GEOGRAPHY:
PHOTOGRAMMETRY & GIS
TREGEO has professionals with a pluri annual experience in photogrammetry, using newest technologies (DRONES) to take aerial photos we create high resolution ortho photomosaic and 3D point clouds, indispensable products to study the Earth and Human processes.
Through photogrammetry we can obtain geometrical data of the photographed objects. If we work with more than one photo, in the overlapped area we have a stereoscopic vision and we extrapolate 3d digital surface model (DSM) and ortho photomosaic.
We offer the following products:
Ortho photomosaic
An ortho photomosaic is a mosaic of aerial photographs corrected for optical distortions, georeferenced and orthorectified.
Otho photomosaic get a relative precision of up to 5cm (RSM X, Y, Z) and therefore can be used to measure distances and areas.
We offer high spatial resolution products: from 5cm / pixel up to 25cm / pixel
The data will be delivered in RASTER "full resolution": .TIF format and ECW compressed raster format.
DSM- Digital Surface Model
DSM (Digital Surface Model) is a surface 3D model with the information about elevation of all that is seen in the orthophotomosaic (trees, roof ...).
DSM is derived from the same aerial photographs processed with the latest photogrammetric algorithms.
We offer high spatial resolution DSM (Digital Surface Model: from 5cm / pixel up to 2m / pixel in raster format "full resolution": .TIF and vector format as point cloud .XYZ 1m.
cDTM (casi Digital Terrain Model)
The CDTM (nearly Digital Terrain Model) is a "nearly" digital terrain model with topographical information. CDTM is built from DSM through a filtering process with automatic interpolation and manual correction.
We offer high spatial resolution CDTM (almost-Digital Terrain Model) from 25cm / pixel are up to 2m / pixel in raster format "full resolution": .TIF and vector format as point cloud .XYZ at 1m point and contour from 0.5m in DWG. and SHP.
The generation of casi-DTM (nearly Digital Terrain Model) is in experimental state. The CDTM is derived from DSM by algorithmic estimation, 3D point extraction procedures and manual corrections in a post processing stage. Different surface objects (e. g. dense forest and shade)difficult to estimate and extract the DTM points simply because the photo sensor on board the UAV is unable to see what lies beneath the foliage or the shade of a dense forest. Therefore 3D reconstruction in these areas will be uncertain.
