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Re: reading order

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From: Duff Johnson
Date: Aug 24, 2023 11:09AM

As Karen indicates there are many many cases of documents that cannot be successfully represented to AT users without supporting tagged PDF.

Even if some software can successfully read pages of plain text without headings or columns - which might be ok, sometimes, for student's essays or novels - if it doesn’t understand tags it will fail when asked to read, for example, an invoice, bank statement or newsletter.

Understanding these limitations is *critical information* for end users who are investing precious time and energy in learning how to navigate and read using AT.

Bevi’s advice is good in terms of remediation. I’m not really a fan of technical terminology that’s not rooted in the specification itself… leaving that aside, I do feel compelled to say this much:

First: all PDF software reads PDF’s content streams, otherwise it can’t even produce a page image.

Second, software that ignores PDF's tag tree cannot be reasonably called “assistive technology” for PDF.

Here’s just a few of the things that such software cannot do for end users:

Provide navigation based on headings
Distinguish page numbers from the document content
Represent table or list structures
Represent alternative text
Reliably represent slightly more complex content (such as when two articles appear on a single page)
Represent content that flows across pages (lists and tables do this all the time)
Represent documents that include multiple languages

Indeed, some software that doesn’t support tagged PDF can simulate these things by (for example) guessing at headings or lists… but these are GUESSES, not deterministic representations of the document’s content.

If some tool that doesn’t support tagged PDF is otherwise pretty good at guessing, for example, headings on a given document, the user should know the truth: they got lucky. If it works on one document it will likely fail on a different document. Certainly, users with different software will get different results.

Software that does not comprehend PDF’s tags tree should not be represented as “assistive technology”. If it is, users will spend time and energy learning something that will either mislead them or fall over as soon as slightly more complex content is encountered.

The only solution is to address deficiencies with AT software directly with the vendors themselves. Make some noise!

> Academic institutions discover this every day. Their students come into class with everything under the sun, and their files have to work with those non-compliant technologies. Government, too. They can't tell students and taxpayers which software tools to use!

What they can do is clearly and consistently advise their users of the limitations in their software, and not pretend that software that cannot use tagged PDF is reasonably labelled as “assistive technology”.

In many cases governments can require their organizations to be aware of and use proper technology. Likewise, academic institutions - if they purport to serve students with disabilities - must educate their students on what works and what doesn’t, and provide respective options.

Duff.

> On Aug 24, 2023, at 08:00, Karen McCall < <EMAIL REMOVED> > wrote:
>
> A caveat to determining the reading order is that if you have a PDF where half of the document is English/for example and the other half is French/for example, and the English is in a column on the right and the French is in a column on the left, organize all of the English content together in the Tags Tree and all of the French content together in the Tags Tree so that someone not familiar with either language will read all of the content in the language they know without having to switch midway through a thought or paragraph and ending up lost in the document.
>
> This goes for tri-fold brochures as well. The reading order for the first "page" should be the title panel of the brochure, followed by the inside panels and then back to the first "page" to read the last two panels in order. This is done in the Tags Tree.
>
> Newsletters with articles broken over pages is another example of ensuring that all of an article is read together which is done in the Tags Tree.
>
> I don't know of a way to do this in the Order Panel/Reading Order Panel or Content Panel. Those tools tend to focus on a single page rather that the logical reading order of content in the document as a whole.
>
> Another remediation in the Tags Tree is to ensure that paragraphs, lists and tables that span multiple pages are "joined" in the Tags Tree.
>
> Cheers, Karen
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of <EMAIL REMOVED>
> Sent: Thursday, August 24, 2023 12:35 AM
> To: 'WebAIM Discussion List' < <EMAIL REMOVED> >
> Subject: Re: [WebAIM] reading order
>
> When remediating PDFs, we stress this process in our classes:
>
> (Caution: this is a longish, detailed answer)
>
> 1. Examine the PDF. Use your eyes first and see how accurate the tag tree is — check both the tags themselves and the tag reading order.
>
> 2. If there are any changes that need to be made, make them in the Order panel (with what you're calling TURO, touch up reading order, but Adobe removed that great name a few versions back). This order is more accurately called the Architectural Reading Order because it's based on the actual encoding of the content in the PDF file — a k a, the architecture of the file's code.
>
> The tag tree, on the other hand, is more like an overlay above the actual content stream.
>
> You can use the Content panel, too, but it's more disorganized and the newest version of the Architectural Order panel has easier options for tagging large portions of text like paragraphs, notes, etc. With today's versions of Acrobat, we go into the Contents panel less frequently than before and usually only to artifact something.
>
> 3. Any changes made in the Architectural Order — both with tags and the reading order — will also be made in the Tags tree. But note, if you first make those same changes in the Tag tree, they will NOT be made in the Architectural Order panel. The process goes from Architectural Order to the Tags tree, not vice versa.
>
> 4. Run the internal Acrobat checker and any 3rd party checkers of your choice. And also run Acrobat's built-in Preflight for PDF/UA, which can check and fix many technical problems (not with tags or reading order, however).
>
> 5. Have a human who has a disability review the file, too.
>
> RE: the importance of the Architectural order...
>
> It's the core foundation of a PDF file and contains the "content stream" which is the actual live text and graphics encoded into the file. It's used by a lot of technologies, not just those specifically for accessibility. Most of our cross-media technologies use this order, not the tag tree order. So if your content will migrate to two or more different technologies, like XML or HTML, the Architectural order is critical.
>
> So there are a lot of assistive technologies that still use this core part of the program and completely ignore the tag tree (note that I'm told by programmers that it's much more difficult to program for tags than it is for the content stream). Many tools look at the Architectural reading order, especially those tools that are free.
>
> I have many family members with major sight and mobility disabilities (inherited disabilities) and universally, their social workers teach them to use the free tools, especially in the early stages of their disability. They may eventually migrate to a more formal assistive technology later, but in the beginning they're using easy and cheap technologies that often don't recognize or voice the tags.
>
> Academic institutions discover this every day. Their students come into class with everything under the sun, and their files have to work with those non-compliant technologies. Government, too. They can't tell students and taxpayers which software tools to use!
>
> If you've read this far, you can check our blog about a PDF's 4 reading orders at https://www.pubcom.com/blog/2020_08-18_ReadingOrder/reading-orders.shtml
>
> Hope this helps.
>
> — — —
> Bevi Chagnon | Designer, Accessibility Technician | <EMAIL REMOVED> — — —
> PubCom: Technologists for Accessible Design + Publishing consulting • training • development • design • sec. 508 services Upcoming classes at http://www.pubcom.com/classes
> — — —
>
>
> -----Original Message-----
> From: WebAIM-Forum < <EMAIL REMOVED> > On Behalf Of Laura Roberts
> Sent: Wednesday, August 23, 2023 1:26 PM
> To: WebAIM Discussion List < <EMAIL REMOVED> >
> Subject: Re: [WebAIM] reading order
>
> Glen, it gives some interesting info about how reading order in Word and InDesign is determined, but they don't get into the weeds of the Tag Panel, Content Panel and TURO. And they mainly talk about changing the source document.
>
> The reality of my business is that my clients have their own clients who are mostly large bureaucracies and in order to change a source document, they have to have a zillion meetings with their client and jump through so many hoops. So it's often the case that my clients do not have the ability to change the originals around to make them more accessible. And I'm on the very end of this process, so I have zero ability to change the source in any sort of fundamental way. The upside of that is that I've become skilled at fixing very complex pdf problems over the past decade.
>
> Btw, my favorite go-to person over the years has been Bevi Chagnon! I don't know her, but she has helped me when no one else could quite a few times.
>
> On Wed, Aug 23, 2023 at 1:06 PM glen walker < <EMAIL REMOVED> > wrote:
>
>> One of my "go to" guys for PDF accessibility is Dax Castro. He posted
>> a podcast last week that talks about this.
>>
>> https://www.y/
>> outube.com%2Fwatch%3Fv%3D_EoWeqAPOyE&data%7C01%7C%7C82e945af411047f
>> 8e7b708dba45b9e61%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C6382844
>> 85651779123%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMz
>> IiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=bTyE7OtGSE6K4od
>> giQYxqu99%2Fe7OKe6ZlkASDDLWoSM%3D&reserved=0
>>
>> I haven't fully watched it yet so it might say the same thing that
>> Steve said.
>> >> >> http://list.w/
>> ebaim.org%2F&data%7C01%7C%7C82e945af411047f8e7b708dba45b9e61%7C84df
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>> I6Mn0%3D%7C3000%7C%7C%7C&sdata=WGN1D2JqSBeLQloUgKZXU6TXYPLAWBSzxvtvTYC
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>> 123%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTi
>> I6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=%2BvLZxV1jF9aLNRhlRAMY5
>> 0zSN0SzmMjLTxqa7EynJDY%3D&reserved=0
>> >>
>
>
> --
> Best regards,
> Laura Roberts
> 413-588-8422
> > > >
> > > > > > > >