Time-Folded Pelicans

Wait, what?

These pelicans are time-folded at half a second. They are diving off the stern of the CMB Biwa, moored at Astoria late in September 2012. (Most of the birds are actually gulls, but it’s the pelicans that interest me most.)

No, seriously, explain this

Gee, what’s to explain? The CMB Biwa is a Belgian-flag bulk carrier out of Antwerp, IMO 9267417. It was involved in an accident in Rìzhào, Shāndōng, while carrying coal in May 2005. Here’s a video of it under repair. Most likely the birds are eating fish that school in the slack water at its wake. When the—

But seriously, though

Take a 30-second video of birds flying around. Imagine it as a physical piece of film: 30 seconds × 30 frames per second = 900 frames. Now cut the film every half a second (15 frames), stack these short clips, and run them through the projector overlapping. That’s essentially what this is.

More technically, it’s a lighten composition (pixelwise maximum) on all frames such that frame number % 15 = n for n in 0 through the number of frames ÷ 15. (I tried with 30 instead of 15 and it was different but also interesting. Presumably it will depend a lot on the subject; this is the first thing I tried.) You can spot that it’s a simple lighten instead of something more sophisticated if you look at the pelicans just as they dive – when they should be dark gray, they disappear.

It doesn’t work!

Firefox doesn’t support the video format. Sometimes Safari and Chrome flicker a little as they loop.