Orthorectification of a satellite EROSA1 Milan image by GPS RTK control and check points: different models comparison

The subject of this paper concerns the study of a high resolution EROS A1 satellite image of the city of Milan, the area is highly urbanised and without significant height differences. The image has been orthorectified using different algorithms, both physically based and black models, and different software packages, both commercial and scientific. The Ground Control Points (GCP) and Check Points (CP) have been surveyed using a GPS-RTK method that is cheaper and faster than a post-processing technique, particularly useful if updated cartography is not available. The Orthorectification has been performed with different GCP configurations. The second part of this paper deals with a 3D City Model extraction from the 3D digitai City Base Map. The image has been orthorectified taking into account the shape of the buildings, in particular in the area around the Pirelli skyscraper