With the rapid development of multi-view video coding (MVC) and light field rendering (LFR), Free-View Television (FTV) has emerged as new entrainment equipment, which can bring more immersive and realistic feelings for TV viewers. In FTV broadcasting system, the TV-viewer can freely watch a realistic arbitrary view of a scene generated from a number of original views. In such a scenario, the ownership of the multi-view video should be verified not only on the original views, but also on any virtual view. However, capacities of existing watermarking schemes as copyright protection methods for LFR-based FTV are only one bit, i.e., presence or absence of the watermark, which seriously impacts its usage in practical scenarios. In this paper, we propose a robust multi-bit watermarking scheme for LFR-based free-view video. The direct-sequence code division multiple access (DS-CDMA) watermark is constructed according to the multi-bit message and embedded into DCT domain of each view frame. The message can be extracted bit-by-bit from a virtual frame generated at an arbitrary view-point with a correlation detector. Furthermore, we mathematically prove that the watermark can be detected from any virtual view. Experimental results also show that the watermark in FTV can be successfully detected from a virtual view. Moreover, the proposed watermark method is robust against common signal processing attacks, such as Gaussian filtering, salt & peppers noising, JPEG compression, and center cropping.

Deposition of inclined anisotropy film for bit-patterned media was studied using an oblique incidence collimated sputtering. Pt underlayer increased the inclination angle of magnetic layer more than 5° on a Ta seed layer. Further increase of the angle was obtained by annealing Pt/Ru underlayer resulting an inclination angle of 9.4° for a Co-Cr15.5 film on the underlayer. The magnetic properties of the Co-Cr15.5 film with an inclined orientation was estimated comparing measured hysteresis loops with simulated ones, which indicated to have inclined magnetic anisotropy with an anisotropy field of about 4.5kOe and a deflection angle of the anisotropy about the same as that of the crystalline orientation.

With the diffusion of web services caused by the appearance of a new architecture known as cloud computing, a large number of websites have been used by attackers as hopping sites to attack other websites and user terminals because many vulnerable websites are constructed and managed by unskilled users. To construct hopping sites, many attackers force victims to download malware by using vulnerabilities in web applications. To protect websites from these malware infection attacks, conventional methods, such as using anti-virus software, filter files from attackers using pattern files generated by analyzing conventional malware files collected by security vendors. In addition, certain anti-virus software uses a behavior blocking approach, which monitors malicious file activities and modifications. These methods can detect malware files that are already known. However, it is difficult to detect malware that is different from known malware. It is also difficult to define malware since legitimate software files can become malicious depending on the situation. We previously proposed an access filtering method based on communication opponents, which are other servers or terminals that connect with our web honeypots, of attacks collected by web honeypots, which collect malware infection attacks to websites by using actual vulnerable web applications. In this blacklist-based method, URLs or IP addresses, which are used in malware infection attacks collected by web honeypots, are listed in a blacklist, and accesses to and from websites are filtered based on the blacklist. To reveal the effects in an actual attack situation on the Internet, we evaluated the detection ratio of anti-virus software, our method, and a composite of both methods. Our evaluation revealed that anti-virus software detected approximately 50% of malware files, our method detected approximately 98% of attacks, and the composite of the two methods could detect approximately 99% of attacks.

In this study, the influence of Gd composition on current-induced domain wall motion in a Gd-Co ferrimagnetic nanowire was theoretically investigated with taking into account of composition dependence of magnetic properties. As a result, the intrinsic critical density to move domain wall significantly reduces near the compensation composition, which is achieved to be less than 105A/cm2. Moreover, the intrinsic critical current density also significantly reduces near a certain Gd composition where the domain wall energies of Bloch and Néel walls are almost the same.

This paper proposes an improved color barycenter model (CBM) and its separation for automatic road sign (RS) detection. The previous version of CBM can find out the colors of RS, but the accuracy is not high enough for separating the magenta and blue regions and the influence of number with the same color are not considered. In this paper, the improved CBM expands the barycenter distribution to cylindrical coordinate system (CCS) and takes the number of colors at each position into account for clustering. Under this distribution, the color information can be represented more clearly for analyzing. Then aim to the characteristic of barycenter distribution in CBM (CBM-BD), a constrained clustering method is presented to cluster the CBM-BD in CCS. Although the proposed clustering method looks like conventional K-means in some part, it can solve some limitations of K-means in our research. The experimental results show that the proposed method is able to detect RS with high robustness.

The recursive transfer method (RTM) is a numerical technique that was developed to analyze scattering phenomena and its formulation is constructed with a difference equation derived from a differential equation by Numerov's discretization method. However, the differential equation to which Numerov's method is applicable is restricted and therefore the application range of RTM is also limited. In this paper, we provide a new discretization scheme to extend RTM formulation using the weak form theory framework. The effectiveness of the proposed formulation is confirmed by microwave scattering induced by a metallic pillar placed asymmetrically in the waveguide. A notable feature of RTM is that it can extract a localized wave from scattering waves even if the tail of the localized wave reaches to the ends of analyzing region. The discrepancy between the experimental and theoretical data is suppressed with in an upper bound determined by the standing wave ratio of the waveguide.

In information retrieval from printed images considering the use of mobile devices, the correction of geometrical deformation and lens distortion is required, posing a heavy computational burden. In this paper, we propose a method of reducing the computational burden for such corrections. This method consists of improved extraction to find a line segment of a frame, the reconsideration of the interpolation method for image correction, and the optimization of image resolution in the correction process. The proposed method can reduce the number of computations significantly. The experimental result shows the effectiveness of the proposed method.

This letter proposes a novel depth-guided inpainting scheme for the high quality hole-filling in 2D-to-3D video conversion. The proposed scheme detects and removes foreground depth layers in an image patch, enabling appropriate patch formation using only disoccluded background information. This background only patch formation helps to avoid the propagation of wrong depths over hole area, and thus improve the overall quality of converted 3D video experience. Experimental results demonstrate the proposed scheme provides visually much more pleasing inpainting results with better preserved object edges compared to the state-of-the-art depth-guided inpainting schemes.

In secret sharing scheme, Tompa and Woll considered a problem of cheaters who try to make another participant reconstruct an invalid secret. Later, some models of such cheating were formalized and lower bounds of the size of shares were shown in the situation of fixing the minimum successful cheating probability. Under the assumption that cheaters do not know the distributed secret, no efficient scheme is known which can distribute bit strings. In this paper, we propose an efficient scheme for distributing bit strings with an arbitrary access structure. When distributing a random bit string with threshold access structures, the bit length of shares in the proposed scheme is only a few bits longer than the lower bound.

The abundance of information published on the Internet makes filtering of hazardous Web pages a difficult yet important task. Supervised learning methods such as Support Vector Machines (SVMs) can be used to identify hazardous Web content. However, scalability is a big challenge, especially if we have to train multiple classifiers, since different policies exist on what kind of information is hazardous. We therefore propose two different strategies to train multiple SVMs for personalized Web content filters. The first strategy identifies common data clusters and then performs optimization on these clusters in order to obtain good initial solutions for individual problems. This initialization shortens the path to the optimal solutions and reduces the training time on individual training sets. The second approach is to train all SVMs simultaneously. We introduce an SMO-based kernel-biased heuristic that balances the reduction rate of individual objective functions and the computational cost of kernel matrix. The heuristic primarily relies on the optimality conditions of all optimization problems and secondly on the pre-calculated part of the whole kernel matrix. This strategy increases the amount of information sharing among learning tasks, thus reduces the number of kernel calculation and training time. In our experiments on inconsistently labeled training examples, both strategies were able to predict hazardous Web pages accurately (> 91%) with a training time of only 26% and 18% compared to that of the normal sequential training.

Electromagnetic scattering and radiation in cylindrical electromagnetic bandgap (EBG) structure is analyzed. The radiated field from a line source placed inside the eccentric configuration of the cylindrical EBG structure and plane wave incident on the cylindrical EBG structure is numerically studied based on the method proposed by the authors in their early papers. Using the developed formulation, it is shown first time that when the cylindrical EBG is illuminated by plane wave of particular resonance frequencies, the field are strongly enhanced or shaded inside the cylindrical EBG structure and this effect depends on the angle of incidence of the plane waves. We give a deep physical insight into explanation of this phenomenon based on the Lorentz reciprocity relation for cylindrical structures.

This paper proposes a secure wireless network system required for an ambient information society; it forms a privacy zone wherein terminals can securely communicate secret information using an arbitrary general radio channel. For this system, we introduce a scheme using a side-information from a special node. The information is used as an encryption key so that the detectable region of the key defines a privacy zone. We implement the scheme on the basis of IEEE 802.15.4 and realize the world's first ambient network platform with the above functionality. An experiment and demonstration show the effectiveness of the proposed system.

Phase-nonreciprocal ε-negative and CRLH metamaterials are analyzed using a new approach in which field analysis and transmission line model are combined. The examined one-dimensional nonreciprocal metamaterials are composed of a ferrite-embedded microstrip line periodically loaded with shunt stubs. In the present approach, the phase constant nonreciprocity is analytically estimated and formulated under the assumption of operating frequency far above the ferromagnetic resonant frequency. The present approach gives a good explanation to the phenomenon in terms of ferromagnetic properties of the ferrite and asymmetric geometry of the metamaterial structure, showing a good agreement with numerical simulations and experiment.

Digital watermarking techniques have been used to assert the ownerships of digital images. The ownership information is embedded in an image as a watermark so that the owner of the image can be identified. However, many types of attacks have been used in attempts to break or remove embedded watermarks. Therefore, the watermark should be very robust against various kinds of attacks. Among them, the print-and-scan (PS) attack is very challenging because it not only alters the pixel values but also changes the positions of the original pixels. In this paper, we propose a watermarking system operating in the discrete cosine transform (DCT) domain. The polarities of the DCT coefficients are modified for watermark embedding. This is done by considering the properties of DCT coefficients under the PS attack. The proposed system is able to maintain the image quality after watermarking and the embedded watermark is very robust against the PS attack as well.

Electromagnetic power transmission through two cyl-inder-penetrated circular apertures in parallel conducting planes is studied. The Weber transform and superposition principle are used to represent the scattered field. A set of simultaneous equations for the modal coefficients are constituted based on the mode-matching and boundary conditions. The whole integration path is slightly deformed into a new one below the positive real axis not to pass through the pole singularities encountered on the original path so that it is easily calculated by direct numerical quadrature. Computation shows the behaviors of power transmission in terms of aperture geometry and wavelength. The presented scheme is very amenable to numerical evaluations and useful for various electromagnetic scattering and antenna radiation analysis involved with singularity problems.

Mutual information (MI) is a standard measure of statistical dependence of random variables. However, due to the log function and the ratio of probability densities included in MI, it is sensitive to outliers. On the other hand, the L2-distance variant of MI called quadratic MI (QMI) tends to be robust against outliers because QMI is just the integral of the squared difference between the joint density and the product of marginals. In this paper, we propose a kernel least-squares QMI estimator called least-squares QMI (LSQMI) that directly estimates the density difference without estimating each density. A notable advantage of LSQMI is that its solution can be analytically and efficiently computed just by solving a system of linear equations. We then apply LSQMI to dependence-maximization clustering, and demonstrate its usefulness experimentally.

A directional lapped orthogonal transform (DirLOT) is an orthonormal transform of which basis is allowed to be anisotropic with the symmetric, real-valued and compact-support property. Due to its directional property, DirLOT is superior to the existing separable transforms such as DCT and DWT in expressing diagonal edges and textures. The goal of this paper is to enhance the ability of DirLOT further. To achieve this goal, we propose a novel image restoration technique using multiple DirLOTs. This paper generalizes an image denoising technique in [1], and expands the application of multiple DirLOTs by introducing linear degradation operator P. The idea is to use multiple DirLOTs to construct a redundant dictionary. More precisely, the redundant dictionary is constructed as a union of symmetric orthonormal discrete wavelet transforms generated by DirLOTs. To select atoms fitting a target image from the dictionary, we formulate an image restoration problem as an l1-regularized least square problem, which can efficiently be solved by the iterative-shrinkage/thresholding algorithm (ISTA). The proposed technique is beneficial in expressing multiple directions of edges/textures. Simulation results show that the proposed technique significantly outperforms the non-subsampled Haar wavelet transform for deblurring, super-resolution, and inpainting.

The optimal design of an extrapolated impulse response (EIR) filter (in the mini-max sense) is a non-linear programming problem. In this paper, the optimal design of the EIR filter by the semi-infinite programming (SIP) is investigated and an iterative technique for optimally designing the EIR filter is proposed. The simulation experiment validates the effectiveness of the SIP technique and the proposed iterative technique in the optimal design of the EIR filter.

Metamaterials are generally defined as a class of artificial effective media which macroscopically exhibit extraordinary electromagnetic properties that may not be found in nature, and are composed of periodically structured dielectric, or magnetic, or metallic materials. This paper reviews recently developed electromagnetic modeling methods of metamatericals and their inherent basic ideas, with a focus on full wave numerical techniques. Methods described in this paper are the Method of Moments (MoM) and the Finite Difference Time Domain (FDTD) Method for scattering problems excited by an incident plane wave and a single nonperiodic source, and the Finite Element Method (FEM), the Finite Difference Frequency Domain (FDFD) method and the FDTD method for band diagram calculations.

This paper describes a robust three-dimensional (3D) surface reconstruction method that can automatically eliminate shadowing errors. For modeling shadowing effect, a new shadowing compensation model based on the angle distribution of backscattered electrons is introduced. Further, it is modified with respect to some practical factors. Moreover, the proposed iterative shadowing compensation method, which performs commutatively between the compensation of image intensities and the modification of the corresponding 3D surface, can effectively provide both an accurate 3D surface and compensated shadowless images after convergence.