Fusion of HyMap hyperspectral with HRSC-A multispectral and DEM data for geoscientific and environmental applications

The combination of the High Resolution Stereo Camera-Airborne (HRSC-A) and the HyMap hyperspectral scanner covers essential needs for the classification and mapping of land cover types and other environmental monitoring and planning purposes: very high spatial and spectral resolution data as well as a Digital Elevation Model (DEM). The HRSC-A provides geocoded multispectral and DEM data. The resolution is 10 cm from a flight altitude of 2500 m. The HyMap covers the spectral range from 440-2540 nm in 128 channels with a pixelsize of 5 m from 2500 m altitude. The HyMap data can also be parametrically georeferenced. The complementary information gained by the individual sensors mutually enhances data quality and the efficiency of classification and feature extraction in many ways. The height information of the DEM can be used for classification and for geometric, atmospheric and photometric (BRDF) correction of the image data of both sensors. Ground control points on HRSC-A othoimage data clearly improve the geocoding of the HyMap sensor. Spectrally homogenous areas and features in the subpixel-scale in the HyMap data can be differentiated using a textural and/or spectral analysis of the co-registered HRSC-A data. Spectral endmembers can be selected in the HyMap data and visually identified in the HRSC-A data. Spectral unmixing of the HyMap data can be evaluated and enhanced by quantitatively analyzing the fractions of the spectral endmembers in the HRSC-A data. The combination of HRSC-A and HyMap data mutually improves the potential of the individual sensors and the classification results; furthermore it meets the demand for geocoded digital data with high geometric accuracy needed for many (GIS) applications.