[future_grad]

There is a way that scientists have been able to analyze photos to discover the pulse of the person in it. Its very interesting, though I do not know the deeper details of it.

I am too lazy to find a link, if anyone else wants to share it that would be great.

[hfsktr]

This?

http://web.mit.edu/newsoffice/2012/amplifying-invisible-vide...

[nitrogen]

I believe the term they use is "Eulerian magnification": http://people.csail.mit.edu/mrub/vidmag/