Mohammad K. Ibrahim

Digital image watermarking using balanced multiwavelets

In this paper, a robust watermarking algorithm using balanced multiwavelet transform is proposed. The latter transform achieves simultaneous orthogonality and symmetry without requiring any input prefiltering. Therefore, considerable reduction in computational complexity is possible, making this transform a good candidate for real-time watermarking implementations such as audio broadcast monitoring and DVD video watermarking. The embedding scheme is image adaptive using a modified version of a well-established perceptual model. Therefore, the strength of the embedded watermark is controlled according to the local properties of the host image. This has been achieved by the proposed perceptual model, which is only dependent on the image activity and is not dependent on the multifilter sets used, unlike those developed for scalar wavelets. This adaptivity is a key factor for achieving the imperceptibility requirement often encountered in watermarking applications. In addition, the watermark embedding scheme is based on the principles of spread-spectrum communications to achieve higher watermark robustness. The optimal bounds for the embedding capacity are derived using a statistical model for balanced multiwavelet coefficients of the host image. The statistical model is based on a generalized Gaussian distribution. Limits of data hiding capacity clearly show that balanced multiwavelets provide higher watermarking rates. This increase could also be exploited as a side channel for embedding watermark synchronization recovery data. Finally, the analytical expressions are contrasted with experimental results where the robustness of the proposed watermarking system is evaluated against standard watermarking attacks.

Orthogonal Wavelet Division Multiplex: An Alternative to OFDM

Over the past three decades, the scientific and industrial communities have injected considerable resources into perfecting orthogonal frequency division multiplex (OFDM) - the driving technology behind many applications used today (such as IEEE 802.11g, asymmetric digital subscriber line (ADSL), and digital terrestrial television). In 1997, OFDM was officially sanctioned for use in the European Telecommunications Standards Institute (ETSI) EN 300 744 standard known as digital video broadcasting-terrestrial (DVB-T). As OFDM is such a popular technology, there has been limited research over the years into alternatives. This paper proposes a novel approach to transmit parallel information through a terrestrial channel that could render it a more flexible alternative to OFDM in the future. Investigations have shown that this technique could provide a highly flexible, channel optimized modulation technique based on time-frequency multiplexing and this paper presents the preliminary phase of investigations into this new technique .

High radix parallel architecture for GF(p) elliptic curve processor

A new GF(p) cryptographic processor architecture for elliptic curve encryption/decryption is proposed in this paper. The architecture takes advantage of projective coordinates to convert GF(p) inversion needed in elliptic point operations into several multiplication steps. Unlike existing sequential designs, we show that projecting into (X/Z,Y/Z) leads to a much better performance than the conventional choice of projecting into the current (X/Z/sup 2/,Y/Z/sup 3/). We also propose to use high radix modulo multipliers which give a wide range of area-time trade-offs. The proposed architecture is a significant challenger for implementing data security systems based on elliptic curve cryptography.

Bit-level pipelined digit serial GF(2/sup m/) multiplier

A low latency digit serial multiplier for GF(2/sup m/) that can be pipelined to the bit-level is presented in this paper. Unlike existing structures, the new multiplier does not put any restriction on the type of generator polynomial used or the digit size. Furthermore, the latency of the new multiplier is significantly less than the latency of the existing bit-level pipelined digit-serial multiplier.

Generic-point parallel scalar multiplication without precomputations.

The first efficient generic-point parallel scalar multiplication method is presented here. The novelty of the proposed method is that the precomputation overhead can be replaced by postcomputations that can be parallelised. This method will be very attractive for use in high-performance end servers that employ parallel elliptic curve cryptoprocessors.

Power-time flexible architecture for GF(2 k ) elliptic curve cryptosystem computation

New elliptic curve cryptographic processor architecture is presented that result in considerable reduction in power consumption as well as giving a range of trade-off between speed and power consumption. This is achieved by exploiting the inherent parallelism that exist in elliptic curve point addition and doubling. Further trade-off is achieved by using digit serial-parallel multipliers instead of the serial-serial multipliers used in conventional architectures. In effect, the new architecture exploits parallelism at the algorithm level as well as at the arithmetic element level. This parallelism can be exploited either to increase the speed of operation or to reduce power consumption by reducing the frequency of operation and hence the supply voltage.

Parallelizing GF(P) elliptic curve cryptography computations for security and speed

The elliptic curve cryptography can be observed as two levels of computations, upper scalar multiplication level and lower point operations level. We combine the inherited parallelism in both levels to reduce the delay and improve security against the simple power attack. The best security and speed performance is achieved when parallelizing the computation to eight parallel multiplication operations. This strategy is worth considering since it shows very attractive performance conclusions.

Image compression using texture modeling

We consider the problem of improving the performance of multiwavelets-based image coders through texture parametrization. Texture parametrization is designed to achieve higher compression rates while maintaining excellent visual image quality. Tradeoffs among these two conflicting goals, maximizing compression rate and minimizing distortion due to compression, are possible by taking into account the imperfections inherent in the human visual system (HVS). We present a statistical view of the texture parametrization using balanced multiwavelets and develop a hybrid image compression scheme. The statistical scheme leads to a new multiresolution-based texture parametrization relying on the accurate modeling of the marginal distribution of balanced multiwavelet coefficients using generalized Gaussian density (GGD). Furthermore, we show that the proposed texture parametrization scheme is computationally-efficient. The proposed hybrid codec can be seamlessly integrated in any embedded image coder while requiring minimal header data.

High performance elliptic curve GF(2/sup k/) cryptoprocessor architecture for multimedia

A high performance GF(2/sup k/) elliptic curve crypto processor architecture suitable for multimedia security is proposed. To meet the high data rates of multimedia, the new architecture exploits parallelism within elliptic curve point operations after using projective coordinates. In this paper, the decision on which projective coordinate to use is based on its efficiency with regard to its parallel implementation. Two different projective coordinates are compared here. This parallelism is exploited in the new architecture by using three separate bit-level pipelined digit serial-parallel multipliers that can operate in parallel. It is worth pointing that such multipliers are ideally suited for the repetitive multiplications inherent in elliptic curve cryptography. it is believed that such high performance architectures are needed for high end servers that need to support the security of many multimedia streams at the same time.

A Generic Architectural Framework for Proactive Systems Inspired by Molecular Biology

A generic framework for the development of proactive systems inspired by molecular biology systems is presented in this paper. Proactive systems need to predict future concerns and not only finding solutions to problems as is the case with conventional systems. The framework is also generic enough to represent human behaviour in general. It is also applicable to conventional systems. The main feature of the proposed framework is that allows the incorporation of all possible frameworks and findings about a subject matter into one fused framework.