ciel 
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Evaluation of Digital Elevation Modelling and Ortho-image Production from 
Airborne Digital Frame Camera Imagery 
Alexander Chichagov” 
Douglas King" 
Department of Geography 
Carleton University 
1125 Colonel By Drive 
Ottawa, Ontario 
K1S 5B6 
Tel.: (613) 588-2600 (8439); Fax: (613) 788-4301 
ABSTRACT 
The objective of this research is to evaluate airborne digital frame camera imaging in digital 
elevation modelling and ortho-image production for areas of natural and rugged terrain at scales 
similar to standard mapping scales. A Kodak Megaplus 1.4 digital frame camera with 1280 x 1024 
pixel format was flown over the Gatineau Park in May, 1993. The altitude selected was 
approximately 3,940 m above ground level to provide similar ground coverage to standard 
1:10,000, 23 cm photography. The corresponding ground pixel size was about 2.0 m. For an 
initial stereo triplet, over fifty points were selected in the imagery, four for control and the rest as 
check points. These were accurately surveyed using rapid-static differential GPS techniques. À 
digital elevation model (DEM) for the triplet was created from the control points using commercial 
software which includes automated image matching and elevation determination through calculation 
of parallax at each point. Residuals for each check point in relation to the elevation model and an 
overall RMS error were computed. An ortho-image for the area was then produced from the DEM. 
Methodology and results of airborne imagery acquisition, DEM and ortho-image production, and 
DEM accuracy evaluation will be presented. 
Notes: Poster presentation preferred in GIS symposium, although both an oral presentation and 
ISPRS presentation would be acceptable if you need a paper to fill in a time slot for a 
specific theme. An abstract will be submitted in French with the final version of the 
paper. 
  
: M.A. Candidate 
* : 
Assistant Professor 
297