Multimedia ontology based computational framework for video annotation and retrieval

Ontologies are defined as the representation of the semantics of terms and their relationships. Traditionally, they consist of concepts, concept properties, and relationships between concepts, all expressed in linguistic terms. In order to support effectively video annotation and content-based retrieval the traditional linguistic ontologies should be extended to include structural video information and perceptual elements such as visual data descriptors. These extended ontologies (referred in the following as multimedia ontologies) should support definition of visual concepts as representatives of specific patterns of a linguistic concept. While the linguistic part of the ontology embeds permanent and objective items of the domain, the perceptual part includes visual concepts that are dependent on temporal experience and are subject to changes with time and perception. This is the reason why dynamic update of visual concepts has to be supported by multimedia ontologies, to represent temporal evolution of concepts.