To add to Dick's SMIL example, I have taken the examples from the Text
Associations wiki [1] and coded the SMIL equivalents [2].
mark
[1] http://www.w3.org/WAI/PF/HTML/wiki/Media_TextAssociations
[2] http://www.talkinginterfaces.org/lab/video/html5smil.html
On Fri, Mar 5, 2010 at 7:10 AM, Dick Bulterman <Dick.Bulterman@cwi.nl>wrote:
> On the track proposal, just to make sure I'm not missing something:
> Is there an implied preference order in the statements:
>
> <trackgroup media="accessibility(captions:yes") >
>>
>>> <track src="en.srt" lang="en" enabled >
>>> <track src="fr.srt" lang="fr" >
>>> <track src="de.srt" lang="de" >
>>> </trackgroup>
>>>
>>
> (In other words, the implied preference order is English, French, German.)
>
> Compare this to the SMIL way of doing the same thing:
> <par>
> <video src="..." />
> <switch systemCaptions="on" allowReorder="yes">
> <textstream src="en.xxx" systemLanguage="en" />
> <textstream src="fr.xxx" systemLanguage="de" />
> <textstream src="de.xxx" systemLanguage="de" />
> </switch>
> </par>
> The default behavior is that the first candidate matching a set language
> preference is used. The 'allowReorder' attribute explicitly allows a user
> agent the reorder the order of options if the user (via the UA) has
> determined that he/she prefers German over French.
>
> Note also that in this example, the entire <switch> is only evaluated if
> the user (agent) has determined that captions are required. Note finally
> that if the user has the language preference Dutch, no captions will play
> (since he presumably can't understand them anyway). Having a final statement
> in a <switch> without a predicate determines a result that will allows play
> if no earlier option (reodered or not) do not provide a preference match.
>
> Are the semantics of <trackgroup> similar? (If so, why invent something
> new; if not, are at least the SMIL semantics supported?)
>
> -d.
>
>
>