tem was
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/tilt unit
dividual
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20 gons
lined by
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cated by
its being
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the unit
OX.
bines the
fine the
Camera
metry of
/tilt unit
X Harley
which
Infra-Red
Electro-optical
Distance measuring
unit (EODM)
Secondary
rotation axis
Optical encoders
(€ 1 arc second)
Pulnix CCD cameras
'Pointing' camera with
narrow FOV
‘Context’ camera with Ë : Sr
wide FOV E
Servo Driven Pan/Tilt Unit
(Geotronics 460)
Primary
rotation axis
Optical encoders
(€ 1 arc second)
Figure 5. The HAZMAP remote measurement unit
relates to the pointing of the CCD camera is acquired
with each image tile and written to the image header.
For the localisation of the hybrid camera a reduction to
centre computation is carried out within the extended
bundle adjustment module. This converts directions
observed at the eccentrically mounted CCD cameras to
equivalent directions at the rotation centre of the pan/tilt
unit.
Image measurement tools allow the determination of the
image coordinates of target points using the graphics
screen and mouse pointing device of a standard graphics
workstation. Images may be displayed as individual
tiles, a panoramic mosaic or as tile segments on an
image 'paste-board'. Image enhancements such as
hardware zooming and contrast stretching allow for
identification of image coordinates at the single pixel
level, centre of gravity operations allow the automatic
measurement of appropriately targeted points with a
precision of € 0.1 pixel. Facilities also exist for the
injection of geometrical primitives into all appropriate
view for the rapid manual determination of best fitting
objects and their export to the CAD system (Figure 6).
The orientation and transformation toolbox required for
geometrical evaluation of the image tile measurements
utilises the direction observations and all available
information from object space (e.g. dead reckoning
information, distances, directions) to derive a suitable
