Fig. 7 Color-coded point cloud from image matching
Fig. 8 Differential DSM between laserscanning and image matching—new buildings are
painted in red and areas under construction in violet
At the first data acquisition in 2012, a DOP from 2003, LiDAR-data from 2007
and an up to date building ground plan from the cadaster were available. During
the first data acquisition, which is described in Sect. 2.2 , the operator has to con-
sider the most actual information, which is the building ground plan saved in the
cadastre in order to assure building ground plan constancy. Due to missing height
information from the LiDAR-data the building is calculated with a standard height
of 9 m (Fig. 9 ).
The determination of a standard height for the building causes that this building
needs to be post-edited, as soon as the DSM generated from the Bavarian pho-
togrammetry campaign is available. Such buildings are candidates for the timed
space closure, to avoid an extensive terrestrial surveying of the roofs. For those
buildings, which need to be post-edited, the regular DSM derived from Image
Matching has to be used instead of the LiDAR-data in the acquisition software
“Building Reconstruction” of the vendor VCS. In the following processing of the
same building ground plan, the result is a building with an up-to-date detailed roof
structure (Fig. 10 ).
The presented method of the timed space closure also allows the post-editing
of buildings which were built after the LiDAR-flight to accomplish the first data
acquisition of the 3D Building Model of Bavaria at a certain deadline.