Communicating Billboards: Signs That Can See

Imagine watching an advertisement that is watching you. Sound creepy? Some billboards can already communicate by text or photo message with passersby, and researchers are now endowing these signs with artificial intelligence that can take cues from viewers' behavior. Scientists at National Information and Communications Technology Australia, a government-funded research lab, have developed a billboard technology that watches body language and can tell when you're bored and when you're paying attention. The idea is to entice people who are well placed to make impulse purchasing decisions—pedestrians in shopping malls, in department stores, at airports or on sidewalks.

This is the future of "agile retail" technology, one of the fastest-growing areas of advertising. It includes digital billboards that can be easily changed throughout the day, allowing commuters to see ads for breakfast cereals in the morning and television shows in the afternoon. Advanced versions can deliver added information about the product. Here's how the next generation will work.

The system consists of an LCD screen playing a promotional video, and a camera to monitor people who come within five meters of the screen. In less than half a second, the software can determine if a face is turned toward the screen or away from it. If the viewer shows interest and does not walk away instantly, the system extends the video's playing time. But if the viewer begins to turn away, the sign switches to a video advertising a different product in the hope of grabbing back the viewer's attention. If the viewer gets bored with a credit-card advertisement, he might get a promotion of a family-dinner deal at a restaurant nearby. The researchers are working on a future version of the system that can distinguish between adults and children, using facial expressions and height measurements.

One of the advantages of having a camera trained on the potential consumer is that it could give advertisers feedback. Video-recognition software detects which angle a customer's face is turned to and determines what part of the screen he's looking at, which would tell advertisers which parts of an advertisement work and which don't.

It's too early to tell whether NICTA's approach will work. Customers may have concerns about privacy, or the ads may be too intrusive. Advertisers will be closely watching the technology that watches you.