In this paper, we introduce a DCT based steganographic method for gray scale images. The embedding approach is designed to reach efficient tradeoff among the three conflicting goals; maximizing the amount of hidden message, minimizing distortion between the cover image and stego-image,and maximizing the robustness of embedding. The main idea of the method is to create a safe embedding area in the middle and high frequency region of the DCT domain using a magnitude modulation technique. The magnitude modulation is applied using uniform quantization with magnitude Adder/Subtractor modules. The conducted test results indicated that the proposed method satisfy high capacity, high preservation of perceptual and statistical properties of the steg

    Data hiding strategies have recently gained popularity in different fields; Digital watermark technology was developed for hiding copyright information in the image visually or invisibly. Today, 3D model technology has the potential to alter the field because it allows for the production of sophisticated structures and forms that were previously impossible to achieve. In this paper, a new watermarking method for the 3D model is presented. The proposed method is based on the geometrical and topology properties of the 3D model surface to increase the security. The geometrical properties are based on computing the mean curvature for a surface and topology based on the number of edges around each vertex, the vertices

Mit dem Fall der Berliner Mauer am 9. November 1989 und dem damit
einhergehenden Verschwinden der DDR aus der politischen Bühne im Jahre 1990
„haben sich nicht nur politische Systeme umgewälzt, sondern auch die Menschen
in ihnen haben ihre Maßstäbe und Perspektiven geändert, unter ihnen Kunstrichter
und Leser.“1 Alles, was bis zum Tag der Wiedervereinigung im Bereich der Kultur
galt, fiel über den Haufen.2 Christa Wolf, die in der DDR eine Leitfigur des
öffentlichen und kulturellen Lebens war und an der Spitze der einflussreichen
Schriftsteller stand, landete im vereinigten Deutschland „immerhin noch auf Platz
25, ein erstaunliches Resultat nach all den Vorwürfen“3, die gegen ihr Werk und
ihre m

Resumé

La Peste, paru en 1947 et qui reçoit le prix des critiques acquiert a Camus  une notoriété universelle, il reçoit en 1957 le prix Nobel pour une œuvre qui, selon les termes de l’Académie suédoise : « met en lumière les problèmes se posant de nos jours à la conscience des hommes ». A Oran où il n’arrive jamais rien, quelque chose va arriver. On découvre un rat mort, couvert de sang. Deux jours après on en trouve des centaines, puis des milliers. Deux semaines plus tard, un homme meurt d’une maladie, décrite avec précision, mais sans recherche de l’horreur. Après cet événement, on signale une dizaine, puis une vingtaine de cas de fiè

Rivest Cipher 4 (RC4) is an efficient stream cipher that is commonly used in internet protocols. However, there are several flaws in the key scheduling algorithm (KSA) of RC4. The contribution of this paper is to overcome some of these weaknesses by proposing a new version of KSA coined as modified KSA . In the initial state of the array is suggested to contain random values instead of the identity permutation. Moreover, the permutation of the array is modified to depend on the key value itself. The proposed performance is assessed in terms of cipher secrecy, randomness test and time under a set of experiments with variable key size and different plaintext size. The results show that the RC4 with improves the randomness and secrecy with

Some maps of the chaotic firefly algorithm were selected to select variables for data on blood diseases and blood vessels obtained from Nasiriyah General Hospital where the data were tested and tracking the distribution of Gamma and it was concluded that a Chebyshevmap method is more efficient than a Sinusoidal map method through mean square error criterion.

Steganography art is a technique for hiding information where the unsuspicious cover signal carrying the secret information. Good steganography technique must be includes the important criterions robustness, security, imperceptibility and capacity. The improving each one of these criterions is affects on the others, because of these criterions are overlapped each other.  In this work, a good high capacity audio steganography safely method has been proposed based on LSB random replacing of encrypted cover with encrypted message bits at random positions. The research also included a capacity studying for the audio file, speech or music, by safely manner to carrying secret images, so it is difficult for unauthorized persons to suspect