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Extracting audio from visual information

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Re: Extracting audio from visual information

#131

Earlier quoted context omitted.

You missed the part where 60 frames per second only allowed to identify the speaker and the number of people in the room. > Because of a quirk in the design of most cameras’ sensors, the researchers were able to infer information about high-frequency vibrations even from video recorded at a standard 60 frames per second. While this audio reconstruction wasn’t as faithful as it was with the high-speed camera, it may s…

If you watch the video in the post, the demo is surprisingly accurate.

The demo in the video is based on a high-speed (1000+fps) recording by a special camera, not on 'normal' video.

Re: Extracting audio from visual information

#132

How much vibration does sound actually cause an object. I tried humming near various objects and noticed nothing. I used to be really interested in early mechanical microphones and sound recording, but I couldn't find much information on how they work either.

Your eyes wouldn't be able to see a 2000 Hz vibration, most vibrations that we perceive as sounds (except from the very low vibrations) are so fast that even with a huge amplitude they'd be just a motion blur for our eyes.

Now, a 2000 fps camera can see things that a naked eye can not.

Re: Extracting audio from visual information

#133

How much vibration does sound actually cause an object. I tried humming near various objects and noticed nothing. I used to be really interested in early mechanical microphones and sound recording, but I couldn't find much information on how they work either.

Your eyes wouldn't be able to see a 2000 Hz vibration, most vibrations that we perceive as sounds (except from the very low vibrations) are so fast that even with a huge amplitude they'd be just a motion blur for our eyes. Now, a 2000 fps camera can see things that a naked eye can not.

But I should see a blur or something, unless it happens to be vibrating at exactly the frame rate of both of my eyes (and even that would cause some weird effects, see helicopter blades spinning.)

Almost missed your comment btw.

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