A mimic function changes a file so it assumes the statistical properties of another file . That is, if is the probability of some substring occurring in , then a mimic function , recodes so that approximates for all strings of length less than some . It is commonly considered to be one of the basic techniques for hiding information, often called steganography.
The simplest mimic functions use simple statistical models to pick the symbols in the output. If the statistical model says that item occurs with probability and item occurs with probability , then a random number is used to choose between outputting or with probability or respectively.
Even more sophisticated models use reversible Turing machines.
Referencesedit
Wayner, Peter (December 1990). Mimic Functions (Report). Cornell University Department of Computer Science. TR 90-1176.
mimic, function, this, article, includes, list, references, related, reading, external, links, sources, remain, unclear, because, lacks, inline, citations, please, help, improve, this, article, introducing, more, precise, citations, june, 2010, learn, when, re. This article includes a list of references related reading or external links but its sources remain unclear because it lacks inline citations Please help improve this article by introducing more precise citations June 2010 Learn how and when to remove this template message A mimic function changes a file A displaystyle A so it assumes the statistical properties of another file B displaystyle B That is if p t A displaystyle p t A is the probability of some substring t displaystyle t occurring in A displaystyle A then a mimic function f displaystyle f recodes A displaystyle A so that p t f A displaystyle p t f A approximates p t B displaystyle p t B for all strings t displaystyle t of length less than some n displaystyle n It is commonly considered to be one of the basic techniques for hiding information often called steganography The simplest mimic functions use simple statistical models to pick the symbols in the output If the statistical model says that item x displaystyle x occurs with probability p x A displaystyle p x A and item y displaystyle y occurs with probability p y A displaystyle p y A then a random number is used to choose between outputting x displaystyle x or y displaystyle y with probability p x A displaystyle p x A or p y A displaystyle p y A respectively Even more sophisticated models use reversible Turing machines References editWayner Peter December 1990 Mimic Functions Report Cornell University Department of Computer Science TR 90 1176 Wayner Peter July 1992 Mimic Functions Cryptologia 16 3 193 214 doi 10 1080 0161 119291866883 Wayner Peter 2008 Disappearing Cryptography 3rd ed Morgan Kaufmann ISBN 978 0123744791 nbsp This cryptography related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Mimic function amp oldid 1130147501, wikipedia, wiki, book, books, library,
