Validation of an automatic image orthorectification processing

Following SPOT5 launch, Spotlmage and French National Geographic Institute (IGN) have decided to design a worldwide accurate database called Reference3D^TM using data from the High Resolution Stereoscopic SPOT5 instrument (HRS). Spotlmage and IGN have also decided to develop and commercialize a system called ANDORRE to produce orthorectifled images thanks to Reference3D^TM data. ANDORRE has been designed to take advantage of Reference3D^TM planimetric and altimetric accuracy to automatically register and rectify any image from SPOT satellites. In this framework, CNES is acting as prime contractor to realize and industrialize the algorithms following a preliminary study undertaken by IGN. This paper focuses on the validation of the geometric performances of the algorithms. A special attention is also paid to the processing time in order to achieve the rectification of a 24000×24000 image in less than one hour.