A novel method for video event analysis and description based on the knowledge domain has been put forward in this paper. Semantic concepts in the context of the video event are described in one specific domain enriched with qualitative attributes of the semantic objects, multimedia processing approaches and domain independent factors: low level features (pixel color, motion vectors and spatio-temporal relationship). In this work, we consider one shot (episode) in the Billiard Game of video as the specific domain to explain the process of video event detection In addition, our another main contribution is exploiting the video object ontology to map the MPEG-7?s high-level descriptors to low level features descriptors which have been defined in the MPEG?s logical structure.