Building Rome in a Day
The billions of photos taken in cities across the world and uploaded to places like Flickr, Photobucket et al might suddenly have a very interesting use. The University of Washington are experimenting with the creation of 3D “point clouds” similar to those created by terrestrial laser scanners, from downloaded images.
By sourcing images and applying the principles of photogrammetry and distributed computing, the results are very impressive. They aren’t going to rival laser scanners just yet, but the animations on the Building Rome in a Day project website are impressive, and show the huge potential of this approach.
Entering the search term Rome on Flickr returns more than two million photographs. This collection represents an increasingly complete photographic record of the city, capturing every popular site, facade, interior, fountain, sculpture, painting, cafe, and so forth. It also offers us an unprecedented opportunity to richly capture, explore and study the three dimensional shape of the city.
This particular project aims to create “sparse point clouds” to give a 3D overview of the layout of a city, and has interesting potential for interacting with and exploring a place virtually. They are running a parallel project investigating dense point clouds which looks promising, but probably won’t see any popular use for a long time due to the massive amount of processing and data storage involved (dense 3D point clouds and meshes are huge datasets).
The University of Washington project is similar to Microsoft’s Photosynth project. But the difference is that with Photosynth, users have to manually create “synths” by uploading photos of a particular place. Photosynth does not allow users to tap into the millions of other images out there, which moves me to my next point.
What about the copyright implications of crowd-sourced photos? Even if just using Creative Commons licensed images, imagine what the “attribution” page would look like if hundreds of thousands of images have been used from potentially tens of thousands of photographers. I’ll be interested to see how they deal with that side of things.
But overall, this is an exciting development. There is huge potential for cultural heritage applications, especially in the areas of survey and interpretation. I will be following this project very closely.
Bill Hume, 
http://www.flickr.com/photos/george/
Cool…undoubtedly and no doubt usefull in a global recording sense. It does however remind me of Photosynth in that the point clouds are unobtainable to us mere mortals. I had hoped for a system like ’synth where I could input photographs and have a point cloud constructed from them. Yes I know ’synth does that, but there is no mechanism for obtaining the point cloud data. It’s so frustrating.
See
http://photosynth.net/view.aspx?cid=40f024dd-d24e-4d97-a530-501faefc639f
It’s a synth of a standing stone I made last year. I love the point cloud, I can see it, but can’t obtain it as a data set. Let’s hope someone at Microsoft sees the real value of Photosynth soon.
Bill Hume.