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by pablo1 2649 days ago
Don't know much about stereograms, two general questions:

a) Is it possilbe to render color images this way? b) Is it possible to have the random dots not change all the time? E.g. When I don't move in this example, I dont see the need to draw new random dots. Also when moving sideways e.g. would it be possible to keep the dots where they are, relative to the world?

1 comments

It's possible to use color in that the dots don't have to be black and white, and don't have to be totally random. The way an autostereogram works is that there's a repetitively tiled base image (or vertical column repeated horizontally). The stereographic angle information is encoded in mutations of the repeating image. That base image can be anything (including a photo).

However, this color image will not correspond in any way to the 3D geometry of the scene. I don't know of any way to get color information to correspond to BOTH the 3D geometry and the stereographic information (without using two images).

In the Wikipedia article on autostereogram [1] there is an example of a chess set [2] where the 2D image directly corresponds to the 3D autostereogram image. It is apparently a type of wallpaper autosterogram, instead of random dot, which requires horizontal repetition for the effect to work.

[1] https://en.wikipedia.org/wiki/Autostereogram [2] https://en.wikipedia.org/wiki/Autostereogram#/media/File:Che...

That picture in particular has a really interesting parallax effect - view it in stereo and move your head around. For me, the back rank seems to shift a lot with head position, even though the image itself is (obviously) stationary.

Regular Magic-Eye pictures do this too, but to a much less noticeable degree.

Interesting! I think this is possible here because the 3D geometry is also horizontally repetitive.