EXTRACTION OF ROAD GEOMETRIC PARAMETERS FROM HIGH RESOLUTION IMAGES VALIDATED BY GEODETIC TECHNIQUES

The knowledge of road geometric data provides the main input for safety evaluation of highways. Moreover, Art.13 of the Italian new Road Code requires an implementation of Road Cadastre, for which the knowdlege of the road network - in terms of georeferenced planimetric and altimetric alignments - is needed. In this paper high resolution images have been analyzed in order to develop automatic techniques for the extraction of road geometric parameters. Different algorithms and remote sensing methodologies have been tested starting from the study of the already proposed techniques in order to choose the most suitable one in the Italian particularly complex landscape. Special attention has been paid to the problem of filtering images, in order to reduce radiometric data complexity and noise. Road sections in the Friuli Venezia Giulia Region have been chosen as a field test to validate the geometrical parameters extracted from the images. Different geodetic techniques, also in real time kinematic mode, have been applied to validate the obtained parameters. Finally the extracted features have been superimposed on digital images to be used for GIS (Geographical Information System) applications.