Mechanisms for QoE optimisation of video traffic: a review paper

Transmission of video traffic over the Internet has grown exponentially in the past few years with no sign of waning. This increasing demand for video services has changed user expectation of quality. Various mechanisms have been proposed to optimise the Quality of Experience (QoE) of end users’ video. Studying these approaches are necessary for new methods to be proposed or combination of existing ones to be tailored. We discuss challenges facing the optimisation of QoE for video traffic in this paper. It surveys and classifies these mechanisms based on their functions. The limitation of each of them is identified and future directions are highlighted

Prediction and Transmission Optimization of Video Guaranteeing a Bounded Zapping-Delay in DVB-H

Zapping-delay is an important factor contributing to the quality-of-experience (QoE) of any multimedia service; the longer the zapping-delay, the worse is the QoE. Therefore, for a good QoE, it is necessary to bind zapping-delay within acceptable bounds. Coded video uses a motion compensated prediction structure that contributes to the zapping-delay. In DVB-H, zapping-delay is further increased because of the time-sliced burst transmission architecture. Hence, any attempt to bind zapping-delay must consider both the prediction structure of coded video, as well as the time-sliced transmission architecture of DVB-H. This paper analyzes prediction structure of video as binary relations generating a prediction graph. Reachability concepts of graph theory are then applied to construct binary valued indicator functions. These indicator functions inform about the reception, decoding, and play-out states of each access-unit in the video sequences. zapping-delay is studied by dissecting the components that it is composed off. Conditions for minimizing each of them individually, while the final zapping-delay does not exceed a known bound, is found. Emphasis is also laid on gradual quality enhancement after the display of the new program has started