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Re: PDF Accessibility

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From: Andrew Kirkpatrick
Date: Jan 19, 2010 8:51PM

Dona wrote:
I didn't realize that Acrobat and reader added tags automatically but
weren't permanent etc. There is a lot out there about Acrobat that is not
well known. Can you talk more about that, Andrew?

AWK:
When a user running an assistive technology tool opens a PDF files that lacks tags, Reader will tag it automatically (there are user preferences to allow/disallow/prompt for this). These tags are temporary in that when the file is closed they go away. The autotagging process is the same that occurs when you open a PDF file without tags in Acrobat and select the "add tags" feature, except that the add tags feature is designed to add them permanently since the Acrobat author is able to edit the file.

The heuristic for adding the tags in both cases is not able to add equivalents for images or determine a heading order with complete certainty. It does a good job with the reading order semantics in most cases, but if you have a PDF file with a complex table or columns of text with text boxes interspersed throughout the text I wouldn't be surprised to see tagging issues.

This all comes back to the source file and the data within it. At this point authors have a variety of options for authoring tagged PDF files that are semantically correct, so repair of tagging for PDF files should be less necessary or unnecessary for newly authored PDF files.

Thanks,
AWK

Andrew Kirkpatrick

Senior Product Manager, Accessibility

Adobe Systems

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