Quantitative response of subjective visual recognition to fog concentration attenuation based on image standard deviation

Abstract

Traffic signs are an essential reminder to drivers and passengers. In the fog environment, the absorption and scattering of water molecules in the propagation medium contribute to the attenuation of beam energy, affect the transmission of visual information, and make people unable to correctly identify traffic information. In this study, we simulated the fog environment in the laboratory, improved the method of defining fog concentration in previous experiments, measured fog concentration with the TSI 8350 EP dust meter, and defined standard deviation based on digital image processing theory to characterize image characteristics. We established a subjective visual evaluation environment in the laboratory, invited participants to participate in subjective evaluation experiments, and obtained the relationship between subjective evaluation and image features in turn. We calculated and obtained the quantitative relationship between subjective evaluation and fog concentration based on the typical time axis of fog concentration and the image's standard deviation. This study's results can enhance people's scientific understanding of the traffic environment, and provide data support for further research.