125
their visibility (these fragment may be shielded with
relief or on-ground objects)
3) Using only selected “favorable” fragments (more
accurate their projections into the photo planes) the
stereo model is produced, which now is free from
miscorrelation problems. Of course such a model is not
full, because it is made up from the fragments. But it is
not a problem within this approach, because the model
has only auxiliary meaning contrary to classical method.
4) After that the produced during the previous stages
model is finally orientated relatively laser DTM, that
corresponds its orientation in geodetic space. Naturally,
the orientation of each frame is implemented also.
As already mentioned the presence of GPS principal
point coordinates of each photos is strictly determines
the stereo pair position in space with only one free
angle of turning around survey basis vector. So the
final true stereo model orientation relatively to DTM may
be done by minimization of spatial misalignment
function for both these surfaces. This may be
calculated with R.M.S. method, for example.
CONCLUSION
The conclusions of the present work have only passed
the very first experimental testing. The nearest plans
include creation of complete photogrammetric PC
oriented software package providing the entire set of
algorithms for visualization, topologic and
photogrammetric integral processing of laser and photo
data in digital mapping. Such package appearance
would symbolize a quality step of the presented
technology from experimental phase to actually
productive.
References
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