Derivation and Validation of High-Resolution Digital Terrain Models from Mars Express HRSC Data

Derivation and Validation of High-Resolution Digital Terrain Models from Mars Express HRSC Data

Published in:
Photogrammetric Engineering & Remote Sensing Vol. 75 No. 9, Sep 2009, pp. 1127-1142

Authors:
Klaus Gwinner, Frank Scholten, Michael Spiegel, Ralph Schmidt, Bernd Giese, J├╝rgen Oberst, Christian Heipke, Ralf Jaumann, and Gerhard Neukum

Abstract:
The High Resolution Stereo Camera (HRSC) onboard the Mars Express mission is the first photogrammetric stereo sensor system employed for planetary remote sensing. The derivation of high-quality digital terrain models is subject to a variety of parameters, some of which show a significant variability between and also within individual datasets. Therefore, adaptive processing techniques and the use of efficient quality parameters for controlling automated process- ing are considered to be key requirements for DTM generation. We present the general procedure for the derivation of HRSC high-resolution DTM, representing the core element of the systematic derivation of high-level data products by the Mars Express HRSC experiment team. We also analyze test series applying specific processing variations, including a new method for signal adaptive image preprocessing. The results are assessed based on internal quality measures and com- pared to external terrain data. Sub-pixel scale 3D point accuracy of better than 10 m and a DTM spatial resolution of up to 50 m can be achieved for large parts of the surface of Mars within a reasonable effort. This confirms the potentials of the applied along-track multiple stereo imaging principle and allows for a considerable improvement in our knowledge of the topography of Mars.