this paper introduces a new connected filter which provides image simplification in terms of flat zone and graylevel reduction. this filtering consists in application of morphological operators to the histogram. It is...
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ISBN:
(纸本)0769513301
this paper introduces a new connected filter which provides image simplification in terms of flat zone and graylevel reduction. this filtering consists in application of morphological operators to the histogram. It is done because each object in the image has a significative distribution of graylevels in the histogram. In other words, that is enough to classify the distributions in the histogram for simplification of that objects. It is also shown some experimental results, where the proposed method is compared to other classical ones applied to flat zone and graylevel reduction.
In this paper, we present a multi-threaded sort-first distributed rendering system. In order to achieve load balance among the rendering nodes, we propose a new partitioning scheme based on the rendering time of the p...
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ISBN:
(纸本)0769522270
In this paper, we present a multi-threaded sort-first distributed rendering system. In order to achieve load balance among the rendering nodes, we propose a new partitioning scheme based on the rendering time of the previous frame. the proposed load-balancing algorithm is very simple to be implemented and works well for both geometry and rasterization-bound models. We also propose a strategy to assign tiles to rendering nodes that effectively uses the available graphics resources, thus improving rendering performance.
this paper proposes a new Tensorial Representation of HSI color images, where each pixel is a 2 X 2 second order tensor, that can be represented by an ellipse. A proposed tensorial morphological gradient (TMG) is defi...
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ISBN:
(纸本)9780769529967
this paper proposes a new Tensorial Representation of HSI color images, where each pixel is a 2 X 2 second order tensor, that can be represented by an ellipse. A proposed tensorial morphological gradient (TMG) is defined as the maximum dissimilarity over the neighborhood determined by a structuring element, and is used in the watershed segmentation framework. Many tensor dissimilarity functions are tested and other color gradients are compared. the comparison uses a new methodology for qualitative evaluation of color image segmentation by watershed, where the watershed lines of the n most significant regions are overlaid on the original image for visual comparison. Experiments show that the TMG using Frobenius norm dissimilarity function presents superior segmentation results, in comparison to other tested gradients.
this paper aims at proposing an elastically deformable surface with use of differential geometric structures. On the basis of the theory of a Cosserat Surface, a computationally processable equation that relates the a...
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ISBN:
(纸本)0769522270
this paper aims at proposing an elastically deformable surface with use of differential geometric structures. On the basis of the theory of a Cosserat Surface, a computationally processable equation that relates the accumulated elastic energy and the variations in the differential geometry variables (metric and curvature tensors) of the deformable surface is presented On the basis of our analysis, we propose a novel algorithm to compute more precisely, without compromising the interface's simplicity, the potential deformation energy in terms of the derivatives of the surface. With our proposal, we may maintain the finite difference scheme for computing deformations iteratively. Some simulation results are included.
Scale dependent signal representations have proved to be useful in several imageprocessing applications. In this paper we define a toggle operator for binarization/segmentation purposes based on scaled versions of an...
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ISBN:
(纸本)0769526861
Scale dependent signal representations have proved to be useful in several imageprocessing applications. In this paper we define a toggle operator for binarization/segmentation purposes based on scaled versions of an image transformed by morphological operations. the toggle decision rule, determining the new value of a pixel, considers local spatial information, in contrast to other multiscale approaches that takes into account mainly global information (e.g., the scale signal under study). We show that the proposed operator can identify significant image extrema information in such a way that when it is used in a binarization process yields very good segmentation and filtering results. Our algorithm is validated against known threshold-based segmentation methods using images of different classes and subjected to different lighting conditions.
In this paper we present a novel method for estimating the effective number of independent variables in imaging applications that require multiple hypothesis testing. the method increases the statistical power of the ...
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ISBN:
(纸本)0769526861
In this paper we present a novel method for estimating the effective number of independent variables in imaging applications that require multiple hypothesis testing. the method increases the statistical power of the results by refuting the assumption of independence among variables, while keeping the probability of false positives low. It is based on the spectral graph theory, in which the variables are seen as the vertices of a complete undirected graph and the correlation matrix as the adjacency matrix that weights its edges. By computing the eigenvalues of the correlation matrix, it is possible to obtain valuable information about the dependence levels among the variables of the problem. the method is compared to other available models and its effectiveness illustrated in a case study on the morphology of the human corpus callosum.
Many applications of geometry processing and computer vision relies on geometric properties of curves, particularly their curvature. Several methods have been proposed to estimate the curvature of a planar curve, most...
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ISBN:
(纸本)0769522270
Many applications of geometry processing and computer vision relies on geometric properties of curves, particularly their curvature. Several methods have been proposed to estimate the curvature of a planar curve, most of them for curves in digital spaces. this work proposes a new method for curvature estimation based on weighted least square fitting and local arc-length approximation. Convergence analysis of this method and noise impact on the estimator accuracy are given. Numerical robustness issues are addressed with practical solutions. the implementation of the method is compared to other curvature estimation methods.
this work proposes an image sequence segmentation tool for video masking. It consist of a semi-automatic delineation tool of the object of interest, its segmentation, through the video sequence. the tool is based on w...
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ISBN:
(纸本)0769513301
this work proposes an image sequence segmentation tool for video masking. It consist of a semi-automatic delineation tool of the object of interest, its segmentation, through the video sequence. the tool is based on watershed by markers technique, where the markers are propagated from frame to frame using normalized correlation pattern matching algorithm.
To reconstruct a topologically consistent 3D surface model is a challenging problem. In this paper we present an algorithm that estimates from a range image, without registering and converting it into a volumetric dat...
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ISBN:
(纸本)0769513301
To reconstruct a topologically consistent 3D surface model is a challenging problem. In this paper we present an algorithm that estimates from a range image, without registering and converting it into a volumetric data, the most probable topology of a surface to be reconstructed. In our algorithm we start with a closed initial mesh and preserve its "closeness" during the reconstruction process. Some experiments were carried out to validate our proposal.
In this work, we introduce a new scheme to extract hierarchical isocontours from regular and irregular 2D sampled data and to encode it at single rate or progressively. A dynamic tessellation is used to represent and ...
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ISBN:
(纸本)0769522270
In this work, we introduce a new scheme to extract hierarchical isocontours from regular and irregular 2D sampled data and to encode it at single rate or progressively. A dynamic tessellation is used to represent and adapt the 2D data to the isocontour this adaptation induces a controlled multi-resolution representation of the isocontour We can then encode this representation and control the geometry and topology of the decoded isocontour the resulting algorithms form an efficient and flexible isocontour extraction and compression scheme.
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