How do deepfake videos trick human perception?

Deepfake videos trick our eyes by making one person look like another, just like when a costume changes who you think someone is.

Imagine your friend Alex has a super cool robot that can copy their face and voice exactly, even when they're not there. That's what deepfakes are like. They use computer tricks to make it seem like someone else is speaking or moving, when really it’s just a clever copy.

Deepfake videos start with lots of pictures or videos of the person whose face you want to copy. The computer learns how their face moves, like how your mouth opens when you talk or your eyes blink.

Then, it puts that copied face onto another person's body in a new video. It’s like taking a photo of Alex and pasting it onto a picture of you, so it looks like you are talking, but really, it’s still Alex behind the scenes!

Our brains are amazing at figuring out what we see. But when something looks just right, like a real face moving naturally, our brain says, “That must be real!” It’s like trying to tell if a toy robot is pretending to be alive or actually is, sometimes it’s really hard to know the difference!