How do this untwirl thing?? Filter? Post link please

I'd think it'd just be a matter of twirling in the opposite direction very carefully, but wtf do I know?

Anyone have a better idear?

It's got to be a simple matter of math. The twirl tool would use a mathematic algorithm to create a twirl in a given direction, at a given size. To reverse, in theory, you would only have to repeat the process - from the same center point - in the opposite direction. I'm willing to bet that anyone could accomplish similar results with a couple hours of trial and error. Hardly as 'high tech' as INTERPOL is making it sound in that story.

Same idea as this. As long as you aren't mixing the paths that the pixels follow it should theoretically go back to the same place. It's just a matter of getting the brush hardness and everything the same