Last July Aerodata Surveys completed the Change Detection project for the City of Amersfoort (the Netherlands).

By comparing high resolution digital aerial imagery of 2005 and 2006 (both 8cm GSD and acquired by Aerodata with its Ultracam-D), a series of shape files were compiled that contain changes in the built-up areas of the city, with a further classification into various construction types.

Using the methodology of computer assisted visual interpretation a very high degree of reliability could be achieved. Roughly 3.700 changes were found in an area of only 65 sq. km.

The data will be used for verification of the cities’ own license information system on building permissions and related tax information.