Re: Pterodactyl Gnus v0.5 is released

["François Pinard" <pinard@iro.umontreal.ca>]

Lars Magne Ingebrigtsen <larsi@gnus.org> writes:

> Michael Harnois <mharnois@sbt.net> writes:

> > It's 54 bytes long. That certainly does represent a size reduction ...

> It's the new, effective, but instable compression technology.  The
> size spontaneously expanded to ~700kb a few jiffies ago.

The technology Lars used is very effective compression.  Here is
the algorithm.  Consider that a file is nothing more than an sequence
alternating 0-runs with 1-runs (the first 0-run has zero bits if the file
starts with a 1).  Using the alternating principle, replace each X-run by
the binary expression of its length.  So, you have the length of the first
0-run, and the length of the first 1-run, the length of the second 0-run,
the length of the second 1-run, etc.  These lengths convey all information
needed to recover the original file, so replace the original file by the
file made up of all lengths.  Iterate the compression on this new file, and
continue this way until the file does not shrink anymore.  This _is_ quite
effective compression.  After that, who bothers about decompression? :-)

-- 
François Pinard                            mailto:pinard@iro.umontreal.ca
Join the free Translation Project!    http://www.iro.umontreal.ca/~pinard