The filters collection harks back to the late 80's, when various text filters were written to munge written language in amusing ways. The earliest and best known were legends such as the Swiedish Chef filter and B1FF.

Since 1996 I have been collecting these filters, keeping them running, and chasing down the copyright and licence information that lets me legally distribute them. In many cases this information is not available and so I have had to rewrite many of the early filters from scratch. The current filters package contains more than 20 filters.

The GNU project hosts a similar collection of filters, the GNU talkfilters. I would like to merge the two collections, but potential copyright issues (see talkfilters-email) in the talkfilters and an inability to get a response back from its maintainer have prevented this so far. On the other hand, I do have to thank the many authors of filters who responded to my queries about getting a proper copyright and license statement on them, often decades after they had written the original code.

To download, apt-get install filters or git clone git://


version 2.54

filters 2.54 released with these changes

  • Fix UTF-8 handling in uniencode. Closes: #508003 Thanks, Marius Gavrilescu.
  • Improve layout and build process. Thanks, Marius Gavrilescu.
  • Replace fread with getchar in nethackify. Thanks, Marius Gavrilescu.
  • Fix NAME section of manpage. Closes: #775035 Thanks, Marius Gavrilescu.
  • Remove SAMPLES file for deterministic builds.
  • Makefile: Propagate input CFLAGS and LDFLAGS through to the compiler to allow eg, building with hardening. Thanks, Marius Gavrilescu.
version 2.52

filters 2.52 released with these changes

  • Rename lolcat to LOLCAT to avoid collision with a fine rainbow colored cat. Closes: #760910