DMTS - A DISTRIBUTED MULTIMEDIA TELEWORKING SYSTEM

Multimedia systems combine a variety of information sources, such as v oice, graphics, animation, images, and full-motion video, into a wide range of applications. The paper initially categorizes existing multim edia applications into three classes: noninteractive-oriented, interac tive-oriented client-server-based, and interactive-oriented peer-party -based. In particular, the paper examines interactive-oriented applica tions and provides an in-depth survey of the media synchronization pro blem for the design of these applications. The paper then presents our prototyping system, called the Distributed Multimedia Teleworking Sys tem (DMTS), which allows two or more remote systems in collaboration t o access and modify multimedia data through a network in a fully synch ronous fashion. The system has been developed over TCP/IP and an FDDI network, using an XVideo D/A card. The media supported by DMTS include text, graphics, voice, and video. DMTS employs a master-slave collabo ration model to maintain the coherence of the text and graphics data b eing simultaneously modified. Moreover, DMTS also adopts effective mec hanisms to reduce skew (asynchrony) and jitter delays between video an d voice streams. Finally, the paper demonstrates that DMTS achieves a maximum throughput of 13 frames per second, and reveals that the throu ghput bottleneck resides in the hardware capture and D/A processing of video frames.