Research & Design Of Visual Collaboration System Based On RTMP & SIP

With the development of multimedia and network technology, visual collaboration is playing a more important role in education, research and communication nowadays. Traditional visual conference system is based on H.323 protocol, which requires special hardwares. Such solutions are not qualified for modern convenient web applications. On the other hand, some software solutions may be inconvienient to install heavy-weight client, or inadaptable to voice contact by phone.After comparison on RIA technology, visual collaboration system adopts Flash as the user interface to avoid extra prerequisites. A research on VoIP helps to bridging voice to SIP server in order to achieve more accessibility amony PC users and phone users. The video transmitted by RTMP via Red 5 has a codec as Screen Video BitStream which lowers the network bandwidth utilization.A screen share whiteboard is designed for further collaboration. The video is based on dynamic screen content, above which the whiteboard enhances the richness among multiple users without the complexity of resolving static files. Flex SharedObject guarantee the real-time message update.In functionality test, the system can publish and play the screen share video smoothly. The quality of voice chat is good. And the whiteboard is quite practical. When tested with heavy load and poor network, the performance is reasonable, and qualified for daily usage.