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A couple friends of mine wrote an extremely mathematical analysis of the rolling shutter effect, and even looked at some related questions like "given a photo from a rolling shutter how can you tell how many propellor blades actually exist and how fast it is turning?".

http://danielwalsh.tumblr.com/post/54400376441/playing-detec...

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>and even looked at some related questions like "given a photo from a rolling shutter how can you tell how many propellor blades actually exist and how fast it is turning?"

I've seen some code (don't remember the website now) that gets you the non-rolled shuttered (sic) image from the rolling shutter one.

(It works to reconstruct a scene, but has issues at edges etc, so it's not really usable to fix a photo/video 100% -- but there are commercial NLE plugins that do reduce rolling shutter in post).

One concrete example: the most recent version of Autopano Video Pro does rolling shutter compensation as part of its stitching of 360 video from a rig of GoPro cameras.

Thanks for posting that - nice add to my collection, and I'd argue they work out some of the math far more than others (it's implied in other places, but its nice they actually worked it out instead of another bloody exercise for the reader) :-)

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