Imagine you could walk through all flickr photos of the Notre Dame in Paris in 3D. Photo tourism is a bit like Google Earth for photo collections. It basically generates a 3D model based on photos taken at the same location. They don’t have to be taken in a certain way and can be random tourist photos. This software recognises key points in all the images and calculates the view point of the photo. Anyway, you have to see it for yourself because it’s hard to describe. A good start is to watch this video and then try the live demo here. Since Microsoft is involved in this research as well, they are developing their own software based on this technology. It’s called photosynth, which you can test drive here. Simply amazing!