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High-Tech Microphone Picks Voices From a Crowd
JerryQ writes with news of an impressive audio detection system from a company called Squarehead that was demonstrated during a professional basketball game. According to Wired, "325 microphones sit in a carbon-fiber disk above the stadium, and a wide-angle camera looks down on the scene from the center of this disk. All the operator has to do is pinpoint a spot on the court or field using the screen, and the Audioscope works out how far that spot is from each of the mics, corrects for delay and then synchronizes the audio from all 315 of them. The result is a microphone that can pick out the pop of a bubblegum bubble in the middle of a basketball game..."
...is it 315 or 325? Sheesh.
...'tis easier to blame than to improve.
In fact, that's exactly what TFA says.
You do not have a moral or legal right to do absolutely anything you want.
The Conversation
I once took an excursion to Reddit, and later HN. Unlimited up/down voting sucks when dealing with a hive-mind.
It occurs to me that if you store all 325 audio streams with accurate time-codes and the relative positions of the microphones you would be able to do this at any time later on the stored sound as well. You could probably get away with much fewer than 325 microphones at some cost in quality.
Yes. And that's already part of the system.
I read the article. It went from 325 to 315 to 300. They may have gotten it down to a single mic had they kept writing.
Maybe I should've read it then.
But I, like most Slashdotters, am so quick that I can just glance at a poorly written summary and instantly understand all that needs to be known about the topic. It's really a wonderful time-saver being so damn smart I don't even need to know the facts.
- For the complete works of Shakespeare: cat
This sounds like beamforming. Submarines do this. Works great.
How come you get terrified by an array of microphones with an impressive spatial detection capability? The thing is technically impressive, whether or not it "terrifies" a certain person is about perspective, and that person's tendency towards becoming terrified by mundane objects.
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
This system might also be hackable, such that people can preserve their privacy and not be listened in on from hundreds of feet away.
You simply have a microphone near your mouth, sample it, and repeat the sound out of a speaker with slight echoes with randomised delays. There must be something that could interfere with the process they use to "zoom in" on a particular sound source. Maybe if you can measure the distance to the listening device, it would be possible to manipulate the frequency of sounds you are making so as to create a standing wave or something that would cause the microphones to be overloaded or to hear nothing..... shit, maybe the tech that drives noise cancelling headphones could be used here? Who you are speaking to gets an earpiece with unedited sound piped to them, and speakers on your lapels kick out anti-sound so eavesdroppers hear nothing.
So now in public, you just need to have strings of randomised flashing IR LEDs illuminating your face, so CCTV has a hard time capturing your image, and now something to mess with your voice so that The Man cannot listen in too! If you are thinking "paranoid fucker", I am thinking what the fuck business is it of people to listen in on me? And that's a rhetorical question: I don't need to be told to think of the children, etc..
Car analogies break down.
"The thing is technically impressive, whether or not it "terrifies" a certain person is about perspective, and that person's tendency towards becoming terrified by mundane objects."
It is not the object that is terrifying, but rather what the existence of the object, plus the current trends in behavior by our Fearless(fearful) Leaders, plus a modicum of ability to put 2 and 2 together, yielding these devices being everywhere, able to monitor all conversations in the world.
www.eFax.com are spammers
This is a cool application of a well used technique. http://en.wikipedia.org/wiki/Phased_array
Just like Congress!
And, to be back on topic, referees.
Check out my sci-fi/humor trilogy at PatriotsBooks.
My father, would tell me stories when I was growing up about helping design a surveillance tool for ease-dropping on restaurant conversions that used the same principle. They had a map of the table layouts and you would place a pointer over the table you wanted to listen to. Mics hidden around the edge of the restaurant would capture the sound. This was back during the early 60's so they used a mechanical delay mechanism. Said it worked as well as if you had planted the mic at the table, plus you didn't have to worry about where they sat. Like many things, this is more powerful and versatile but hardly anything new.
... to a political rally near you. You probably don't need particularly accurate microphone placement and, in fact, if you had precise position and velocity coordinates of each of the mikes at any given time, they could even be moving.
That is all.
Just in case anybody is confused, that is cool as shit. That's all.
Meme-mongers: Imagine a Beowulf cluster of that array! Meta-commentators: (Present company excluded, well not really) Timothy! MAFIAACS: Oh great, they just copyrighted my gum-popping sounds. Insightful curmudgeons: Given sufficient sensitivity, this could be done with a tetrahedral array--50 years. Now, get off my lawn!
Yeah, but does it run Linux?
The higher the technology, the sharper that two-edged sword.