irt BS. Istanbul 2004
ferences. It can be
in of simulated data
membered that the
)n were not entirely
———Ü———
7
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v
/
À
=
vd
75
T 3 |
^ c
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A
MÀ
'es respect to object
ata cannot be treated
ive depiction of how
et is, or is not, with
8. For this represen-
ine segments inside
sponding lengths of
| respect to nominal
8 the second order
f differences respect
nces in length is pre-
ir from origin. More
origin, more inaccu-
| on this assumption
nent is, more prob-
ts will locate farther
r lines is larger than
sential to notice that
nce is below 10mm
ble consistency with
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part BS. Istanbul 2004
nt pairwise. The dif-
f line segments.
5 CONCLUSIONS
In this paper the refined mathematical model has been re-
presented, which also encompasses possible deviation from
the ideal model of imaging in practice. Also self-calibration
technique has been applied in the estimation model on the
final stage. Acquiring initial values for parameters is quite
a straight forward procedure, which can partly be comput-
erized with simple instrumentation. Some attention has
to be paid to their correctness though. The method has
been tested in real close-range measuring conditions with-
out any optimization. Despite some unreliability in the ref-
erence data the accuracy with this method can be estimated
to be better or at least the same as with equivalent stereo
pair measurements. When the object space to be measured
is up to 20 — 30m the achieved accuracy of 0.01 — 0.02m
is quite adequate for large variety of applications.
However, in order to reveal the real power of this method,
further research work has to be done and more specific tests
have to be arranged where imaging and measuring con-
ditions are not the limiting factors. The presented method
is designed to be used for measuring surrounding object
space from the single point of location. However, more
than one such camera stations can be combined to achieve
more precise and geometrically improved constellation in
terms of measuring accuracy.
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