Processing of Aerial Photos

24. 10. 2007 — One of the first steps in the gathering of digital technical documentation when using analog cameras is almost always scanning (black and white or coloured). For the cartometric scanning of large-format basic maps, including aerial photographs, we use quality scanners with high accuracy and resolution.

Scanner

Processing

The scanned data usually need further modifications. WE will clean up your data, as well as crop, turn, transform them into the coordination system, adjust them and convert into the format most suitable for you.

For the creation of orthophotomaps, it is necessary to secure the projection plate centres with the help of analytic aerotriangulation (AAT). Planimetry and altimetry evaluation, edge measuring and DTM creation (digital terrain model) can be performed, if the customer requires it.

On the basis of the calculated parameters of the spatial coordinates of the image centers and the DTM the aerial images become orthogonalized (=transfer from central projection into orthogonal projection).

Out of these orthophotographs a so-called orthophoto-mosaic is created, where the images have to be colour-processed (radiometric and photometric – so called dodging) before being classified into the mosaic, so that the resulting product is colour-balanced.

In the upcoming phase the so-called seamlines are defined. They define the lines along which the various orthorectified images will be connected into the form of a mosaic.

The result of the processing are thus map sheets of individual orthophotomaps, usually in a form of big format maps.

Data and archiving

We deliver the raster data in all standard formats, based on the customer’s requirements (TIFF, CIT, PCX, RLE, JPG, BMP, SID, ECW and others) on different data carriers (CD-ROM, ZIP, DLT tapes et al.).

We will gladly help you with the selection of a suitable system for digital archiving and document administration for a larger volume of processed data and process the data for the selected software.

We have long-term experience in film processing and the production of diapositives, contact copies and enlargements that can be used for a wide range of applications including environmental research, city development, traffic system design and geographic data management.

We are ready to offer interesting discounts for regular customers with larger data volume. We will gladly process an offer for you for further adjustment of raster data, their transformation and vectorization.