fleischer@iccgcc.decnet.ab.com (04/25/91)
I saw the most *amazing* "3D" black and white photocopy of an advertisement by PENTICA. It looked like a random patern of squiggles in a box with 2 large black dots above. When you shift the focus of your eyes to make the 2 dots overlap, this flat XEROX'd picture turns 3D. It's like you're looking through a window to a picture about 1 foot below the paper with letters and numbers at various heights above the picture. Does anyone know how this was done? Is there PC software that will let you build these and print them on a laser printer? Is there a collection of these? Who did the theory and development? Does it require more resolution than exists on a VGA display? IS there a dynamic/moving version? I requested more information from PENTICA, but I don't expect a very detailed reply.
peda@simplicity.Stanford.EDU (Bill Codding) (04/30/91)
In article <4354.2816ba40@iccgcc.decnet.ab.com> fleischer@iccgcc.decnet.ab.com writes:
I saw the most *amazing* "3D" black and white photocopy of an
advertisement by PENTICA. It looked like a random patern of squiggles in
a box with 2 large black dots above. When you shift the focus of your eyes
to make the 2 dots overlap, this flat XEROX'd picture turns 3D. It's
like you're looking through a window to a picture about 1 foot below the
paper with letters and numbers at various heights above the picture.
Does anyone know how this was done? Is there PC software that will let
you build these and print them on a laser printer? Is there a collection of
these? Who did the theory and development? Does it require more resolution
than exists on a VGA display? IS there a dynamic/moving version?
Sounds like what you are describing is an example of a simple artificial
stereo pair.
I *think* that an example of this exists in the book
_Procedural Elements for Computer Graphics_ by David F. Rogers,
McGraw-Hill, 1985.
Check before you buy, because I am not 100% positive where I saw it
(I returned the book to its rightful owner some time ago.)
------------------------------------------------------------------------
Bill Codding (415)493-3554 (w)
Research Engineer (415)751-5484 (h)
P.E.D.A. peda@simplicity.Stanford.EDU
------------------------------------------------------------------------stevea@poincare.geom.umn.edu (stevea) (04/30/91)
In article <4354.2816ba40@iccgcc.decnet.ab.com> fleischer@iccgcc.decnet.ab.com writes: >I saw the most *amazing* "3D" black and white photocopy of an >advertisement by PENTICA. It looked like a random patern of squiggles in >a box with 2 large black dots above. When you shift the focus of your eyes >to make the 2 dots overlap, this flat XEROX'd picture turns 3D. It's >like you're looking through a window to a picture about 1 foot below the >paper with letters and numbers at various heights above the picture. > >Does anyone know how this was done? Is there PC software that will let >you build these and print them on a laser printer? Is there a collection of >these? Who did the theory and development? Does it require more resolution >than exists on a VGA display? IS there a dynamic/moving version? > >I requested more information from PENTICA, but I don't expect a very >detailed reply. Sure, I've seen these around. They're called "random dot stereograms", and were invented by a psychologist named Julesz. (I forgot his first name.) He developed it 20 or 25 years ago, but the technique's mostly lain dormant since then. Until now. There was an article in a recent issue of _Mathematica Journal_, about how to create these. (Using mathematica, I guess.) I don't know which issue. Check out your local shopping districts too. We got a huge poster for our office from a shop that sells holograms and things. The poster was produced by Oliphant Research. It's about 3'x 2', and full of geometric shapes that seem to rise out of the paper. -Steven Anderson stevea@geom.umn.edu Geometry Center of Minnesota
a-peterb@microsoft.UUCP (Peter BRUINSMA) (04/30/91)
In article <4354.2816ba40@iccgcc.decnet.ab.com> fleischer@iccgcc.decnet.ab.com writes: >I saw the most *amazing* "3D" black and white photocopy of an >advertisement by PENTICA. It looked like a random patern of squiggles in >a box with 2 large black dots above. When you shift the focus of your eyes >to make the 2 dots overlap, this flat XEROX'd picture turns 3D. It's >like you're looking through a window to a picture about 1 foot below the >paper with letters and numbers at various heights above the picture. > >Does anyone know how this was done? What you were looking at was a pair of stereoscopic images. These used to be a very common form of entertainment during the beginning of this century. Hundreds of thousands of viewers were sold. They consisted of a holder in which you could mount your stereo pair print, and two holes or lenses, fixed at a certain distance. The idea is that each eye sees a scene at a slightly different angle. If you look at a scene with only one eye at a time you will see that everything shifts position. If you were to take two photographs at about 5 to 10 inches apart, and you mounted the prints side by side (left image on the left, right image on the right) then you could view these using a special purpose viewer. If you don't have such a viewer then you could train your brain/eyes to 'free view' the images. It is for that purpose that those two black dots were placed above the images. All you have to do is merge them, as you have already found out. Is there PC software that will let >you build these and print them on a laser printer? Any program in which you can specify a viewpoint for viewing a 3D scene and lets you subsequently print it would allow you to view the scene twice, each, say, 10 inches apart from the other. I don't know anything out there though that will do that... Is there a collection of >these? Yes. If you are seriously interested in this 3D stuff you can Email uunet!bfmny0!3d-request Ask if you can join the list. Who did the theory and development? This idea was probably discovered independently way before the 1900's. I guess I don't have any references here... Does it require more resolution >than exists on a VGA display? No, but the result is obviously more fun on higher resolution displays. IS there a dynamic/moving version? I heard of chemical models rotating and that sort of thing. Usually those really nice workstations use LCD shutter glasses which allow you to see the left and right images sequentially in color etc. > >I requested more information from PENTICA, but I don't expect a very >detailed reply. Never heard of them. You also may want to check out a magazine called "ShutterBug". Good luck! Peter Bruinsma a-peterb@microsoft.UUCP Any soelling errors were vi's, not mine. i
barham@adm.csc.ncsu.edu (Paul T. Barham) (04/30/91)
What you saw may have actually have been an autostereogram. From the abstract of a paper describing autostereograms: "A new technique for the presentation of cyclopean stereograms is described, in which complete information for the two eyes is contained in a single, printed image. Such "autostereograms" may be generated to contain an unlimited range of 3-D depth forms within certain constraints." The article is entitled "The Autostereogram" and appears in the SPIE Proceedings, Volume 1256, Stereoscopic Displays and Applications. The authors are Tyler and Clarke. Hope this helps. *************************************** Paul T. Barham barham@adm.csc.ncsu.edu Computer Science Department North Carolina State University ***************************************
pinard@IRO.UMontreal.CA (Francois Pinard) (04/30/91)
In article <1991Apr30.112127.2524@ncsu.edu> barham@adm.csc.ncsu.edu (Paul T. Barham) writes:
What you saw may have actually have been an autostereogram.
On a sligntly different topic, the term `3D photocopy' reminds me of
an apparitus which is used for blind people, able to reproduce a 3D
objects, given certain constraints. You put the object in the
machine, and a sheet of special plastic over it, and you close the
door. The plastic is heated (not much) and pumped down over the
object, molding it in fact.
This was used to supplement audio tapes of technical books with the
technical drawings. The drawings were reproduced with wires, and then
duplicated through the 3D photocopier, so blind people could better
follow and understand the spoken descriptions.
--
Franc,ois Pinard ``Vivement GNU!'' pinard@iro.umontreal.ca
(514) 588-4656 cp 886 L'Epiphanie (Qc) J0K 1J0 ...!uunet!iros1!pinarddbg@sinix.UUCP (David George) (05/22/91)
In article <72100@microsoft.UUCP> a-peterb@microsoft.UUCP (Peter BRUINSMA) writes: > >What you were looking at was a pair of stereoscopic images. These used to >be a very common form of entertainment during the beginning of this century. >Hundreds of thousands of viewers were sold. They consisted of a holder >in which you could mount your stereo pair print, and two holes or lenses, >fixed at a certain distance. The idea is that each eye sees a scene at a >slightly different angle. If you look at a scene with only one eye at a >time you will see that everything shifts position. If you were to take two >photographs at about 5 to 10 inches apart, and you mounted the prints >side by side (left image on the left, right image on the right) then you >could view these using a special purpose viewer. If you don't have such a >viewer then you could train your brain/eyes to 'free view' the images. >It is for that purpose that those two black dots were placed above the images. >All you have to do is merge them, as you have already found out. > >Any program in which you can specify a viewpoint for viewing a 3D scene >and lets you subsequently print it would allow you to view the scene twice, >each, say, 10 inches apart from the other. I don't know anything out there >though that will do that... > >I heard of chemical models rotating and that sort of thing. Usually those >really nice workstations use LCD shutter glasses which allow you to see the >left and right images sequentially in color etc. > >Peter Bruinsma >a-peterb@microsoft.UUCP > I saw a similar system demonstrated on a BBC Science Program (Tomorrows World) about 10 years ago. They used an interlaced monitor and displayed one view on one half frame and another slightly different view on the other. The effect was a 3d image. This was useful where the operator required spatial information... such as remote controlling a robot, the robot being mounted with two cameras. Anyone seen any development of this system? It was only black and white. David.