Invented by
Peter Wayner in
1991, Mimic Functions are an application of
context-free grammars to the field of
Steganography. Using Mimic Functions one can
hide information in
innocuous form.
The power of Mimic Functions over other
Steganographic techniques is that the form that the hidden message takes is limited only by the imagination and resourcefulness of the grammar composer (see
spammimic for one possible implementation). Thus, one is not limited to the
least significant bits of graphics, sound or text files (all techniques which can be relatively easily
analyzed). Another way Mimic Functions resist
steganalysis is by having the hidden message take on the statistical properties of the innocuous source.
Mimic Functions are one of the most
underrated inventions in the field of Steganography.