Single image 3D pics (Magic Eye style)

Have you walked through a mall lately? These days, as you wander past
most of the poster shops, there will be a large group of people
staring at the same poster with surprisingly weird expressions on
their faces. Some will be in the initial stages of denial or
rejection---they will be concentrating, some slowly rocking their
heads backwards and forwards, searching for an image that they have
never seen before. Others will be grinning from ear to ear, pointing
at the poster, chuckling with their friends that a member of their
group hasn't seem them yet.  "Come on Bill, come on!", they cry and as
Bill gets increasingly more frustrated he concentrates harder and
harder, until finally (if he's lucky) he sees a true 3D image, without
the need for special glasses or equipment.

These pictures are known as Single Image Random Dot Stereograms
(SIRDS), or Single Image Stereograms (SIS) depending on whether the
picture contains random dots as a base for the 3D effect, or a
repetitive pattern. Unfortunately, each commercial company has
labelled them differently. Shop owners generally don't know what you
mean, unless you say "Hollusion" or one of the many other specific
names.

(Description from SIRDS-FAQ by Stuart Inglis)

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]               270216  270216 100.0% -lh0- 515e Sep  4  1994 hiv.gif
[generic]                  467     873  53.5% -lh5- b9d2 Sep  4  1994 hiv.gif.info
[generic]               383416  383416 100.0% -lh0- dd57 Sep  4  1994 Julia_1.gif
[generic]                  468     873  53.6% -lh5- 520e Sep  4  1994 Julia_1.gif.info
[generic]               249293  249293 100.0% -lh0- 7970 Sep  4  1994 maelstrom.gif
[generic]                  467     873  53.5% -lh5- b7e2 Sep  4  1994 maelstrom.gif.info
[generic]                65888   65888 100.0% -lh0- 8e08 Sep  4  1994 mandelbrot.gif
[generic]                  469     873  53.7% -lh5- 5653 Sep  4  1994 mandelbrot.gif.info
[generic]                72590   72590 100.0% -lh0- 8ff0 Sep  4  1994 map.gif
[generic]                  468     873  53.6% -lh5- 94f6 Sep  4  1994 map.gif.info
[generic]                43333   43333 100.0% -lh0- 47c0 Sep  4  1994 mindtest.gif
[generic]                  470     873  53.8% -lh5- 1923 Sep  4  1994 mindtest.gif.info
[generic]               213604  213604 100.0% -lh0- 0d79 Sep  4  1994 mono_splash.gif
[generic]                  471     873  54.0% -lh5- 317b Sep  4  1994 mono_splash.gif.info
[generic]               228202  228202 100.0% -lh0- 4ec5 Sep  4  1994 no6.gif
[generic]                  468     873  53.6% -lh5- bd46 Sep  4  1994 no6.gif.info
[generic]               267985  267985 100.0% -lh0- dbf5 Sep  4  1994 nsa_sis.gif
[generic]                  470     873  53.8% -lh5- ce1e Sep  4  1994 nsa_sis.gif.info
[generic]                  428     679  63.0% -lh5- 6db5 Sep  4  1994 nsa_sis.txt
[generic]                  357     544  65.6% -lh5- c87e Sep  4  1994 PlanesBirdsBalls.txt
[generic]                  893    1640  54.5% -lh5- 8949 Sep  4  1994 Product-Info
[generic]                43429   43429 100.0% -lh0- 3d7a Sep  4  1994 revcone.gif
[generic]                  468     873  53.6% -lh5- 923e Sep  4  1994 revcone.gif.info
[generic]                31285   31285 100.0% -lh0- b8f9 Sep  4  1994 river.gif
[generic]                  469     873  53.7% -lh5- b193 Sep  4  1994 river.gif.info
[generic]               153725  153725 100.0% -lh0- ef1a Sep  4  1994 sick.gif
[generic]                  468     873  53.6% -lh5- 9da6 Sep  4  1994 sick.gif.info
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        27 files 2030267 2036305  99.7%            Dec  1  1994