Tone mapping is a technique used in image processing and computer graphics to map a set of colors to another set so as to approximate the appearance of high dynamic range images in media with a more limited dynamic range. However, tone mapping may fail to reproduce the full range of light intensities present in natural scenes and may cause problematic contrast reduction from the scene values to the displayable range. Preserving the fine image details and color tones in the original scenes are important in many applications.
Recently, Dynamic Backlight Control (DBC) in mobile Liquid Crystal Display (LCD) device has become one of the image display applications in applying the tone mapping for scaling up the image data while dimming the backlight so as to minimize the backlight power consumption. However, the image data loses its accuracy during the tone mapping especially in high brightness region.
Therefore, the art would benefit greatly from image data processing methods that can avoid the loss of fine image details or contrast in dynamic backlight control applications.