>. Istanbul 2004 
out 100 meters 
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c 
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B5. Istanbul 2004 
6. CONCLUDING REMARKS 
Although the castle-modeling project is still a work in progress, 
we have reached solid conclusions about the effectiveness of 
image-based techniques for this purpose. Using images taken 
from a low-flying helicopter and from ground levels, combined 
with existing floor plans and limited surveying, we can 
completely model a complex castle such as the Stenico castle 
with realistic details. Semi-automated modeling and model 
assembly techniques were developed. On average, less than 
2096 of all 3-D points were created interactively while at least 
80% were created automatically. The cost and time required 
was much less than reported similar work. In the future, we will 
use an accurate laser scanner on some parts of the castle to add 
higher levels of detail to the model. This will require further 
advances to cope with the increase in model size. 
Acknowledgements 
We express our thanks to Dr. Franco Marzatico, the director of 
Castelli Trentini, and the Autonomous Province of Trento for 
allowing us access to the Stenico castle. 
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