Too many pixels to perceive: Subpixel shutoff for display energy reduction on OLED smartphones

Organic light-emitting diode (OLED) has been widely recognized as the next-generation mobile display. Recently smartphone manu facturers have been pushing up the pixel density of OLED display Unfortunately such an effort does not necessarily improve the everyday viewing because of the limitation in human visual acuity Instead, high pixel density OLED can drain the battery power even more quickly since the power dissipation of OLED is determined by the number of displayed pixels and their RGB values, or sub pixels. This paper presents a new design dimension to remedy this prevailing issue by leveraging the intuition that shutting off redun dant subpixels of the display content on OLED can reduce power consumption without impacting viewing perception. We introduce ShutPix, a power-saving display system for OLED smartphones that can optimally shut off the redundant subpixels before the con tent is displayed. Inspired by the motivational studies, ShutPix is empowered by a suite of designs based on visual acuity, human perception, and content redundancy. Experimental results show that ShutPix can, on average, reduce 21% of display power and 15% of system power without degrading user viewing experience.