Regine Brügelmann
— first set vector
----. second set vector
© vertex
e additional vertex
di distances between first
and second set vectors
Figure 7: Distances between two sets of vectors
5 CONCLUSIONS
It is shown that automatic breakline extraction from airborne laserdata in principle is feasible. The quality of the extracted
breaklines is rather good, but stays slightly behind the photogrammetrically measured breaklines. The latter technique
has the advantage of simultaneously obtaining semantic information about the measured objects. Nevertheless, there are
applications which do not require such explicit semantic information, e.g. data reduction or derivation of morphologic
correct DEM's. Concerning the geometric aspects (apart from the semantic meaning), further investigations must show
whether automatically extracted breaklines are in the same measure suited for various applications as photogrammetrically
measured breaklines.
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