Adventures in Stereograms | Hacker News Reader

Adventures in Stereograms

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I saw Magic Eye in elementary school and loved them.

I got into making them, but didn't have the actual software, so I used MS Paint. I would take an image and copy and paste it across the screen. Then take a rectangle and shift it over a little bit to make it pop in 3d. Then use the skew tool to make it angled in 3d. Most of them were pretty crap, but the technique worked well for one I made with butterflys. The background was all an image of repeating butterflys, but then some popped out, and their wings perfectly angled in 3d by MS Paint. I'll try to find those old images.

I must have been like 10, I was on a Yahoo message board with the referenced 3Dimka and other stereogram makers. I posted some horrible images and they were like "who is this kid". Haha.

My stereogram obsession faded, but I figured out you could take 3d photos by taking two photos side by side. Then view them in the same way you view a stereogram.

Fast forward a few years, and it's pretty cool to see everything with VR. I still don't have a headset, but it'll be cool to go back through my old photos and see them in 3d. Anyone know anything about the VR stereophoto community?

Found some old emails from that yahoo group:

>Nicely done, Wojtek! >If only I could generate depthmaps for stereophotographs.... >3Dimka ;)

After being obsessed with stereograms in middle school, in a crazy coincidence, in college I had the opportunity to work on some computer vision research doing exactly this, computing depthmaps from stereophotographs. https://vision.middlebury.edu/stereo/data/

> We do not provide any implementations of state-of-the-art stereo algorithms

Aww, I had my hopes up.

This was the first time I had seen this kind of thing as video. I was locked into it for a long ways through the video until I blinked and then lost it. I wasn't able to get back the 3D image. However, I did suddenly become aware that if someone was to walk past me staring deeply into the static, that they might have some concerns for my well being.

Edit: I am impressed that the lossy compression did not destroy the pattern. High frequency patterns like that tend to not compress well. Even more impressed since it was a YouTube compression. Would hate to see it if it was one of the lower quality HLS streams.

Stereograms never really worked for me, but this seems like a good place to share a related story.

Tool released an album with a bunch of stereo optic album art back in 2005 or so, with built-in glasses to go with them. I was home, sick, with time to spare, and tried to make these work. People online said they could see the images in 3D immediately, but it would take me 5-10 minutes of staring to make each page pop with depth. After I put the album down, I looked around, and - holy shit - the room around me was in 3D, like the stereo optic photos and art.

The effect faded after a few minutes. That's when it occurred to me that I'm some kind of stereoblind. I have depth perception, but it's almost like my brain uses an inefficient algorithm. The only time I naturally see depth that pops like that is when I'm looking out at vast, vast spaces - driving around the American southwest, for example.

I'm the only one in my immediate family who doesn't need glasses. My vision is sharp, it's good at night, and I often joked about how the 80s/90s idea that TV ruins your eye sight was a myth.

I think the joke is on me. Because I didn't spend enough time focusing on far away things, I never learned to relax my eyes that way, and Magic Eye never really worked for me. I like to think that explains why I sucked at sportsball (although did okay with soccer)

Back to when that Tool album came out - weeks later, I heard a story on NPR about a doctor who was challenging the accepted theory that if you don't develop depth perception by age 8, the synaptic paths are set, and you can never develop depth perception. By setting up a string, with beads placed a couple of inches apart, attach it to the wall, and then every morning, and stare at each bead... And people were able to learn depth perception!

I didn't ever set that up. Sometimes, through an old mirror, I can see depth. It's wild. But, for no good reason, I can't be bothered to practice on a string of beads, or whatever.

Don't spend too much time in front of screens, boys and girls. Go outside and play.

The album is 10,000 Days, by the way.

Various eye conditions can cause binocular vision issues. People can be unaware of a mild condition. They can have 20/20 vision. Have you taken any binocular vision tests? Eg https://en.m.wikipedia.org/wiki/Worth_4_dot_test

It’s why I can’t see stereograms. In normal vision my brain gives up. I only see through my left eye. The neurological strain of convergence is over a threshold and my brain decides to just use one eye. If I cover my left eye, then I see through my right eye. It’s particularly annoying as my left eye has worse vision, with two other later developed conditions.

A small grace is that I believe it improves my photography. People say I have a “good eye”. Ironic. You may have noticed people often squint, close an eye, or tilt their head when framing. This is to disturb depth perception and better predict a 2D rendering. It’s just how I see.

I’m also very clumsy. Maybe that’s why. It’s hard to evaluate causation.

Get your eyes tested for this …

It's been a very long time since I've done any vision tests, but I remember something like that, and I'd passed all my vision tests with flying colors - admittedly, that was over two decades ago.

I definitely process vision from both of my eyes, but it's kind of difficult to describe. It's almost like there's kind of an overlay between the two scenes outside of the focal point - but it's not nearly as distracting or disorienting as that sounds. I'm getting all the data, I'm just not assembling it correctly.

The small grace for me is that traditional 3D shooters never made me feel disoriented. However, when I tried Half Life 2 on an early Oculus Rift, I got simulation sickness pretty bad - felt nauseous for a good 45 minutes after playing for about 5 minutes :|

Having a really good ability of viewing them, I feel like it relies on two separate skills :

- Fine voluntary control of your eyes' accommodation

- Ability for whatever system is creating your depth perception to be more "flexible", in the sense that it can more easily "lock" onto a depth perspective as well as switching between them.

Thinking about it now, I'm not even sure how much voluntary control people normally have over their eyes' accommodation, if not exposed to experiences that forces them to practice it. I can definitely remember a time where I was not able to focus my eyes at will, which makes me think that it's not something the majority of people can do (granted it was when I was a child, so it might just be something you learn with age).

Yeah - I can cross my eyes on command because I clowned around as a kid. And I can actually get "Magic Eye" stuff to kind of work that way, it's just inverted... What I can't do is spread my eyes wider (I think the insensitive term is "go wall eyed") on command. I'm not cross-eyed at rest or anything like that, but the motor skills to widen the distance between my two pupils (The way you would when you're looking at something far away) just isn't well developed.

Hurts my head. I finally got the music video to work by trying to focus on my reflection in my laptop screen (so focusing past the screen). But twice I was distracted and suddenly "lost focus" and unable to restore the stereo effect.

I took a stab at a stereo game for the Mac over three decades ago, ha ha. Hilariously reviewed here: https://youtu.be/uGheXtrOWrA

Thanks for that link. Needed a laugh and that worked.

Stereograms were always a sore point for me. I could never see them. I can't see any of the ones in the post. I couldn't see the ones in the newspaper or the magic eye books. I've tried every suggestion I came across, squadoosh.

Fascinating. As a teenager of the 80s I could never see them. 35 years later, and with (more) deteriorated vision, I wondered if I’d have a revelation. Still nothing. Strangely affirming. I feel 15 again.

The same "trick" to seeing stereograms will allow you to quickly find the differences in the "spot the difference between these two pictures" puzzles as long as you have the images side by side. When your focus causes the pictures to overlay, the differences jump out.

I've seen some spot-the-difference games mirror one of the scenes, presumably to prevent exactly this.

I fell in the Magic Eye rabbit hole when I was 6-7, and spent so much time on it that I can now make the images pop in ~2-3 seconds, even 20 years later. I could also stare at them for hours without significant fatigue, as once you find the correct alignment, your brain will "lock" into the new perspective and you can totally relax your eyes.

One side effect I've noticed is that I have a really hard time looking at/focusing on geometric repetitive patterns. I will have the same effect as with Stereograms, namely that if my focus on the object is not close to perfect, the double image I see will have a tendency to really easily "lock" into the next alignment, rendering depth perception close to useless (even tho it's kinda fun/trippy to look at).

This 1994 book is an excellent book length prequel to this blog post:

https://openlibrary.org/works/OL3493694W/Stereogram?edition=...

Takes you from initial experiments with like 20 black dots through to the then popular magic eye type, but also much better ones, kind of the early forerunners of some of the experiments here.

Along the way it takes in Salvador Dali and a bunch of other cool stuff.

Free preview on OpenLibrary with an account.

I haven’t looked at a stereogram since the Magic Eye books of the 1990s but it came back pretty easy ! Highly recommend the music video linked in the article and also the horse by 3Dimka is really cool.

This is how much this kid-of-the-80s loved 3D stuff like this: I used to spend hours drawing my own Anaglyph pictures and comics with red and green biros, and putting on shadow puppet shows with red and green backlights for my completely unamused little sister.

There was just something magical about a 3d image popping out of a flat surface.

>There was just something magical about a 3d image popping out of a flat surface.

Is that how you see it so that the object is coming out at you? The way my brain sees it is that the background retreats away from the screen plane so that the object is just at the same level as the screen. More like I could crawl into the world that just opened up through my screen vs catching something coming at me from out of the screen.

I always experienced them 'back-to-front' as well, and I believe it is what happens if your eyes are focusing on a point in front of the picture ('cross-eyed') instead of a point behind it.

With a lot of effort, I can see it the right way by putting the image very close to my face, and relaxing my eyes to focus on an imaginary point beyond the page/screen. Then I slowly back away so that the image fits more comfortably in my field of view. However, I still find it very hard to bring the image into sharp focus, and at any moment the illusion can suddenly disappear and I have to start again.

I have excellent vision but after trying to look at these stereograms for a few minutes I am suddenly having difficulty focusing on normal objects around me. Quite unnerving.

The first encounter with Stereograms I had was in the DOS days with this software: https://archive.org/details/stare-eo-workshop

This still works in DOS but there are much better alternatives now: https://github.com/exoscoriae/eXoDOS/files/5523691/STW.zip

I had the same kind of accidental introduction to depth illusions as a kid. The family station wagon had a patterned finish that was just repeated squares. On long trips my eyes would relax and suddenly the pattern jumped off the surface. Unfortunately it's not so easy any more, I have a hard time getting them to lock in now.

Same thing, with bathroom floor tiles, ceiling panels, etc...

I could make them raise and lower by increasing the 'step' from overlapping by one, to two, to three, etc.

Always thought these were cool. I see them pretty easily. Had an idea that you could project "Wake Up Now!" inside your car windshield. When you get drowsy and loose focus, perhaps you'd suddenly see that, wake up, and pull over.

As someone who lived through the fad, but never managed to see stereograms[0], this hurt my soul a bit. There's so much cool stuff I'll never be able to experience!

[0] well, once on a Pepsi can in the UK in the '90s.

I had fun at the age of probably 12 or 13 figuring out I could create these sorts of stereograms in GFA Basic on my Atari ST.

I could never see stereograms properly, but I have no trouble seeing them by crossing my eyes. Unfortunately for most stereograms this inverts the depth.

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