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Surveillance Cameras Get Smarter
kog777 writes to mention that the IB Times is taking a look at where surveillance camera technology is headed. Soon researchers tell us that cameras will be available that not only record, but are able to interpret what they see. "The advancements have already been put to work. For example, cameras in Chicago and Washington can detect gunshots and alert police. Baltimore installed cameras that can play a recorded message and snap pictures of graffiti sprayers or illegal dumpers. In the commercial market, the gaming industry uses camera systems that can detect facial features, according to Bordes. Casinos use their vast banks of security cameras to hunt cheating gamblers who have been flagged before."
Have you ever actually heard a gunshot? As in live, in person? I have. Gunshots are very loud. Much louder than a mobile phone speaker. Mobile phones simply do not have the dB range to mimick a gunshot accurately.
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I'd think "switch view to camera that detects movement" would be a good-enough feature for most places. That would at least alert a live operator to a view where something MIGHT be going on.
Most sound effects / recordings of gunshots aren't accurate representations of the sound (aka, air pressure waves) produced when a gun actually goes off. They're more of an artists' interpretation of what the human mind thinks that a gun sounds like, based on what we remember them sounding like after we've heard one.
Most speakers can't accurately reproduce a gunshot, because they can't move enough air at one time to create the pressure wave. They play something that's more of a "boom," when in reality a gunshot is a sharp "crack" (followed by reverberations / reflections from the room or surrounding objects). Not being able to play the initial 'crack' very well, they over-emphasize the reverberations.
A 'gunshot sensor' would probably be a microphone or microphone-like device that was purposely de-sensitized so that it only received particularly loud, sharp sounds. You might be able to fool it with something explosive (like dry ice and water in a soda bottle), or where there was a significant release of pressure (car backfire), but most sound-reproduction systems wouldn't cut it -- they don't move that much air at once. Even with things like backfiring and explosions, you could probably filter them out if you wanted to, because I doubt they're the same when you really look at the waveforms (I suspect that the high pressure escaping from the small aperture of a gun's muzzle makes a very distinct sound from a car backfiring through the 1-2" muffler), even though they sound the same to a person, because we're not good at discriminating very loud, sharp sounds.
OT: I wonder what a nearby lightning strike "sounds" like to a microphone with the capacity to accurately measure the maximum amplitude of the sound?
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
I know I asked the question but I'd like to post my, umm, hopes for how this will turn out.
1. Standards of Law will have to change. As it is now, if people were recorded 24x7, and held accountable for everything done, everyone would be in jail and or have racked up millions of dollars in fines. So what would this do? It would have to make laws that are much more relaxed, lenient and reflect actual intent of evil or harm.
2. punishment would have to be adjusted to actually reflect the crime. Would this also be able to change things like drinking and driving laws? Right now they are so out of control, if you have been drinking and the cops go to pull you over you have about equal consequence if you are to pull over and cooperate as you do if you flee from the police, and are picked up much later after the alcohol has left your system, but if your recorded history shows that you don't drive any worse after having a beer at the pub, but after 3 your driving habits change would this make the legal limits individualized and appropriate rather than blacked and abusive as they are now?
3. In a fully monitored society, what would be the justification for things like anti-gun laws? If Big Brother always knew what you were doing and could see that you grabbed your rifle and are now climbing the clock tower and stop you before you could do anything, how could they say that you can't own any gun you want? If I enjoy taking a fully automatic machine gun to the range and blasting off some rounds, big brother nows I like doing this and watches me ever time and tracks to see if I deviate in an attempt to go shoot up a school and stop me before that could happen. Fully monitored societies could actually be more free.
Paying taxes to buy civilization is like paying a hooker to buy love.
You're probably right that a cellphone wouldn't be able to do it but building a decent facsimile thats easy to hide wouldn't be hard. You'd probably get arrested though for defrauding police. You'd have to be more innovative, maybe incorporate your sounds into a song then play it over a boom box and say that you were just listening to music.
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I doubt you have ever shot a .45 before, or been near one when one is fired. The .22 I'll give you - not that loud, could easily be mistaken for a backfire or fireworks. I can guarantee you a .45 would not be mistaken for a car backfiring - even with ear protection it still is quite a bang. Without earplugs, even being on the range when .45s are being fired will cause you to cover your ears instinctively. I have shot thousands of rounds from 4 or so different models of .45s, and not a single one of them could even laughingly be called "semi-quiet". 9mms are not as loud either, but usually they are so rapid in succession that you know it isn't anything but gunfire. See, living in the city CAN teach you things!
It would be very hard to realisticly duplicate the decibel level of actual gunfire on a boombox. The sounds you could get, but not the volume. And IANAL, but as far as I can tell, playing sounds of gunfire isn't illegal (unless done with intent to commit some other crime perhaps), but discharging a firearm is. If playing gunfire sounds was illegal, gangster rap would have been over shortly after it started in the 80s.
"But this one goes to 11!"
yes, grandparent poster can look it up, a .45 or 9mm is 155+ db, a 357 magnum 160+ db, even the lowly .38 special 153. No car stereo or boom box ever made sounds like that, you'd go painfully deaf if that level of sound lasted even a second.
I find the 9mm higher pitched but not quieter than .45 ACP. Even lowly .38 special out of my snub nosed Ruger SP101 has a roar under the high pitched crack that no one is ever going to mistake for a firecracker.
- More On Gunshot Detection
- Don't Fire A Gun In Minneapolis, They're Listening
Follow the links in those posts for more information.Perfect is the enemy of done.