Method and device for detecting fog at night

摘要

A method of detecting the presence of an element (fog, rain, etc. . . . ) disturbing the visibility of a scene illuminated by a headlight (105, 107) at night. The method comprises:
a) acquiring an image of the scene with the help of a camera (120);b1) detecting the light sources in the image;b2) detecting the presence of the disturbing element as a function of the halo (H) appearing in the image in the vicinity of the light sources;c) detecting the presence of the disturbing element in the image as a function of the backscattering of the light emitted by the light sources; andd) weighting the results of the detections performed in steps b2) and c) in such a manner as to output an indication concerning the presence of the element disturbing the visibility of the scene.;The method provides satisfactory results in an environment with or without lighting. The invention also provides a computer program and a device for implementing the method.

主权项

1. A method of detecting the presence of an element disturbing the visibility of a scene illuminated by at least one light source at night; said element belonging to the group comprising fog, smoke, rain, and snow; the method comprising a step a) in which at least one image of the scene is acquired with the help of a camera, said at least one light source being stationary or swivel-mounted relative to the camera; the method further comprising the following steps:
b1) detecting at least one light source forming part of the scene in said at least one image; b2) detecting the presence of a disturbing element as a function of the halo appearing in said at least one image in the vicinity of said light source(s); c) detecting the presence of a disturbing element in said at least one image or in a portion thereof as a function of the backscattering of light emitted by said stationary or swivel-mounted light source(s); and d) weighting the results of the detections performed in steps b2) and c), in such a manner as to output an indication concerning the presence of an element disturbing the visibility of the scene.