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Re: PDF is only partially accessible

for

From: Andrew Kirkpatrick
Date: Dec 4, 2009 8:48AM

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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