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Re: PDFs that read one word per line


From: Monir ElRayes
Date: Jan 28, 2010 4:15AM

On 28 Jan 2010, at 5:30 AM, Mark Magennis wrote:

> Correctly structured and fully tagged PDFs are typically NOT as accessible
as an equivalent HTML
> document.

This is because in most cases these PDFs are not truly properly structured.
The problem is simply this: Making PDF accessible is much harder to do
manually (i.e. using just Acrobat) than HTML. Hence the large number of
non-accessible PDFs out there. This is due to the fact that PDF is
inherently a much more complex format than HTML. People confuse this with
the PDF format not being capable of providing the same level of support for
accessibility as HTML. Using the right tools, PDF files, including those
containing complex data tables, can be read correctly using Screen Readers
and the Read Out Loud feature of Acrobat.

My company develops software tools for HTML and PDF accessibility and I can
tell you that our experience, based on remediating tens of thousands of
PDFs, is that PDF can be made as accessible to end users as HTML when the
right tools are used. Granted that most PDFs out there are not accessible
and there is lots of confusion and frustration due to the difficulty of the
task (when done manually).


-----Original Message-----
[mailto: <EMAIL REMOVED> ] On Behalf Of Mark Magennis
Sent: January-28-10 5:30 AM
To: WebAIM Discussion List
Subject: Re: [WebAIM] PDFs that read one word per line

On 26 Jan 2010, at 15:54, Monir ElRayes wrote:

> Once remediated, a PDF document is typically as accessible as an
> equivalent HTML document.

Only if you are in a closed space (e.g. a company Intranet) where you
can guarantee what assistive technologies users (your employees) have
available to them. Or if your definition of "accessible" doesn't
relate to real users and their real situations. For PDFs on public
websites, your statement is false. Correctly structured and fully
tagged PDFs are typically NOT as accessible as an equivalent HTML

For real world accessibility, you have to embrace the notion of
"accessibility support", which is the extent to which users' assistive
technologies can read and interact with a given type of content (e.g.
an image or an interactive form) in a given format (e.g. HTML or PDF).
PDF does not have the same level of accessibility support as HTML
does. The use of PDF for types of content other than plain text is not
as well supported by assistive technologies as the use of HTML for the
same types of content. For example, you can create an interactive
application form in HTML which can be read and filled in using just
about any assistive technology. But the same form in a PDF may not
work with older assistive technologies which many people with
disabilities still have. In Ireland, for example, we estimate that
about 65% of JAWS screen reader users have versions 5 to 7. If they
had the latest version, JAWS 11, then they would be able to fill in
the PDF version of the form as easily as the HTML version. But they
don't. So even a correctly structured and fully tagged PDF on a public
website will not have the same level of real world accessibility as a
correctly marked up HTML version, if it uses types of content that are
less accessibility supported.


National Council for the Blind of Ireland (NCBI) is a company
limited by guarantee (registered in Ireland No. 26293) .
Our registered office is at Whitworth Road, Drumcondra, Dublin 9.
NCBI is also a registered Charity (chy4626).

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