Content-based retrieval has been identified as one of the most challenging problems, requiring a multidisciplinary research among computer vision, information retrieval, artificial intelligence, database, and other fields. In this paper, we address the specific aspect of inferring semantics automatically from raw video data. In particular, we present the Cobra video database management system that supports the integrated use of different knowledge-based methods for mapping low-level features to high-level concepts. We focus on dynamic Bayesian networks and demonstrate how they can be effectively used for fusing the evidence obtained from different media information sources. The approach is validated in the particular domain of Formula 1 rac...