Année 2000


Directeurs de thèse : Cécile Roisin - Nabil Layaída

Equipe: projet Opéra - Inria Rhône-Alpes

Titre : Architecture de négotiation et d'adaptation de services multimédia dans des environnements hétérogènes

Mots-clé : négociation, adaptation, document multimédia, profile client, profile de document

<Version anglaise>


OPERA group has a long experience on multimedia technology and more precisely on the development of user-friendly tools for the editing and management of complex multimedia documents. The main contributions are presented through academic results (scientific papers and theses, see references below) and through research prototypes in which several approaches for authoring and rendering multimedia documents have been experimented (Thot-editor, Madeus, Smil-Editor, MHML-Editor, Kaomi toolkit).

More recently Opera members have started some studies on content adaptation to the effective context of the presentation such as the end-system and the user preferences or constraints. One of these studies has been performed in the context of the previous collaboration with Alcatel. In another study [1], a general framework for document production through the specification of a document presentation model has been developed. In this framework, a document is not only considered through its final presentation but also through a more semantical representation covering its class and its content. For that purpose we have defined a multimedia document model called Madeus model which aims to represent a multimedia scenario through its different dimensions: logical, temporal, spatial, etc. The presentation generation is achieved through a set of transformation and decoration steps of the initial data (XML specification for instance). This approach will allow to take into account the increasing diversity of visualisation and interaction devices: PDA (Personal Device Assistant), cellular phone, workstation, microphone, etc.

The work proposed here will be based on this document production architecture in order to take advantages on existing solutions (for the transformation processes, for the presentation model, etc.).

This study will be done in the context of a collaboration between Opera group and the 'Service Knowledge and Communication Technologies' group of CRC Services. It can be noticed that adaptation problem is being addressed with a different focus by the two teams: Alcatel is interested in Abstract User Interface Language (high level specification for user and terminal profiles) while Opéra aims at providing transformation of XML documents for the generation of multimedia presentations. So both teams have a common interest for merging these complementary backgrounds and propose new solutions for the negotiation between clients and servers in order to provide service adaptation.

[1] Muriel Jourdan, Cécile Roisin, and Laurent Tardif, A Scalable Toolkit for Designing Multimedia Authoring Environments, Special number, 'Multimedia Authoring and Presentation: Strategies, Tools, and Experiences' of Multimedia Tools and Applications Journal, Kluwer Academic Publishers, 2000.


In order to offer service providers the ability to create and deploy new services in an efficient and timely manner, a service should be preferably written once and then (semi-)automatically adapted according to its deployment context. The latter service adaptation process should will take into account the needs of different terminal types, the requirements of a page/service, the preferences of a user, characteristics of the network, etc. XML was chosen as base technology as it already offers a clean separation between data and presentation. The adaptation process targets existing formats such as WML, VoiceXML and XHTML. Many W3C related activities are much related to this topic. For example, CC/PP (Composite capability / Preference Profiles) is specifically looking at content negotiation mechanisms.

The goal of this work is to provide integrated solutions for service adaptation in a web environment. Several techniques will be studied and experimented with a special interest of their integration in a more general framework:

These studies will be experimented through a case study with a focus on the compatibility between the Alcatel specifications and framework/architecture.