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With advances in sensor technology, three dimensional (3D) face has become an emerging biometric modality, preferred especially in high security applications. However, dealing with facial occlusions is a great challenge, which should be handled to enable applicability to fully automatic security systems. In this paper, we propose a technique to deal with occlusions at the classification stage: A masking...
In this study, the effect of using regression on sentiment classification of Twitter data was analyzed. In other words, whether the strength of sentiment better discriminates the classes or not. Since our dataset includes class confidence scores rather than discrete class labels, regression analysis was employed on each class separately. Then, each tweet was assigned the class whose estimated confidence...
Wave propagation in high frequency (HF) band gives the opportunity of reliable and robust long distance communication. HF communication is provided as a result of refraction and reflection of sky wave in the ionosphere. The structure of the ionosphere is time dependent, inhomogeneous and anisotropic. Modeling of the ionosphere and wave propagation in the ionosphere properly is very important for HF...
Detection and analysis of tables on document images has been one of the most researched topics in document image processing. In this study, we define novel methods for the detection and analysis of tables from document images, and show their performance results on realistic table examples. The main method developed is projection-scale-space (PSS), where local and global constraints of the table in...
Compressive Sensing (CS) theory details how a sparsely represented signal in a known basis can be reconstructed using less number of measurements. In many practical systems, the observation signal has a sparse representation in a continuous parameter space. This situation rises the possibility of use of the CS reconstruction techniques in the practical problems. In order to utilize CS techniques,...
Checking authentication of digital images have become a necessity due to ever increasing use in many fields. Passive methods, which make use of image statistics, have gained popularity among researchers lately. Block based authentication methods using feature vectors of subblocks in images can be classified as either spatial or frequency domain. A new hybrid authentication technique is proposed in...
This paper proposes a method to establish joint ownership of digital images by embedding imperceptible digital pattern in the image. This digital pattern is generated from biometric features of more than one subject in a strategic matter so that the identification of individual subject can be done and the multiple ownership of the digital images can be established. This digital pattern was embedded...
In this study, we proposed a method of hiding the stego image in cover image by using a technique called fractional fourier transform with wavelet coefficients. Application of steganography is internet/web security. To maintain higher security Arnold transform is performed on host image with key, key is only known to a receiver/sender. For embedding, perform a fractional Fourier transform of cover...
The existing digital watermarking schemes use a digital pattern like pseudorandom number sequence, a logo image or a digital signature as the watermark. Use of such watermarks is not convincing as the ownership of such a watermark is not clear for ownership claims. This paper proposes an efficient digital watermark generation technique from biometric iris data which will be unique and can be owned...
Audio data hiding techniques have been applied various applications such as audio watermarking and steganography. In this paper, we propose an audio data hiding method based on the phase information of the modulated complex lapped transform (MCLT) coefficients and evaluate the performance in terms of audio quality and robustness. To embed and extract the data, the proposed technique modifies the phases...
This paper introduces a new set of 2D transforms, called Quaternion Radial Tchebichef Moments (QRTMs), in color image watermarking. The proposed scheme constitutes the first attempt in moment-based color image watermarking. The watermark logo information is iteratively embedded enhancing its integrity with the application of the majority-vote decision rule in the detector side. Scheme's robustness...
The main objective of developing an image watermarking technique is to satisfy both imperceptibility and robustness requirements. To achieve this objective, a hybrid image watermarking scheme based on discrete wavelet transform and singular value decomposition is proposed in this paper. In our approach, the edge information of an image is used to embed the watermark. In addition, we apply the particle...
This document presents a survey on reported devices exploiting the emerging technology of self-mixing interferometry for non-contact displacement reconstruction. Nowadays, there is a broad diversity of signal processing methods over self-mixing devices, making difficult to decide which one would satisfy a given application domain. It has been observed that a change in the requirements specification...
In this paper, we present and investigate a method to attack and remove multimedia steganography in digital audio data. Among the existing steganography methods that can be used to hide secret data in digital audio carriers, the Spread Spectrum methods are among the most effective and robust for embedding steganography data. Though there are currently a few research efforts on removing or destroying...
Developing a watermarking method that is robust to cropping attack is a challenging task in image watermarking. The moment-based watermarking schemes show good robustness to common signal processing attacks and some geometric attacks but are sensitive to cropping attack. In this paper, we modify the moment-based approach to deal with cropping attack. Firstly, we find the probability density function...
A new audio watermarking algorithm based on wavelet domain transformation is being presented in this paper. The proposed algorithm follows embedding and extraction processes. In the embedding procedure, the audio signal is divided into non overlapping frames and then each frame is decomposed into 3-level wavelet transform using 4-coefficient daubechies wavelet (db4) filter. Then after using a quantization...
In order to employ powerful tools in signal processing to analyze symbolic sequences, a mapping is commonly applied first to transform the symbolic sequences to numerical sequences. Therefore it is important to investigate the role of the mapping in the final analysis results. The concepts of mapping equivalence and related theory have been proposed previously for the case where the data is processed...
The conventional linear minimum mean square error estimator (LMMSE) suffers a severe performance degradation whenever the sample size is comparable to the observation dimension. In order to tackle this problem, we propose an optimal linear correction of the conventional LMMSE, which minimizes the average mean square error (MSE) by using the moments of the complex inverse Wishart distribution. Numerical...
A robust and geometric invariant digital image watermarking scheme based on robust feature points detector and local Zernike transform is proposed in this paper. The robust feature points detector is proposed based on SIFT algorithm to extract circular patches. A local Zernike moments-based watermarking scheme is raised. Each extracted circular patch is decomposed into a collection of binary patches...
This paper addresses the problem of controller design for 2-D singular Roesser models. Sufficient stability conditions are formulated in terms of strict linear matrix inequalities (LMIs) for 2-D singular systems described by the Roesser models. Then a set of sufficient conditions for existence of desired a state feedback controller are obtained. Numerical example is provided to demonstrate the effectiveness...
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