Video quality in next generation mobile networks — Perception of time-varying transmission

Next Generation Mobile Networks (NGMNs) provide an all-IP wireless platform for multimedia service delivery. The integrated communication system creates new perspectives for wireless video distribution and quality provisioning. Depending on the mobility patterns of the nomadic users, the link layer characteristics may rapidly change. Furthermore, mobility and service adaptation events like network handovers, video bit rate switching, or codec changeovers, may affect the user perception. Provisioning “always best connected” video services requires a thorough knowledge of video quality perception in NGMNs. In this paper, we address this problem. A subjective test including 50 NGMN conditions has been carried out. They were arranged in groups to assess the impact on perceived quality of 1) the access technology and network handover, 2) video codecs and codec changeover, 3) video bit rate and bit rate switching, and 4) to provide guidelines for packet loss adaptation. We could identify the perceptual bottlenecks of the future wireless communication and are able to propose perceptual guidelines for mobility management. In this way, this paper contributes to the service quality improvement of future wireless communications.