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The Daredevil Camera

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Re: The Daredevil Camera

#91

Post by shas3 »

wbeaty wrote: post #86

Very very cool! And it's about time someone did it! Yours is the first hobbyist project I've encountered since my own extremely crude ten-dollar version in 1981. No square array or processing, mine was a mechanical scanner-disk: eight LEDs glued in a spiral to an old vinyl record album, each with an electret microphone and and op amp. Spin the disk with a motor at about 6Hz. Wind noise, so add foam to the mics. It wo…

On the academic-industry/start up side, I know of one such device which does this on a sphere: http://visisonics.com/visisonics-audiovisual-camera/

It works quite well in my experience with it. The spherical geometry enables a 3D capture and visualization.

Re: The Daredevil Camera

#92

Post by acjohnson55 »

Brilliant project! I had a similar idea several years ago, when I was in a master's program in music technology at NYU. I had classes on acoustics and concert recording that really blew my mind as I started to understand how sound behaves within spaces. The idea of a soundfield camera occurred to me, and it seemed like it could potentially demystify a lot of phenomena sound workers have to deal with largely by intuition. Things like reverberation, acoustic modes, propagation patterns, wave effects, etc. I hope this project continues to mature!

Re: The Daredevil Camera

#93

Post by humbertomn »

Great post, Artlav! Great to hear from you after Exosphere in Chile last year. Eager for the next part of the project and hopefully you get some funds for your always interesting ideas.

Re: The Daredevil Camera

#94

Post by chris_va »

So impressive

If you get a x86 hooked up, doing some software cleanup might make the video look much better. Some ideas that you'll probably come up with on your anyway:

- Assign colors based on frequency clustering, rather than a heatmap (so, red=first freq, green=second freq, and so on).

- Persist colors if the frequency in a region shifts slowly enough (so every source stays mostly the same color).

- Remove echoes by finding correlated pixels.

Re: The Daredevil Camera

#95

Post by therein »

fudged71 wrote: post #85

Artlav, this is an incredible project! I have an idea for you. You mention that you want to use a webcam so that you can "overlay" this information on top of an image. What if you could send it directly to your brain? There is a technology called Brainport[0], which is effectively a 16x16 grid of electrodes small enough to place on your tongue. By feeding electrical impulses through these electrodes, you stimulate th…

BrainPort sounds extremely cool. How does the brain decide to interpret them as visual input, though?

Re: The Daredevil Camera

#97

Post by duaneb »

femto wrote: post #79
Artlav wrote: post #18

Earlier quoted context omitted.

Not exactly unheard of, but quite rare. I found a company that made large arrays like that, but they seem to operate in near field, measuring only the sound volume. Imagine a wall of microphones next to a truck - you can tell which part of the wheel makes the sound. That sort of stuff. As for an actual "camera" that turns sound into an image - i've never heard of one.

> As for an actual "camera" that turns sound into an image - i've never heard of one. I have. His name is Daniel Kish [1, 2]. Apparently his visual cortex has learned to process sound rather then light, so he literally sees, based on the sounds he is hearing. [1] http://www.abc.net.au/catalyst/stories/4441831.htm [2] https://en.wikipedia.org/wiki/Daniel_Kish

Unfortunately only he can appreciate his own experience.

Re: The Daredevil Camera

#98

Post by Animats »

Beam-forming microphones are well known. Here's a fancy ceiling-mounted one for video conferencing.[1] Here's the theory in Matlab.[2] And, most impressive is the surveillance version, the Squarehead Audioscope Acoustic Camera.[3] This, a 1m disk with 384 microphones, can pick out a single conversation in a noisy arena.

There's a version which records all the audio channels in real time, using a big disk array. This allows the phased-array processing to be done during playback, so the "aiming" can take place later. The company now has its catalog of surveillance products password-protected, but in the past, there's been more info about that application. The DEA has purchased two.

There are also "acoustic cameras" for locating noise sources.[4]

All this is a spinoff of submarine passive sonar technology from decades ago.

[1] https://www.youtube.com/watch?v=Bepqav87D40 [2] http://www.mathworks.com/help/phased/examples/acoustic-beamf... [3] https://www.youtube.com/watch?v=bgz7Cx-qSFw [4] http://www.acoustic-camera.com/

Re: The Daredevil Camera

#99

Post by femto »

duaneb wrote: post #97
femto wrote: post #79

Earlier quoted context omitted.

> As for an actual "camera" that turns sound into an image - i've never heard of one. I have. His name is Daniel Kish [1, 2]. Apparently his visual cortex has learned to process sound rather then light, so he literally sees, based on the sounds he is hearing. [1] http://www.abc.net.au/catalyst/stories/4441831.htm [2] https://en.wikipedia.org/wiki/Daniel_Kish

Unfortunately only he can appreciate his own experience.

He gives a pretty decent explanation of what he is seeing in the Catalyst transcript. It's fascinating, as from his description it's a low resolution (due to the longer wavelength) of what you or I would see. Presumably he also sees things such as colours, but based on audio reflectivity rather than optical reflectivity?

Your point about only him appreciating his own experience is interesting, as the same question can be asked of all of us [1]. In audio, maybe apples and oranges are the same colour and strawberries are different? It would be an interesting application of a sonic camera, to render the image so that equivalent audio colours are consistently mapped to the same light colours.

[1] https://www.quora.com/Visual-Perception-Is-everyones-experie...

Re: The Daredevil Camera

#100

Post by skrebbel »

A Dutch startup called Sorama has been selling this commercially for a while. It's very cool actually, they sell mostly to companies who want to make their hardware less noisy.

It turns out that noisy machines are often mostly noisy because a relatively small number of parts are too flexible, not screwed on tightly enough, and so on. Track that down and you know where your low-hanging fruit is. A daredevil cam is exactly what you need for tracking that down.

Their site is a tad unimpressive sadly, but their tech is very cool: http://www.sorama.eu

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