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Re: Survey ready on Media Text Associations proposal

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Tue, 9 Mar 2010 08:39:18 +1100
Message-ID: <2c0e02831003081339o7140e1fcy140414cd4dbbffe5@mail.gmail.com>
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 GMT

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