Power-constrained backlight scaling and contrast enhancement for TFT-LCD displays

We propose a novel backlight-scaled contrast enhancement algorithm to maintain the image quality when the backlight of a TFT-LCD display is dimmed for power reduction. First, we derive the transformation function to maintain the perceived luminance and enhance the contrast. Second, we model the perceptual distortion, which describes the information loss due to the backlight scaling. Then, we propose a Lagrangian method to maximize the backlight-scaled image contrast subject to the constraint on the perceptual distortion. Simulation results show that the proposed algorithm provides better image qualities than the conventional algorithms.