Compressing alt.sex.pictures files

[Kent Paul Dolan]

In article <1990Aug29.000054.28444 at murdoch.acc.Virginia.EDU> dmm0t at hudson.acc.Virginia.EDU (David M. Meyer) writes:
>Compressing a.s.p would be a wonderful idea, except that almost all
>of the traffic is in .GIF pictures, which are already compressed
>pretty thoroughly.  I'm not sure exactly what the methods used
>are, but neither PKZIP nor compress actually shrinks .GIF files.

Right.  The idea is to come up with a much better way of compressing the
raw pixel data, and then incorporate that new compression scheme in "all"
the picture handling software.  This means the compression scheme must be
1) public domain, 2) reasonably, but not necessarily blindingly fast (it
is worth spending _hours_ to compress a file if you can make it 20% the
size any other compression scheme can make it, and then save that space
on every USENet site and every home computer's storage!), 3) able to
decompress very fast (paying a high decompression cost at every site doesn't
have the same economic balance that a high compression cost at the site of
origin has), 4) available in source code; and 5) widely ported.

This is not a short term "fix" that we can band-aid into a.s.p next week;
but if a highly effective scheme is found, it will spread itself fast
enough; the economic motivation to save disk space is everywhere.

Note that it is sufficient that the scheme found compress _realistic_image_
data well; it doesn't have to compress random input at all well, nor does
it need to do well on text; image data is a worthwhile target for compression
in its own right, and at its present rate of dissemination, will probably
rapidly overwhelm in size the sum of all other stored machine readable data.

Kent, the man from xanth.
<xanthian at Zorch.SF-Bay.ORG> <xanthian at well.sf.ca.us>