Surface Matching and Difference Detection Without the Aid of Control Points

Monitoring the morphological evolution of the Sciara del Fuoco during the 2002–2003 Stromboli eruption using multi-temporal photogrammetry

“…Due to the impossibility of setting up a control network during the emergency period, the reference system was fixed by a set of well-defined objects identified a posteriori in all the images used for the extraction of the 3D models. Should ground control points or well-identifiable image points not be available, the co-registration of two different DEMs can be improved by applying a bleast squares surface matching procedure.Q The basic principles of this approach are described by Karras and Petsa (1993), Pilgrim (1996), and Mitchell and Chadwick (1999). The best-fit procedure is designed to minimize the data representing the surface separation of DEM pairs, which are assumed to be noisy and distributed around null mean value, by estimating similarity transformation parameters.…”

The morphological evolution of the Sciara del Fuoco since 1868: reconstructing the effusive activity at Stromboli volcano

“…In order to preserve the main relief forms, we digitised the contour lines at intervals of the same order of the expected vertical accuracy of the maps that is 10 and 5 m for 1968 and 1937, respectively. The vector data were co-registered with the photogrammetric data by using matching procedures (Pilgrim 1996;Gruen and Akca 2005). The extracted contour lines were checked via a comparative analysis with those measured using the 2001 photogrammetric data (Fig.…”

Remote sensing of permafrost and frozen ground

“…The accuracy of the calculated vertical changes is a function of the accuracy of the repeat DEMs that are used (Etzelmüller, 2000;Kääb, 2005). Pre-and post-processing procedures such as multi-temporal adjustment of photogrammetric blocks, or DEM co-registration, help to improve this accuracy (Pilgrim, 1996;Kääb and Vollmer, 2000;Li et al, 2001;Kääb, 2005;Nuth and Kääb, 2011).…”