I've heard about these movies for years but had never seen them. Interesting...and a little disgusting.
Basically, the films show high speed images of the lips vibrating as seen through a clear mouthpiece. Some big name players including Bill Watrous, Stuart Dempster, Larry Wiehe and George Roberts.
Thanks for David Wilken for getting this up onto YouTube.
Part 1: downstream embouchures
Part 2: upstream embouchures
Part 3: multiphonics