Visibility inversion method for expressway

The invention relates to an expressway visibility inversion method, which comprises the following steps of: firstly, carrying out gray processing on a road image, obtaining a lane line contour by utilizing edge detection, then constructing a corresponding relation between real world coordinates and imaging plane coordinates, and according to lane line standards such as expressway dotted line length, line-to-line distance and the like, calculating the visibility of the expressway; performing inversion to obtain parameters such as the height, the overlook angle and the magnification times of the expressway camera; and finally, calculating the actual length of the lane line in the real world according to the contour of the lane line in the grayscale image, and taking the actual length of the lane line in the real world as a visibility estimation basis. Experimental results prove that the visibility inversion method provided by the invention is relatively accurate due to the fact that noise reduction is carried o