User Interactions with Multimedia Repositories using Natural Lan- guage Interfaces: an Architectural Framework and its Implementation

We present a generalized architectural framework for constructing and using natural language interfaces for interactions with multimedia repositories. The framework can take advantage of user profiles to rank the resulting queries from the natural language expressions. This to avoid or reduce the disambiguation overhead, meaning the elimination of the possible senses that can be assigned to a word in the discourse in a particular domain. The architecture for the disambiguation procedure is based on a combination of classical search techniques and a constrained spreading activation algorithm, an algorithm for searching information in networks like ontologies. We calculate the strength of relations between concepts in ontologies by assigning a weight value. The constrained spreading activation algorithm used is controlled by heuristic rules that are obtained from the search mechanism applied in the ontology. We describe the implementation of this framework for supporting interactions with a multimedia repository, described with the MPEG-7 MDS (Multimedia Description Schemes) structures.