Visual perception model of road users in nocturnal fog using videophotometric image analysis
Résumé
Fog is one of the most dangerous meteorological phenomena in terms of road visibility perturbation. The decrease and the levelling of luminance levels reduce the contrasts and delay the detection of obstacles. Experimentations with observers were carried out in a fog chamber in order to quantify the visual degradations generated by the fog in nocturnal conditions. The luminance of the scene has been recorded with videophotometers based on calibrated CCD cameras. These photometric measurements led to the calculation of visibility thresholds that are compared to theoretical values provided by Adrian's model. The visibility levels are then determined. Further investigations with other observers are needed in order to reduce the statistic variance of the results, and then enable to propose an adaptation of the model in fog.