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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.
I suppose this could be used to record an entire game and then go back and track what each player was saying during the game based on their positions on the court. I'd be interested to see if this could be used in a football stadium (domed or not) with all the extra noise and people.
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.
- For the complete works of Shakespeare: cat
...is it 315 or 325? Sheesh.
Fancy slashdot web2.0 math tells us there is no difference between those numbers.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
Surely that would be better written as "terrifying" rather than "impressive"
Score:-1, Funny
The Conversation
I once took an excursion to Reddit, and later HN. Unlimited up/down voting sucks when dealing with a hive-mind.
Now they can enforce the no cell phone usage while driving! Even those pesky key presses won't be able to hide!
Wow... why limit it to just stadiums? You could have arrays of these things lining every street and every mall! Just imagine how many terrorists you could catch by processing all the millions/billions of conversations going on in public places. All that data would be handy for collecting evidence against criminals too, you just go back through your chatlogs (all indexed per-person with voice/facial recognition) and dig up every conversation they've ever had outside.
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.
This sounds like beamforming. Submarines do this. Works great.
What are you doing on this website? This is no place for the likes of you.
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
Just make a disc fifty feet wide, using optimal golomb ruler placed microphones in a full hemispherical phased array of around 10,000 microphones, hang it from a tethered helium balloon, and now you can pick out any conversation in an entire city-sized area.
Nope, nothing to be afraid of here...
Life, the Universe, and Everything... in my image.
The 70's called... they want their beamforming back
The classic Coppola movie, The Conversation.
you had me at #!
This is a cool application of a well used technique. http://en.wikipedia.org/wiki/Phased_array
MyFirstNameIsPaul beat me to it. Innocent error...
you had me at #!
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.
It must have been something you assimilated. . . .
...will be most pleased that this is now possible.
... add this recorded decoded demultiplexed sounds to the street view. Would be cool. Or Evil.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
... 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.
a 4-mic tetrahedral array can do the same thing.
Set your phasers on "funky"!
Just in case anybody is confused, that is cool as shit. That's all.
..description. But it sounds like it is in their business plan.
excitingthingstodo.blogspot.com
I hope this can be applied to people like me, who have difficulty picking out the voice of the person you're talking to when there's lots of background noise.
Maybe that's why I don't much like big crowds or loud parties. Best party I was at had lots of deaf people and others who knew sign language (including myself), so even if you were on opposite ends of the room, you could still carry on a conversation, despite the booming loud music.
- RG>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
> 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.
Well, why would anyone alive during the cold war get terrified about thousands of nukes that would effectively destroy the world? The thing is technically impressive; whether or not it "terrifies" a certain person is about perspective and that person's tendency toward becoming terrified by mundane objects.
--
Ah, the dreaded comma splice.
-- IANAL, this isn't legal advice, and definitely isn't legal advice for you. Also, Squee!
So I guess your local terrorist cells won't be having their strategy meetings under the cover of all that stadium noise any more. Of course it also means that Randy Dandy might wanna think twice before sitting in the stands with his best bud and confessing that he's been cheating on his wife.
He'd kill us if he had the chance.
--- The American Way of Life is not a birthright. Hell, it's not even sustainable.
No more lip-reading for HAL!
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!
Set your phasers on "funky"!
This could be a boon for speech recognition systems, especially for use in areas with lots of environmental noise, or even just a little.
Maybe even the effort in clearing out the environmental noise will lead to the ability to clean out the "noise" (accents, minor physical fluctuations) from a person's speech- perhaps to such a point that the complexity of the software speech recognition problem is reduced.
/.'s 10 Millionth
Deployed at public gatherings, the super-mics could be zoomed in to eavesdrop on conversations between suspicious persons, or pretty much anyone the cops want to listen in on. Are you scared yet?
Are you afraid yet? Better not say something listening politicians don't like.
Falcon
Should there be a Law?
I'd be interested to see if this could be used in a football stadium (domed or not) with all the extra noise and people.
The sound in a basketball stadium can be just as loud as in a football stadium.
Falcon
Should there be a Law?
525
Sewage Treatment Facilities - "Our duty is clear."
"obtusery" is not a word.
True but use of these will spread, and may be used in public spaces too. And while there is no privacy in public spaces, courts have ruled that at least, it can still stifle political speech.
Falcon
Should there be a Law?
this was done by under grads from umass 6 yrs ago. I have no Idea if this was the first time it was done, but big deal
http://www.ecs.umass.edu/ece/sdp/sdp04/goeckel/
tach315
It was a room set up with microphones around the periphery,
set up to be a dynamic mobile microphone. When turned on,
it captured the loudest talker in the room, and amplified it
for the rest of the room (also automatically canceling out
feedback).
[BTL == Bell Telephone Labs]
How they always introduce these technologies as fun, as if they're only made for football games and boxing matches.
Expect to see these at any large political rally, big people's gathering, or any other public event where those darn ever-so-elusive terrorrists are hiding. Just make sure you don't make your thoughts known to people in the crowd, lest you end up on the no-fly-list because you support the wrong candidate.
The magical number is: 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
Except with 8 mics mounted on a mobile robot. The bottom line is that the more microphones you have, the easier it is. Another approach is to use a big parabolic "antenna" put a mic at the focal point, and steer it in the direction you want to listen. Of course, the advantage of the mic array is that you don't need any motor and you can actually listen to more than one source at a time.
Opus: the Swiss army knife of audio codec
Put a large number of small speakers in the roof, find out where you want to project your message, and delay-and-phase the audio just right so that it is heard at that spot, and only that spot.
He'd kill us if he had the chance.
There, FTFY.
youranonymityisanillusion.
I do some community theater work as a hobby - amateur stuff - and wonder if something like this could be used to track multiple actors on stage? Might be better than fitting them all with transmitters and lavaliers. Targeting would become the next problem, I guess.
Spoiler. ;)
--- The American Way of Life is not a birthright. Hell, it's not even sustainable.