SEATTLE — Editor's note: the above video was originally created in 2017. 

Now you can test your ability to spot fakes online, and not just in the comments section.

University of Washington professors Jevin West and Carl Bergstrom have created a website that puts two pictures of people’s face side by side – one of them is real and one of them is fake.

The website, called WhichFaceisReal.com, is like a game in the way that is asks users to pick which face is real, but it is no laughing matter in the era of fake news.

West and Bergstrom already caught people’s attention with their college class that teaches student how to navigate through the mess of information online and on social media.

In the first two weeks that the website was live, there were about 4 million plays of the game and 70 percent of players chose correctly. The professors hope that the website will help people become better at spotting fakes. They might decided to make the game harder, too.

“We did not create the technology,” Bergstrom said in regard to the AI that can make fake photos, called StyleGan. “We wanted to get the word out that this is now possible. Generally up to this point, we have trusted faces in photos: If it’s a photo, it’s a real person — at least up to this point.”

Some of the hallmarks of a fake photo are inconsistencies in the background, glasses or earrings that don’t match, or so-called “water splotches” on the photo. The professors’ website explains that the water splotch is not actually caused by water but can appear when current AI algorithm produces a fake. 

Another way to tell if a person in a photo is fake is to try to find a second photo of that person but from a different perspective. AI can’t generate multiple photos of the same person, yet.

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