[Mendel]

Maybe I´ve been watching too many 3d movies or maybe there´s something weird about this picture, but it looks like it has some depth to it while obviously there is none.



It really looks like to me like the text bubble is far behind the character, the hair curls behind the head and the face seems to pop out.

I don´t usually see any depth in 2d pictures like this, not even in animations. So this one was a bit of a head scratcher. Just thought I´d share.

edit: tried taking a screenshot of it and the illusion is gone in a static image. So it is the movement playing tricks with my eyes.

[Dr Evil]

http://www.designboom.com/weblog/cat...e-project.html

There is few more for you. I'm surprised you haven't ran into these earlier.

[PixResearch]

They're pretty common and been around for a very long time.
http://en.wikipedia.org/wiki/Wiggle_stereoscopy

Essentially they just show a left and right eye view consecutively and let your brain sort out that it's getting the parallax info temporally through both eyes rather than through different eyes. You can do a very similar thing with panning/scrolling images.

If you pick the objects in the scene you want to focus on and have them not move between the images. Anything close or far away will have an increasingly large shift. Trying to capture the effect with a single image won't work as you can't see the shift.

[Grall]

It's creepy that the effect remains even when one eye is closed. Logically it's not surprising, since it's not an actual stereoscopic image, but at least my brain is used to seeing in 3D only with both eyes open.

[Arwin]

It just shows that there are very many things your brain uses to determine depth, not just stereoscopy. My cat's showing a lot of that as well, as he's had to have one eye removed, but hasn't missed a single jump since.

[Blazkowicz]

when playing the old Mafia game I found myself seeing the depth even though there was no stereoscopy involved. I was running the game with crazy amounts of anti-aliasing (16xS, or 9x supersampling)

I thought I hallucinated and wondered what I drank or smoked but maybe the game was just giving ideal perception cues with its clear cut perspective lines, 3rd party action, "realistic" everyday scenery, and perhaps strong immersion with the high IQ (power lines weren't the usual disjointed and jagged mess)

[Mendel]

Interesting. I think I´ve spent many hours googling and searching for all kinds of optical illusions at least 3 times a year (during boring nightshifts) and I´ve never ran into this wiggle stereoscopy thing.

Totally useless for any practical solution, but very interesting

edit: Still. It would be interesting to see if someone would make a short movie using this technology.
Or something like a 10 second animation, where there is 25 different frames per second, except every frame is made of 5 or so wiggle frames of the same frame in many viewpoints. (so 125 images per second as a result)

My guess is it would look like a mess but I don´t know

[Davros]

I think it could be done in a game you just need 2 (or more viewports) and switch between them,
not sure it would work with a movable image.

ps:
Quake II AbSIRD
I can only complete it because I know the levels off by heart I could imagine it to be very difficult for someone who has naver played q2 before
http://www.leweyg.com/download/SIRD/q2/index.html

[Arwin]

Well, let's just say I'm happy I can generally just press CTRL-T and get real stereoscopy

[Mendel]

Originally Posted by PixResearch

You can do a very similar thing with panning/scrolling images.

Any examples of this?

(I still don´t really understand why this effect then doesn´t come up in something like parallax scrolling platformer games and such.)

[PixResearch]

Originally Posted by Mendel

Any examples of this?

(I still don´t really understand why this effect then doesn´t come up in something like parallax scrolling platformer games and such.)

Sorry, I should have been clearer...
The scrolling techniques only work when you slow the brain's processing of one eye view (e.g. put a darkend filter in front of one eye). This takes a single image and effectively recreates an offset view of the moving objects going into one eye.

http://en.wikipedia.org/wiki/Pulfrich_effect
http://www.youtube.com/watch?v=1mnWI_u_zBg
http://www.youtube.com/watch?v=p7hMaPW26bM
etc

[Silent_Buddha]

Originally Posted by Grall

It's creepy that the effect remains even when one eye is closed. Logically it's not surprising, since it's not an actual stereoscopic image, but at least my brain is used to seeing in 3D only with both eyes open.

That's because this doesn't rely on or try to reproduce stereoscopic 3D. It uses the fact that your mind is used to viewing objects in motion or you in motion relative to objects.

In this case these faux 3D images are reproducing the effect you get with a spinning object or when you actively walk around an object.

If an object spins such that the closes edge moves to the right then your mind knows that the farther edge should shift to the left.

In a similar way if you walk around an object moving to the right, the nearest edge appears to shift to the left while the farther edge appears to shift to the right.

Rapidly toggle that back and forth and your mind is tricked into think you are moving your head rapidly from side to side staying equidistant from the center of the object (image in this case).

That doesn't rely on stereoscopic vision and hence works just fine with one eye since that is how we have observed the real world to react based on your head movement or the movement of an object when it spins.

If the image just represented a spin in one direction, your mind wouldn't get fooled as it would see it in constant motion relative to the other things on your screen. It's the rapid back and forth movement that is able to introduce just enough randomness to the image that it fools your brain into interpreting it that way.

Regards,
SB

[Ethatron]

You mean as a one-eyed person one could get depth-perception back again? I just tried it (though I have two healthy eyes :P), it kind of works for near objects if you don't move the head too fast, there is kind of a specific frequency which resonates, but I guess it won't work at the side of a street.

[Silent_Buddha]

Originally Posted by Ethatron

You mean as a one-eyed person one could get depth-perception back again? I just tried it (though I have two healthy eyes :P), it kind of works for near objects if you don't move the head too fast, there is kind of a specific frequency which resonates, but I guess it won't work at the side of a street.

It basically works with how your mind is trained to interpret things around you in real life via what it see's everyday.

So yes up to a point if you had depth perception via 2 eyes previously, and lost one eye, this would give the illusion of depth still. Just like you would if you did what you just did with one eye closed.

I'd imagine that given enough time even that will disappear, however, as your mind adjusts to only using a single eye to view the world. Although other illusions would still work. Like that one thing done with the wii sensor and a TV, where what is presented on screen reflects where the location of your head is.

That is something I'd love to see on the desktop. It'd be subtle but would add the illusion of depth to...say the desktop for example. Have 3d objects (icons, whatever) on the desktop and something that can track the movement and location (distance from screen) of your head/eyes. This then renders everything relative to the location of your head/eyes. It would give the illusion of depth nearly as good as stereoscopic glasses when you move your head. The drawback, of course, is that once you stop moving your head, the illusion will fade away as you are still ultimately looking at a 2D object. But it would have that subtle little wow effect each time you shifted in your chair.

Regards,
SB

[Kaizer]

This thread needs a bit of QI...

http://www.youtube.com/watch?v=ORoTCBrCKIQ

Seems our visual sense does quite a bit of semantic interpretation in addition to merely giving us the 2D/3D "image"

[Davros]

I ve got it you need a turntable that wiggles your monitor

[fellix]