This PhD work presents an innovative sernantic model for an audiovisual information
retrieval system, which better covers the user's requirements in an integrated TV news
production environment. This model exploits an interchangeable description format ( N N
Schema) that we proposed in order to integrate a rich set of required TV news
information. In this work, we firstly propose a semantic model for the retrieval of audiovisual
information, called the Semantic Views Model. This model takes into account various
users' viewpoints from which they search for audiovisual content in the context of their
activities. We propose two different modes to retrieve audiovisual content: querying and
browsing, and strategies to integrate these two modes in order to improve the interactive
retrieval. To facilitate querying we propose a high-level query language following the
Semantic Views Model, called Semantic Views Query Language (SVQL). Moreover, to
allow browsing and playing we define the Semantic Views Hypermedia Model.
We secondly propose N N Schema, a TV news description schema based on MPEG-7,
which allows the representation of TV news information in an environment that integrates
the three processes of production, archiving, and retrieval. The use of NN Schema
improves al1 the three so-called processes by allowing an effective information exchange
between them and also with external applications.
To validate Our proposed methodology we set up the COALA experimental project. COALA
provides various tools for both indexing and retrieval of audiovisual programs at the TSR
broadcasting Company. The design of these tools is based on the application of the
Semantic Views Forma1 Model and the WN Schema specification. These principles
succeeded in overcoming the challenges related to the complexity of the users'
requirernents and the richness and diversity of information resources.