In: Paparoditis N., Pierrot-Deseilligny M.. Mallel C.. Tournaire O. (Eds), IAPRS. Vol. XXXVIII. Part ЗА - Saint-Mandé, France, September 1-3, 2010
Position of S (Z)
1 ; .
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■ :. !
к
[ ♦ 0,3 pixel of noise *0,5 pixel of noise 1,0 pixel of noise
Figure 9: Projection center of images in Z after calibration and
noise on measures
Positions of S (X,Y)
-0,25 -0,2 -0,15 -0,1 -0,05 0 0,05 0,1 0,15 0,2 0,25
A
1
1
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♦ 1
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♦ 0,3 pixel of noise ■ 0,5 pixel of noise 1,0 pixel of noise
Figure 10: Centres of projection of images in plan (X.Y) after
calibration and noise on measures
Position of S (Z)
♦ 0,3 pixel of noise ■ 0,5 pixel of noise 1,0 pixel of noise
Figure 11: Centres of projection of images in Z after calibration
and noise on measures
3.3 Conclusion
In this section, we exhibited the limits of the polygon based cal
ibration and the difficulty to estimate the intrinsic and extrinsic
parameters in the same process. The geometry of the panoramic
avoids calculating the position of each image. Furthermore, ge
ometry of panorama constraint naturally and geometrically intrin
sic parameters.
4 EXPERIMENTS WITH REAL DATA
2 models can be more than 10 pixels (in the corners). It means
an difference on field of camera of 0.7123° in column and per
0.5989° in line.
Figure 12: Sample of panorama
5 CONCLUSIONS AND FUTURE WORK
This paper has presented a method to calibrate a camera's intrin
sic parameters but also to estimate a distortion pattern. We have
shown that this method is not sensitive to noise and it is applica
ble with both short and long focal. Future work will consist on
looking for more complex and accurate model. We also look for
a framework to estimate the mechanical residual parallax.
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After working with simulated data, we have calibrated a real cam
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of the process on real data. We also compare our results with a
calibration on a topometrically surveyed network targets.
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