March 1, 2008

Defeat infrared surveillance cameras

A German arts group is publicizing a technique to defeat surveillance cameras that can see in the infrared range by overwhelming their arrays with infrared light from IR LEDs mounted on a headband or hat.

According to commenters, this technique would work best against low-light surveillance cameras with particular sensitivity in the infrared range, optimized for low-light situations.

Many cameras have sensitivity into the IR but wouldn't be so easily overwhelmed by the brighter infrared LEDs.

Security Insider claims this technique would only work intermittently against cheap CCTV cameras:
I can tell you that this may work for a second or two on cameras that have a cut filter (that's the real name for "IR sensitive" cameras), but all that is really going to happen is your face will get illuminated in between the frames that are actually "flared" out by the light. Also, you're more likely to be noticed doing this due to the motion detection alarms going off due to the large pixel change. You would be much better off with a laser, than an LED. We've been doing these type of tricks for years in the lab to try to trick the cameras. Anymore, its not the cameras you need to trick, but the intelligent video algorithms that are going to pick up on the anomaly and register it as an event. Oh, one more thing. Don't even try to attempt this during the daytime. Like another poster said, the cut filter doesn't activate until a timer either trips it (set on a schedule) or a preset low lux threshhold is met. (it gets dark). Even then many cameras these days have dynamic range circuits that will tame the bright spots and highlight the dark spots. Look up some Pelco, Panasonic, or Sony cctv specs for more info.

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