3D pointclouds - 3D models - Orthophotography
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Pointclouds Whatever the 3D sensor, the first result of a 3D scanning process is a raw data file containing series of 3D coordinates, what we call a 3D pointcloud. We rarely provide this type of product, because they are raw data and very few software are able to manage them. Our customers rather expect finished products such as maps, 3D models or true orthophotos. But when it is asked, we can provide consolidated pointcloud and a free 3D viewer. 
High density 3D models Our processing software can connect the 3D points by triangles. The result is a 3D mesh, a true digital skin that rebuild the geometry of the scanned surface. The mesh can completly cover the scanned object. From this 3D archive, any geometrical information can then be extracted : coordinates of points, distance, slope, radius, contour lines, cross sections. The model can also be textured to add the information of color. It can be exported in several digital formats supported by CNC machines for the manufacturing of plaster or resin models. 
3D textured models These 3D models are much lighter than dense 3D meshs. The object is modelized with geometric primitives (plans, cylinders or spheres, cones, splines,...). These primitives are digitalized in the 3D pointcloud by using special tools. Calibrated photos are used to texture. The resulting model looks like the real object in a very realistic way. It is not necessarily accurate, but it offers an easy solution to manage 3D for 3D rendering or virtual tours. 
Maps Cross sections, curves and contour lines : the result here may seem identical to classical restitutions, but the contribution of 3D scanning lies in the fast recording and especially in the density of information returned. Mapped lines stick to reality. We also use our accurate 3D models to provide maps with color gradient. 
Orthophotography
A camera distorts the geometry of the object it records. These distortions are due to perspective, the relief of
the object and lens imperfection. A photo is a document with an undeniable density of information. Within the
limit of image resolution, all that is visible is represented.
It is possible to correct the distortions. We have developed a software that put every pixel of a photo at its
true position in an accurate geometric projection plane. This operation called orthorectification leads to the
production of a document as accurate as a map, and as rich as a photograph: a true orthophotography.
Our orthorectification process can handle very large distortions and can lead to very accurate orthophotomaps
(1/20 scaled maps with 1 pixel every 2 mm for example). We have also adapted this process to developed surfaces of revolution (cylindrical towers and tubes, conical surfaces, domes).
Thanks to our special process, we guarantee the accuracy and richness of our orthophoto documents.
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