RE: [Fwd: SMIL 2.0 comment: 14.3.2 Conformance of SMIL 2.0 Basic Documents]

Hi Aaron, 

Thanks for the answers. I have a few more questions. See below.

Peter writes:
> > 
> > * As a content author, I would like to write one SMIL 
> > presentation for advanced players and another for basic 
> > players (A common use case, I think). How can I make sure 
> > that my document only contains the basic modules?

Aaron writes:
> You only have to write one smil file. You can use the test attribute
> 'systemRequired' to ensure that the SMIL Basic player doesn't 
> have to look
> at anything that it doesn't know about. You just wrap non 
> SMIL Basic block
> with systemRequired=<non-smil-basic-module-ns-prefix> and you're set.
>

No. I WANT to write one presentation for the Basic player and another for the advanced player. The two presentations may be presented on very different types of devices. As a content author, I want to make sure the SMIL basic document only contains Basic modules. If there had been a DTD/Schema for Basic, it would have been very easy to check. 

(Web developers today typically create one version of their site for mobile phones and another for regular desktops. )

[snip]

Peter writes:
> > * How can, for example, a mobile phone indicate to the server 
> > that it supports only SMIL Basic modules, 

Aaron writes:
>
> This is a CC/PP thing, and orthogonal to SMIL
>

Ok. So you rely on CC/PP for this, and the HTTP Accept header cannot be used. With CC/PP the content developer has plenty of information about the client's capabilities, but I think content negotiation should work also with HTTP. 

Working on the XHTML MIME media type, we have been considering a parameter that is used to identify the profile. The name of the parameter is still under discussion ("profile" or "schema-location") but in order to identify XHTML Basic, the media type will look something like this:

application/html+xml, schema-location="http://www.w3.org/TR/xhtml-basic"

Would it not be possible to do something similar for SMIL Basic?

[snip]
 
Peter writes:
> > * If an external organisation, for example WAP Forum, use 
> > SMIL 2.0 and use their own namespace, as you suggest below 
> > that they can, then what happens when the document is sent to 
> > a SMIL player that does not recognize the 
> > organisation-specific namespace? 

Aaron writes:
> It would not play the document, since elements in distinct 
> namespaces are by
> default distinct. However, it would not be very much coding 
> work for such a
> player to recognize such document types, since it would be 
> just accepting
> essentially the same elements from an alternative namespace. 

So we may end up with the name "smil" in many different namespaces: a WAP Forum "smil", a 3GPP "smil", and so on. That would be very bad! An element name should be in no more than one namespace. Are you expecting that if an organisation or company define their own SMIL profile with a new namespace, that existing SMIL players will support the new names of the elements?


Peter

Received on Thursday, 15 March 2001 08:38:46 UTC