Since the large diffusion of digital camera and mobile devices with embedded camera and flashgun, the redeyes artifacts have de facto become a critical problem. The technique herein described makes use of three main s...
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Since the large diffusion of digital camera and mobile devices with embedded camera and flashgun, the redeyes artifacts have de facto become a critical problem. The technique herein described makes use of three main steps to identify and remove red eyes. First, red-eye candidates are extracted from the input image by using an image filtering pipeline. A set of classifiers is then learned on gray code features extracted in the clustered patches space and hence employed to distinguish between eyes and non-eyes patches. Specifically, for each cluster the gray code of the red-eyes candidate is computed and some discriminative gray code bits are selected employing a boosting approach. The selected gray code bits are used during the classification to discriminate between eye versus non-eye patches. Once red-eyes are detected, artifacts are removed through desaturation and brightness reduction. Experimental results on a large dataset of images demonstrate the effectiveness of the proposed pipeline that outperforms other existing solutions in terms of hit rates maximization, false positives reduction, and quality measure.
In Augmented Reality applications, the human perception is enhanced with computer-generated graphics. These graphics must be exactly registered to real objects in the scene and this requires an effective Augmented Rea...
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In Augmented Reality applications, the human perception is enhanced with computer-generated graphics. These graphics must be exactly registered to real objects in the scene and this requires an effective Augmented Reality system to track the user's viewpoint. In this paper, a robust tracking algorithm based on coded fiducials is presented. Square targets are identified and pose parameters are computed using a hybrid approach based on a direct method combined with the Kalman filter. An important factor for providing a robust Augmented Reality system is the correct handling of targets occlusions by real scene elements. To overcome tracking failure due to occlusions, we extend our method using an optical flow approach to track visible points and maintain virtual graphics overlaying when targets are not identified. Our proposed real-time algorithm is tested with different camera viewpoints under various image conditions and shows to be accurate and robust.
It is by now a well-known paradigm that public-key cryptosystems can be built using finite Abelian groups and that algebraic geometry provides a supply of such groups through Abelian varieties over finite fields. Of s...
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ISBN:
(数字)9781470417840
ISBN:
(纸本)9780821843116
It is by now a well-known paradigm that public-key cryptosystems can be built using finite Abelian groups and that algebraic geometry provides a supply of such groups through Abelian varieties over finite fields. Of special interest are the Abelian varieties that are Jacobians of algebraic curves. All of the articles in this volume are centered on the theme of point counting and explicit arithmetic on the Jacobians of curves over finite fields. The topics covered include Schoof's $\ell$-adic point counting algorithm, the $p$-adic algorithms of Kedlaya and Denef-Vercauteren, explicit arithmetic on the Jacobians of $C_{ab}$ curves and zeta functions.
This volume is based on seminars on algebraic curves and cryptography held at the GANITA Lab of the University of Toronto during 2001–2008. The articles are mostly suitable for independent study by graduate students who wish to enter the field, both in terms of introducing basic material as well as guiding them in the literature. The literature in cryptography seems to be growing at an exponential rate. For a new entrant into the subject, navigating through this ocean can seem quite daunting. In this volume, the reader is steered toward a discussion of a few key ideas of the subject, together with some brief guidance for further reading. It is hoped that this approach may render the subject more approachable.
Several sufficient conditions for quadratic bent func tions represented by trace are given. These sufficient conditions correspond to two families of quadratic bent functions in poly nomial forms. Furthermore, the fir...
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Several sufficient conditions for quadratic bent func tions represented by trace are given. These sufficient conditions correspond to two families of quadratic bent functions in poly nomial forms. Furthermore, the first family of bent functions includes the function proposed by Udaya and some functions proposed by Hu and Feng.
Stereo-vision is generally considered to provide information about depth in a visual scene derived from disparities in the positions of an image on the two eyes; a new study has found evidence that retinal-image codin...
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Stereo-vision is generally considered to provide information about depth in a visual scene derived from disparities in the positions of an image on the two eyes; a new study has found evidence that retinal-image coding relative to the head is also important.
The article focuses on the potential of synthetic polymer as information storage systems due to its very high density monomer sequence. It says that encoding in synthetic polymers is the same as encoding in DNAs in wh...
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The article focuses on the potential of synthetic polymer as information storage systems due to its very high density monomer sequence. It says that encoding in synthetic polymers is the same as encoding in DNAs in which information would be written and stored in the linear pattern of monomers. It refers to the research conducted by H. M. Colquhoun and colleagues which addressed the issue through the use of two complementary small-molecule tweezers which can read two different three-monomer sequences. It adds that the tweezers bind all the complementary sequences in order to recognize the code written in the polymers. Meanwhile, it discusses how polynucleotides read the ribosome in three-nucleotide sequences, which are called as codons, in a way similar to the said tweezers.
A new angular discretization scheme based on the Daubechies' wavelets has been developed in recent studies. A decoupled S-N and wavelet expansion method was proposed. This paper discusses the limitations and impro...
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A new angular discretization scheme based on the Daubechies' wavelets has been developed in recent studies. A decoupled S-N and wavelet expansion method was proposed. This paper discusses the limitations and improvements of this decoupled scheme. The scaling function, instead of the wavelet function, is applied as the basis function. It significantly improved the efficiency and computational stability. A new series of wavelets on the interval are applied instead of the 'wrapped wavelets', which eliminate the edge effect in the angular subdomain scheme. Based on the improvements, a wavelet-based neutron transport code package WAVTRAN is developed and the previous work is extended to the three-dimensional calculation and anisotropic scattering calculation. Numerical results demonstrate that the improvements are effective. Further investigations demonstrate that the wavelet-based angular discretization scheme is more powerful than the traditional ones in some highly anisotropic angular flux problems. (C) 2009 Elsevier Ltd. All rights reserved.
A novel matching pursuit (MP) image coding method is presented. A block partitioning scheme is employed to effectively exploit the spatial characteristics of MP atoms. Experimental results show that the proposed metho...
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A novel matching pursuit (MP) image coding method is presented. A block partitioning scheme is employed to effectively exploit the spatial characteristics of MP atoms. Experimental results show that the proposed method significantly outperforms the existing MP coding methods and thus bridges the gap in coding efficiency between MP- and wavelet-based approaches.
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