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Fujitsu Tech Can Track Heavily Blurred People In Security Videos
itwbennett writes Fujitsu has developed image-processing technology that can be used to track people in security camera footage, even when the images are heavily blurred to protect their privacy. The company says that detecting the movements of people in this way could be useful for retail design, reducing pedestrian congestion in crowded urban areas or improving evacuation routes for emergencies. An indoor test of the system was able to track the paths of 80 percent of test subjects, according to the company.
actually i worked for a company that provided path information (it's really really important) and privacy was absolutely key. they went to a lot of trouble in the design of the software so that, if they were ever compelled, even by a court order, to "identify individual X", they would LITERALLY be unable to comply and, to avoid contempt of court, would need to go to some technical lengths to explain why. they didn't use images (because they don't work) - instead they used GNURadio to do GSM passive decoding and signal-strength detection. and no, you *can't* track the person themselves, nor can you get their telephone number, nor can you decode their phone conversations, nor can you decode their SMS messages (not "and track 1000s of phones on affordable commodity off-the-shelf hardware at the same time"). they also track bluetooth and wifi, but again, the mac addresses are hashed (with salting) *before* being stored on disk. the reason for this kind of paranoia is really really simple: they ABSOLUTELY DO **NOT** wish to be involved in privacy and identification issues. it would destroy their reputation. so they made damn sure it simply could not happen, even if they were compelled by a court order.
anyway - first important thing: the definition of a "path" (and why it's critical). a "path" is, as the word suggests, the places that an individual goes to, and how they got there, how long it took, and how long and where they were stationary. key factors critical for shopping mall owners to be able to provide to their retailers: (1) how many unique shoppers went into *their* store (broken down by time and date is also helpful). (2) how long each unique shopper spent in their store. (3) also useful to know is where they went *before* going to another store. it's therefore necessary to weed out "passers-by", and duplicates (losing the path then picking it up as a *separate* person, repeatedly) is *especially* bad as it completely mucks up this all-important information that the retailers, it turns out, really really like to have once they know it's available.
think about it: this information is really, really important. in attracting retailers, without this equipment (or anything like it), the conversation is "come to our retail park, we have 6 million visitors a year". the retailer isn't interested in that. *with* the equipment (or anything like it), the conversation goes further, "and the unit we would like to interest you in gets 15,000 unique visitors per day if occupied by someone with your type of retail profile, especially because there's a macdonalds / starbucks within 100 / 50 metres and we know that that gets better numbers for you". *that's* powerful stuff, and it allows the shopping mall management to pick (and test, and research) interesting combinations of retailers that will make the whole mall a lively and attractive place to be, instead of being boring, half-empty of both retailers and customers (the other half being tired, stressed and exhausted), and doing a dis-service to everyone who bothers to go there.
so anyway i had to be up on the "competition" so to speak, because we frequently got questions coming in from clients being pitched the "visual tracking" technology.
first flaw in visual tracking technology: balloons, signs, pigeons, dogs, baby strollers - anything that moves in uncontrollable ways that is big enough to block people: you're hosed. pigeons etc. are fun because they randomly block out huge areas directly in front of the camera if they get close enough. even "other people" is enough to block "other people". even identifying "people" from children, babies, animals - this is hard enough as it is and requires enormous CPU resources... the number of people in some of these malls is *enormous* - tens to hundreds of thousands.
second flaw in visual tracking technology: it's intrusive. put a camera in a shopping mall and people automatically get edgy. it changes their "behaviour", which is precisely what you do not want. the last thing you want in