Designing a large-scale video chat application

ABSTRACT

Studies of video conferencing systems generally focus on scenarios where users communicate using an audio channel. However, text chat serves users in a wide variety of contexts, and is commonly included in multimedia conferencing systems as a complement to the audio channel. This paper introduces a prototype application which integrates video and text communication, and describes a formative evaluation of the prototype with 53 users in a social setting. We focus the evaluation on bandwidth and view navigation requirements in order to determine how to better serve users with video chat, and discuss how the findings from this evaluation can inform the design of future video chat applications. Bandwidth requirements are evaluated through user perceptions of video delivered using three different bandwidth schemes. For view navigation, we examine a system that automatically switches the video focus to the current "chatter", instead of requiring users to navigate manually to find the video steam they are interested in viewing.

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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.4 INFORMATION SYSTEMS APPLICATIONS
      H.4.3 Communications Applications
          Subjects: Computer conferencing, teleconferencing, and videoconferencing

Additional Classification:
  H. Information Systems
  H.5 INFORMATION INTERFACES AND PRESENTATION (I.7)
      H.5.m Miscellaneous

General Terms:
Design, Experimentation, Human Factors, Performance

Keywords:
bandwidth sharing, chat, collaboration, video conferencing