The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Voi. XXXVII. Part B4. Beijing 2008 
processing, make our method interesting in many applications. 
In any case, being the product an open source, the interested 
users can also improve its functionalities by changing parts of 
the code or implementing new modules. 
AKNOWLEDGEMENTS 
The research was partially supported by the Italian Ministry for 
School, University and Scientific Reasearch (MIUR) in the 
frame of the project MIUR COFIN 2005 “Analisi, 
comparazione ed integrazione di immagini digitali acquisite da 
piattaforma aerea e satellitare” - National Principal Investigator: 
S. Dequal. 
We thank Sardinia Region for providing the LiDAR dataset, the 
DTM/DSM and the orthophotos. 
Moreover we thank all people who have worked at the method 
and software development, specifically Dott. Roberto Antolin, 
who ported the modules from GRASS 5 to GRASS 6. 
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