MIT was able to reconstruct voice by filming a bag of chips on a 60FPS camera. I would hesitate to say how much information can leak through.

https://news.mit.edu/2014/algorithm-recovers-speech-from-vib...

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hinkley 9 hours ago | parent [-]

I befriended the guy in high school who built a Tesla coil. For his next trick he was building a laser to read sound off of plate glass. The decoder was basically an AM radio. Which high school me found slightly disappointing.

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bcrl 4 hours ago | parent [-]

I basically asked my math and physics teachers in high school what the Fourier transform was, but none of them knew how to answer my questions (which were about digital signal processing -- modems were important things to us back in the early '90s). If I had to do it over again, I would have audited the local university's electrical engineering and math courses in evenings. The first time MIT ran 6002x online back in 2012, the course finally answered a lot of those questions when touching upon filters and bandwidth.

	▲	hedgehog 2 hours ago \| parent [-]
		Yeah I wish I had known about or had access to that stuff when I was a kid. To really learn and internalize ideas like negative frequency early would have been quite fun.