Kazuo Oda
P P hi^ : ; ; ; ; ia 1.
2 and E" ^ jin equation (15) can be analytically determined with the equation (3) and (4). In digital image process.
1
I 8 ;
ing image values are given by pixel values / x Ppix Ppnt . Thus ——— and —— can be denoted by following equa.
: phtl pht2
tions:
5 n. I ul Pix! I, = Tpix2 Prix2
Poht 1 Pix! Pphti Poht2 Prix2 LE. (16)
L3 b uc ns ; A Prix] Ppix2
PIX and -22 correspond to differential images in column and row directions. PP” and —P*- can be calculated
pix! pix2 phtl pht2
from the relationship between P i and P, nt » Which can be affine or projective transformation if optical distortion or
X
film deformation is negligible.
2.4 Variation of Optimization under Restriction
2.4.1 Optimization under Epipolar Geometry: Suppose that Epipolar geometry between the two images are known,
i.e., relative rotation matrix &,,, and direction vector [ b, e] from the optical center of 7, to the optical center I, arc
given. In this case the target parameters Eall have 7 degrees of freedom which is:
Eall = [3 7 =r, P, L}= T ı ı 1% Yı2; j (17)
t
where L is a scale parameter. The absolute parameters E, = i T, f P, can be derived from the following equations.
R T, Roi À 7] (18)
t
PoRL ORT, ran] +o, (19)
. e
Instead of equation (14), Fall can be expressed as follows:
e … | © er I I, I, (20)
Eall "L = d
a FE, L E, E, L
where
E = 4; Fons n = Amy Poni E, I - Mas Phi? E;
E; Puit, E; Pp E E, L ‘Poiuz fa L (21)
2.4.2 Optimization with fixed parameters: Suppose that ith element value of Eall (E;) have been fixed and other
unknown parameters should be optimized under this condition. This problem can be solved simply by setting O to € in
i
t
Jacobian matrix. The element A A ji is also set to 1 in convenience, to avoid deterioration in rank of matrix '4 A
in the equation (11). This derives that E; — 0 and optimization procedure does not renew the element £;.
This situation can be applied to conditions with combination of any fixed parameters, for example, when absolute paran
eters of one image are known, or when two optical centers are measured by, for example, GPS. It is recommended to us
any restriction to compute DSM based orientation since restriction brings robustness to the result.
654 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B3. Amsterdam 2000.
3. TEST
3.1 Test
The algor
the first s
ing point
geometry
rithm on t
computed
was used
Figure 3 1l
the figure
orthophot
3.2 Precis
The precis
precision c
tests result
method is |