Epub's DescribedAt [Was: Drop longdesc, get aria-describedat?]

Silvia Pfeiffer writes:
> The ePub spec is indeed quite a good start. I'd like to see
> requirements on what the browser is required to do with the attribute,
> e.g. the list stated in https://bugs.webkit.org/show_bug.cgi?id=10448.
> 

A good start, perhaps. But also a troubling development from the ARIA
timeline perspective.

Notice that the Epub DescribedAt supports multiple URIs. In our brief
discussion of the underlying use cases, as we understand them currently,
we found we are unconvinced that this simply providing multiple URIs,
space delimited, is either sufficient or the best way to address the
requirement.

On what basis does the user agent choose among the URIs:

*	When the choice is I18N based?
*	When the choise is grade level based?
*	When the choice is some other heuristic?


Let me note that PF and DAISY/IDPF have agreed to discuss architecting
the Epub requirements even before this topic came up in email here.
Regretably, because of various travel schedules, we are unable to hold
that call until early April.

Let me note further that this "multiple target list" requirement could
conceivably postpone ARIA-DescribedAt to ARIA 2.0 by reason of this
added complexity. We've just begun considering the implications
here--and they're significantly more involved than a basic HTML longdesc
replacement feature applicable to various elements.

Janina

-- 

Janina Sajka,	Phone:	+1.443.300.2200
		sip:janina@asterisk.rednote.net

Chair, Open Accessibility	janina@a11y.org	
Linux Foundation		http://a11y.org

Chair, Protocols & Formats
Web Accessibility Initiative	http://www.w3.org/wai/pf
World Wide Web Consortium (W3C)

Received on Tuesday, 13 March 2012 16:18:43 UTC