nages 
  
mages 
thod (1) 
  
(a) A mosaicked image of 8 rectified images 
  
(b) A mosaicked image of 11 rectified images 
  
(c) A mosaicked image of 12 rectified images 
Figure 8. Examples of the proposed method (2) 
(2) A system to create a rectified image of an inclined plane for 
geological survey at a construction site 
This system adopts a plane object image acquisition way, 
because a geometrically corrected image of a slope will be 
utilized for visual interpretation and geological survey at a 
construction site allows rather lower spatial accuracy of a 
rectified image. Figure 8 shows three examples of products 
of the system. The objects are excavation slopes at dam 
construction sites in Japan. Figure 8 (a), (b) and (c) show 
horizontally mosaicked images of the target slopes made of 
a series of 8, 11, and 12 rectified images respectively. 
5. CONCLUSION 
We have developed a method to create a geometrically correct- 
ed image of a digital camera. The major advantage of our 
method is that it is easy for a nonprofessional to create a 
mosaicked image of ortho-images or rectified images of suffi- 
cient quality in a short time without ground survey of control 
points. The method requests no photogrammetry or image 
processing know-how of a user. And necessary hardware of the 
method is compact and not expensive, and no special equipment 
is required. Minimum hardware components of the method are 
a pair of scales such as staffs in leveling, a digital camera that is 
not designed for photogrammetry, and a PC for multi-purpose. 
Since all hardware components are for all purposes and 
available on the market, the cost of the system becomes low. 
Two systems adopting our method have been developed. One 
is an image-based information management system for resto- 
ration of cultural heritages, and the other is a system to create a 
rectified image of an inclined plane for geological survey at a 
construction site. Both systems are currently practicable. The 
former operates mainly for mural paintings to make restoration 
plans, and the latter operates mainly for geological visual 
interpretation at dam construction sites. 
REFERENCES 
Hongo, K., Matsuoka, R., Fujiwara, S., Masuda, K., Aoki, S., 
2000. Development of Image-Based Information System for 
Restoration of Cultural Heritage. International Archives of 
Photogrammetry and Remote Sensing, Amsterdam, the 
Netherlands, Vol. XXXIII, Part B5/1, pp. 372-379 
Matsuoka, R., Shirai, N., 2000. Development of Software to 
Create a Rectified Image of an Inclined Plane. Proceedings of 
the 21st Asian Conference on Remote Sensing, Taipei, Taiwan, 
Vol. 1, pp. 119-124 
ACKNOWLEDGEMENTS 
The authors are grateful to Mr. Katsuhiko Masuda and Mr. 
Shigeo Aoki, researchers of Tokyo National Research Institute 
for Cultural Properties, for their advice on the image-based 
information management system for restoration of cultural 
heritages. We also express our appreciation to Mr. Masayoshi 
Kuji, a geological engineer of Technology Research Institute of 
Maeda Corporation, for his help at the development of the 
system to create a rectified image of an inclined plane. 
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