Habib Hamam

Comparative study of digital audio steganography techniques

The 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.

A view on latest audio steganography techniques

Steganography has been proposed as a new alternative technique to enforce data security. Lately, novel and versatile audio steganographic methods have been proposed. A perfect audio Steganographic technique aim at embedding data in an imperceptible, robust and secure way and then extracting it by authorized people. Hence, up to date the main challenge in digital audio steganography is to obtain robust high capacity steganographic systems. Leaning towards designing a system that ensures high capacity or robustness and security of embedded data has led to great diversity in the existing steganographic techniques. In this paper, we present a current state of art literature in digital audio steganographic techniques. We explore their potentials and limitations to ensure secure communication. A comparison and an evaluation for the reviewed techniques is also presented in this paper.

A new approach for optical colored image compression using the JPEG standards

Image compression consists in reducing information volume representing an image. Elimination of redundancies and non-pertinent information enables memory space minimization and thus faster data transmission. The present work aims to improve the quality of the compressed image while minimizing the time required for compression by using the principle of coherent optics. We present an optical adaptation of the method of JPEG compression technique for binary, gray-level and color images. Illustrative simulations will be given at the end to validate our architecture and to evaluate the performance on different types of images (binary, gray and color). An optical implementation setup is proposed and validated experimentally.

Speech steganography using wavelet and Fourier transforms

A new method to secure speech communication using the discrete wavelet transforms (DWT) and the fast Fourier transform is presented in this article. In the first phase of the hiding technique, we separate the speech high-frequency components from the low-frequency components using the DWT. In a second phase, we exploit the low-pass spectral proprieties of the speech spectrum to hide another secret speech signal in the low-amplitude high-frequency regions of the cover speech signal. The proposed method allows hiding a large amount of secret information while rendering the steganalysis more complex. Experimental results prove the efficiency of the proposed hiding technique since the stego signals are perceptually indistinguishable from the equivalent cover signal, while being able to recover the secret speech message with slight degradation in the quality.

Fuzzy Clustering with Improved Artificial Fish Swarm Algorithm

This paper applies the artificial fish swarm algorithm (AFSA) to fuzzy clustering. An improved AFSA with adaptive Visual and adaptive step is proposed. AFSA enhances the performance of the fuzzy C-Means (FCM) algorithm. A computational experiment shows that AFSA improved FCM out performs both the conventional FCM algorithm and the Genetic Algorithm (GA) improved FCM.

Segmented phase-only filter binarized with a new error diffusion approach

The use of segmented phase-only filters improves the performance of optical correlators. In contrast to conventional filters that compare the scene image to a single reference, a multidecision correlator undertakes several decisions by integrating information from several references into a single segmented phase-only filter. In practice, the optical implementation of such a filter in a multidecision correlator requires the use of optoelectronic interfaces like binary EASLMs. Despite the very high speed of reconfigurability offered by these elements, binarization limits their performance. By straightforwardly applying the constraint of binarization on the segmented filter, the resulting quantization noise significantly reduces the correlator performance. In the present work a new method for diffusing quantization errors is proposed to optimize the binarization process in a way adapted to our application.

A Policy Based Event Management Middleware for Implementing RFID Applications

Radio Frequency Identification (RFID) has become a popular identification technology in a number of application areas such as supply chain management. A dedicated middleware solution is required to achieve the maximum benefits of RFID technology. The middleware components serve to abstract the communication between the middleware and the different types of sensing devices on one hand, and the middleware and backend applications on the other hand. FlexRFID is a simple and smart RFID middleware which provides device management and monitoring, data processing, filtering, and aggregation, rapid application development, as well as a policy based business rules layer which helps applying rules for accessing and configuring the services provided by the middleware. This layer serves to process some business intelligence rules locally so that the host system is offloaded from those mundane tasks. The paper shows that FlexRFID is a highly scalable and easily deployable middleware in the heterogeneous sites based on different standards and consisting of different hardware. Apart from these, FlexRFID incorporates the mechanisms for supervision, testing, and control of its components, plus handles the security and privacy issues that inhibit the adoption of RFID technology by applying the privacy policies in the business rules layer. FlexRFID middleware is controlling the data flows in and out as well as locally controlling some intelligence.

FlexRFID: A flexible middleware for RFID applications development

Nowadays, Radio Frequency Identification (RFID) is a popular automatic wireless identification technology, and provides promising benefits in a number of application areas such as supply chain management. Though RFID technology has attracted a significant attention due to the convergence of lower cost and increased hardware capabilities, there still exist major hurdles for the practical realization of its benefits. To achieve the maximum benefits of RFID technology, a dedicated middleware solution is required for managing and monitoring RFID readers or other types of sensing devices, as well as processing dynamically generated high volumes of noisy RFID data. Apart from these, such middleware should possess useful contextual characteristics such as implicit semantics, and support rapid RFID based application development. FlexRFID as reported in this paper is a simple and smart RFID middleware which satisfies the requirements mentioned earlier. The paper shows that FlexRFID is a highly scalable and easily deployable middleware in the heterogeneous sites based on different standards and consisting of different hardware. Apart from these, FlexRFID incorporates the mechanisms for supervision, testing, and control of its components, plus handles the security and privacy issues that inhibit the adoption of RFID technology.

Unified phase and magnitude speech spectra data hiding algorithm

In 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. Copyright

RoF Networks : A comprehensive study

We present a comparative study of different Fiber-Wireless networks with regards to their applications, architecture, hardware complexity, development costs, offered services and allocated bandwidths. While spectral resources and high data-rates are incessantly requested, these radio over fiber (RoF) networks have been proposed to overcome limitation in bandwidth. They take advantage of the spectral potential of millimeter-waves bands. Due to their flexibility, RoF links may be designed for a transparent transport of analog or digital signals. Several applications, based on point to point or point to multi points links, are here reviewed. Trends and prospects for these networks are also explored.