what must be done to expose longdesc? [was Re: fear of "invisible metadata"]


the first thing a screen-reader must do when it discerns the 
presence of a longdesc target is: ALERT THE USER THAT IT IS 

the second thing a screen-reader must do when it discerns the 
presence of a longdesc target is to allow the user to activate 
that target, if that is the user's wish, so as to expose the 
contents of the longdesc document; ever since it began to support 
longdesc JAWS for Windows 1) alerts you to the presence of a long
description, and prompts the user (in basic mode) to hit ENTER, 
and the contents of the longdesc document associated with the 
image is displayed in a pop-up window (not the best solution 
when the default for a lot of programs these days is block all 

the last thing that needs to be done is to provide a mechanism 
to return to the document in which the described image is 

obviously, step 1 is the responsibility of the assisstive 
technology, but the under-the-hood mechanics of exposing 
descriptive content SHOULD be the user agent's responsibility; 
what is needed is a normative list of recommended slash 
expected actions that allow multi-modal interaction with the 
long description.

as i have indicated, treating LONGDESC as HREF isn't the only 
means of exposing the content of the long description page; 
the contents -- or the main portion thereof -- could be rendered 
inline instead of the image or in an IFrame (which has its own 
accessibility issues) or any other number of means of exposure.

the key is that the UA should support LONGDESC natively, and 
allow the user a set of choices about exposing LONGDESC:

* expose in new browser instance
* expose in new browser tab
* expose inline (insert content as object)
* expose inline through the use of IFrame
* expose the contents of the longdesc document in a side-bar,
  aligned with the image it describes

and many many others...  if a user knows what to do when 
encountering a long description, then it matters not what 
assisstive technology she is using, for there is an expected 
action in the case of browser x for exposing LONGDESC

PEDESTRIAN, n. The variable (and audible) part of the roadway for
an automobile.       --  Ambrose Bierce, _The Devil's Dictionary_
Gregory J. Rosmaita: oedipus@hicom.net and webmaster@ubats.org
UBATS: United Blind Advocates for Talking Signs: http://ubats.org

---------- Original Message -----------
From: Maurice Carey <maurice@thymeonline.com>
To: HTML Working Group <public-html@w3.org>
Sent: Thu, 21 Jun 2007 17:45:46 -0400
Subject: Re: fear of "invisible metadata" [was Re: retention of summary   
attribute  for TABLE element]

> On 6/21/07 5:42 PM, "Joshue O Connor" <joshue.oconnor@cfit.ie> wrote:
> > 
> > Maurice Carey wrote:
> >> Does anyone know, when a screen reader encounters a longdesc, does it
> >> navigate to the long description or does it pull it up behind the 
scenes and
> >> read it out loud in context?
> > 
> > No, it doesn't do either.
> > 
> > Josh
> > 
> > 
> > 
> So what does it do? Or what would the user do to make use of its 
> existence?
> -- 
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------- End of Original Message -------

Received on Sunday, 24 June 2007 19:33:12 UTC