As a a graduate student I had worked on a project where I used single particle imaging techniques to image the structure of a small viral protein. The protein particle fortunately has some symmetry, and using single particle image reconstruction techniques I could obtain a three-dimensional model of the particle from two dimensional projection images taken on an electron microscope.
After deepak got me hooked on to the TED talks , I caught a talk by Blaise Aguera Y Arcas on Microsofts new application called photosynth.
In the talk Blaise Arcas describes how they were able to put together a very high resolution almost three dimensional composite of the Notre Dame Cathedral assembled from tagged images on flickr.
Their software was able to accurately find the register for thousands of images from this tagged set and assemble it into the final composite. Check out the video above to get an appreciation of the complexity of the application. While I am hardly an expert in image processing, the algorithmic complexity of the application boggles my mind. Particularly impressive are the sections in the video where he talks about photosynth finding the register of images in the actual assembled composite despite them having people , hands and other obstacles obscuring the view of the cathedral.
I also caught some of the discussion on microsofts channel 9 on the technology. I sure would like to know the concepts they used to put-together such an amazing app. I also wonder of any of these concepts can help improve image reconstruction techniques in use in the single particle bio-imaging field.