Energy-aware video streaming on smartphones

Abstract—Video streaming on smartphone consumes lots of energy. One common solution is to download and buffer future video data for playback so that the wireless interface can be turned off most of time and then save energy. However, this may waste energy and bandwidth if the user skips or quits before the end of the video. Using a small buffer can reduce the bandwidth wastage, but may consume more energy and introduce rebuffering delay. In this paper, we analyze the power consumption during video streaming considering user skip and early quit scenarios. We first propose an offline method to compute the minimum power consumption, and then introduce an online solution to save energy based on whether the user tends to watch video for a long time or tends to skip. We have implemented the online solution on Android based smartphones. Experimental results and trace-driven simulation results show that that our method can save energy while achieving a better tradeoff between delay and bandwidth compared to existing methods. I

Large-scale sensor-rich video management and delivery

Ph.DDOCTOR OF PHILOSOPH

Video streaming over cooperative wireless networks

We study the problem of broadcasting video streams over a Wireless Metropolitan Area Network (WMAN) to many mobile devices. We propose a cooperative network in which several elected mobile devices share received video data over a Wireless Local Area Network (WLAN). The proposed system significantly reduces the energy consumption and the channel switching delay concurrently. We design a distributed leader election algorithm for the cooperative system and analytically show that the proposed system outperforms current systems in terms of energy consumption and channel switching delay. Our experimental results from a real mobile video streaming testbed show that the proposed cooperative system is promising because it achieves high energy saving, significantly reduces channel switching delay and uniformly distributes load on all mobile devices. Furthermore, we complement our empirical evaluation with a trace driven simulator to rigorously show the viability of the proposed cooperative system