An improved low illumination image enhancement algorithm with color preserving

To solve the problem of color distortion existing in low illumination image enhancement method, a novel low illumination image enhancement method based on dark-channel prior with the capability of preserving scene color is presented. First, the intensity of every image pixel with dark-channel prior is estimated directly, and for dealing with wrong dark-channel values in white region, the regions with wrong grey values by calculating the minimum difference value of the RGB channels and correct the dark-channel values of the regions are founded. Then, a linear smoothing method is used to refine the block effect caused by dark-channel prior, and the enhanced image is achieved by scaling up the pixel intensity according to its value in dark-channel image. Finally, by comparing with the existing low illumination image enhancement method, the effectiveness of our method with better color preserving capability and higher PSNR is proved.