3. Istanbul 2004 
al, segmentation, 
   
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rouping 
ngs extracted in 
respectively. 
  
     
A 
tor format. 
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
4. CONCLUSIONS 
In this paper, we introduced a concept of pseudo-grid into raw 
laser scanning data to avoid the loss of information and accuracy 
due to interpolation as well as to define the adjacency of 
neighboring laser point data and to speed up the processing time. 
However, the proposed approach suffered from separating trees 
and buildings. It should be mentioned here that a simple 
measure such as circularity and height difference is not enough 
to differentiate them. In order to overcome the drawbacks, we 
need to incorporate new approach such as data fusion into the 
proposed approach. Nevertheless, we could conclude that the 
proposed approach is promising for building detection and 
extraction in automatic fashion. 
5. ACKNOWLEDGEMENT 
This work was supported by grant No. R05-2003-000-10987-0 
from Korea Science & Engineering Foundation. 
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