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Florin Savopol
The Figure 5: shows the proposed system configuration for near real-time image data downloading in a case of
emergency mapping. This configuration was successfully tested in a simulated situation. All the hardware components
were installed on the top of a 17 floor building situated in the test area used for the flight test on the campus of Laval
University in Quebec City. In order to simulate real flight conditions, the power supply was provided by the same
batteries as used during the test flight.
5 CONCLUSIONS
The possibility of using a multiple-camera system for emergency mapping in near real-time conditions has been
successfully tested.
There are two main solutions for image orientation and exploitation in the case of such a multiple cameras system
mounted on a rigid, stable mount:
A. In a first step, the creation of a synthesized image equivalent to a single high resolution image which would cover the
same area as the total of all the individual single images captured at the same moment. This approach was presented in
(Savopol et al., 1996). In a second step, the synthesised images could be used in a traditional manner for stereo
compilation using standard soft-copy photogrammetric software.
B. To handle all of the individual images of a block in the same manner, using a modified bundle adjustment where
additional condition equations were added in order to take advantage of the known relative orientation parameters
between the camera mounted on their rigid mount.
The evaluation of the image geometry and the precision of the extracted topographic information are still in progress.
Details of the results are expected in the near future.
ACKNOWLEDGEMENTS
The authors wish to thank Mr. Clement Nolette and Mr. Sylvain Lacompte from Laval University for their invaluable
assistance in solving the multiple hardware and software problems during the system integration work.
The authors wish also to thank Hauts Monts Inc., Quebec City for their collaboration by providing the test flight.
REFERENCES
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King, D. (1995): Airborne Multispectral Digital Camera and Video Sensors: a Critical Review of System Designs and
Applications. Canadian Journal of Remote Sensing, Volume 21, No. 3, August 1995.
Savopol, F., Boulianne, M. and Nolette, C.(1996): Production d’images synthétiques de haute résolution pour la
stéréorestitution photogrammétrique. The International Archives of Photogrammetry and Remote Sensing, Volume
XXXI, Part B2. Vienna 1996
Schiewe, J. (1998): Effect of lossy data compression techniques on geometry and information content of satellite
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