You've probably heard of Photosynth by now, the rather fabulous technology from MIcrosoft Research that automatically stitches together overlapping pictures into a virtual world. You won't have seen it in action yet - although parts of it are probably in Worldwide Telescope - because, well, Microsoft has other things on its plate at the moment.
Today -- oops, how did that happen? -- Google has gone and quietly launched a much more basic, yet still tremendous fun, piece of software that does something rather similar but has the distinct advantage of being attached to a real application. It doesn't really have a name - there's a "Look around" tag that invokes it -- but you get to it through Panoramio, a recent Google acquisition which couples user-uploaded pictures to Google Earth.
Here's the blog where the feature is introduced. It's far easier to play with than to describe, but here goes.
When a photo's got a 'Look around' tag beneath it, click on that tag. That'll take you to a Flash application with the photo in it. Mousing over the photo will cause various quadrilaterals to appear, each of which describe the borders of other photos that share part of the one you're looking at. Click within one of those and you'll be smoothly mixed to the chosen photo - which has its own set of quadrilaterals, and so on. It's very addictive, and the frustration you feel when you've explored an entire photo set is real.
So - good work, Google. But there's one twist to the story. A Moscow chap called Vladimir Slepnev has previous created and GPL'd an apparently identical application called OpenPhotoVR.
As he points out, the coincidences are visible, technical and rather far-fetched. He mentions "the Jacobian trick for transitions (don't ask)" - so I had to go and look it up. He's right. Don't ask. Unless talk of first-order partial derivatives of a vector-valued function makes you warm, in which case ask someone else. But it's a very obscure mathematical function: I wouldn't like to speculate how likely it is that two people would independently choose it out of many more common transition functions, but I do see his point.
He's philosophical about the possibility -- probability -- of being an unrewarded, uncredited contributor to the Googleplex, and considers the honour of potentially being upstream of Google's source reward enough. Although he'd like his next gig to be somewhat more material in its compensation.
Reading this, Google? (of course you are.) Any comment?