Automatic extraction of main roads using aerial images

In this paper we describe a method for automatic extraction of main roads in high resolution aerial images. Because a road may vary in color we aim at the detection of its centerline that is more uniform in color and shape. For this purpose, the centerline is modeled as being a chain of short line segments. The method is based on an iterative process and is composed by two stages: in the first stage seed segments are detected using the Radon transform. The second step is the automatic extraction of the roads centerlines starting from the seeds that were found in the first stage. The Radon transform is again applied to find the chain/series of segments candidates to centerline of main roads. In the final part of the paper we present experiments using this approach and the results compared with a reference image. The accuracy of the automated method is evaluated considering the completeness, correctness, and RMS indexes.