ABSTRACT
Internet multimedia communication, such as video-and audio-on-demand, video conferencing, and distance e-Learning, let us experience multimedia at the desk. Video mobile phones will, in the near future, let us create short video clips, send these videos to a partner mobile phone or to a personal database at home, and play videos that we receive from a friend. These systems are peer-to-peer: terminal clients become servers and vice versa. To realize the vision of peer-to-peer multimedia systems with heterogonous terminals, many technical problems need to be solved. These problems concern all layers of a multimedia system; for instance, the multimedia communication system, distributed control system, and storage and retrieval systems. Strongly related to this vision of peer-to-peer multimedia systems is the enhancement of a multimedia system with metadata. Metadata describe the multimedia content and could be semantic descriptions, such as which persons appear in a video clip; information on color characteristics of a video, such as the dominant color in an image; or information on how a video might be adapted if resources become rare.
