Towards context-aware interactive Quality of Experience evaluation for audiovisual multiparty conferencing

In modern video conferencing services, just as in commonvideo delivery, most of the resource optimization is taken careof in the codec layer. Modern codecs like H.264 use detailedperceptual models to optimize the data reduction in way that itis least noticed by us. Already early evaluations oftelecommunication systems could establish that there aredifferent thresholds for a good quality depending on thesituation. It is further known that subjective quality perceptionsvary from user to user. But the space of user and context factorsis still largely unexplored. To gain insight in which parametersare key in differentiating quality perception, we need to explorethe interaction in different situations while keeping a tightcontrol over the system parameters. In this paper we explorehow clustering participants by their interaction or ratingbehavior can reveal subgroups that show significantly differentperception of the QoE delivered by the same videoconferencingsystem. While for a cluster of users we find video quality toinfluence other QoE dimensions such as audio, for anothercluster this is not the case. We explore whether this effect is dueto conversational dynamics (contextual factor) or individualpreferences (user factor) and discuss what this would mean forthe design of future video-conferencing systems, that want todynamically adapt to situation and participants.