Airborne photogrammetry and lidar for DSM extraction and 3D change detection over an urban area – a comparative study

Cornelis Stal, Frederik Tack, Philippe De Maeyer, Alain De Wulf, Rudi Goossens
2013 International Journal of Remote Sensing  
Cornelis Stal and Frederik Tack equally contributed to this article and are listed alphabetically. A digital surface model (DSM) extracted from stereoscopic aerial images, acquired in March 2000, is compared with a DSM derived from airborne light detection and ranging (lidar) data collected in July 2009. Three densely built-up study areas in the city centre of Ghent, Belgium, are selected, each covering approximately 0.4 km 2 . The surface models, generated from the two different 3D acquisition
more » ... methods, are compared qualitatively and quantitatively as to what extent they are suitable in modelling an urban environment, in particular for the 3D reconstruction of buildings. Then the data sets, which are acquired at two different epochs t 1 and t 2 , are investigated as to what extent 3D (building) changes can be detected and modelled over the time interval. A difference model, generated by pixel-wise subtracting of both DSMs, indicates changes in elevation. Filters are proposed to differentiate 'real' building changes from false alarms provoked by model noise, outliers, vegetation, etc. A final 3D building change model maps all destructed and newly constructed buildings within the time interval t 2 -t 1 . Based on the change model, the surface and volume of the building changes can be quantified.
doi:10.1080/01431161.2012.717183 fatcat:tqm5asgzubdcjkr55rriqmjfye