/rules that have not been spelled out in any Adobe document I can find) or there is something going on the machine in question -- a memory problem or system incompatibilty.

The thing is, we can't remove the shadings from the finals, although that would be a good problem solving method to see what is causing the problem.

Thanks for your help.
I did not mean that you should remove the items form the final documents: Just as a debug tool to find out why things are acting up.

The chapter 10.7 in the PDF Reference, version 1.5 does contain the description of the tag format, 10.8 talks about "Accessibility Support". This may not be the right document for you: It's the reference manual that describes the low level stuff that's in the guts of a PDF document. It's heavy stuff, and you need same familiarity with the first 10 chapters of the document in order to understand this information.
Avatar of raeben

ASKER

Yes, that would be a good debug.  

I believe I looked at the PDF Reference at one point. That's the document aimed at developers, right?  It had some interesting information, but was not ultlimately useful for tagging because that's really not what it's about.  Maybe if I was a programmer, but I'm not.

I've had numerous problems with tagging PDFs.  

Sometimes, many times,  they tag very easily and smoothly.

And other times, for no apparent reason a whole page will just refuse to be read by the screen reader-- I believe the response from Jaws is " Your document appears to be be blank or have malformed structure.  "  or something to that effect. I've had it do that to a single page in a multipage document -- all text on the page, no graphics. **Literally nothing** was apparently wrong on viewing the page.  I eventually worked around this by recreating the page separately, retagging it and inserted it in the finished PDF.

One can't look below the surface to see how the Acrobat is really structuring things to get a hint at what's causing these problems.  At least I can't. Perhaps it's some code in the parent program -- Word, or Quark, whatever created the pdf -- that's causing the problem.  But again, those codes are invisible to the end user.  

And the goal here is creating a workable, readable PDF, not figuring out how everything works!  

Thanks for the input.

Unfortunately sometimes it is necessary to dive deep into the guts of PDF in order to make something workable or readable. But this is not the topic of this thread.

Have you tried the new Acrobat 6 "Read Out Loud" feature with your faulty PDF documents?
ASKER CERTIFIED SOLUTION
Avatar of Karl Heinz Kremer
Karl Heinz Kremer
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
SOLUTION
Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial