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Re: PDF accessibility


From: Andrew Kirkpatrick
Date: Feb 12, 2010 9:24AM

To expand on your second paragraph... I generally agree that tagging is a necessary condition for accessibility, but I'd make a small modification to say that for all but the simplest of documents tagging is a necessary condition for accessibility.

Since Reader does do tagging automatically for untagged documents, if you have a very simple document containing just a few paragraphs of plain text (I'm not suggesting that PDF is the best format for this, just that people do this) then the tags that Reader automatically generates will be sufficient. If you have additional structure in the document such as headings, lists, or tables then it is less likely that the tagging heuristic will be sufficient without further author input, and if you have images that need equivalents then you certainly won't get that in the auto-tagging process.

I completely agree that to be certain that authors should provide tagging. I'm raising this point because I often hear people say that without tags a PDF document is completely inaccessible and this is not completely accurate. Few untagged documents will be completely accessible, but similarly few untagged documents will be completely inaccessible. I've seen few cases where an untagged PDF is less accessible to screen reader than a plain text alternative that people often request and usually the PDF offers more access features for screen reader users.


Andrew Kirkpatrick

Senior Product Manager, Accessibility

Adobe Systems


-----Original Message-----
From: <EMAIL REMOVED> [mailto: <EMAIL REMOVED> ] On Behalf Of Monir ElRayes
Sent: Friday, February 12, 2010 8:20 AM
To: 'WebAIM Discussion List'
Subject: Re: [WebAIM] PDF accessibility

Just to clarify the importance of tagging- it is a necessary condition for
accessibility (i.e. untagged documents are inaccessible as screen readers
use the tags to navigate the structure of the document) but not a sufficient
one (i.e. tagged documents can still be inaccessible if the tagging is not
applied correctly -which is quite common- or if some of the other conditions
for accessibility are not met).

When you use the "Add Tags to Document" command in Acrobat, Acrobat will try
to figure out how to structure the tagging for the document. It often
succeeds with simple (linear text) documents but will typically require
additional work to place the tags correctly for more "complex" documents.

Best Regards,

Monir ElRayes
NetCentric Technologies

-----Original Message-----
[mailto: <EMAIL REMOVED> ] On Behalf Of Priti Rohra
Sent: February-12-10 7:39 AM
To: WebAIM Discussion List
Subject: Re: [WebAIM] PDF accessibility

Hi Geof,

Marking the background image of the PDF file in question as an "Artifact" is

similar to specifying an empty alternate text for decorative image on web
page. This will inform the screen reader to skip it and read the textual

With regards to the level of accessibility of the file is concerned, it is
an untagged PDF document--meaning information is not tagged using
appropriate tags, such as headings, lists, paragraphs etc so the screen
reader is identifying the same as a graphic. The screen reader may or may
not read the information correctly i.e. in the right order, as headings, a
list item or even a link.

Hope this makes it clear for you.

Thanks & Regards,
Priti Rohra
Senior Accessibility Consultant
Net Systems Informatics (India) Pvt. Ltd.
Web: www.n-syst.com|www.barrierbreak.com
Blog: www.barrierbreak.com/blog

Please don't print this email unless you really need to. This will preserve
trees on our planet.

----- Original Message -----
From: "Geof Collis" < <EMAIL REMOVED> >
To: "WebAIM Discussion List" < <EMAIL REMOVED> >
Sent: Friday, February 12, 2010 5:55 PM
Subject: Re: [WebAIM] PDF accessibility

> So no ltext needed then?
> What about its level of accessibility?
> I'm hearing the word "graphic" before each item and it appears to be a
> list.
> At 06:36 AM 2/12/2010, you wrote:
>>No, this is decorative and should be an Artifact.
>>Cheers, Karen
>>-----Original Message-----
>>[mailto: <EMAIL REMOVED> ] On Behalf Of Geof Collis
>>Sent: February-11-10 7:31 PM
>>Subject: [WebAIM] PDF accessibility
>>Hi All
>>If a pdf has an image imbedded in the background and text on top does
>>the image need to be described?
>>Here is the pdf in question.
>>Also is this pdf accessible?
>>Accessibility News
>>Accessibility News International