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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.
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.
I think it would still be possible to deanonymize that path data. If you make a credit card purchase, the information about time and place of the credit transaction can be associated with whatever id you use hashed or not. The path data has information that someone was standing at the cash register at that time and place. With the credit card information (or even just loyalty card information) you know who it was and can associate that with the entire path through the mall. Similarly, if they walk past a Starbucks and their smartphone associates with their WIFI, now if you have access to Starbuck's information you can deanonymize it from that. Or it could be deanonymized with the security cameras.
I don't see then how it could be subpoena-proof if you store the actual path, regardless of however you anonymize it. They can subpoena your data together with other data to get what they want.