Rapid development of network technologies has led to a proliferation of networked video applications, making efficient and effective assessment of the related Quality of (user) Experience (QoE) an acute need. In literature, there has been a non-uniform view of Quality of Service (QoS) and therefore the concept of QoE is introduced to avoid the confusion. The difference between QoS and QoE is first clarified in this paper. Then QoE metrics in the current standardized framework for Internet Protocol (IP) based streaming applications in 3G networks, i.e., 3GPP PSS, are introduced. Moreover, objective QoE evaluation for networked video is addressed in respect to perceived video quality, which can be categorized into the parametric-planning model, parametric packet-layer model, parametric bit-stream-layer model, media-layer model, and hybrid model. The related characteristics, state-of-the-art, standardization process and key patents are respectively reviewed.
Keywords: QoE, QoS, video quality, Networked Video Services, 3G networks, Codec Information, Codec Bit-Rate, Corruption Duration Metric, RTP (Real-time Transport Protocol), Jitter Duration