Automated Architecture Reconstruction from Close-range Photogrammetry 
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Figure 7: (a) The lines of intersection of the three computed planes projected onto the third image of figure 1. (b,c) Two views of the 
texture mapped coarse 3D VRML model, consisting of wall planes and the ground plane, partially delineated. The automatically 
computed 3D model augmented with indented windows is shown in (d) untextured, and texture mapped from the appropriate regions 
of the images in (e) and (f). Observe the difference between windows not modelled (b,c) and modelled (e,f) as the viewpoint 
changes. 
The keypoints labeled by thresholding as being behind the wall are shown in figure 5d. Contiguous regions (corresponding to each 
of the windows and doors) are then computed by robustly clustering these points. The fitted plane has essentially simplified this task 
to that of clustering a set of pixels in a 2D image as the analysis can be carried out on a rectified version of the image (where the 
principal scene directions are orthogonal in the image). Standard image processing methods, such as simple operations of binary 
morphology, are used. Rectangular boxes are then fitted to the clusters. The resulting windows boundaries are shown in figure 5e. 
Figure 8: Four views of one side of the Zurich City hall which are used in the plane sweep to determine the window indentations.