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

Peter:
Some replies in-line.
-Aaron

> -----Original Message-----
> From: Peter Stark (ECS) [mailto:Peter.Stark@ecs.ericsson.se]
> Sent: Wednesday, March 14, 2001 1:37 AM
> To: 'Kenichi Kubota'; 'Cohen, Aaron M'; Philipp Hoschka; 
> www-smil@w3.org
> Subject: RE: [Fwd: SMIL 2.0 comment: 14.3.2 Conformance of SMIL 2.0
> Basic Documents]
> 
> 
> Hi, 
> 
> I have tried to summarize the things I don't understand:
> 
> * 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?
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.

> * As a language designer I would like to integrate SMIL 2.0 
> modules with my own language (Another common use case, I 
> think). How do I declare, using namespaces and 
> 'systemRequired' attribute, that the document consists of 
> both SMIL modules and my own modules? Where do I specify 
> _how_ the modules are integrated?
You do that in the profile document for the language you design, as well as
the DTD and/or XML Schema for that language. Using these means, you can
specify exactly what modules are legal syntax in your profile. You still
need to use the profile document to specify semantics that differ from or
are not defined in the smil 20 modules.

> * How can, for example, a mobile phone indicate to the server 
> that it supports only SMIL Basic modules, 
This is a CC/PP thing, and orthogonal to SMIL

>> and sending down a 
> SMIL document with other modules is a waste of bandwidth and 
> will not be played as expected by the author; everything but 
> the basic modules will be ignored. I consider it an Error if 
> a mobile phone receives an advanced SMIL document and can 
> play only a fraction of the content - it cannot be what the 
> author expected. 
Like we said above, you can always create your own profile based on smil
basic, and only allow your player to play those. One can either use the smil
doctype and our scalability mechanism, or create a distinct doctype based on
smil basic and the smil modules. It is not legal to usurp the smil doctype
and place additional non-smil 2.0 restrictions on the document (as opposed
to the player). One can't have it both ways.
 
> * 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? 
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. Once again, you
can't have it both ways.

> 
> Peter
> 
> 
> > -----Original Message-----
> > From: Kenichi Kubota [mailto:kuboken@isl.mei.co.jp]
> > Sent: den 14 mars 2001 10:20
> > To: Peter Stark (ECS); 'Cohen, Aaron M'; Philipp Hoschka;
> > www-smil@w3.org
> > Subject: RE: [Fwd: SMIL 2.0 comment: 14.3.2 Conformance of SMIL 2.0
> > Basic Documents]
> > 
> > 
> > Hi Peter,
> > 
> > At 09:12 01/03/14 +0100, Peter Stark (ECS) wrote:
> > >Hi Aaron,
> > >
> > >I note that the SYMM group has taken a very different approach to 
> > >conformance and interoperability than, for example, the HTML group.
> > >
> > >Aaron writes:
> > > >
> > > > The most straight forward way to declare that a document can
> > > > be played by a
> > > > smil basic player is:
> > > >
> > > > <smil xmlns="http://www.w3.org/2001/SMIL20/WD/Language"
> > > >       
> xmlns:basic="http://www.w3.org/2001/SMIL20/WD/HostLanguage"
> > > >       systemRequired="basic">
> > > > ...
> > > > </smil>
> > > >
> > >
> > >So there is no way for the developer to check whether the document 
> > >includes only the SMIL Basic modules. There is no DTD/Schema 
> > for SMIL 
> > >Basic, that includes only the basic modules.
> > 
> > The example which Aaron writes above means that the 
> document includes
> > only the SMIL Basic modules.
> > Checking with DTD/Schema, I think, may not work.
> > SMIL has many powerful functionality and only modularization 
> > at element
> > level, I think, may not cover whole restrictions of basic players.
> > So we can describe them as authoring guidelines.
> > 
> > Another reason is that SMIL has the ContentControl.
> > For authoring tool convenience, the document can be also 
> described as:
> >    <smil xmlns="http://www.w3.org/2001/SMIL20/WD/Language"
> >          xmlns:advanced="http://advanced.profile.somewhere"
> >          
> xmlns:basic="http://www.w3.org/2001/SMIL20/WD/HostLanguage">
> >    ...
> >    <switch>
> >       <par systemRequired="advanced">
> >         ...
> >       </par>
> >       <par systemRequired="basic">
> >          ....
> >       </par>
> >     </switch>
> >    ...
> >    </smil>
> > 
> > Here is one document of SMIL for both of advanced players and 
> > basic players!
> > There is no need of DTD/Schema for Basic at a XML document level.
> > 
> > >And since the SMIL media type does not indicate what 
> > modules/profiles the 
> > >client supports, the server can do nothing more than serving 
> > the same SMIL 
> > >document to all types of SMIL clients.
> > 
> > There is a warm SMIL family with the media type "application/smil".
> > SMIL itself has content control mechanisms as the above.
> > Server can serve it in trimming the document with "systemRequired".
> > 
> > Philipp, how is the status of "application/smil"?
> > Has it been already registered?
> > 
> > >I am also worried about the following statement:
> > > >
> > > > We expect that other standards bodies will build profiles
> > > > starting with the
> > > > smil basic scalability framework and the host language
> > > > conformance set.
> > > > These profiles can have their own doctype/namespace/dtd and
> > > > make documents
> > > > written in them directly identifiable as such.
> > > >
> > >
> > >If, for example, the WAP Forum or the 3GPP would define 
> > their own SMIL 
> > >profile using only SMIL 2.0 modules, should they also define 
> > their own XML 
> > >namespace? I hope the answer is no.
> > 
> > I think they can define it and they can use it like the 
> above example.
> > Aaron, Michelle, do we agree?
> > 
> > Best regards,
> > Kenichi Kubota @ Panasonic
> > 
> > 
> > >regards,
> > >
> > >Peter
> > 
>

Received on Wednesday, 14 March 2001 12:31:10 UTC