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Re: Which A.T. uses the R.O.?

for

From: Chagnon | PubCom
Date: Aug 5, 2014 2:58PM

Thanks Olaf for the excellent detailed explanation. You confirmed what I
thought.

It appears that we still have some assistive technologies that use the RO
(z-order) rather than the tag order, but there's hope it will become
obsolete sometime in the future.

If anyone has a particular AT that uses the RO, other than braille keyboards
and printers and Kurtzweils, please let us know. I'm trying to document
which items use this.

To clarify for others on the list, "raw page description" is basically the
code written into the PDF file and it directly correlates to the sequence of
steps the user made to create the document.

When using MS Word to create a PDF, this sequence usually follows from
top-down and left-to-right, so the reading order (or z order) usually is the
same, top-down, left-to-right (ok, forget the tragic flaw in Word 2010 and
think instead Word 2013 which places anchored objects in the correct order).

The problems arise when PDFs are made from visually rich documents, like
those from Adobe InDesign, M.S. Publisher, and M.S. PowerPoint. In those
programs, the authors place items all over the place and not necessarily in
the top-down left-right order. And their sequence of mouse-clicks used to
create the document are all over the place, too. It's that sequence of
mouse-clicks (or placement of items like text blocks and graphics) that
don't follow a logical reading order at all.

Hence, really crazy reading orders (z-order) in the resulting PDF, even
though the tag reading order is just fine.

—Bevi Chagnon
— — —
www.PubCom.com — Trainers, Consultants, Designers, Developers.
Print, Web, Acrobat, XML, eBooks, and U.S. Federal Section 508
Accessibility.
Taka a Sec. 508 Class in 2014 — www.Pubcom.com/classes

-----Original Message-----
From: <EMAIL REMOVED>
[mailto: <EMAIL REMOVED> ] On Behalf Of Olaf Drümmer
Sent: Tuesday, August 05, 2014 1:16 PM
To: WebAIM Discussion List
Subject: Re: [WebAIM] Which A.T. uses the R.O.?

Hi Bevi,

- tools that do the PDF reading themselves tend to read the raw page
description in a PDF file will end up reading stuff in the z "Order" (as
reflected in the "Order" tool in Acrobat). These tools will present content
in the same order as it would be rendered by the reflow tool (for example
last time I checked a year or two ago, ZoomText did this). Also, on iOS all
tools seem to do either do the PDF reading themselves or rely on the iOS
built in PDF engine, both present content in the raw page description order.
If only Apple started to get its act together and make use of the tagging
structure in PDFs…
- tools that rely on the accessibility interfaces supported by Adobe Reader
/ Adobe Acrobat will follow the order of the tagging structure (definitely
NVDA, but probably also JAWS). Speak aloud in Adobe Reader and Adobe
Acrobat and also "save as accessible text" in Acrobat will present content
in this order.

Note that there are also some tools that ultimately just do OCR all the
time, tools from Kurzweil tend to fall into that category.

Braille keyboards and printers will always have to rely on some piece of
software - it's that software that is doing the PDF reading, and it depends
on that software which order is being followed.

Olaf


On 5 Aug 2014, at 18:46, Chagnon | PubCom < <EMAIL REMOVED> > wrote:

> Doing research and need to clarify which assistive technologies use a
> PDF's reading order (not the tag reading order but the blue Z "Order"
> tool in Acrobat or the Reflow utility).
>
> So far I've identified braille keyboards and braille printers. I
> believe some older versions of screen readers use it, too.
>
>
>
> Are there any other A.T. for blind and visually impaired users that use
it?
>
> And are there any A.T. for users with mobility disabilities that use it?
> -Bevi Chagnon