Steganalysis: the investigation of hidden information

The goal of steganography is to avoid drawing suspicion to the transmission of a hidden message. If suspicion is raised, then this goal is defeated. Discovering and rendering useless such covert messages is a new art form known as steganalysis. The authors provide an overview of some characteristics in information hiding methods that direct the steganalyst to the existence of a hidden message and identify where to look for hidden information.