4. CONCLUSION
All presented methods have a same basics assumption: The
topographic terrain features are in dimension much larger than
objects that are filtered out. The off-terrain points are treated as
a high frequent, but not normally distributed, noise
superimposed on observed signal. So, the presented methods
works fine in regions with a clear difference between useful
signal and "noise" in spatial or frequency domain. Otherwise, in
regions where this difference is not so obvious (i.e. rocky
environment"), the result of classification and filtering is not so
reliable (Kraus and Rieger 1999). Therefore, the other
information about measured region (i.e. intensity of received
measuring signal, orthophotos, topographic maps, etc.) and
objects above them are of most importance. The new
generations of LIDAR filters are oriented to combine
geometrical data with intensity data captured by LIDAR and/or
information from other data sources.
REFERENCES
Baltsavias, E.P., 2000 Airborne laser scanning: existing systems
and firms and other resources, ISPRS Journal of
Photogrammetry & Remote Sensing 54(1999) 164-198
Briese, C, Pfeiffer, N... Reiter, 1.. Rieger, W., 2000.
Interpolation of High Quality Ground Models from Laser
Scanner Data in Forested Areas. International Archives of
Photogrammetry and Remote Sensing, ISPRS Workshop, Vol.
32, Part 3-W14, La Jolla, California, 9. -11. November 1999, S.
31 - 36.
Eckstein, W., Munkelt, O., 1995. Extracting objects from
Digital Terrain Models, Remote sensing and reconstruction for
three-dimensional objects and scenes, ed. T.F. Schenk, Proc.
SPIE 2572, Juli 1995.
Kilian, J., Haala, N., Englich, M., 1996. Capture and
evaluation of airborne laser scanner data. International Archives
of Photogrammetry and Remote Sensing, Vol. XXXI, Part B3,
pages 383-388, Vienna, Austria
Kraus, K., 1997. Eine neue Methode zur Interpolation und
Filterung von Daten mit einer schiefen Fehlerverteilung,
Osterreichische Zeitschrift für Vermessungswesen und
Geoinformationen 1, 25-30
Kraus, K. Mikhail] E.M, 1972 Linear least squares
interpolation. Photogrammetric Engineering 38, 1016-1029
Kraus, K., Pfeiffer, N., 1998 Determination of terrain models in
wooded areas with airborne laser scanner data, ISPRS Journal
of Photogrammetry & Remote Sensing 53 (1998) 193-203
Kraus, K., Pfeiffer, N., 2001. Advanced DTM generation from
LIDAR data, International Archives of Photogrammetry and
Remote Sensing, Volume XXXIV-3/W 4 Annapolis, MD, 2001
Kraus,K., Rieger, W., 1999. Processing of laser scanning data
for wooded areas.
http://www.ifp.uni-stuttgart.de/publications/phowo99/kraus.pdf
(accessed 27. Jan 2003)
Peterson, B., Ni-Meister, W., Blair, I.B., Hofton, M.A., Hyde,
P., Dubayah, R., Modeling LIDAR waveforms using radiative
104
transfer model, International Archives of Photogrammetry and
Remote Sensing, Volume XXXIV-3/W 4 Annapolis, MD, 2001.
Pfeiffer, N., Stadler, P., Briese C., 2001 Derivation of digital
models in SCOP++ environment. In proceedings of OEEPE
Workshop on Airborne Laserscanning and Interferometric SAR
for Detailed Digital Terrain Models, Stockholm, Sweden.
Vosselman, G., 2000. Slope based filtering of laser altimetry
data, International Archives of Photogrammetry and Remote
Sensing, Volume XXXIII, Amsterdam, 2000.
Wever, C., Lindenberger, J., 1999. Experiences of 10 years
laser scanning, http://www.ifp.uni-stuttgart.de/publications/
phowo99/wever.pdf (accessed 21 Jan. 2003)
KEY W
ABSTR
One of t
in devel
an impo
integrati
The tra
requiring
updates
assured |
Cadastre
long per
This trai
database
atomicit
several c
ongoing
This pa
impleme
In sever:
broad r
develop:
these co
systems,
the requ
technica
technolo
engineer
Recent
impact :
science
commun
(DBMS)
the qual
of cadas
Further,
efforts ii
Internati
Geograp