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Evolutionary rule generation for signature-based cover selection steganography
, Article Neural Network World ; Volume 20, Issue 3 , 2010 , Pages 297-316 ; 12100552 (ISSN) ; Jamzad, M ; Sharif University of Technology
2010
Abstract
A novel approach for selecting proper cover images in steganography is presented in this paper. The proposed approach consists of two stages. The first stage is an evolutionary algorithm that extracts the signature of cover images against stego images in the form of fuzzy if-then rules. This algorithm is based on an iterative rule learning approach to construct an accurate fuzzy rule base. The rule base is generated in an incremental way by optimizing one fuzzy rule at a time using an evolutionary algorithm. In the second stage of the proposed approach, the fuzzy rules generated in the first stage are used for selecting suitable cover images for steganography. We applied our approach to some...
Detection of LSB replacement and LSB matching steganography using gray level run length matrix
, Article IIH-MSP 2009 - 2009 5th International Conference on Intelligent Information Hiding and Multimedia Signal Processing, 12 September 2009 through 14 September 2009, Kyoto ; 2009 , Pages 787-790 ; 9780769537627 (ISBN) ; Ghaemmaghami, S ; Sharif University of Technology
Abstract
This paper introduces a novel method to detect the typical LSB (Least Significant Bit) embedding and the LSB matching steganography methods applied to grayscale images. The proposed method determines the changes made to some selected features extracted from the gray level run length matrix. It is shown that the run length characteristics can significantly be affected by the embedded message bits, so can be employed as a measure that is quite sensitive to the arrangements of the image pixel values. The extracted features are examined by a nonlinear SVM (Support Vector Machine) classifier with quadratic kernel that can distinguish between stego and clean images. Experimental results are given...
A new robust non-blind digital watermarking scheme in contourlet domain
, Article IEEE International Symposium on Signal Processing and Information Technology, ISSPIT 2009, 14 December 2009 through 16 December 2009, Ajman ; 2009 , Pages 20-25 ; 9781424459506 (ISBN) ; Tirdad, P ; Rabiee, H. R ; Sharif University of Technology
Abstract
In this paper, we propose a new multiresolution watermarking method for still images based on the Contourlet Transform (CT). In our algorithm, the watermark is a grayscale image which is embedded into the host image in its contourlet domain. We demonstrate that in comparison with other methods, the proposed method enables us to embed more amount of data into the host image without degrading its perceptual quality. The experimental results show robustness against several common watermarking attacks such as compression, adding noise, and filtering. ©2009 IEEE
A robust spread spectrum watermarking method using two levels DCT
, Article International Journal of Electronic Security and Digital Forensics ; Volume 2, Issue 3 , 2009 , Pages 280-305 ; 1751911X (ISSN) ; Jamzad, M ; Sharif University of Technology
2009
Abstract
In this paper, a DCT-based blind watermarking scheme based on spread spectrum communications is proposed. We perform block-based DCT on the host image; then using the DC coefficients of each block, we construct a low-resolution approximation image. We apply block-based DCT on this approximation image, then watermark is embedded by adding a pseudo random noise sequence into its high frequencies. In detection stage, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method, higher robustness is obtained because of embedding...
A new spread spectrum watermarking method using two levels DCT
, Article International Journal of Electronic Security and Digital Forensics ; Volume 3, Issue 1 , 2010 , Pages 1-26 ; 1751911X (ISSN) ; Jamzad, M ; Sharif University of Technology
2010
Abstract
In this paper, a discrete cosine transform (DCT) based blind watermarking scheme based on spread spectrum communications is proposed. We perform block-based DCT (BDCT) on the host image; then using the DC coefficients of each block, we construct a low-resolution approximation image. We apply BDCT on this approximation image, then watermark is embedded by adding a pseudo random noise sequence into its high frequencies. In detection stage, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method, higher robustness is obtained...
The effective mechanical properties and the interfacial characterization of CNT reinforced nanocomposites
, Article Proceedings of SPIE - The International Society for Optical Engineering, 9 March 2009 through 11 March 2009, San Diego, CA ; Volume 7294 , 2009 ; 0277786X (ISSN); 9780819475541 (ISBN) ; Naghdabadi, R ; The International Society for Optical Engineering (SPIE) ; Sharif University of Technology
2009
Abstract
A small volume fraction of Carbon Nanotubes (CNTs) added in a polymeric matrix increases significantly the mechanical properties of the polymers. It is experimentally determined from the TEM images of CNT-based nanocomposites that nanotubes don't stand straight in their embedded matrix and they have some curvature in their shape. The load transfer mechanism between CNT and polymer matrix is also one of the most important issues which is not understood explicitly, yet. In this paper a wavy Single Walled Carbon Nanotube (SWCNT) is modeled as inclusion in a polymer matrix and its effective mechanical properties is studied. This model is based on using 3-D Representive Volume Element (RVE) with...