'- N '■
f evati °n should
Z®, the î
¡.As Figure h
is 1 pixel; and
nore I
line and p’i
ecision can be
lines, zoom m
vs . These lines
;econ(i °“
0 w coordinate,
1.7 pixels and
ïerence in r0 ' v
coordinate is 7.3 pixels. Therefore, the epipolar pairs do not
exist for the entire scene, but exist locally. This conclusion
consists with the property of epipolarity derived by Kim (2000).
Thanks for the supporting from the 973 Program of the People’s
Republic of China under Grant 2006CB701302 and the
National Natural Science of China under Grant 407721001.
The number of epipolar line on let scene
Figure 6. Accuracy of epipolar lines on the left scene
. REFERENCES
Cho, W., Schenk, T., and Madani, M., 1992. Resampling digital
imagery to epipolar geometry. International Archives of
Photogrammetry and Remote Sensing, 29(B3), pp. 404-408.
Sohn, H., Park, C., and Chang, H., 2005. Rational function
model-based image matching for digital elevation models.
Photogrammetric Record, 20(112), pp. 366-383.
Hu, Y., and Tao, V., 2004. Understanding the rational function
model: method and applications.
http://www.geoict.net/Resources/Publications/IAPRS2004_RF
M2394.pdf (accessed 16 Feb. 2008)
Figure 7. The difference among the seven epipolar lines
Kim, T., 2000. A study on the epipolarity of linear pushbroom
images. Photogrammetric Engineering and Remote Sensing,
62(8), pp. 961-966.
5. CONCLUSIONS
After analysing the epipolar geometry of linear array scanner
scenes a method which can be used to generate the approximate
epipolar line for linear array scanner scenes based on the
forward and inverse transform of RFM was developed. The
method proposed does not require DTMs or ground control
points during the generation, but it is better to know the range
of elevation of the area the scenes covered which can improve
the accuracy of the epipolar line generated. A stereo pairs of
IKONOS imagery are used to validate the feasibility of this
method; the epipolar generated can achieve a precision better
than 1 pixel which can meet the need of image matching. The
existence of epipolar pairs are also discussed, the result of the
experiment shows that the epipolar pairs do not exist in the
range of entire scene, but exist in a small range.
Orun, A.B., and Natarajan, K., 1994. A modified bundle
adjustment software for SPOT imagery and photography
tradeoff. Photogrammetric Engineering and Remote Sensing,
60(12), pp. 1431-1437.
Okamoto, A., and Fraser, C., 1998. An alternative approach of
the triangulation of SPOT imagery. International Archives of
Photogrammetry and Remote Sensing, 32(4), pp. 457-462
The epipolar lines generated in this paper can be used in image
matching, but the epipolar lines generated in this paper are
approximated, the true correspondence point may not lie on the
line but locate near from it. So the searching area for
correspondence should be defined not just along the epipolar
line but should be wider than it.
Recommendations for future work include performing more
experiments using more data such as SPOT and QuickBird