A presentation in October at the International Conference on Computer Vision showed how photos from online sites such as Flickr can be used to create a virtual 3D model of landmarks, including Notre Dame Cathedral in Paris and the Statue of Liberty in New York City.
"The big breakthrough here is being able to compute very accurate 3D models from people's vacation photos," said co-author Steve Seitz, a UW associate professor of computer science and engineering. "The long-term vision is to be able to reconstruct the detailed geometry of all the structures on the surface of the Earth. Many people are working toward that goal, but by using online collections this work brings in a whole new source of imagery and level of detail."
Online photo-sharing Web sites such as Flickr and Google are popular because they offer a free, easy way to share photos. Flickr now holds more than 1 billion photos; a search for "Notre Dame Paris" finds more than 80,000 files. The study authors, experts in computer vision, believe this is the world's most diverse, and largely untapped, source of digital imagery.
But the freely available photos do present a challenge: these are holiday snapshots and personal photos, not laboratory-quality research images. While some may be postcard-perfect representations of a setting, others may be dark, blurry or have people covering up most of the scene.
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.
"The general principle is very similar to how our eyes work," said lead author Michael Goesele, a former postdoctoral researcher at the UW who is now a professor at Technische Universität Darmstadt in Germany. "You get multiple views from different points of a scene, and then you find the same point in different views and infer from that the depth of the object."
In tests, a computer took less than two hours to make a 3D reconstruction of St. Peter's Basilica in Rome, using 151 photos taken by 50 different photographers. A reconstruction of Notre Dame Cathedral used 206 images taken by 92 people. All the calculations and image sorting were performed automatically.
"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.
Creating 3D reconstructions of individual buildings is a first step in a long-term effort to recreate an entire city using online photographs.
"We've downloaded about 1 million photographs of Rome from Flickr," Seitz said. "We want to see how much of the city we can reconstruct--including exteriors, interiors and artifacts." The group hopes to make significant progress on the Rome project over the next couple of years, he said.
Other co-authors on the recent paper were Noah Snavely, a UW doctoral student in computer science and engineering; Brian Curless, a UW associate professor of computer science and engineering; and Hugues Hoppe, a researcher at Microsoft Research in Redmond, Wash. The research was funded through grants from the Alexander von Humboldt Foundation, the National Science Foundation, Microsoft Research and Adobe Systems Inc.
Hannah Hickey | EurekAlert!
Rules for superconductivity mirrored in 'excitonic insulator'
08.12.2017 | Rice University
Smartphone case offers blood glucose monitoring on the go
08.12.2017 | University of California - San Diego
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications
Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...
Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.
The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...
Transistors based on carbon nanostructures: what sounds like a futuristic dream could be reality in just a few years' time. An international research team working with Empa has now succeeded in producing nanotransistors from graphene ribbons that are only a few atoms wide, as reported in the current issue of the trade journal "Nature Communications."
Graphene ribbons that are only a few atoms wide, so-called graphene nanoribbons, have special electrical properties that make them promising candidates for the...
08.12.2017 | Event News
07.12.2017 | Event News
05.12.2017 | Event News
08.12.2017 | Life Sciences
08.12.2017 | Information Technology
08.12.2017 | Information Technology