In this paper, a novel DWT-SVD perceptual fidelity metric for the evaluation of watermarking schemes is introduced. The proposed metric is based on a widely used Human Visual Model in the Discrete Wavelet Transform do...
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In this paper, a novel DWT-SVD perceptual fidelity metric for the evaluation of watermarking schemes is introduced. The proposed metric is based on a widely used Human Visual Model in the Discrete Wavelet Transform domain accounting for the frequency sensitivity, and the local luminance and contrast masking effects of the human eye. A relationship between the visual model in the DWT domain and the modification of the wavelet coefficients's singular values is derived. The proposed metric is validated through subjective assessment and its performance is compared to several state-of-the-art perceptual image distortion metrics. The paper focus on Image Adaptive Watermarking methods in the Discrete Wavelet Transform Domain since they yield better results regarding robustness and transparency than other watermarking schemes.
In computer vision, the animation of objects has attracted a lot of attention, specially the animations of 3D face models. The animation of face models requires in general to manually adapt each generic movement (open...
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In computer vision, the animation of objects has attracted a lot of attention, specially the animations of 3D face models. The animation of face models requires in general to manually adapt each generic movement (open/close mouth) to each specific head geometry. In this work we propose a technique for the animation of any face model avoiding most of the manual intervention. In order to achieve this we assume that: (1) faces, despite obvious differences are quite similar and a single generic model can be used to simplify deformations and (2) using this face model, a simple interpolation technique can be used, with minimal manual intervention. Several examples are presented to verify the realism of the obtained animations.
In computer vision, the animation of objects has attracted a lot of attention, specially the animations of 3D face models. The animation of face models requires in general to manually adapt each generic movement (open...
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When developing a cDNA microarray experiment, the segmentation of individual spots is a crucial stage. Spot intensity measurements and gene expression ratios directly depend on the effectiveness and accuracy of the se...
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A subspace based approach for the blind identification/equalization of nonlinear Single Input Multiple Output (SIMO) time-invariant channels is presented in this paper. The considered models include, but are not limit...
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A subspace based approach for the blind identification/equalization of nonlinear Single Input Multiple Output (SIMO) time-invariant channels is presented in this paper. The considered models include, but are not limit...
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A subspace based approach for the blind identification/equalization of nonlinear Single Input Multiple Output (SIMO) time-invariant channels is presented in this paper. The considered models include, but are not limited to, polynomial approximations of nonlinear channels (i.e., Volterra models), which have been used to represent satellite communications, magnetic recording channels, and physiological processes, among other applications. The channel parameters are estimated in closed form, up to a scalar factor, by computing the column space of the output Hankel matrix, via a Singular Value Decomposition (SVD), and then solving a Least Squares (LS) estimation problem also resorting to an SVD. Numerical simulations are used to illustrate the performance of the proposed algorithms.
In this paper, the performance of several state-of-the-art watermark perceptual transparency metrics is evaluated through subjective assessment. Simulation results show that a metric based on S-CIELAB distortion maps ...
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ISBN:
(纸本)9789898111609
In this paper, the performance of several state-of-the-art watermark perceptual transparency metrics is evaluated through subjective assessment. Simulation results show that a metric based on S-CIELAB distortion maps proved to be better correlated to the subjective tests than other objective metrics available in the literature. The paper focus on Image Adaptive Watermarking methods in the Discrete Wavelet Transform Domain since they yield better results regarding robustness and transparency than other watermarking schemes.
An Image Adaptive Watermarking method based on the Discrete Wavelet Transform is presented in this paper. The robustness and fidelity of the proposed method are evaluated and the method is compared to state-of-the-art...
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An Image Adaptive Watermarking method based on the Discrete Wavelet Transform is presented in this paper. The robustness and fidelity of the proposed method are evaluated and the method is compared to state-of-the-art watermarking techniques available in the literature. For the evaluation of watermark transparency, an image fidelity factor based on a perceptual distortion metric is introduced. This new metric allows a perceptually aware objective quantification of image fidelity.
Algorithms for facial motion tracking and animation of avatars based on video sequences of a real person are presented in this paper. The tracking algorithm is based on image processing techniques and Independent Comp...
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Algorithms for facial motion tracking and animation of avatars based on video sequences of a real person are presented in this paper. The tracking algorithm is based on image processing techniques and Independent Comp...
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Algorithms for facial motion tracking and animation of avatars based on video sequences of a real person are presented in this paper. The tracking algorithm is based on image processing techniques and Independent Component Analysis (ICA), while the animation algorithm is based on Facial Animation Parameters of the MPEG-4 standard. Simulation results illustrating the performance of the proposed algorithms are also included in this paper.
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