Content-adaptive display power saving in internet mobile streaming

Abstract

Backlight scaling is a technique proposed to reduce the display panel power consumption by strategically dimming the backlight. However, for Internet streaming to mobile devices, a computationally intensive luminance compensation step must be performed in combination with backlight scaling to maintain the perceived appearance of video frames. This step, if done by the CPU, could easily offset the power savings via backlight dimming. Furthermore, computing the backlight scaling values requires per-frame luminance information, which is typically too energy intensive to compute on mobile devices.In this paper, we propose Content-Adaptive Display (CAD) for Internet mobile streaming. CAD uses the mobile device's GPU rather than the CPU to perform luminance compensation at reduced power consumption. Backlight scaling schedule is computed using a more efficient dynamic programming algorithm than existing work. We implement CAD within an Android app and use a Monsoon power meter to measure the real power consumption. Experiments are conducted on more than 470 randomly selected YouTube videos, and results show that CAD can effectively produce power savings.

Toward Cost-Effective Mobile Video Streaming through Environment-Aware Watching State Prediction

“…Video codecs can be optimized to reduce power consumption during encoding, decoding, and display [5]. For mobile tasks that consume huge amounts of power such as illumination, Liu et al [6] presented content-adaptive display (CAD), to transfer the load of luminance compensation for videos from the mobile device’s CPU to the GPU to produce power savings. A decision algorithm to select the most efficient video codec according to its chroma characteristics was introduced by Jiménez et al [14] to save bandwidth.…”

“…Therefore, setting our sights on the data download level, this paper focuses on data download strategies to provide cost-effective video streaming. Several studies have already examined cost-effective mobile video streaming, focusing on providing bandwidth or energy saving schemes [3,4,5,6,7,8,9]. Specifically, some researchers considered user behavior and proposed optimized cost-effective strategies [10,11,12].…”