ISPRS Commission III, Vol.34, Part 3A ,,Photogrammetric Computer Vision‘, Graz, 2002
Figure 7-a. Border Points (Building 1)
Figure 7-b. Border Points (Building 2)
In order to convert the extracted roof border points
into polygons we used the algorithm presented in Bimal and
Kumar 1991 and Bimal and Kumar (1992). The basic idea is
to go through all the border points and only retain those that
that are significant, i.e. those that represent vertices. The
elevations of the corner points are then computed from the
refined DEM. Adjacent corner points are grouped to form
the building wire-frames. Figure 8 shows the two resulting
building wire-frames.
A - 106
Figure 8. Building Wire-Frames
ACKNOWLEDGMENT
The authors would like to thank the Army Research Office
for sponsoring this work. We also would like to thank
Professor Edward Mikhail for his help and advice.
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