Photogrammetry Services
TreisTek offers a wide variety of photogrammetric services such as aerial photogrammetry and Digital Photogrammetric services to its clients worldwide. The aerial photogrammetry and digital photogrammetry services are obtained using aerial acquisition through digital orthophotography.
Earth Imaging provides solutions for the creation of digital maps, which are a gateway to a nation’s great wealth of resources. TreisTek acquires accurate images of the Earth from a host of sources, such as Aerial Photography, Laser Photography and Satellite Imagery. We offer a complete range of photogrammetric services for Municipal Mapping, Utilities Mapping, Road and Highway Planning, Cadastral Mapping, City Modeling, etc. Our services include consulting, project planning, software application development, image acquisition and processing, data conversion and integration.
Photogrammetric Solution and Services offered:
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Earth imaging services
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Triangulation – orientation and adjustment of a block
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Stereo data collection – feature mapping
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Terrain modelling and 3D visualisation
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Orthophoto
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Cartography – map finishing and publishing
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Thematic mapping using satellite imagery
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GeoSpatial services for photogrammetry and remote sensing
Aerial Triangulation
Aerial triangulation is the process of collecting intersecting points of the same feature on different images and placing points of known coordinates in order to establish the position and orientation of the images at the moment of the camera exposure.
The main objective of aerial triangulation is to produce from ground control, sufficient points in the photogrammetric models to ensure that each model can be oriented accurately as required for stereo compilation in either orthophoto or line mapping.
There are mainly three stages of aerial triangulation:
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Preparation
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Image measurement
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Block adjustment
TreisTek's aerial triangulation processing services cover all types of cameras.
Orthorectification
Orthorectification is the process of removing the effects of image perspective and relief effects for the purpose of creating a planimetrically correct image. The resultant orthorectified image has a continuous scale wherein features are represented in their 'true' positions. This allows for the accurate direct measurement of distances, angles, and areas. Orthorectified images are commonly used as in visualisation tools such as Google Earth, OSSIM Planet, ArcMap, WMS, etc.
The necessary inputs for orthorectification:
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An image with accurate sensor geometry
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An elevation model of the ground surface in DEM, DTED, or SRTM format
The resulting accuracy of the orthoimage is based on the accuracy of the triangulation, the resolution of the source image, and the accuracy of the elevation model.
Topographic and Planimetric feature extraction
Planimetric/Topographic mapping is a representation of the earth surface features in a 3D manner and used for geospatial analysis and modelling. Our advanced photogrammetry suite enables us to capture data from small to large scale stereo models and generate digital topographic maps of high precision.
TreisTek provides accurate digital planimetric feature extraction for cartography mapping and 3D topo mapping by extracting vector or point information of railroads, buildings, hydrological features, vegetation, etc., with corresponding ids and symbology.