xels are
> + F'N)
FN)
Yypothe-
ormance
'al struc-
nents of
‚ely high
ny build-
ver right
red prim-
d peaked
building
intensity
cet.
hypothe-
the per-
; at least
the high
flect this
rh quality
amounts
e entirely
formance
chniques,
Figure 8: PIVOT results on RADT5WOB
this fully automated monocular system is able to achieve ro-
bust performance on images taken from widely differing view-
points, with large variations in image photometry and scene
content.
7 CONCLUSIONS AND FUTURE WORK
Future work on PIVOT is directed along several research av-
enues, many of which have been mentioned in this paper: a
generalized attachment strategy for primitives to handle par-
tial alignments of primitives; extrusion of primitives along all
vanishing lines, not just in the vertical direction; the addition
of trihedral vertices as a supplementary intermediate feature:
the ability to handle severe low-level edge fragmentation; and
capabilities for interfacing with semi-automated systems.
While PIVOT is still under development, current results il-
lustrate the power and potential of the thorough integration
of photogrammetric methods in automated feature extrac-
tion algorithms for aerial image analysis. The combination of
computer vision techniques with a rigorous central projection
camera model leads to superior building extraction perfor-
mance on a wide variety of scenes, a necessity for the use
79
evaluation building branch | miss | quality
detection % | factor | factor %
2D 90.7 0.24 0.10 74.3
3D 84.4 0.30 0.18 67.1
Table 9: Evaluation results for RADT5WOB
of automated systems for the timely construction of highly
detailed spatial databases.
8 ACKNOWLEDGEMENTS
| wish to thank the members of the Digital Mapping Labora-
tory, particularly Steve Cochran, Yuan Hsieh, Chris McGlone,
Dave McKeown, and Michel Roux, for many insightful dis-
cussions on issues in automated building extraction.
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