'Digital Camouflage' Shirt Confuses AI-Powered Surveillance Cameras

I am standing in front of a camera that’s streaming to a giant video screen. The image recognition AI running on the camera puts a big green box around me. “PERSON,” it says. Artist Simon Weckert hands me his newest creation, a button-down shirt with flowery, blurry globs of green and pink. I put the shirt in front of me. The box and the word “PERSON” disappears. I pull the shirt away. The box pops back up. I put the shirt in front of me. It disappears. This is “digital camouflage,” and it has confused the algorithm.

Weckert designed digital camouflage as a response to the proliferation of AI-powered surveillance cameras that detect people, vehicles, animals, bicycles, and other objects in their field of view. Many of these AI-powered cameras can detect when a person is lying down, “anomalous behavior” such as people loitering, people fighting, or an abandoned package, which can lead to a police response. These cameras are already relatively commonplace around the world, but Weckert created it because police recently deployed these types of cameras outside of Kotbusser Tor, a popular subway stop in Berlin. They are the first police-run object recognition surveillance cameras in the city.

“Obviously people don’t like it because it means that AI is tracking the movements and behaviors of people. It’s one thing to have somebody behind the camera watching you, but now we have AI doing this kind of analysis,” Weckert told me. “It can detect if somebody’s laying on the ground so that means homeless people could be detected and police get triggered.”

Weckert says one of the problems with Berlin’s cameras is that it’s not clear exactly which image recognition it’s running. But many image recognition cameras run a variation of YOLO (You Only Look Once), a family of open source image recognition algorithms. So Weckert installed YOLO on his own camera and began trying to confuse it by iterating on different types of random patterns.

He starts with a random pattern he said, and shows it to the YOLO algorithm to see if it detects a human, and with how much certainty. “When YOLO returns 100%, I know the pattern obviously isn’t working,” he said. “And then step-by-step, I change the pattern, I rotate certain parts of the pattern, change the colors, flip it so on and so forth. And every time we ask how much confidence do you have this is a person using something called gradient ascent to get away from the category of a person. And then suddenly you as a person, with the pattern on you, aren’t detected as a person because the algorithm can’t make sense of it.”

Weckert has done a series of buzzy projects before. Back at Motherboard, we covered the virtual traffic jam he created on Google Maps by sticking a bunch of GPS-enabled cell phones in a red wagon and walking slowly through the streets of Berlin. Digital camouflage sits alongside projects by other artists intended to hide people’s faces from facial recognition cameras or to confuse automated license plate reader cameras with shirts made of nonsense license plate graphics. Over the years, AI surveillance has improved to a point where many of these techniques don’t actually work anymore, but for the moment, digital camouflage does, at least on the very popular YOLO algorithms. Weckert said one of the major problems is that police won’t say specifically what algorithm they’re using, making it difficult to say whether his shirts work on the cameras at Kotbusser Tor.

“The problem is that we don’t know what technology is behind these camera systems, so therefore I cannot claim 100 percent that the t-shirt works against this specific camera system, but I can say I know it works for the very public and famous YOLO algorithm,” Weckert said. He said that just as fashion brands have seasonal updates, so too will his digital camouflage “Every time there’s a new YOLO, a new pattern will come out. Just like in fashion, the summer winter collection, here it’s the every YOLO edition.”

He said the project is not just intended to help people avoid surveillance, but to teach people about it and to show people there’s lots of ways to protest and push back against it. “It’s to give them the feeling that there are actually certain tools we can use against surveillance. It's not like we just have to accept what the lawmakers and police are doing.”