shown in figure 11. It is clear that the quality of the detailed 
scanned sections (1 and 2, figure 11) is much higher than the 
image-based regions (3 and 4), which lack the small geometric 
details. It is particularly more convincing when viewing these 
sections up close while navigating through the model. 
Scanned Regions 
Figure 6: Textured model of the front building showing the 
regions that were scanned. 
Figure 7: The main architecture elements of the entrance of the 
Abbey created by image-based modeling. 
X ' 
Figure 8: Added trim points 
and re-meshing basic model. 
Figure 9: Model of scanned 
left-side wheel and peacock. 
Figure 10: Close up on the wire-frame model of part of the 
middle of the wheel. 
Figure 11: Close up on the textured model. Sections 1 and 2 are 
scanned details, 3 and 4 are image based. 
6. CONCLUDING REMARKS 
A multi-technique approach to creating detailed 3D models of 
cultural heritage sites, classical architectures, and monuments 
was presented. It combines image-based and range-based 
modeling as well as image-based rendering. The image-based 
modeling is a semi-automatic approach that is designed 
specifically to take advantage of properties and arrangements 
common to such objects. A representative example, the Abbey 
of Pomposa near Ferrara, Italy, was demonstrated. In this 
example, the main structural elements were reconstructed from 
a small number of images while a laser scanner acquired the 
irregular shapes and fine details. In the image-based approach, 
parts of the process that can straightforwardly be performed by 
humans, such as registration, extracting seed points, and 
topological segmentation, remain interactive. Numerous details 
plus the occluded and the un-textured parts are added 
automatically by taking advantage of some of the object 
characteristics and making some realistic assumptions about the 
elements shapes and the relations between them. Modeling of 
the scanned sections was carried out fully automatically while 
its registration with the full image-based model was interactive. 
Current and near future activities focus on increasing the level 
of automation and ease of use of the approach, and applying it 
to a wide range of projects all over the world. 
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