The IFSAR radar scans the earth surface during the aerial photography and the result of the processing are the following products:
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ORI (Orthorectified Radar Images) - grey-shaded image with a 1,25 metre pixel size. ORI look like panchromatic images. Those are radar images acquired with the IFSAR sensor and differentially repainted.
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DSM (Digital Surface Models) -
Surface model with a 5 metre grid and 1 metre elevation accuracy. The surface model contains elevations given by the first reflection of the radar signal from the earth’s surface. -
DTM (Digital Terrain Models) - Terrain model with a 5 metra grid and 1 metre elevation accuracy. DSM is the foundation for the creation of DTM, which is created by the elimination of the elevation of artificial and natural objects in the terrain.
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CORI (Colour Orthorectified Radar Images) - ORI coloured by a multispectral image, with a 1.25 metre pixel size. CORI are ORI radar image coloured with the help of a different multispectral image.
ORI
Orthorectified
Radar Image (ORI) is a panchromatic image of earth’s surface.
Geometric distortions are eliminated by differential repainting in
the ORI.
This product shows the earth’s surface in a
manner that it designs the objects more distinctively than classic
aerial photography. The radar images are oblique, so that it displays shades,
which enables the user to perceive the height zoning in the
photograph.
ORI are suitable for:
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object mapping, like road network, water-courses and water surfaces, buildings, vegetations, et al.
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as a foundation for topographic mapping, land cover mapping, telecommunication flooding, forest and geological analysis.
ORI are geometrically
and chronologically concurrent with the elevation data.
The
accuracy of the ORI image is 1.25 metres.
CORI
Combined photograph that
conserves its spectral integrity of the Landsat image at the increase
of the spatial resolution. Pan-sharpening is a process, where the
colour information of a low-resolution photograph is connected to a
high spatial resolution of the panchromatic image.
CORI is
connection of a low-resolution photograph with an high-resolution
ORI. The resulting product has the same accuracy as the ORI.
The
accuracy of the CORI is 1.25 metres.
DSM
DSM (Digital
Surface Model) is an elevation model, which represents the first
reflections of the micro-wave beam from the terrain or object in the
terrain in a regular grid. DSM is dependent
on the wave-length (X-Band: treetop, P-Band: terrain under
vegetation.
DTM (Digital Terrain Model) is a product derived
from DSM in the Intermap technologies. It’s a model, where the
elevation represents the elevation of the terrain.
DTM processing
includes terrain edges and irregularly distributed 3D vectors that
suitably represent bare terrain.
DSM is a topographical model
of the earth’s surface. It’s a raster with a 5 metre pixel size.
The radar beam reflects off the first object it meets, which creates
the representation of any object that is large enough to be
registered. Buildings, vegetation, roads and all the other objects in
the terrain are included. The DSM represents a geometrically correct
referential framework, on which data of other layers can be
displayed.
DSM is suitable for:
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a whole line of application, e.g. the creation of 3D transits, visibility anylisis, in navigational systems, forestry and other.
DTM
Digital Terrain
Model (DTM) is a digital representation of the
bare earth’s surface derived from the DSM. In DTM the elevation of
vegetation, buildings and other objects in the terrain are eliminated
and it represents the terrain elevation under these objects. This is
achieved with the use of Intermap’s own software, which allows to
interpolate the terrain elevation based on the surveying and
indentification of the bare terrain in the source DSM.
Thanks
to the basic featured of the DTM we can derive the terrain
characteristics, which can be hidden in the DSM.
DTM
is suitable for:
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application support like the creation of topographical maps or flood modelling,
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terrain analysis like profiles, cross-sections, drift direction, drift and application for vehicle move.
