Subjective assessment of fairness among users in multipoint communications

ABSTRACT

By subjective assessment, this paper investigates the influences of network latency and packet loss on the perception of fairness among users in multipoint communications where the users have a conversation with each other by using live voice and video. We also assess the fairness in the case where we use users' avatars constructed by computer graphics (CG) instead of video. Assessment results show that most of subjects perceive unfairness when the difference in network latency between two terminals exceeds approximately 100 ms, or when the difference in packet loss rate becomes larger than around 30 %. Furthermore, we demonstrate that we can estimate the value of MOS with high accuracy from the difference in network latency and packet loss rate.

REFERENCES

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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)

General Terms:
Experimentation, Human Factors, Performance

Keywords:
avatar, multipoint communications, networked virtual environments, subjective assessment, video, voice