On "Which Face Is Real?", you'll be presented with a photograph of a real human being and a computer-generated face. Can you guess which one is real? I made 8 correct guesses out of 10 and based my guesses on the realisticness of the people's eyes. The look in the eyes of the computer generated image usually feels a bit uncanny looking to me, and I'm able to tell the difference between the real and fake image this way.
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"Which Face Is Real has been developed by Jevin West and Carl Bergstrom at the University of Washington as part of the Calling Bullshit project. All images are either computer-generated from thispersondoesnotexist.com using the StyleGAN software, or real photographs from the FFHQ dataset of Creative Commons and public domain images. License rights notwithstanding, we will gladly respect any requests to remove specific images; please send the URL of the results pages showing the image in question."