Staring at a billboard while stuck in traffic? Well there's a good chance one day soon that billboard will be staring back at you. Quartz reports advertising company M&C Saatchi was testing out what it calls "the world's first-ever artificially intelligent poster campaign" in London over the summer.

Basically, the company created digital billboards with cameras attached to monitor the faces of passersby, according to CityMetric. The billboards—for fake coffee company Bahio—change images, slogans, and more based on whether viewers appear happy or sad.

It can monitor up to 12 people at a time. “It’s the first time a poster has been let loose to entirely write itself based on what works," M&C Saatchi executive Dave Cox tells the Guardian. But human copywriters won't be out of a job just yet, the Guardian reports. “It’s not writing the best ad in the world," says Cox, whose creation was using the nonsense slogan "Bahio is the new steam" for a while.

"There’s a lot of weird copy." Think artificially intelligent ads sound creepy? Let Cox reassure you. "We're trying not to be creepy," he tells Quartz. CityMetric agrees the new billboards—whose creators say won't store images—aren't an invasion of privacy, at least not nearly as much as current web ads based on browsing and social media histories.

However, the publication says there will come a day soon when ads are using our heart rates, life histories, politics, breathing, and more to sell us stuff.

(Copywriters aren't the only ones who need worry: Robots could also make lawyers obsolete.)

This article originally appeared on Newser: New Artificially Intelligent Ads Are Reading Your Emotions

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