Description:

XDelta is a library interface and application program designed to
compute changes between files. These changes (deltas) are similar to
the output of the "diff" program in that they may be used to store and
transmit only the changes between files. However, unlike diff, the
output of XDelta is not expressed in a human-readable format--XDelta
can also also apply these deltas to a copy of the original file(s).
XDelta uses a fast, linear algorithm and performs well on both binary
and text files. XDelta typically outperforms GNU diff in both time
and generated-delta-size, even for plain text files. XDelta also
includes a simple implementation of the Rsync algorithm and several
advanced features for implementing RCS-like file-archival with.