In this paper, we address the problem of representing domain knowledge for situation awareness in a security application. While ontologies are appropriate for describing taxonomical knowledge, they cannot express more complex knowledge such as entailments. In this paper, we describe how domain knowledge can be encoded through OWL ontologies and SWRL rules in order to reason about the entities and their interactions in a surveillance application. We describe how events can be described through ontologies and how video sequences can be annotated using the MPEG-7 standard.
