Assessing the Operationality of Ship Detection from Space

Since the launch of ERS-1 in 1991, a decade and a half of research has been devoted to automatic detection of ships in satellite radar imagery. However, it is only quite recently that this capability is operationally used; at present primarily in the fields of fisheries control and defence. The key has been the combination of remote sensing data with vessel position data from other sources. In contrast to detection, classification of ships in satellite radar imagery is much less developed, and will likely remain difficult in the near future. Concerning optical imagery, the recent high-resolution systems can readily detect ships from space, and their classification power is much higher than that of radar. However, much less effort has been devoted to development of automatic systems for optical, mostly because these sensors suffer more from the weather and are less suited for wide area surveillance. Nevertheless, there has been a recent catching up, and the first operational systems for automatic ship detection and classification in optical satellite images are starting to appear.