Steganography algorithms robust to active attacs

The aim of this work is to develop a steganographic algorithm, which is able to organize covert channel data in terms of a targeted attack on a container. Robust against an active attack on a steganographic algorithms is used to solve a number of applied problems. For example, the task of adding a new functionality to a fixed format. It is proposed to use the state diagram to describe the possible transformations of a digital object as a result of the attacks. The transition between the two states is characterized by the distortion introduced in the original object, and if the distortion produces a number of different objects, the corresponding state in the diagram is marked with infinity symbolizes sign which the attitude of "one-to-many". Thus, the problem of constructing robust against an active attack steganography is reduced to obtaining an algorithm that is able to extract hidden information from all the states in the diagram. There are two theoretical methods of construction robust against an active attack steganography: method of reducing a plurality of containers and method of assessing distortion. The first method is based on the assumption that among a plurality of containers. There can be such containers that the attack does not destroy embedded information. The second method allows you to build a robust embedding algorithm if the distortion introduced by the attack is limited by modulo in a metric space of containers. This paper gives a practical application of the proposed methods for the construction of steganography system that is robust against conversion of color images to grayscale. The program implementation in the programming language Python is given.