As part of its open data initiative, the city of Basel maintains and provides public access to an image bank of buildings. You can learn more about the Basel building database here.
The building gallery could be useful to you in creating an AR experience for citizens and visitors, or for the city employees based on the recognition of the building's features in a video. Unlike the other Land and Survey data sets which are confined to only the area around the Messe Convention Center and the Old City Center, this data is for the entire city.
To access the Basel building gallery images, first, download this file.
The root link (below) together with the extension found in the column labelled "DATEI" produces the URL directly to the picture
http://www.bs.ch/bildergalerie/1/ (for medium pictures)
http://www.bs.ch/bildergalerie/2/ (for small pictures)
For example:
http://www.bs.ch/bildergalerie/1/58937-rheingasse-59-001.jpg (medium)
http://www.bs.ch/bildergalerie/2/58937-rheingasse-59-001.jpg (small)
If you use any of the images from the gallery, the credit must read "(c) 2011 http://www.bs.ch/bilder"