Shadow Analysis Could Spot Terrorists 245
Hugh Pickens writes "An engineer at Jet Propulsion Labs says it should be possible to identify people from the way they walk — a technique called gait analysis, whose power lies in the fact that a person's walking style is very hard to disguise. Adrian Stoica has written software that recognizes human movement in aerial and satellite video footage by isolating moving shadows and using data on the time of day and the camera angle to correct shadows that are elongated or foreshortened. In tests on footage shot from the sixth floor of a building, Stoica says his software was indeed able to extract useful gait data. Extending the idea to satellites could prove trickier, though. Space imaging expert Bhupendra Jasani at King's College London says geostationary satellites simply don't have the resolution to provide useful detail. 'I find it hard to believe they could apply this technique from space,' says Jasani." Comments on the article speculate on the maximum resolution possible from KH-11 and KH-12 spy satellites.
How exact is this? (Score:5, Interesting)
Will old people at the bus stop be killed by predator drones because their walk is 95% similar to OBL's?
I did some work on this a few years back (Score:5, Interesting)
My own was using lamberts cosine law to gather angular information on leg position by the light patterns reflected off the thigh of someone walking directly towards the camera.
The problem with gait recognition is, AFIAK, it's not really been proven to be a decent biometric - i.e. I'm not sure it's really all that unique, not without measuring things at a very high resolution, which probably isn't going to be possible either from space or with the current install-base of cctv cams.
Anyway, scary stuff if it does work.
Re:Upon deployment.... (Score:5, Interesting)
How does it account for any type of foot, ankle, or leg injury that doesn't require crutches?
How about someone throwing a handful of rocks in the shoe to forcibly change their gait?
How about someone that is conscientious enough to change their gait at every new location?
(I cannot lay claim to these ideas myself - I read Cory Doctrow's "Little Brother" - a very good novel that is licensed under the Creative Commons model and is available at http://craphound.com/littlebrother/ [craphound.com] )
This just reeks of wasted money and more governmental control.
Re:Geostationary? (Score:4, Interesting)
Still, this is clever idea. Attention conspiracy theorists: make sure to walk outside only at noontime. At the equator.
Re:Geostationary? (Score:5, Interesting)
5-10 cm is 1985 resolution, dude. About the time they got bought by Bournes (now Recon/Optical, Inc.), engineers from Chicago Aerial Industries were bragging at MIT meetings in Chicago that we'd never know the resolution of the Keyhole series. Recon, the successor to Chicago Aerial Industries now HQ'd in Virginia, has dominated the industry ever since CAI cameras detected Soviet missiles in Cuba in October, 1962.
And from the same sources, the original Hubble "mirror flaw" occured because they shipped a Keyhole part by mistake. Not hard to believe since they built both systems. Left unsaid was how similar the Hubble/Keyhole airframes were.
23 years later, after spending gadzillion bucks inventing & perfecting adaptive/active optics and instant digital signal processing we certainly are being observed even more closely.
Go ahead, ding a Senior Citizen for trolling... I'll soon be dead anyway.
Incorrect summary (Score:3, Interesting)
But the real issue is that to stop terrorism we have know before hand the people that pose a real and credible threat. And I am not talking about the people with video cameras who are going to prove the police force is lying in statements or beating people up. I am talking about knowing that Timothy McVeigh is going to kill almost 200 people, including children. Or that Eric Rudolf was going to mount a extended reign of terror killing a innocent woman and a police officer. How does the gait analysis going to save the babies that the next religious extremist is going to kill?
Re:Geostationary? (Score:4, Interesting)
Re:Solution in search of problem (Score:5, Interesting)
In Iraq, the US Air Force operates unmanned aerial vehicles to follow suspected insurgents. For instance, they will find a dude who just fired mortars and follow him around Iraq as he makes his getaway. He's unaware that he's being followed from the sky. Sometimes, he gets together with some other guys in a pickup truck with RPGs in the back. Then an Apache goes and blows that car up to hell. You can see videos like this at Liveleak.com. It's pretty fucking scary.
I definitely wouldn't use gait analysis alone to make a kill call, but I'd definitely send ground troops to a guy's house if I had enough confidence in the gait analysis.
Disguise your walk in advance, not during (Score:4, Interesting)
With homage to "The Usual Suspects," all the posters discussing ways to change their gait when committing a crime have it backwards. Start out from the first time your "identity" comes into existence with a limp, and after the crime is done, go back to walking normally. The gait marked with the criminal no longer exists.
Vegas... (Score:2, Interesting)
I met a guy that worked in security for Vegas a couple of years back. Back then he described to me how the security systems could identify you by the way you walk. Apparently those guys in Vegas are bit ahead of things in terms of security...
Autism=ticket to gitmo (Score:3, Interesting)
People with non-standard body language will suffer constant harassment from the police, and as such people often have psychological/neurological issues they will find it harder to defend themselves from aggressive questioning techniques.
The idea behind this is to filter people by 'normality' and assume that abnormality is evidence of criminality. Its a disgusting notion to me.