Another use for all those neatly tagged photos of tourist attractions on websites like Flickr:
synthesising accurate 3D models from millions of photos, taken by amateurs from random angles:
To make the 3D digital model, the researchers first download photos of a landmark. For instance, they might download the roughly 60,000 pictures on Flickr that are tagged with the words "Statue of Liberty." The computer finds photos that it will be able to use in the reconstruction and discards pictures that are of low quality or have obstructions. Photo Tourism, a tool developed at the UW, then calculates where each person was standing when he or she took the photo. By comparing two photos of the same object that were taken from slightly different perspectives, the software applies principles of computer vision to figure out the distance to each point.
"We don't quite get the accuracy of a laser scanner, but we're in the ballpark," Seitz said. The recreations of Notre Dame show individual figures carved into the stone facade. A model of The Duomo in Pisa, Italy, a building about 160 feet tall, is accurate to within a few inches. The resolution of the 3D model mostly depends on the resolution of the original photos.
The next step in the research will be to create a detailed 3D model of a city entirely from automatically sorted photos from the internet; Rome has been chosen as the city to thus recreate.