3D Vision, Magic Eye, and Jell-O

Published 2023-09-30
How on earth do those Magic Eye illusions work? In this video, we'll learn how humans see in 3D to get to the bottom of it. We'll learn about methods of depth perception, an algorithm for making autostereograms, and a physical model of binocular vision.

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Intro: 0:00
Depth perception: 2:02
DIY autostereogram: 5:34
Jell-O model of vision: 8:44

Thank you to Caleb Birtwistle for captioning!

Magic Eye: www.magiceye.com/
Bird motion parallax: wexler.free.fr/library/files/kral%20(2003)%20behav…
Chameleons: link.springer.com/article/10.1007/s003590050182
Random Dot Stereogram: archive.org/details/bstj39-5-1125/mode/2up
Autostereogram algorithm: link.springer.com/article/10.3758/BF03202884
Best book: Bela Julesz, Foundations of Cyclopeon Vision

All Comments (21)
  • @InvaderMik
    For the longest time, I believed that those autostereogram books in schools were an elaborate prank my classmates were pulling on me. They’d pretend to see an image where none exists. Now I see how committed to the bit they are! They wrote an entire book, published multiple papers, and created this entire video on the science of this thing that I still can’t observe!
  • @thesoupin8or673
    This was incredibly worth it even just for the image of a chameleon with glasses on. Delightful
  • @ShumaBot
    I'm one of those people that can go cross eyed on demand and could always see the picture in magic eye pictures. What I never realized until it was shown here was that you can use the same method to instantly see every single difference in "spot the difference" puzzles. I tried it and it genuinely feels like a newly unlocked (if not particularly useful) superpower.
  • @fuzzyeuka7897
    You'd need to do multiple jello pours to get the magnets to sit at the right depth. Base layer, then magnet layer.
  • I am convinced that I am physically incapable of viewing these magic picture images. Which, considering I have myopia, astigmatism, and a lazy eye, is probably true, lol.
  • @yari_dawg
    that brain is way too wrinkly to be mine
  • @HedgehogGolf
    I love that the background is an autostereogram of your bird logo lol
  • @Flopsaurus
    Representing what they eyes see as a bunch of tiny magnets together takes some serious abstract thinking
  • @tehweez
    Grew up blind in one eye so never got to see the magic images. A friend of mine gave me one of these books as a birthday gift on my 19th birthday knowing full well I couldn't see the pictures. We had a really really good laugh about it, and it's still one of the most thoughtful gifts I've ever gotten.
  • @Leadvest
    I think the important part of the oscillator array example is that the fields don't need to be overlapping for the phase shifts to be discernable. Sort of like how the rhythmic activation of neurons can communicate phase shift fields as signals without the ganglia physically overlapping.
  • @xdarin_
    Finally, a use for my ability to cross-eye on command
  • @spacelem
    I find wall-eyed stereograms much harder than cross eye-ed stereograms, mostly because it's much easier to move the two images further. The image at 7:00 is (I think) wall-eyed, but the two pictures are so big and far apart that I cannot get my eyes to point that far apart. The best I can do is go cross-eyed and get an inverted image (I could edit the image to swap them round, but my GIMP skills aren't the best).
  • @MrL314
    I have never been able to visualize these before, and this video is the first time I’ve ever been able to truly make the effect happen! My mind was absolutely blown seeing it really happen for the first time ever
  • @rojnx9
    It was a very nice touch that you hid your logo as a stereogram in the background, and you didn't even mention it.
  • @smoceany9478
    im sorry for watching this im not a bird i just like the videos
  • @zimbu_
    That's an excellent excuse to give chameleons tiny, wonky glasses. Kudos to the scientists on that one.
  • @theBATgoesUPoh
    this really feels like unlocking a superpower. my only exposure to autostereograms before this were when i knew what the image was supposed to be, so i was able to just kind of let it happen. i knew i was capable of seeing the image, but i didn't know how. after watching this video, i can control it now
  • my grandparents had one of those magik eye books floating around for when grandkids would come over. i was the only one who ever figured it out that you just cross your eyes and it felt so simple to me but everyone else in my family thought my explanation was nonsense and the book was a scam
  • @Draconis_Eltanin
    Wait, you're telling me they should pop out of the screen/page and not be carved in? Have I always looked at them wrong?
  • @El-Burrito
    I don't know if it's the same thing, but my favourite thing to do is play spot the difference, where you can put two almost identical pictures next to each other and then go cross eyed until they overlap and your brain gets used to it. It's then easy to look around at the image until it gets blurry, at which point you've spotted a difference. It's super cool cause you can use the same trick to look at two images that are slightly offset and it'll give a 3D effect, much in the same way this does. Edit: And I proved I left my comment before finishing the video since you do end up mentioning that