From Relative to Absolute Heights in SAR-based Single-Image Height Prediction

Single-image height estimation has become a scientifically well-studied field in recent years with a large number of publications. However, the aspect that out of the box only patch-wise relative heights are predicted, is very rarely addressed. For many practical applications, though, it is often indispensable to also establish an absolute height reference. In this paper, such a procedure is described for the case of SAR images natively provided in slant range geometry. A coarse resolution, globally available terrain model is used for the transition to absolute heights. An experiment is conducted to test the procedure and to address the problems encountered. It is shown that the presented method reconstructs the geodetically defined urban topography very well even in an area completely unknown to the model.