Mobile Real-Time Collaboration for Semantic Multimedia

Advanced mobile applications that enable new ways of interaction with digital objects become increasingly important for on-site professional communities. These new ways of interaction, e.g. in Mobile Augmented Reality (MAR) via position and 3D movement, are real needs for fieldwork domains such as cultural heritage management and the construction industry. In addition, on-site professional communities generate shared knowledge bases with multimedia content and semantic annotations through collaboration. However, current MAR applications lack real-time collaboration features. In practice, blending multimedia semantics in mobile real-time collaboration is challenging due to the limitations of mobile devices, the lack of mature dedicated designed communication infrastructures and the constraints of the remote environments. This paper presents a mobile real-time collaboration system for semantic multimedia annotations with augmented reality features. We use XMPP as a real-time protocol for the secure, scalable and interoperable processing of XML-based semantic multimedia metadata described in MPEG-7. Our prototype was evaluated in the digital documentation of historical sites for cultural heritage management. The evaluation results indicate potential for increased productivity and enhanced mutual awareness in on-site professional communities.