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Re: Z-Order and Tag Order Need to Match?

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From: L Snider
Date: May 28, 2020 8:33AM

Hi Duff,

Yes, it is complex. However, what I would say is that in Word, we don't
need to deal with layers...So what I am saying is why is PDF different? Now
is Word perfect? Nope...but why are we having to spend endless hours trying
to fix PDFs? This is my question, and I am sorry if I went off the original
answer into the weeds, but how many years we will have the same discussion
about PDFs? I wish EPUB had awesome readers, it would change the ballgame
slowly and surely (I know, another story for another thread!).

Cheers

Lisa

On Thu, May 28, 2020 at 9:56 AM Duff Johnson < <EMAIL REMOVED> > wrote:

> Hi Lisa,
>
> There are no "multiple layers" in the PDF in this sense of the term. There
> is simply... content and tags.
> Content is text, graphics, form fields, annotations, etc.
> Tags are semantic structures (H2, P, Table, etc). These are applied to
> content and are used to describe "info and relationships' as per WCAG SC
> 1.3.1. Tags are the only means of providing these structures in PDF.
> Otherwise I fully agree with you, and am very encouraged to hear that you
> are working to convince other software developers to improve their support
> for Tagged PDF.
>
> Duff.
>
> > On May 28, 2020, at 07:53, L Snider < <EMAIL REMOVED> > wrote:
> >
> > Hi Duff,
> >
> > Unfortunately I know all about these layers, but there is still no
> reason.
> > There is no reason to have multiple layers, what you see should be what
> you
> > get...whether you print, tag or whatever...This is partially why, in my
> > personal opinion, PDFs are still inaccessible. 90% of the ones I have
> seen
> > since 2000 are a problem in some way, and most in major ways. Plus tags
> are
> > just one aspect of PDFs, people will all sorts of disabilities use PDFs
> as
> > you know well.
> >
> > I gave up on Adobe, they moved forward for a long, long time and the last
> > 10 years they moved backward. Not in InDesign, InDesign is amazing and
> > kudos to whoever worked on the accessibility aspect of it, now if they
> > could move back those people to PDF we might get back to where PDF
> > was...Microsoft has been kicking butt in terms of accessibility the last
> 5
> > years, so maybe one day Adobe will follow suit.
> >
> > I am now trying to find other PDF creation programs and convince them to
> do
> > better, may have a shot!
> >
> > Cheers
> >
> > Lisa
> >
> > On Wed, May 27, 2020 at 7:48 PM Duff Johnson < <EMAIL REMOVED> >
> wrote:
> >
> >> Hi Lisa,
> >>
> >> Content order and logical reading order are "separate" in PDF because
> the
> >> technology is obliged to represent content for different purposes.
> >> Rendering (e.g., printing) is a different purpose than accessibility,
> for
> >> example, and often requires ordering of content for processing purposes
> >> that differs from logical reading order. PDF was originally designed for
> >> maximum fidelity in print. Accessibility considerations were only
> addressed
> >> in 2000 with the addition of the Tagged PDF feature to the format.
> >>
> >> In 2020 the difficulty is not in the format but in the software.
> >> Unfortunately it remains the case that...
> >> PDF viewer developers don't do a great job of supporting tagged PDF in
> >> many cases. This is simply a business decision.
> >> Users continue to use software that doesn't understand tagged PDF
> instead
> >> of seeking out and demanding better.
> >> Authors continue to author content without consideration for semantics
> >> (e.g., use tab stops instead of table structures, etc.)
> >> I'll beat my usual drum once again: if you want better PDF support,
> >> complain to those who make your software. Demand better support for
> Tagged
> >> PDF. In 2020 there's simply no excuse.
> >>
> >> Duff.
> >>
> >>> On May 27, 2020, at 18:30, Paul Rayius < <EMAIL REMOVED> > wrote:
> >>>
> >>> As per ISO 32000, one of the intents of PDF is that the "accessible
> >> layer" and the visual layer are independent of each other.
> >>>
> >>> Paul Rayius
> >>> Director of Training
> >>> CommonLook
> >>>
> >>>