CIRCE: Content-Based and Semantic Multimedia Indexing and Retrieval in Collaborative Environments, General Secretariat for Research and Technology, Hungary - Greece, Joint Research and Technology Programmes, 2004 - 2006. Objective of the collaboration will be the definition, specification and implementation of an architecture for the content-based and semantic indexing and retrieval of visual information, and the sharing of the knowledge acquired during retrieval by different users.