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Re: PDF column tag


From: Duff Johnson
Date: Jul 25, 2022 7:20AM

Bevi makes excellent points, but I want to add a clarification…

It's better to think about “reading order” in a PDF in the following two ways:

- The so-called “Order panel” reveals the physical ordering of content on the page, but cannot reflect the logical ordering, so no headings, lists, tables, alt. text, etc, etc.

- The tag tree, by contrast, describes the logical ordering; consequently, only AT which processes the tag tree may be considered as supporting accessible PDF.

A rough analogy would be a text viewer, which is certainly capable of “reading” HTML, but it isn't a web browser, much less an accessible web browser.