LGC-DVS: Local Gamma Correction-Based Dynamic Voltage Scaling for Android Smartphones With AMOLED Displays

Abstract

Recently, the use of active matrix organic light emitting diode (AMOLED) displays is increasing for smartphones which have been widely used and their battery lifetime is very important for users. Due to frequent interactions between users and smartphones, the power management of AMOLED displays is crucial. To this end, dynamic voltage scaling (DVS) is most effective and a lot of studies on it have been made. However, no work of DVS on smartphones with AMOLED displays can be found in the literature. In this paper, we propose the first practical DVS scheme for AMOLED displays on Android smartphones, aiming both human visual system (HVS)-awareness and high power saving. It combines automated battery-aware DVS with local gamma correction and effective smoothing using a novel metric which can evaluate the balance between power saving and HVS-awareness from a user study. In extensive experiments with an implementation of an Android platform, the proposed scheme saves power consumption by up to 62% and extends battery lifetime by about 15% over a normal mode. Moreover, it achieves better HVS-awareness as well as better power saving than the power-saving mode in a smartphone, which restricts some device functions for much power saving intentionally.