A QoE study of different stream and layout configurations in video conferencing under limited network conditions

One particular problem of QoE research in video conferencing is, that most research in the past concentrated on one-to-one video conferencing or simply video consumption. However, video conferencing with two people (one-to-one) and within a group (multi-party) is different. Particularly, limitations of one participant might have an effect on the QoE of the whole group. This possible effect however is not well studied. Therefore, this paper aims to better understand the impact of individual limitations towards the groups QoE. To do so, we show a study about different video stream configurations and layouts for multi-party conferencing in respect to individual network limitations. For this, we conduct a user study with 20 participants in 5 groups, in a semi-controlled setup. Such a setup, combines supervising participants locally while still using our software infrastructure deployed in the internet. Furthermore, we use an asymmetric experiment design, by putting every participant under a different condition, as this proposes a more realistic scenario. Within our study, we look at three different factors: layout, video quality and network limitations. To foster conversation between participants, the group engaged in a discussion about different survival questions. Our findings show that packet loss and the resulting distortions have a greater impact on the QoE as reducing the video quality by its resolution. Furthermore, our findings indicate that participants are more satisfied in a visually equal layout (showing participants in a similar size) and a more balanced stream configuration.