Real-time camera control for videoconferencing over the Internet

In videoconferencing, which means a small group meeting, interactive distance learning and so on, there is a requirement to get required video at a remote site freely and easily by local control of a remote camera. However, there are some delays between camera control operations at a remote site and actual video images displayed on a local screen. Delays are caused by network delays between sender and receiver and by video compression delays. To operate a remote camera interactively, a user must control the device considering these delays. We describe these problems in the case of videoconferencing and develop a real time camera control system to solve them. Our approach does not involve reducing delays but showing delays for users by some indication under the current environment. With our proposed system, a user can easily operate a remote camera without considering network and compression delays. We use a new camera control protocol designed by us in our system. We also describe a prototype system and its evaluation used in distance learning.