Cycle Na
Image strip As VIN Image point
XA; YA
MEET
nn
=
Cycle Ng
Image point
Xg, ¥8
Image strip Bg
Cycle Nc
image point
Xc, Yc
Image strip Cs
Vv
Figure 5. Correlated image points in the image strips
2.3 Model compilation
Correlation is followed by the determination of the orientation para-
meters in the so-called update points P. along the flight course and of
the DEM points P: in a closed and rigordus analytical process of bundle
adjustment.
This is performed by the setting up collinearity equations for the
three rays belonging to one DEM-point. They are formed by the corre-
lated image points, the perspective center and the intersection DEM-
point Ps. They are of the following form:
; a 44 0,79) 8324 (07 Yu) 8244 (Z; 7 ZA)
: = F {p:, k:)
i,N S J ? x "4 1
a43(X, 7X) *854(Y,- Yu) $244 CZ; 7Z)
(1)
a4o(X;7Xu)85o (Y: 7Yu)*8425(247Z4)
=) € 12 1 IN 22 1ONN 30 libr F (pss Ki)
a43 (X; 7X4) 8854 (Y; 7 Yu) 245 (Zi Z)
Here c is the focal length, X, Ye L, are the coordinates of the in-
stantaneous scan position of the camera for Pi at the image cycle Nps
No: Ne» and 44 «+. Azz are the coefficients of the matrix of rotation
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