Geological mapping on Mars by segmentation of hyperspectral OMEGA data

The OMEGA instrument onboard of ESA's Mars Express mission is the first hyperspectral sensor that has collected data from Mars. The OMEGA team has shown that Mars has considerable surface compositional variation. Spectral interpretation and mineral mapping, however, is difficult on a pixel-by-pixel basis due to sensor noise, an atmosphere dominated by carbon dioxide and especially an unknown surface cover. An object-based segmentation approach is for datasets that are acquired in areas from which we do not have a-priori knowledge useful to ignore the scene-wide effects of the unknown atmosphere and to enhance the spectral contrast of the planet's surface, without any human bias. Unlike common segmentation procedures where distances in feature space are used for pixel similarity criteria, the OMEGA data is segmented using similarity criteria based on spectral absorption feature parameters such as position, depth and area. This paper shows the first results of an object-based processing of OMEGA data and discusses possibiliteis of future development.