On Wed, 12 Aug 2009 01:09:16 +0200, Remco <[email protected]> wrote:
As a small part of integrating the ideas of ARIA into existing HTML 5,
I just got an idea for a better solution for replacement content for
video and audio: <source>.
The source element is used to provide media elements with multiple
sources. What if one of those sources could be an element on the page
itself? The text is just another source which could link off-page, or
on-page.
<video>
<source type="video/theora" src="primary-content.ogg">
<source type="text/html" src="#alternate-content">
<source type="text/html" src="alternate-content.html">
</video>
Alternative content in <source> which comes from an element on the
same page is an extension to what you already know, and it doesn't
require you to know about a special accessibility part of HTML.
In addition: currently, <source> is only used for <audio> and <video>,
but why not extend it to any external element?
<iframe src="primary-content.html"><!-- legacy -->
<source type="text/html" src="primary-content.html">
<source type="text/html" src="#alternate-content">
<source type="text/html" src="alternate-content.html">
</iframe>
<object><source ... ><source ... ></object>
<embed><source ... ><source ... ></embed>
<img><source ... ><source ... ></img>
That last one may be problematic, since img-elements have
traditionally never had a closing tag. I don't know how browsers will
react to something like that. Maybe it would be better to have alt=
and longdesc= remain for the img-element, and give longdesc the
aria-describedby functionality (it could link to an element on the
same page) in addition to the original meaning.
Before suggesting any changes to the <source> element, make sure you have
read
http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#concept-media-load-algorithm
Put simply, the handling of <source> is already quite complex, overloading
it with completely different meanings is not a good idea. <video> won't
handle "text/html" as a source, but if you want different media files for
different audiences I suggest experimenting with <source media>.
--
Philip Jägenstedt
Core Developer
Opera Software
