A luminance rendition method based on local visual adaption

Images captured under non-uniform lighting environment often suffer saturation and underexposure. We present a luminance rendition method based on visual adaption to make illumination compensation. A new pixel-by-pixel key value is constructed to represent the local visual characteristic. Based on the careful consideration of it, we propose a space-varying logarithm mapping function with adaptive parameters to render the luminance firstly. Then the modified linear color restoration and autolevel step serve as the post processing. Experimental results prove the proposed method is useful to enhance the unfavorably illuminated images.