12.08.1406:45 AM
THE HUGE, UNSEEN OPERATION BEHIND THE ACCURACY OF GOOGLE MAPS
https://www.wired.com/2014/12/google-maps-ground-truth/
"Other algorithms extract building footprints and heights from satellite and aerial imagery. The majority of buildings in the U.S. are now on Google Maps. For landmarks like Seattle's Space Needle, computer vision techniques extract detailed 3D models (see below). Google has said that its recent acquisition of Skybox, the high-resolution satellite imagery company, at least initially, is to improve the accuracy of its maps."
