Picking up audio using high speed video? In the movie Eagle Eye, ARIIA (an intelligence-gathering supercomputer/AI) picks up audio using video recording of the vibrations in a coffee cup. How close is this to reality?
I have see it done with laser on a window, and in theory I would imagine you could pick up 5 kHz audio by recording the vibrations with a 10,000 fps high speed hi-res camera.
Has it been done? How is the quality? What are the theoretical limitations? What are the practical limitations?
 A: In today's news - researchers at MIT did just that using high-speed camera with frame rate between 2 kHz and 6 kHz. They used some advanced filtering to detect microscopic movement of objects, but for details we will have to wait until they publish their paper.
A: In principle, there is now reason that this can't be done.  There are, however, a lot of practical difficulties.  


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*You would need a high speed camera recording at something like 50,000 fps to catch all of the audio band which humans can hear.  These things aren't cheap and generally can't record for longer than a few tens of seconds at such high speeds.  In contrast, laser vibrometers are relatively cheap and easy to build.  

*The surface you will be watching needs to have large contrast changes from the incident pressure waves.  Your example of the coffee cup probably would not work (unless the sounds were incredibly loud), it would need to be something more sensitive to pressure changes, like the diaphragms used for speakers, with light reflecting off of it in just the right way.

*The mechanical system which was responding to the pressure wave would need to be free of mechanical resonances in the audio band, or the mechanical resonances would need to be calibrated out.  
All in all, I would say that this is a poor way to try and record sound, but it isn't a complete impossibility.  I don't know of any cases where it has been done in the past.
