Modern Approaches to Creating Highly Undetectable Stegosystems (HUGO Systems)

This chapter's primary goal is to provide a comprehensive approach to the development of new highly undetectable stegosystems that greatly complicate their steganalysis. The authors propose several implementations of highly undetectable stegosystems, the so-called HUGO systems, using an integrated approach to their synthesis. This approach most fully considers the features of transmitting hidden messages over highly noisy communication channels. At the stage of embedding hidden messages, the authors suggest actively using their discrete transformations. The authors also propose increasing the secrecy of secret messages by converting them to a form that resembles natural noise. The authors use a discrete chaotic decomposition of the Arnold cat map (ACM) to do this. The authors also suggest using highly efficient noise-tolerant encoding and multi-threshold decoding to combat interference in the communication channel and an embedding algorithm. The authors also describe two original stegosystems ±HUGO and ⨁HUGO and test results confirming their effectiveness.

Blind image watermarking scheme based on lowest energy contourlet transform coefficient and modified arnold cat/ikeda maps

<span>The widespread of global internet has led to the need for developing new methods of protecting multimedia information from exploitation, alteration or forgery, illegal distribution, and manipulation. An attacker is quickly and illegally distributing or changing multimedia information by using various means of computer technology. For detecting this manipulation, this paper suggests blind watermark image inside a host image for observing in the receiver. If the watermark image was retrieved, then the host image was not attacked or manipulated. While if not retrieved, in this case, the image was attacked. The proposed method is depending on a decomposition of the host image using lowest energy sub-bands of Contourlet transform (4-levels), with scrambling by Ikeda map of the watermark image, and selecting new positions by modified Arnold Cat map. This will produce more security and safety, as well as provide more difficulty or prevent hacking. The obtained results confirm the robustness against attacks and more effectiveness of the presented scheme compared with the other similar works. Also, using lowest energy sub-bands will expand area of embedding and this part will be considered in the future works with the color images.</span>

Security of Digital Images Based on 3D Arnold Cat Map and Elliptic Curve

Security of digital data is an important task in the present era. In this paper, we propose a new scheme of digital image encryption and decryption method based on three-dimensional (3D) Arnold cat map (ACM) and elliptic curve. In this proposed encryption method, we have applied 3D ACM on the digital color image which performs the dual encryption first, it performs the permutation and second, it performs the substitution of image pixels. After that, elliptic curve cryptography (ECC) is used to encrypt the image, for this a mapping method is proposed to convert the pixels of the image as points on the elliptic curve. Further, a mapping inverting method is proposed for decryption and then 3D inverse Arnold cat map (iACM) is applied to get the original image. The statistical and security analyses are done on various images and the experimental results show the robustness of the proposed method.