Haze Removal Algorithm Using Improved Restoration Model Based on Dark Channel Prior

Abstract

In recent years, with the rapid development of social economy and the people’s living standard, the awareness of security precaution is becoming increasingly important. However, in severe weather conditions, rain and haze have a large influence on the images obtained by video monitoring like the image contrast information, and it has a bad impact on the security work. So the clarity of images becomes very meaningful, and researchers start to pay attention to the field of image dehazing. Among many studies, the dark channel prior dehazing algorithm is a major breakthrough in the field of image dehazing technology. The advantages of this algorithm mainly focus on solving the problem of over-dependence on the physical model of sky scattering, poor adaptability to images containing sky regions and the problem that the processed images are too dark. Based on the atmospheric physical model, this research proposed a haze removal algorithm based on dark channel prior, which has good robustness to the bright sky regions, and also has a good effect on the edges. Firstly, the haze images were detected to see whether sky regions are included or not. Secondly, haze images that have sky regions were segmented into sky region and non-sky region. Then, the haze images that have sky regions and that have no sky regions were dehazed respectively. Finally, the quantitative assessment is based on NIQE (Natural Image Quality Evaluator), and the qualitative assessment is based on human subjective visual standards to compare the intrinsic images results. Quantitative and qualitative results both demonstrate that the performance of the proposed method is better than other techniques in the field of image dehazing that using dark channel prior. The proposed method can be better applied in the area of video image processing.