Photofly runs through several steps to distill an accurate model from a collection of photos. First, it calculates the position from which each photo was taken by triangulating based on the different views of certain distinctive features. Once the camera positions have been determined, the software goes through a second round of more detailed triangulation, using contrasting views to generate a detailed 3-D surface for everything visible.
“This technology and the popularity of cameras and cell phones means there are now a couple billion sensors out there that anyone can use to create 3-D content,” says Yuan-Fang Wang, a computer scientist at the University of California, Santa Barbara, and founder of VisualSize, which is working on technology similar to Autodesk’s.
Wang says the technology has become robust and simple enough for the consumer market, but there are still limitations that may frustrate some people. “An object cannot be too plain, because the software has nothing to compare, or too shiny, and it cannot be moving much,” he says. Because few ordinary users have experienced the technology yet, it is still unclear how people will handle that, or just which applications will prove popular, Wang adds.
Photofly can be used on objects large and small, from bugs to buildings, and can also handle photos from different sources. A video shows a model of Mount Rushmore created from a variety of online images taken by many different people.
After seeing a demo of the technology at the TED conference earlier this year, paleontologist Louise Leakey has been using Photofly in Kenya to capture early human bones at high detail. The models provide her team with a way to collaborate with distant colleagues and to record accurate measurements of specimens, such as the spacing and size of teeth, without actually handling them (see a video of a specimen captured by Leakey).
Autodesk will also explore using Photofly to capture 3-D models of buildings to speed retrofits designed to boost their energy efficiency. “You can take a bunch of photos and very quickly have a model to make the key measurements needed to figure out what needs to be done to make a building greener,” says Mathews.