Detection algorithm of video image distance based on rectangular pattern

As the traditional visibility instrument is expensive, its application field is limited and it is difficult to realize high density coverage on road, realizing the detection and precaution of the foggy weather, especially for the agglomerate fog. This paper puts forward a detection algorithm of video image distance based on rectangular pattern,making it successful to overcome the defects of the traditional methods. The method uses parameters of camera calibration to establish the transformation model of video image distance, which simplifies the original method in the field of calibration. Making it possible to realize high density coverage of camera in the highway, and we use it to make precaution and take safety management of highway in foggy weather condition, especially a sudden agglomerate fog weather condition.