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by mozumder 3072 days ago
Isn't this how those laser microphones work?
3 comments

It's the same concept of detecting vibrations, but obviously this method is using a camera and processing a video, while the "laser microphone" [0] measures the difference in distance traveled by the laser beam.

It would be interesting to compare the two methods in various scenarios, i.e. through glass.

Obviously the laser method will work at night while the video method will not (probably depends how "dark" it is).

[0] https://en.wikipedia.org/wiki/Laser_microphone

This is passive, laser microphones are active. I think another difference is laser microphones use motion parallel to the axis of the beam, whereas this is motion in the plane perpendicular to the line of sight.
Yes.