home *** CD-ROM | disk | FTP | other *** search
- This package includes yabba and unyabba, portable implementations of Y
- coding. Y coding is unpatented---unlike the LZW coding used by compress
- and the LZ78 variants used by most other dictionary compressors. Y also
- gives somewhat better compression than LZW.
-
- As an extra bonus, this package also includes whap and unwhap, portable
- implementations of AP coding. AP coding is patented, but like Y it is
- more effective than LZW. whap runs about as fast as compress and, in its
- default configuration, uses less memory; unwhap runs as fast as
- uncompress and uses less than half as much memory.
-
- The entire package is public-domain. You can copy my Y code into any
- application without fear of copyrights or patents. Be aware, however,
- that the current implementation is probably not too close to optimal,
- and I am actively searching for a better method. If AP were not patented
- I would recommend that you use it instead. For more information see
- PATENTS in the package.
-
- ---Dan Bernstein, brnstnd@nyu.edu
-