Automated Extraction of Road Markings from Mobile Lidar Point Clouds

Among implicit information of laser points, the strength of reflection of laser points is closely related to the property of road materials which helps detecting road markings. This paper presents a novel approach to automatically extracting road markings from mobile lidar point clouds. An interpolation method is first used to generate a georeferenced feature image of the point cloud, which helps to isolate the points of road surfaces. Then, an algorithm is used to separate these points within a range according to their strength of reflection. The separated points are further segmented to remove non-road points based on height threshold. Finally, the outlines of road markings are extracted from the segmented points using the semantic knowledge of road markings. The results demonstrated that our method was very promising for automatic extraction of road markings from lidar point clouds collected by a land-based mobile lidar system, an Optech Lynx Mobile Mapper.