Estimation de la visibilité météorologique par caméras routières
نویسنده
چکیده
The measurement of the meteorological visibility is an important element forthe safety of road and air transport. We propose in this thesis a meteorological visibilityindicator adapted to video surveillance cameras of the road network. This descriptor isbased on the module of the gradient selected in areas that follow Lambert’s reflectionlaw. The response of this descriptor is derived from a model based on the statistical dis-tribution of depth in the scene. Calibration is performed with data from a visibilimeter,or with a depth map from a digital terrain model. The results are then compared withreference data obtained from a visibilimeter and show a similar mean error for imagestaken in different illumination and meteorological visibility conditions.
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