At a computing system comprising one or more processors and memory, the computing system receives road data collected on a moving vehicle along a road, the road data comprising a two-dimensional streetscape image, a three-dimensional point cloud, and inertial navigation data, identifies, within the two-dimensional streetscape image, a ground region image corresponding to the road based on a spatial position relation of the two-dimensional streetscape image and the three-dimensional point cloud according to the inertial navigation data, and detects at least one target road traffic marking in the ground region image, determining three-dimensional coordinates of the at least one target road traffic marking based on the spatial position relation of the two-dimensional streetscape image and the three-dimensional point cloud.