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RE: Longdesc change proposal update

From: John Foliot <jfoliot@stanford.edu>
Date: Sun, 8 May 2011 08:51:58 -0700 (PDT)
To: "'Silvia Pfeiffer'" <silviapfeiffer1@gmail.com>, "'Leif Halvard Silli'" <xn--mlform-iua@xn--mlform-iua.no>
Cc: "'Laura Carlson'" <laura.lee.carlson@gmail.com>, "'HTML Accessibility Task Force'" <public-html-a11y@w3.org>
Message-ID: <049401cc0d97$dbe2abf0$93a803d0$@edu>
Silvia Pfeiffer wrote:
> 
> >
> > Btw, I have suggested (spec text which says) that when a longdesc
> > points to another page, then it should point to the exact fragment
> > where the description begins ... And that there should also be an
> > onvous end of the description. I still think that is a good idea May
> > be, Silvia, if you try to add spec text, should should try to keep
> that
> > perspective?
> 
> I was indeed wondering about that. If longdesc should only be used for
> a11y purposes, then indeed it should point to the fragment offset of
> the long description on the longdesc page. However, I wonder if it is
> sufficient to provide people the opportunity to read that information
> on a separate page that contains other interesting information, too.
> They are already prepared to spend more time on reading about the
> image, so they will probably find the paragraph(s) that provide the
> long description quickly. That would allow the longdesc link to be
> both useful to blind and sighted users.


With no disrespect to Leif, I am not convinced that this is something that
should be *specified* - it might be useful author information in some
instances, but it is overly prescriptive.  There are indeed instances when
a single page of text describing an image is both appropriate and logical,
and adding an id fragment achieves nothing but added complexity.

For example, Dirk Ginader's jQuery plugin
(https://github.com/ginader/Accessible-Longdesc) would become
significantly more complicated it if had to parse page fragments, or
needed to omit extraneous data (replication of the image) - see the
example:
http://blog.ginader.de/dev/jquery/longdesc/examples/webaim/index.php 

As well, looking at plugin solutions such as the WordPress longdesc
module, the author is prompted to provide both an alternative text, as
well as a "description" at image insertion time, and upon submit the
module stores that descriptions as a unique db entry and dynamic url:

<sample>
   <img
src="http://john.foliot.ca/wp-content/uploads/2011/05/dreamweaver.gif"
alt="[Screen Capture: Dreamweaver&#039;s image tag Accessibility
Attributes dialog box]" title="Dreamweaver Dialog Box"
longdesc="http://john.foliot.ca?longdesc=375&#038;referrer=371"
width="510" height="133" class="alignright size-full wp-image-375" /><a
id="longdesc-return-375"></a>
</sample>

So while I am not saying this is right or wrong, I am saying that we need
to be careful what we include as specification text, and what we include
as author guidance, and including id fragments and/or replications of the
image would be, at best, MAY suggestions.

JF
Received on Sunday, 8 May 2011 15:52:27 GMT

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