better quality camera and smaller size object with high contrast 
feature definition. 
A compo section in Venice, with the San Giacomo dell'Orio 
church, is shown in figure 10-C. It illustrates cylindrical shaped 
structures and great deal of occlusions. Figure 10-D shows a 
large historic building, la Caserne Dalhausie, in Quebec City. 
Ten images were taken to cover three sides of the building (the 
back side was attached to other buildings). The model, which 
has over 3000 points of which only 150 were measured 
interactively, captured all the details of the building including 
the tower. The model in figure 10-E depicts details, including 
irregular elements, of the entrance to Saint Cristina Crypt in 
Apulia, Italy. A historic building on the Rideau Canal in 
Ottawa, figure 10-F, is completely modeled from 9 images. 
7. CONCLUDING REMARKS 
A semi-automatic approach for constructing medium and large- 
scale man-made objects, such as classical architecture, was 
presented. Several representative examples from a small 
number of images taken by tourists were given. 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 the object characteristics and making some 
realistic assumptions about the elements shapes and the 
relations between them. Efforts to automate the whole 
procedure are continuing. When conditions allow, the steps of 
initial point extraction and image registration can be fully 
automated, although this still requires numerous closely-spaced 
images. In the mean time, to achieve immediate and useful 
results, parts of the process necessitate human interaction. 
Acknowledgements 
My colleagues Francois Blais and Angelo Beraldin took many 
of the images. Emily Whiting constructed some models. 
References 
Beraldin, J.-A., F. Blais, L. Cornouyer., M. Rioux, S.F. El- 
Hakim, R. Rodella, F. Bernier, N. Harrison, 1999. 3D imaging 
system for rapid response on remote sites. IEEE proc. of 2". 
Int. Conf. 3D Digital Imaging and Modeling, pp. 34-43. 
Bougnoux, S., 1998. From projective to Euclidean space under 
any practical situation, a criticism of self-calibration. Proc. Intl. 
Conf. Computer Vision (ICCV98), pp. 790-796. 
Debevec, P., C.J. Taylor, J. Malik, 1996. Modeling and 
rendering architecture from photographs: A hybrid geometry 
and image-based approach. SIGGRAPH 96, pp. 11-20. 
Liebowitz, D., A. Criminisi, A. Zisserman, A., 1999. Creating 
Architectural Models from Images. EUROGRAPHICS, 18(3). 
Dick, A.R., P.H.Torr, S.J. Ruffle, R.Cipolla, 2001. Combining 
single view recognition and multiple view stereo for 
architectural scenes. Proc. 8th IEEE International Conference 
on Computer Vision (ICCV'01), pp. 268-274, July. 
El-Hakim, S. 2002. http://www.vit.iit.nrc.ca/elhakim/home.html 
Faugeras, O., L. Robert, S. Laveau, G. Csurka, C. Zeller, C. 
Gauclin, I. Zoghlami, 1998. 3-D reconstruction of urban scenes 
from image sequences. Computer Vision 
Understanding, 69(3), pp 292-309. 
and Image 
Fitzgibbon, A.W., Zisserman, A., 1998. Automatic camera 
recovery for closed or open image sequences. European Conf. 
On Computer Vision (ECCV'98), vol. 1, pp. 311-326. 
Fraser, C.S., 1994. Network design considerations for non- 
topographic photogrammetry. Photogrammetric Engineering & 
Remote Sensing, 50(8), pp. 1115-1126. 
Harris C., M. Stephens, 1998. A combined corner and edge 
detector. Proc. 4th Alvey Vision Conf., pp. 147-151. 
Hartley, R., 2000. Ambiguous configurations for 3-view 
projective reconstruction. In European Conf. Computer Vision, 
pp. 922-935, Dublin, Ireland, Springer-Verlag. 
Kahl, F., Triggs, B., Astrom, K., 2000. Critical motions for 
auto-calibration when some intrinsic parameters can vary. 
Journal of Mathematical Imaging and Vision 13, pp. 131-146. 
Kahl, F., Hartley, H., Astrom, K., 2001. Critical configurations 
for N-views projective reconstruction. IEEE Computer Vision 
and Pattern Recognition (CVPR’01), vol. 2, pp. 158-163. 
Lee, J, R. Haralick, L. Shapiro, 1987. Morphologic edge 
detection. /EEE J. Robotics and Automation, 3(2), pp 142-156. 
Oliensis, J., 2000. A critique of structure-from-motion 
algorithms. Computer Vision and Image Understanding, 80(2), 
pp 172-214. 
Pollefeys, M., R. Koch, L. Van Gool, 1999, Self-calibration and 
metric reconstruction in spite of varying and unknown intrinsic 
camera parameters. International J. of Computer Vision, 32(1), 
pp. 7-25. 
Shum, H.Y., R. Szeliski, S. Baker, M. Han, P. Anandan, , 1998. 
Interactive 3D modeling from multiple images using scene 
regularities. Eur. Workshop 3D Structure from Multiple Images 
of Large-scale Environments — SMILE, pp 236-252. 
Sturm, P. 1997. Critical Motion Sequences for Monocular 
Self-Calibration and Uncalibrated Euclidean Reconstruction. 
Proc. Int. Conf. Computer Vision and Pattern Recognition, San 
Juan, Puerto Rico, pp. 1100-1105. 
Tao, H., Sawhney, H.S., Kumar, R., 2001. A global matching 
framework for stereo computation. Proc. IEEE 8" Int. Conf. On 
Computer Vision, ICCV'2001, Vol. 1, pp. 532-539. 
Triggs, W., P. McLauchlan, R. Hartley, A. Fitzgibbon, 2000. 
Bundle Adjustment for Structure from Motion. in Vision 
Algorithms: Theory and Practice, Springer-Verlag. 
Tzonis, A., Lefaivre, L., 1986. Classical Architecture — The 
Poetics of Order. MIT Press, Cambridge, MA. 
van den Heuvel, F.A., 1998. 3D reconstruction from a single 
image using geometric constraints.  ZSPRS Journal 
Photogrammetry & Remote Sensing, 53(6), pp. 354-368. 
Werner, T., Zisserman, A., 2002. New technique for automated 
architectural reconstruction from photographs. Proc. 7^ 
European Conf. Computer Vision, Copenhagen, May. 
Zwillinger, D. (ed.), 1996. Standard Mathematical Tables. 30^ 
Edition, CRC Press, Inc., Florida, pp 311-316. 
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