MIMIC FUNCTIONS
Peter Wayner · Cryptologia · 1992
A mimic function changes a file A so it assumes the statistical properties of another file B. That is, if p(t, A) is the probability of some substring t occurring in A, then a mimic function f, recodes A so that p(t, f(A)) approximates p(t, B) for all strings t of length less than some n. This paper describes the algorithm for computing mimic functions and compares the algorithm with its functional inverse, Huffman coding. The paper also provides a description of more robust and more general mimic functions which can be defined using context-free grammars and van Wijngaarden grammars.