At 09:06 PM 10/31/97 -0600, Jim Choate wrote:

Forwarded message:

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TECHNOLOGY 'SECURES' GUNFIRE IN THE CITY

Secures October 31, 1997 Web posted at: 4:44 p.m. EST (2144 GMT)

ARLINGTON, Virginia (CNN) -- If you heard gunshots ring out in your neighborhood, you might be able to tell the general direction they came from. And if you happened to glance at your watch, you could say about what time. In maybe a minute, if you were so inclined, you could call the police to report it.

Now police have an electronic witness that can provide similar assistance: a device called SECURES that pinpoints the time and location of gunshots.

This would be a network of microphones and processing stations which could perform a reverse-GPS location analysis of sounds picked up by 3 or more microphones. (Sounds common to 2 microphones could be localized with a lower degree of accuracy if directional microphone arrays are used.) Yet another instance of Big Brother technology that is of limited value to the police. Of course, this means that you will have the police responding to every backfiring car, which will dampen their enthusiasm for responding unless full-auto fire or a prolonged gunfight is overheard. Of course, if you have a silenced weapon and some cherry bombs with cigarette time-delay fuses, you can use this system to docoy the police into the wrong neighborhood. Or if you confine yourself to single-shot assassinations near busy streets, it will probably be written off as a vehicle backfire, especially if you are doing a drive-by with a suppressed shotgun. (Not possible to silence completely, but certainly possible to quiet to the point that it wouldn't attract undue notice along a busy street.) In order for this system to be worth anything, it would have to be able to: 1. Use voice recognition techniques to classify the type of weapon (primarily useful for machine guns--it could evaluate the frequency characteristics, rate of fire, etc. to distinguish between an AK-47 and an UZI) sufficiently well to distinguish between small-arms fire, fireworks (cherry bombs, M-80's, etc) and vehicle backfires. 2. Perform "scream analysis" to distinguish the typical screams of children at play from those of gunshot victims. 3. Monitor conversations throughout the coverage area. A suspicious sound preceded by a male voice saying "Give me your money, bitch" would be much more interesting than one preceded by a revving engine. This would have the added benefits of allowing LEO's to track fugitives via the sound of their footsteps, their breathing, vehicle engine sounds, etc., as well as gathering voiceprint data from crimes in progress. I think point 3 is the scariest. A properly designed system could do voiceprint analysis of almost every word spoken in public, tie the conversations to the identities of the speakers, and archive the time, location, content and participants of every spoken conversation for long periods of time in a database that could be searched by keyword, speaker identity, time, and/or location. The following searches could be done: 1. "I want a list of everyone who uttered the words 'buy' and 'crack' in the same sentence between 2100 and 0330 hours within 500 feet of 123 Maple Drive between August 7 and December 5." 2. "I want a list of all participants in conversations with Citizen-Unit 754-35-9710 which included the phrase 'BATF agent' in the last 6 months. 3. "I want a map of Citizen-Unit 754-35-9710's movements for the last 2 weeks." 4. "I want to see the movement history of all '96 Ford Escorts with a misfire on cylinder #1." 5. "I want the identities of everyone involved in the assault that happened at the corner of Maple and Main at 1752 hours yesterday. The Big Brother potential of such a system should be obvious. What is really scary is that such a system could be built mostly with currently existing hardware, and at most a few man-years of software development. If each node in the network performs its own speech to text conversion and archiving, and coordinates with a central voiceprint ID server, (which could also provide the sync signal that the nodes would use to cross-reference between nodes to locate sounds) each node could consist of a Pentium 200 with some specialized audio signal processing cards and 15-20 GB of storage. The only really new thing required would be an .AVI-style format for storing MPEG audio, a text transcript of said audio (which would need to include keywords for gunshots, passing vehicles, and other events of interest), and location coordinates (updated on a second to second basis) which could be indexed for reasonably efficient searching. Jonathan Wienke PGP Key Fingerprints: 7484 2FB7 7588 ACD1 3A8F 778A 7407 2928 3312 6597 8258 9A9E D9FA 4878 C245 D245 EAA7 0DCC "If ye love wealth greater than liberty, the tranquility of servitude greater than the animating contest for freedom, go home from us in peace. We seek not your counsel, nor your arms. Crouch down and lick the hand that feeds you. May your chains set lightly upon you; and may posterity forget that ye were our countrymen." -- Samuel Adams "Stupidity is the one arena of of human achievement where most people fulfill their potential." -- Jonathan Wienke RSA export-o-matic: print pack"C*",split/\D+/,`echo "16iII*o\U@{$/=$z;[(pop,pop,unpack"H*",<> )]}\EsMsKsN0[lN*1lK[d2%Sa2/d0<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<J]dsJxp"|dc`

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Now police have an electronic witness that can provide similar assistance: a device called SECURES that pinpoints the time and location of gunshots.

This would be a network of microphones and processing stations which could perform a reverse-GPS location analysis of sounds picked up by 3 or more microphones. (Sounds common to 2 microphones could be localized with a lower degree of accuracy if directional microphone arrays are used.) Yet another instance of Big Brother technology that is of limited value to the police. Of course, this means that you will have the police responding to every backfiring car, which will dampen their enthusiasm for responding unless full-auto fire or a prolonged gunfight is overheard. Of course, if you have a silenced weapon and some cherry bombs with cigarette time-delay fuses, you can use this system to docoy the police into the wrong neighborhood. Or if you confine yourself to single-shot assassinations near busy streets, it will probably be written off as a vehicle backfire, especially if you are doing a drive-by with a suppressed shotgun. (Not possible to silence completely, but certainly possible to quiet to the point that it wouldn't attract undue notice along a busy street.)

In order for this system to be worth anything, it would have to be able to: 1. Use voice recognition techniques to classify the type of weapon (primarily useful for machine guns--it could evaluate the frequency characteristics, rate of fire, etc. to distinguish between an AK-47 and an UZI) sufficiently well to distinguish between small-arms fire, fireworks (cherry bombs, M-80's, etc) and vehicle backfires.

In late 1994 several members of the Wireless Communication Alliance, an organization related to Joint Venture Silicon Valley, gave a presentation on such a system for which they were seeking LE/government funding. As I recall the pilot was for East Palo Alto (for those of you not familiar, its a poor neighborhood, mostly minority, neighborhood between the Hwy 101 and the Bay). The wireless infrastructure was proposed to reduce costs to practical levels by providing an inexpensive link to more centralized processing. I haven't followed up and don't know if the project went anywhere. If reliable and used as presented it could reduce LE response to some violent crimes. The prospects for misuse are truly scary. --Steve