Research On Optimization And Application Technology Of The Android Screen Power Usage Model

With the rapid development of smartphone-related hardware and software tech-nologies,the functions of smartphone applications are becoming richer and richer in recent years,and their power usage is also growing accordingly.However,the limited battery capacity has become one of major concerns of smartphone manufacturers and users.Although there is a large amount of research work on measuring the power us-age of the smartphone operating system or its applications,they are mainly based on the hardware power usage models constructed by the smartphone operating system itself.Then,the accuracy of such hardware power usage models is particularly important for the accuracy of these pieces of work.As one of the world's most popular smartphone operating systems,Android mea-sures the power usage of each hardware component,including the screen,since the last time a smartphone was fully charged.Related research shows that the screen has become one of the main sources of the power usage of a smartphone.However,the An-droid's built-in screen power usage model has some defects.In this model,the power usage of the screen is only related to its brightness,but in fact it is also related to the contents displayed for new OLED screens.Hence,the accuracy of the Android screen power usage model needs reconsideration.In this thesis,we present an optimized screen power usage model.Based on this model,we propose two techniques to reduce the power usage of the screen on an An-droid smartphone.Specifically,our work can be summarized as follows:1.We recognize the regression relationship between the power usage of the screen and its displayed contents,and present an optimized screen power usage model-the OLED screen power usage model,which considers not only the screen's brightness,but also its displayed contents.2.We present the implementation of the OLED screen power usage model in the An-droid system framework.Then we design and conduct experiments to verify the accuracy of our model from various aspects,meanwhile evaluating its computation overhead.3.We propose two techniques to reduce the power usage of the screen,namely,invert-ing colors of screen contents and adjusting screen color schemes.We also present the implementation of these two techniques in the Android system framework,and conduct experiments to evaluate their actual effects.