International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
  
  
Figure 13 Differential DHM 
CONCLUSIONS 
Very good results were achieved when using break lines 
for filtering the DSM to obtain DHM. Less points were removed 
from initial data in comparison with case in which break lines are 
not used. The example showed in this paper-work is suggestive. 
The programs used (RASCOR and Lisa developed at IPI) are 
very good . The filtering and interpolation works very fast and in a 
simple to use interface , but more important : the program 
RASCOR is using now break lines for filtering , which is a big 
improvement because the results are more close to the real 
situation of terrain. 
Like an advertisement I have to say that I only tested a single data 
set . The results obtained with the programs are very good, but I 
think with other data sets, the results may be little different. It 
depends on configurations of terrain in combinations with manmade 
or natural objects , you can find in field. 
The operator should have a image of the area or other type of data 
, in order to set correctly the parameters for program RASCOR. 
Or else, the results may be wrong just because of not knowing 
some little details which are very important for the filter process. 
BIOGRAPHY 
Jacobsen, K. 2001, PC-Based Digital Photogrammetry, 
UN/COSPAR ESA —Workshop on Data Analysis and Image 
Processing Techniques, Damascus, 2001 ; volume 13 of “Seminars 
of the UN Programme of Space Applications, selected Papers 
from Activities held in 2001” 
Jacobsen, K. 2003, RASCOR - manual, Institute for 
Photogrammetry and Engineering Survey ,University of Hannover, 
Germany 
Jacobsen, K., Lohmann, P., 2003, SEGMENTED FILTERING 
OF LASER SCANNER DSMS , ISPRS WG III/3 workshop ,,3- 
D reconstruction from airborne laserscanning and InSAR data“, 
Dresden 2003 
Passini R., Betzner D., Jacobsen K., 2002, Filtering of Digital 
Elevations Models, ASPRS annual convention, Washington 2002 
K. Kraus and N. Pfeifer 2002, ADVANCED DTM 
GENERATION FROM LIDAR DATA 
Institute of Photogrammetry and Remote Sensing 
Vienna University of Technology 
A-1040 Vienna, Austria 
Commission III, Working group 3 
Ilkka Korpela 3D data capture for DEM/DTM/DSM production - 
an introduction to photogrammetric methods and ranging laser For 
course Y196, November 2000 University Of Helsinki 
E.P. Baltsavias , 1999 , Airborne laser scanning : existing systems 
and firms and other resources . Institute of Geodesy and 
Photogrammetry, ETH-Hoenggeberg, Zurich Switzerland . ISPRS 
Journal of Photogrammetry and Remote sensing 54 pag. 
164-198 
Yukihide Akiyama , 2000, The advantages of high density airborne 
laser measurement , Spatial Information Department , Working 
group V/1 , International Rchives of Photogrammetry and Remote 
Sensing Vol. XXXIII, Part B4, Amsterdam 2000, Aero Asahi 
Corporation Japan 
Krysia Sapeta, LIDAR, Analytical Surveys Inc. (ASI), Colorado 
Springs, Colorado 
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