- From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Date: Tue, 9 Mar 2010 08:39:18 +1100
- To: Dick Bulterman <Dick.Bulterman@cwi.nl>
- Cc: Eric Carlson <eric.carlson@apple.com>, Michael Smith <mike@w3.org>, HTML Accessibility Task Force <public-html-a11y@w3.org>
Hi Dick, Thanks for the feedback. On Tue, Mar 9, 2010 at 7:21 AM, Dick Bulterman <Dick.Bulterman@cwi.nl> wrote: > Hi Silvia, > > Thanks for the summary. One important point: > >> If we were to introduce the SMIL approach, we would require the >> introduction of the following elements: >> * par >> * switch >> * textstream >> >> instead of introducting: >> * track >> * trackgroup > > This is not really true. Because of SMIL's modularization, you would only > need to take <switch>; <par> and <textstream> have nothing to do with the > <switch> mechanism itself -- they are also defined in different modules. > <switch> is a-temporal and does not rely on or require other aspects of SMIL > timing. (I put these in the example for clarity.> Well, I was looking at the complete need for external associated captions and without the <par> and <textstream> this requirement would not be met. I did say that we could rename <trackgroup> to <switch> if we so wanted, but it would not be compatible with the SMIL <switch> element. > From what you describe, <switch> seems to provide all of the functionality > of <track>/<trackgroup>. It has the advantage that it is more general than > simple media control: it can be used to structure all sorts of underlying > content, such as: No, switch doesn't provide for anything that <track> does, since it does not associate external caption or subtitle or audio description or sign language tracks. Switch is only somewhat equivalent to <trackgroup>. > Whichever way the group goes, I'd recommend also allowing predicate-style > activation on statements NOT wrapped in a <switch> or <track>/<trackgroup>: > this is a very convenient way of handling conditional content. I am confused. What statements would you recommend to add a predicate-style activation to? Right now, all we need to activate is tracks and they have the @enable attribute. So, I wonder if we missed something that you noticed. Regards, Silvia.
Received on Monday, 8 March 2010 21:40:10 UTC