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Thread: Re: FW: PDF is only partially accessible

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From: Simius Puer
Date: Fri, Dec 04 2009 3:42AM
Subject: Re: FW: PDF is only partially accessible
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Hi Wayne

This is a brilliantly in-depth and thorough look at PDFs from the
perspective of a specific disability group.

I agree that Adobe have done a huge amount over the past 10 years or so to
bring the PDF format up to scratch in terms of accessibility and they have
by-and-large done a great job.

There are a few reservations that I hold regarding your notion that "I think
PDF needs to go one more step to be classified as accessible without
qualification":

1. No format can be considered "accessible without qualification" - that
is a dangerous statement that could lead non-technical people to think that
anyone can produce an accessible PDF without training. Any format is only
as accessible as the people publishing make it - I'd hate for your words to
be taken out of context or misinterpreted as I see that happen all too often
on the Web.
2. As a format for Web content the user experience is still jarred by the
use of PDFs. The user is taken away from their browser, to the PDF reader,
and then has to return to to the browser. Most of us take this for granted,
but then again, a great many of us take sight and other abilities for
granted too. Not everyone is as web savvy as developers like to think and I
know many people who get confused by PDF content (especially if the link to
it doesn't warn them first - the web editors fault, not Adobe's of course),
new windows and the like. These people could not really be labeled
"disabled" as such but I think they would be a good representation of the
"cognitive" group of disabled user.
3. There are other disabled user groups that need to be considered - not
just users with sight problems.

I'm sure Adobe will be most interested in your input and I'm sure you will
find them very accommodating. I have met with them in the past and they are
very keen to listen and improve their products, plus I see some of their
representatives getting involved in this forum (hi there). Given the
progress they have made with PDF I don't think a few more steps will pose a
problem.

Even with all the accessibility in place I am still utterly unconvinced as
to the use of the format as the primary format for delivery of Web content
for so many other reasons. PDFs have their roles, but that isn't one of
them.

Possibly a tiny bit off-topic (but not by much) - ironically, viewing this
thread in Gmail I am presented with multiple ads for free "PDF to HTML" and
other such converters. I shudder at the memory of testing many of those
products. Sadly whilst free software exists businesses will often be
attracted to them (especially given the cost of Acrobat) - it would be nice
to see Adobe tackle this but I can't see a business model for them to
release Acrobat/Acrobat Pro for free.

Best of luck with your effort in getting the Daisy translator!

From: deblist@suberic.net
Date: Fri, Dec 04 2009 7:24AM
Subject: Re: FW: PDF is only partially accessible
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On Fri, 4 Dec 2009, Simius Puer wrote:
> Not everyone is as web savvy as developers like to think and I
> know many people who get confused by PDF content (especially if the link to
> it doesn't warn them first - the web editors fault, not Adobe's of course),
> new windows and the like.

it's not just a matter of Web savviness. For many completely
web-savvy users with disabilities, switching to PDF or
flash-based content can simply be a matter of spoons. Opening up
a PDF, and then formatting it in such a way that I can see all
the text on a page in a readable size font and scan the content
(which is ultimately what I care about, not the layout) without
using a mouse is a royal pain. I know perfectly well how to do
it, but when computer users with disabilities are confronted with
just one more roadblock in the Big Dig is our computer using
experience, many of us will choose to take a side route.

As a general rule, PDF content on the web is something I avoid
unless I have no choice. Yes, technically I can navigate a PDF
accessibly, but it is such a chore to do so that why would I ever
spend spoons on a PDF when there is so much else to do?

-deborah

From: Simius Puer
Date: Fri, Dec 04 2009 8:33AM
Subject: Re: FW: PDF is only partially accessible
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Indeed, and please don't mistake my standpoint - I did say PDFs have a
place, but that's *not *to provide the primary format for Web content. I
was just pointing out that there are multiple different reasons why the
choice of format for Web publishing is very important.

I have no real disabilities but even I avoid using PDFs online where I can.

From: Geof Collis
Date: Fri, Dec 04 2009 8:45AM
Subject: Re: FW: PDF is only partially accessible
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And that is it in a nutshell, give me choice!!

cheers

Geof
At 10:32 AM 12/4/2009, you wrote:
>Indeed, and please don't mistake my standpoint - I did say PDFs have a
>place, but that's *not *to provide the primary format for Web content. I
>was just pointing out that there are multiple different reasons why the
>choice of format for Web publishing is very important.
>
>I have no real disabilities but even I avoid using PDFs online where I can.
>
>
>

From: Andrew Kirkpatrick
Date: Fri, Dec 04 2009 8:48AM
Subject: Re: PDF is only partially accessible
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Wayne,
Thanks for sharing your thoughts. I don't agree with everything you say, but there is no question that there is more work to do to improve upon the level of support that exists in PDF today. I'll provide comments inline - I'm going to break down many responses into comments on two aspects of accessibility, what is required by accessibility standards and what is best for users, as that seems to be what you are doing also.

I'll also preface my comments by pointing out that the issues that you point to are not necessarily an issue with PDF. There are a few players - the PDF (ISO32000) format, the PDF authoring tool used (and how the author uses it), and the PDF viewer being used. I'll also frame my comments around these.

I want to also make sure that you are aware of the work going on in the PDF/UA (Universal Accessibility) AIIM/ISO work group, if not you should take a look.

What we need is enhanced text. That means size control that is
not uniform for all tagged text types, e.g. paragraphs should be
enlarged more than headings.

This is not an issue with the PDF format, this is how the data is rendered by the PDF viewer. You're right, this we don't currently do in Adobe Reader, although it is clear what you are looking for. Can you indicate what accessibility standard requires this?

We need clean and simple font families
like Arial, Verdana or Tahoma.

This is not an issue with the PDF format, this is also how the data is rendered by the PDF viewer.
While you can't change the font in Adobe Reader, the document can be authored in these fonts, at the author's discretion.
Can you indicate what accessibility standard requires that users must be able to change the font?

We also need spacing control over letters, words and lines.

What spacing control for letters and words do you need? I know that WCAG 2.0 SC 1.4.8 (AAA) covers line and paragraph spacing - does that adequately describe what you need?
Is there any accessibility standard that covers letter and word spacing?
The text is available in the PDF file, so other readers might do this, or an add-on could re-render the text of the PDF in this or any other way you want.

This is a direct deficit according to WCAG 2.0 Criteria 1.3.1.

1.3.1 refers primarily to programmatic access, with a text fallback. From http://www.w3.org/TR/UNDERSTANDING-WCAG20/content-structure-separation-programmatic.html: "Some technologies do not provide a means to programmatically determine some types of information and relationships. In that case then there should be a text description of the information and relationships." Since reader satisfies 1.3.1 programmatically the fallback is unnecessary.

I don't think that 1.3.1 applies to the items you list above, but that is not to suggest that the items you mention are not important to some users of course.

PDF fails to support
Guideline 1.3, Criteria 1.3.1, Sufficient Technique G140.
Adaptable:

Guideline 1.3 Create content that can be presented in different ways
(for example simpler layout ) without losing information or structure.
Understanding Guideline 1.3 . PDF fails to support this Guideline
because it fails to support 1.3.1 completely at the text level.
Info and Relationships:

Criterion 1.3.1 Information, structure, and relationships conveyed
through presentation can be programmatically determined or are available
in text. . PDF Fails this Criterion because text objects in PDF cannot
be restyled visually an effective format for people with moderate low
vision.

I don't believe that this success criteria requires the restyling that you indicated above. 1.4.8 does require some of this, however.

Sufficient Technique G140: Separating information and structure from
presentation to enable different presentations . -- Not supported
completely by PDF.

I think that you are misunderstanding what a sufficient technique does - no technology has to comply with any given sufficient technique - it is just one way that is deemed to be sufficient to meet the success criteria. However, I do believe that PDF does separate information from structure.

The text contents within paragraphs, lists and table cells appear to be
immutable regarding the style properties: font family, spacing of
letters, words and lines. That means the user cannot adjust necessary
presentation style properties to support reading. This interferes with
the person's ability to separate figure from ground.

Adobe Reader doesn't allow the modification of the rendered text in the ways you mention, but the text and structure is present in the PDF format and in the accessibility interface provided by Reader. These modifications are possible, it is just that Reader doesn't currently do them.

There are accommodations and alternative media than can give a
significantly inferior experience for this group. This is a well known
fact because HTML and most Word Processing formats (doc, docx, rtf, odt)
can product the exact formats that respect these needs of moderate low
vision completely. So, objectively, PDF is not as accessible as word
processing formats or HTML.

To be clear, you mean not as accessible to the low vision population.

From my point of view, life would be much
better off if every posting in PDF was also posted in one of the
completely accessible formats.

I have to take issue with your characterization of all of these formats as completely accessible.

How well do formats like these support tables/complex table semantics for blind users. PDF supports this.
How well do formats like these support structural headings? I don't believe that RTF supports this, but PDF does.
How well do formats like these support image equivalents? It is in the RTF spec, but I don't believe that tools that support RTF support this, but PDF does.

These other formats have their strengths, but I don't believe that the doc, docx, or rtf specs have as complete a level of accessibility in the spec as PDF does (I can't comment on odt offhand). Some of these differences are apparent in PDF documents when using Reader (e.g. headings & image equivalents in Reader but not RTF, complex table support in Reader but not doc/docx), but there are rendering differences like the ones you highlight where there are differences that you feel make the non-PDF formats more accessible. These are the things that we should talk about as enhancement requests for Adobe Reader.

Accessibility for reading documents
means that the user with a disability can use a program to produce a
format for reading that is just as usable as the format developed for
the primary audience. Anything less is not completely accessible. That
is why PDF is only partially accessible. People with moderate low
vision cannot get an equally effective experience when they are forced
to read PDF as their only choice. Unfortunately, large institutions
have jumped on the notion that PDF can be made completely accessible,
and the presence of stand-alone PDF postings is accelerating. This is a
sad occurrence for those of us whose quality is directly reduced by this
trend.

Wayne, I'm a little lost with this comment - are you talking about users authoring PDF or reading PDF? You start with one but continue with the other. Can you clarify?

Until this issue is resolved to the satisfaction of people with low
vision, Adobe should not encourage the belief that their product can be
made totally accessible.

As mentioned in a follow-up comment, I wouldn't characterize anything as totally accessible. PDFs can be highly accessible and can meet WCAG 2.0 AA. There are some issues, including some of the ones you cite above that make WCAG 2.0 AAA difficult to fully meet.

I'm glad that you took the time to post your thoughts, and we are happy to discuss enhancement requests for Reader. We do want to both address what users need as well as what is directed by accessibility standards, so I hope that you can address some of my questions above.

Thanks,
AWK

Andrew Kirkpatrick

Senior Product Manager, Accessibility

Adobe Systems

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