Browsing by Author "Djebbar, Fatiha"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
Item Audio steganalysis based on lossless data-compression techniques(Springer Nature Switzerland AG, 2012) Djebbar, Fatiha; Ayad, BeghdadIn this paper, we introduce a new blind steganalysis method that can reliably detect modifications in audio signals due to steganography. Lossless data-compression ratios are computed from the testing signals and their reference versions and used as features for the classifier design. Additionally, we propose to extract additional features from different energy parts of each tested audio signal to retrieve more informative data and enhance the classifier capability. Support Vector Machine (SVM) is employed to discriminate between the cover- and the stego-audio signals. Experimental results show that our method performs very well and achieves very good detection rates of stego-audio signals produced by S-tools4, Steghide and Hide4PGP. © 2012 Springer-Verlag.Item Comparative study of digital audio steganography techniques(2012) Djebbar, Fatiha; Ayad, Beghdad; Meraim, Karim Abed; Hamam, HabibThe rapid spread in digital data usage in many real life applications have urged new and effective ways to ensure their security. Efficient secrecy can be achieved, at least in part, by implementing steganograhy techniques. Novel and versatile audio steganographic methods have been proposed. The goal of steganographic systems is to obtain secure and robust way to conceal high rate of secret data. We focus in this paper on digital audio steganography, which has emerged as a prominent source of data hiding across novel telecommunication technologies such as covered voice-over-IP, audio conferencing, etc. The multitude of steganographic criteria has led to a great diversity in these system design techniques. In this paper, we review current digital audio steganographic techniques and we evaluate their performance based on robustness, security and hiding capacity indicators. Another contribution of this paper is the provision of a robustness-based classification of steganographic models depending on their occurrence in the embedding process. A survey of major trends of audio steganography applications is also discussed in this paper. © 2012 Djebbar et al.; licensee Springer.Item Controlled distortion for high capacity data-in-speech spectrum steganography(Institute of Electrical and Electronics Engineers Inc., 2010) Djebbar, Fatiha; Hamam, Habib; Abed-Meraim, Karim; Guerchi, DrissMethods applied to ensure privacy of digital data became essential in many real life applications. Efficient secrecy can be achieved, at least in part, by implementing steganography techniques. In this paper, we present a technique that limits the impact of high data capacity embedding on the quality of stego wideband speech. Our method uses the energy of each frequency bin component to determine the maximum number of bits that can be confined without inducing any noticeable distortion on the cover speech. To guarantee good quality of stego speech, the embedding in the selected frequency components occurs below a well defined distortion level to limit the impact of the hiding on the stego-speech. The algorithm uses multiple parameters that can be adjusted by the sender to render the steganalysis work more challenging. The objective and subjective results show that this approach is robust to noise addition and maintains a very good quality of the cover signal while achieving high hiding capacity. © 2010 IEEE.Item Dynamic energy based text-in-speech spectrum hiding using speech masking properties(Institute of Electrical and Electronics Engineers Inc., 2010) Djebbar, Fatiha; Abed-Meraim, Karim; Guerchi, Driss; Hamam, HabibIn this paper we present a new method for text-in-speech Fast Fourier Transform (FFT) based steganography. Our method exploits high energetic magnitude frequency components of speech spectrum to hide the secret text. The energy level of each magnitude component is evaluated, and considered only if it is high enough to embed secret data. A frequency maskmg threshold is then calculated for each energetic frequency magnitude component to decide where to embed the secret text. As a result, the initial energy of the cover speech spectrum is slightly modified and the dIstortion error is always kept under the mask. The objective and subjective evaluations show that introducing the energy-based frequency masking 0l?ens new frontiers in text-in-speech steganography since hIgher bit rate text embedding was achieved while obtaining a stego-speech with unnoticeable distortion. © 2010 IEEE.Item Text hiding in high frequency components of speech spectrum(Institute of Electrical and Electronics Engineers Inc., 2010) Djebbar, Fatiha; Guerchi, Driss; Abed-Meraim, Karim; Hamam, HabibBoosted by recent advances in the information technology field, methods applied to ensure privacy of digital data became very important in many real life applications. Efficient secrecy can be achieved at least in part, by implementing steganograhy techniques. In this paper, we propose a new technique to hide text in wideband speech in noise free environment. We opted to work in the Fourier transform domain and hide the digital information within high frequency components. More precisely, our method exploits selected locations from the high-frequencies part of the cover speech to hide the secret text. We better preserve with high fidelity the spectrum shape of the speech carrier by employing an embedding rather than a replacement operation on the secret text. Our simulation results show that this approach maintains the robustness of the cover signal and achieves a higher hiding capacity. © 2010 IEEE.Item Unified phase and magnitude speech spectra data hiding algorithm(John Wiley and Sons Inc., 2013) Djebbar, Fatiha; Ayad, Beghdad; Abed‐Meraim, Karim; Hamam, HabibIn this paper, we present a unified algorithm for phase and magnitude speech spectra data hiding. The phase and the magnitude speech spectra are concurrently investigated to increase the capacity and the security of the embedded information. The proposed algorithm in this paper is based on finding secure spectral embedding areas in wideband magnitude speech spectrum. Our approach exploits these areas to hide data in both speech components (i.e., phase and magnitude). The embedding locations and hiding capacity are defined according to a controlled acceptable distortion in the magnitude spectrum. The latter is expressed as a set of parameters controlled by the sender. Consequently, the hiding capacity and the locations of concealed data change for each data communication instance to further prevent malicious intrusions. Objective results show that the presented algorithm in this paper secures hidden data and achieves interesting tradeoffs between the hiding capacity and the speech quality. © 2013 John Wiley & Sons, Ltd.