- From: Tayeb Lemlouma <Tayeb.Lemlouma@inrialpes.fr>
- Date: Tue, 23 Apr 2002 12:35:11 +0200
- To: "Butler, Mark" <Mark_Butler@hplb.hpl.hp.com>
- Cc: <w3c-di-wg@w3.org>, <w3c-ccpp-wg@w3.org>, <www-mobile@w3.org>
Hi Mark, I read you report on capability classes and found it very interesting. Here are some comments: - Content adaptation based on XSLT is interesting in structural transformation (e.g. XHTML to WML, HTML to SMIL, etc.) but there is another kind of adaptation which is very important and can be seen as the complementary of structural transformations which is media resources transformation. A simple example to see that is the transformation of HTML to WML. In this case, to achieve the adaptation properly, media resources used inside the original document (HTML) must also be transformed, for instance JPEG to WBMP images. - The initial definition of classes of devices is benefit but not sufficient.The number of the combination of ATOMIC characteristic properties may be infinite. This implies that the classes definition will, in all the cases, negligee some kind of devices. Further more, we can't envisage all the possible kind of constraints of the existing set of devices and also for future devices. - Devices may be very different, or have just some little difference in characteristics properties. This underlines the problem of the abstraction level used in the definition of the capability classes. Note that due to just one difference of atomic characteristics between two devices, the server may have to deliver two contents which are completely different. - Axes of negotiation depend to the detailed level of the user constraints declaration and the capability of the server either by available XSLT style sheets or other adaptation methods (scripts, programs, etc.). The number of the required adaptation methods (XSLT sheets for instance) depends so to how methods were designed. In the case of XSLT we can have parameterable and composite style sheets which can takes into account more than one predefined device class. - A little comment concerning Section 4: I think that the conditional "lessthan", for boxes, is not the opposite of the "greaterthan" conditional (if B1 isn't lessthan B2, this doesn't implies that B2 is greaterthan B1). This may causes that there is a set of boxes that are not comparable and consequently we can negligee some class of devices using the proposed conditional. ---------- Tayeb Lemlouma http://www.inrialpes.fr/opera/people/Tayeb.Lemlouma/index.html Opera project National Research Institute in Computer Science and Control (INRIA Rhône-Alpes, France ) Office B213, phone (+33) 04 76 61 52 81, Fax (+33) 04 76 61 52 07. ----- Original Message ----- From: "Butler, Mark" <Mark_Butler@hplb.hpl.hp.com> To: <tayeb.lemlouma@inrialpes.fr> Sent: Monday, December 10, 2001 6:21 PM Subject: FW: CC/PP > > > Hi Tayeb, > > > > I have just exchanged emails with Nabil Layaida. He said to contact you. I > > have been reading you papers on CC/PP and I found them interesting. I am > > also working on CC/PP - my work is available at > > http://www-uk.hpl.hp.com/people/marbut/. > > Specifically I have a server-side CC/PP implementation called DELI I have > > released on an open-source basis that may be of interest. > > > > Incidentally, just a minor point, there are a number of mistakes in your > > CC/PP on page 9 of "A Framework for Media Resource Manipluation in > > Adaptation and Negotiation Architecture". > > > > - You need to declare a namespace for your elements. This could be > > prefixed or global, although my preference would be for a prefixed > > namespace. > > > > - The expression > > > > heightxwidth<=12000Bytes > > > > is not valid XML. > > > > - You need to add the additional lines > > > > </ccpp:component> > > </rdf:Description> > > </rdf:RDF> > > > > to the end of the profile. > > > > As I say these are very minor points but it would be good to get the CC/PP > > correct - if in doubt try checking profiles using the RDF validator at > > http://www.w3.org/RDF/Validator/. > > > > best regards > > > > Mark H. Butler, PhD > > Research Scientist > > HP Labs Bristol > > >
Received on Tuesday, 23 April 2002 07:52:15 UTC