Achieving effective floor control with a low-bandwidth gesture-sensitive videoconferencing system

ABSTRACT

Multiparty videoconferencing with even a small number of people is often infeasible due to the high network bandwidth required. Bandwidth can be significantly reduced if most of the advantages of using full-motion video can be achieved with low-frame-rate video; unfortunately, the impact of low-frame-rate video on communication is relatively unexplored. We implemented a multiparty videoconferencing system that supports full-motion video, low-frame-rate video where the video is updated only once every few seconds, and a hybrid scheme where full-motion video is transmitted when the system detects that a user is making a gesture and low-frame-rate video is transmitted at all other times. We studied people using our system for small-group discussions and found that low-frame-rate video limited people's ability to request to speak or judge when to stop speaking. The hybrid scheme, conversely, was as effective as full-motion video for floor control, resulting in a similar number of speaker changes, while using only ten percent of the bandwidth.

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INDEX TERMS

Keywords:
floor control, frame rate, multiparty videoconferencing