ill 
2 23 24 25 26 27 28 29 30 
TRO-—— VERDE OSCURC 
m). 
very image. The 
erating conditions 
are error of unit 
ments was 1.5-2.7 
stability of video 
is analysed, the 
rding to the pixel 
dy, the median is 
d deviation 28.2 
e is surprisingly 
fact, in theory, it 
es. 
), the relationship 
s strong in both 
and X, is —0.72, 
errestrial system); 
x, co-ordinate is 
image centre, and 
ons of both values 
rs is between the 
of 0.95. However, 
ortion parameters 
tively. Obviously, 
ted, -0.95. The 
and the principal 
neter K; (1.5-2.1 
in y-co-ordinates, 
le x- and y- axes, 
a median value of 
imately the same 
alues, the median 
18, so, the affinity 
dies. 
ters also show 
igh there are not 
entres range from 
1 Z direction (Fig. 
arly, the standard 
1 0.5% in y to 1.15% 
‚amera is to know 
your processing. 
ntee right values 
taking the mean or the median. Another matter is the selection 
and application of robust estimators in the adjustment. 
6. CONCLUSIONS 
The most difficult task when using CCD progressive video 
cameras for measuring is to know which image should be 
captured, or how many images we need for averaging. 
Results obtained from this study show that the reliability on 
video cameras is very poor. Whatever parameter is analysed, 
the variability exists and could not be tolerable. Although there 
are many ways to calibrate cameras, the problem itself is the 
non-metric video camera, and not the right methodology of 
geometric calibration. Otherwise, this study would have shown 
promising results in these aspects. 
7. REFERENCES 
Dermanis, A., 1994. Free network solutions with the DLT 
method. ISPRS Journal of Photogrammetry and Remote 
Sensing, 49(2), pp. 2-12. 
Fraser, C. S., 1997. Digital camera self-calibration. ISPRS 
Journal of Photogrammetry and Remote Sensing, 52, pp.149- 
159. 
Gruen, A. Huang, T. S.(Eds), 2001. Calibration and 
Orientation of Cameras in Computer Vision. Springer-Verlag, 
Berlin, Heidelberg. 
Lerma, J. L., 2002. Fotogrametría Moderna: Analítica y 
Digital. Editorial de la Universidad Politécnica de Valencia, 
Valencia. 
8. ACKNOWLEDGEMENTS 
The research reported was partly sponsored by the Generalitat 
Valenciana, reference number GV00-091-6. The authors would 
like to acknowledge the financial support. 
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