Extraction of thin networks on satellite imagery

The high resolution of SPOT images, particularly in the panchromatic mode, is exploited to extract a part of these thin networks in a reliable and partially automatic fashion. The method relies on the extraction of ridges and valleys followed by a linking step, which yields a reliably localized but still broken network. Average grey levels and orientations of these linear pieces of structures are then used to search the original image again in order to complete them. Results for different areas in the southwest of France are given