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Re: PDF/A accessibility

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From: Duff Johnson
Date: Aug 9, 2011 3:18PM

On Aug 9, 2011, at 4:45 PM, Ron Stewart wrote:

> My apologies, but to purport a standard to be accessible when basic elements
> of accessibility are not present is to be disingenuous.

Before you go to "disingenuous" (that's fightin' words, sir) I think it would be best if we agreed on what we're talking about first, no?

> I think I have
> presented the issues clearly, what about reading order in PDF documents

What about reading order? PDF/UA specifies that the content of conforming documents shall be tagged in correct logical reading order. It also specifies that conforming PDF viewers shall be able to make use of that logical structure.

If you are referring to content reading order (ie the order of objects in the content stream), that has to do with "painting" text, graphics, etc. on the page, and is not related to accessibility (which is why PDF/UA ignores the subject). "Reading order" in this context refers to the order in which the computer processes the file... not the end-user.

Back when I worked at Appligent Document Solutions, I wrote an article in an attempt to describe this issue in detail.

http://www.appligent.com/talkingpdf-eachpdfpageisapainting

Yes... there's lots of software today that knows nothing of PDF tags and instead delivers text to the end-user in content reading order. Such software cannot conform to PDF/UA.

Could you please clarify your concerns regarding PDF reading order in light of the above facts?

> and
> the presentation of proper pagination is not understood.

PDF/UA requires that conforming software be able to read the PageLabels tree in order to establish the current logical page and thus to facilitate navigation based on that logical pagination. What is "not understood"?

> I think I have been very clear, what is it that you do not understand about
> these accessibility requirements?

See above.

Duff.



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