Ontology-based multimedia access in virtual learning environment

Virtual learning environments (VLEs), such as virtual conferences, virtual seminars and virtual classrooms, enhance learning experience by supporting learning at flexible time and locations. With advances in computation capacity, network bandwidth, and information storage, the volume of multimedia learning materials increase dramatically in recent years. However, we note that current keyword-based multimedia access techniques in VLEs have several general limitations and are not effective in locating multimedia learning materials. We argue that the effectiveness of multimedia access in VLEs depends on how multimedia-learning materials are annotated and how integrated access across domains is supported. In this paper, we propose an ontology-based multimedia access platform for VLEs that consists of two modules: integrated multimedia annotation module and ontology-based multimedia access module. Integrated multimedia annotation module extracts various annotations from captured individual multimedia objects and generates integrated multimedia annotation data based on temporal, spatial, and semantic relationships among them. Ontology-based multimedia access module integrates domain knowledge into multimedia access and provides an interface that domain experts can use to access multimedia learning materials. Based on the proposal, Ontology-based Multimedia Access Platform for virtual conference (OMAP) is implemented. This platform provides rich and multilevel annotation data and integrates Gene Ontology into multimedia access process. The implementation involves various techniques in ontology, image and video processing, multimedia authoring, database, and programming.