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]               161174  161174 100.0% -lh0- 9751 Sep  4  1994 eggbox.gif
[generic]                  464     873  53.2% -lh5- 8d36 Sep  4  1994 eggbox.gif.info
[generic]                42917   42917 100.0% -lh0- 180c Sep  4  1994 enterpr2.gif
[generic]                  468     873  53.6% -lh5- 5409 Sep  4  1994 enterpr2.gif.info
[generic]               230144  230144 100.0% -lh0- cca6 Sep  4  1994 escher.gif
[generic]                  467     873  53.5% -lh5- 9230 Sep  4  1994 escher.gif.info
[generic]                49068   49068 100.0% -lh0- 5de1 Sep  4  1994 escher4.gif
[generic]                  465     873  53.3% -lh5- 50c8 Sep  4  1994 escher4.gif.info
[generic]                43074   43074 100.0% -lh0- f399 Sep  4  1994 escher5.gif
[generic]                  469     873  53.7% -lh5- 0fa7 Sep  4  1994 escher5.gif.info
[generic]                43302   43302 100.0% -lh0- 2667 Sep  4  1994 face.gif
[generic]                  468     873  53.6% -lh5- 8cb3 Sep  4  1994 face.gif.info
[generic]               268827  268827 100.0% -lh0- c3c8 Sep  4  1994 faeries.gif
[generic]                  466     873  53.4% -lh5- 89ac Sep  4  1994 faeries.gif.info
[generic]                32157   32157 100.0% -lh0- 42e8 Sep  4  1994 flatpic.gif
[generic]                  468     873  53.6% -lh5- 90cb Sep  4  1994 flatpic.gif.info
[generic]                49045   49045 100.0% -lh0- 18c6 Sep  4  1994 glassp1.gif
[generic]                  466     873  53.4% -lh5- 7297 Sep  4  1994 glassp1.gif.info
[generic]               169882  169882 100.0% -lh0- 4db0 Sep  4  1994 head.gif
[generic]                  470     873  53.8% -lh5- 6828 Sep  4  1994 head.gif.info
[generic]               120479  120479 100.0% -lh0- 491a Sep  4  1994 hidimg17.gif
[generic]                  471     873  54.0% -lh5- c831 Sep  4  1994 hidimg17.gif.info
[generic]                   45      45 100.0% -lh0- c351 Sep  4  1994 hidimg17.txt
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        23 files 1215256 1219717  99.6%            Dec  1  1994