Metadata, intelligent indexing, and repository management for multimedia digital libraries

Metadata represent the vehicle by which digital documents can be efficientl y indexed and retrieved. The need for such kind of information is particula rly evident in multimedia digital libraries, which store documents dealing with different types of media (text, images, sound, video). In this context , a relevant metadata function consists in superimposing some sort of conce ptual organization over the unstructured information space proper to these digital repositories, in order to facilitate the intelligent retrieval of t he original documents. To this purpose, the usage of conceptual annotations seems quite promising. In this paper, we propose a two-steps annotation ap proach by which conceptual annotations, represented in NKRL (Narrative Know ledge Representation Language) [20, 21], are associated with multimedia doc uments and used during retrieval operations. We then present how documents and metadata can be stored and managed on persistent storage.