Title :
Image Enhancement for Backlight-Scaled TFT-LCD Displays
Author :
Tsai, Pei-Shan ; Liang, Chia-Kai ; Huang, Tai-Hsiang ; Chen, Homer H.
Author_Institution :
Grad. Inst. of Commun. Eng., Nat. Taiwan Univ., Taipei
fDate :
4/1/2009 12:00:00 AM
Abstract :
One common way to extend the battery life of a portable device is to reduce the LCD backlight intensity. In contrast to previous approaches that minimize the power consumption by adjusting the backlight intensity frame by frame to reach a specified image quality, the proposed method optimizes the image quality for a given backlight intensity. Image is enhanced by performing brightness compensation and local contrast enhancement. For brightness compensation, global image statistics and backlight level are considered to maintain the overall brightness of the image. For contrast enhancement, the local contrast property of human visual system (HVS) is exploited to enhance the local image details. In addition, a brightness prediction scheme is proposed to speed up the algorithm for display of video sequences. Experimental results are presented to show the performance of the algorithm.
Keywords :
image enhancement; image sequences; liquid crystal displays; thin film transistors; video signal processing; LCD backlight intensity; backlight-scaled TFT-LCD displays; brightness compensation; contrast enhancement; global image statistics; human visual system; image enhancement; image quality; portable device; video sequences; Contrast; LCD backlight; image enhancement; power management;
Journal_Title :
Circuits and Systems for Video Technology, IEEE Transactions on
DOI :
10.1109/TCSVT.2009.2014022