Extracting audio from visual information

Algorithm recovers speech from the vibrations of a potato-chip bag
filmed through soundproof glass.

Researchers at MIT, Microsoft, and Adobe have developed an algorithm
that can reconstruct an audio signal by analyzing minute vibrations of
objects depicted in video. In one set of experiments, they were able to
recover intelligible speech from the vibrations of a potato-chip bag
photographed from 15 feet away through soundproof glass.

http://newsoffice.mit.edu/2014/algorithm-recovers-speech-from-vibrations-0804