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Re: PDF reading order and tag order

for

From: Chagnon | PubCom
Date: Jun 7, 2017 11:07AM

Quote: "The most important order in an accessible PDF is the tag order viewable in the Tags pane."

I'd say that "most important" is in the mind of the individual!

If you were deaf/blind, you'd be using a braille device like a braille keyboard, which most likely would use the Order reading order, not the Tag reading order.

Many other A.T. for cognitive, neurologic, and mobility disabilities use the Order, too.

Bottom line: both reading orders are important if you want to provide accessibility to all of your users.

--Bevi Chagnon

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Bevi Chagnon | www.PubCom.com
Technologists, Consultants, Trainers, Designers, and Developers
for publishing & communication
| Acrobat PDF | Print | EPUBS | Sec. 508 Accessibility |
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-----Original Message-----
From: WebAIM-Forum [mailto: <EMAIL REMOVED> ] On Behalf Of Philip Kiff
Sent: Wednesday, June 7, 2017 12:57 PM
To: <EMAIL REMOVED>
Subject: Re: [WebAIM] PDF reading order and tag order

On 2017-06-07 12:18, Alan Zaitchik wrote:
> [....]
> But I have 2 questions.
> 1. The Acrobat Reading order tool jumps around with little regard (it
> seems) for my reordering and restructuring the tabs, even though I set
> my 'Preferences' for reading order to 'Infer from document structure'.
> Is this bogus? Need I be concerned? When I use the tool to reorder it
> screws up the tags!
The Acrobat "Touch Up Reading Order" tool is poorly named and the order shown by the numbers in Acrobat can be misleading until you understand that there is more than one "order" in a PDF.

The most important order in an accessible PDF is the tag order viewable in the Tags pane. The Order pane does not show this order, but instead shows the "Content" order which is based on how the content is actually placed in the file.

Screenreaders use the Tag order. Adobe's built-in Read Aloud feature I think uses the Content order.

To change the Tag order you simply move tags up and down the Tags pane.
To make the Content order match the Tags order, you can try moving things around in the Order pane or directly in the Content pane itself.
However, your viewable content and your tags can easily get screwed up if you use the Order pane to move things around, especially if you have any tags nested inside other tags (like Spans or Figures inside P's inside Article's).

The WebAIM site has a pretty good explanation of how to re-order a PDF file here:
http://webaim.org/techniques/acrobat/acrobat#touchup

I like to think of the Content order as something like the "printing"
order, because if you start moving these items around you can end up making some items disappear behind others, as though they have been "printed" over by a non-transparent block of text or figure that appears after them in the content order.

If forced to choose, always prioritize getting the tag order right rather than the Order panel order.

> 2. I did indeed create 4 <article> sections but was unsure whether I
> should group the banner elements in some section or just list them as
> direct children of <document> ahead of the first <article>. My concern
> here is to use only well-supported HTML5 tags that will work with JAWS
> and other screen readers. Is the following structure OK?
> <Document>
> <Figure>
> <H1>
> <P>
> <Article>
> <Article>
>
> <Article>
>
> <Article>
>
Your structure looks okay to me!

Phil.