Somewhat reminds me of this hoax from over a decade ago: http://itre.cis.upenn.edu/~myl/languagelog/archives/002875.h...
If you watch closely enough, everything is a speaker
41–50 of 54 posts
Re: If you watch closely enough, everything is a speaker
#42I was wondering about using smartphone cameras as drum-head pickups, but the frame-rate problem put me off the idea. With the rolling-shutter trick it seems that it might be almost useful on bass drums, at least as a trigger rather than an audio source.
I used to be a sound engineer for live shows. I could imagine high speed cameras being used to replace instrument microphones in live performances one day, much like optical mice replaced the roller ball style.
By keeping a fixed object in view of the camera (e.g. a reflector on the stage), a camera could correct for its own vibrations and achieve perfect rejection of outside noise, unlike most microphones which have a cardioid pattern.
Probably a pipe dream, but cool idea.
Re: If you watch closely enough, everything is a speaker
#43Impeached Arizona governor Evan Mecham (shortened term 1987-1988) was probably very paranoid during his time in office, but nobody gave credence to his concern over the possibility of "reflected laser use" to surveil him. From Wikipedia ( https://en.wikipedia.org/wiki/Evan_Mecham ) ... Throughout his administration, Mecham expressed concern about possible eavesdropping on his private communications. A senior member o…
I couldn't find that comic, but I found this one.
http://www.gannett-cdn.com/-mm-/2ba3d3962352679dc5b6027b21e4...
Rose is Evan's successor.
Re: If you watch closely enough, everything is a speaker
#44Earlier quoted context omitted.
But leafs shake because they receive waves. Not the other way around.
It's also the other way around. Leafs when shaken produce waves in return.
You observe leaves shaking when there is wind (a correlation). To test for causality you need to make an intervention. You still the leaves - the wind keeps going. You block the wind - the leaves stop shaking. There clearly is an asymmetry here. The physical equations may be symmetric, but this doesn't justify calling a microphone "speaker".
Re: If you watch closely enough, everything is a speaker
#45Everything is a microphone?
One could say these objects are both. They pick up sound, acting as microphones, and send it back out by vibrating, acting as speakers (amplifying it by a factor of less than one). The camera acts as the microphone for ‘hearing’ that sound. I think you could hear that produced sound with a traditional microphone, but you would probably call it the echo of the original sound, and it might be hard to hear it over the o…
It would be much more accurate to say these objects are neither speakers nor microphones. It is not a surprise that all objects vibrate in response to sound waves. What characterizes speakers or microphones is that they are transducers converting between acoustic signals and electrical signals. None of these objects are transducers so it's not accurate to call them speakers or microphones. It is reasonable to refer to the system of camera plus software plus observed object a kind of microphone but certainly not to refer to the observed objects as speakers or microphones.
An aeroplane flies through the air and a submarine travels through the ocean. I can throw a rock into the air or into the ocean, that doesn't make a rock an aeroplane or a submarine.
Re: If you watch closely enough, everything is a speaker
#46I once heared radio news coming out of my electric guitar, pretty scary.
When I was growing up, we would often hear radio stations faintly in our vehicle after we had parked it and shut it off on our driveway - that's how I learned that radio waves go through everything all the time. It wasn't just one time or one vehicle, it happened in quite a few spots on our driveway.
Re: If you watch closely enough, everything is a speaker
#47Earlier quoted context omitted.
It's also the other way around. Leafs when shaken produce waves in return.
You observe leaves shaking when there is wind (a correlation). To test for causality you need to make an intervention. You still the leaves - the wind keeps going. You block the wind - the leaves stop shaking. There clearly is an asymmetry here. The physical equations may be symmetric, but this doesn't justify calling a microphone "speaker".
>The physical equations may be symmetric, but this doesn't justify calling a microphone "speaker".
Actually a speaker is just a microphone with very small adaptations depending on the use (polarity, noise sensitivity, etc).
But this is not about the wind, but about sound. The wind you describe is external ("You still the leaves - the wind keeps going"). But you can just as well have a wind produced by the leafs themselves.
Re: If you watch closely enough, everything is a speaker
#48Impeached Arizona governor Evan Mecham (shortened term 1987-1988) was probably very paranoid during his time in office, but nobody gave credence to his concern over the possibility of "reflected laser use" to surveil him. From Wikipedia ( https://en.wikipedia.org/wiki/Evan_Mecham ) ... Throughout his administration, Mecham expressed concern about possible eavesdropping on his private communications. A senior member o…
No one took him seriously because "I always have a radio on. It keeps the lasers out." is a textbook example of the kind of thing someone experiencing paranoid psychosis will say.
i.e. there are certainly listening devices that operate based on bouncing a laser off of a window[1] (or some other object), but his use of a quasi-magical protective measure (radios allegedly protecting against lasers) - in addition to the other behaviour mentioned - strongly implies that he was in need of psychiatric care, as opposed to being under surveillance.
FWIW, I've met multiple people with paranoid psychoses of one sort or another, and all of them have incorporated elements of real-world technology into their delusions.
[1] e.g. http://www.lucidscience.com/pro-laser%20spy%20device-1.aspx
Re: If you watch closely enough, everything is a speaker
#49Silly question: isn't this phenomenon bound by the Nyquist limit, which means it would take at the very least 4k fps to reconstruct music (considering that a soprano can get no higher than 2 kHz)? That sounds like an impossibly high framerate.
4K fps? Impossibly high? Not at all. There are consumer compact cameras and even smartphone sensors that can hit 1K fps [1] -- and those are not even specialist high speed cameras. Specialist cameras hit 4k fps at second gear, and can go as high as million fps (and even trillion fps [2])! Besides, this is about reproducing music frequencies, whereas the most probable target for this technology is eavesdropping, not a…
wait, 4.4 trillion fps with a resolution of 450 x 450 ? Isn't it petabytes of data per second?
Re: If you watch closely enough, everything is a speaker
#50I see everything as an antenna.