Energy-aware system design for wireless multimedia

Abstract

In this paper, we present various challenges that arise in the delivery and exchange of multimedia information to mobile devices. Specifically, we focus on techniques for maintaining QoS to end-user multimedia applications (e.g. video streaming, multimedia conferencing) while maximizing device lifetimes. In order to cope with the resource intensive nature of multimedia applications (in terms of computation, bandwidth and consequently power) and dynamic congestion levels in wireless networks, an end-to-end approach to QoSaware power optimization is required. We discuss the trend towards such an integrated approach that couples the architectural, OS, middleware and application layers to achieve both user experience and device energy gains. We conclude with a discussion of tools for integrated system design and testing that will aid in rapid deployment of wireless multimedia. MotivationLimiting the energy consumption of low-power mobile devices has become an important research objective in recent years. The capabilities of these devices are limited by their modest sizes and the finite lifetimes of the batteries that power them. As a result, minimizing the energy usage of every component (e.g. CPU, network card, display, architecture etc.) in such devices remains an important design goal and continues to pose significant challenges. On the other hand, rapid advances in processor and wireless networking technology are ushering in a new class of multimedia applications (e.g. video streaming/conferencing) for mobile handheld devices. Multimedia applications have distinctive Quality of Service(QoS) and processing requirements which tend to make them extremely resource-hungry. Moreover, the device specific attributes(e.g form factorof handhelds) significantly influence the human perception of multimedia quality. As a result delivering high quality realtime multimedia content to mobile handheld devices remains a difficult challenge.These issues have been aggressively pursued by researchers and numerous interesting power optimization solutions have been proposed at various cross computational levels -system cache and external memory access optimizations [2,11], dynamic voltage scaling(DVS) [18,6] of the CPU, dynamic power management of disks and network interfaces(NICs) [7,

Holistic design and caching in mobile computing

“…Our proposal is more consistent with the view that many MPEG implementations of video data are "un-cacheable" [20]. Most data-dominated multimedia applications do not use their cache efficiently [21], largely due to the streaming nature of video, which our approach avoids.…”

Seamless Multimedia Delivery Within a Heterogeneous Wireless Networks Environment: Are We There Yet?

“…Another technique that explores the energy saving in multimedia streaming is brightness compensation [158], [159], [160]. The authors in [158], [159] propose the use of a proxy server that performs on-the-fly transcoding and dynamic adaptation of the video content (brightness compensation) based on the feedback from the client.…”

“…The authors in [158], [159] propose the use of a proxy server that performs on-the-fly transcoding and dynamic adaptation of the video content (brightness compensation) based on the feedback from the client. The proxy server will send back the control information to the client middleware which will change its system parameters (e.g., operating backlight level) accordantly.…”

Reconfigurable Security Primitive for Embedded Systems

“…In this study, we have defined very simple policies as the goal was mainly to demonstrate the advantages of such a solution instead of focusing on new policy algorithms. However, for interested readers, there are several papers that have been published about performance policy [15] [16].…”