Energy-efficient color approximation for digital LCD interfaces

The limited resolution capabilities of color displays, coupled with the limited perceptual resolution of the human eye has been exploited to reduce the actual number of colors that are simultaneously displayed. In this work, we propose a color approximation approach, orthogonal to traditional color simplification schemes done either in the frame buffer or in the LCD controller, that targets the reduction of the energy required for the transmission of color data on digital LCD interfaces. Our approach leverages the serial nature of the transmission so as to approximate RGB pixel values with suitable codes that minimize the number of transitions on the LCD bus, for a given tolerated image quality level. Application of this scheme on a set of images shows energy savings from 60% to 75%, depending on the image quality.