in the current iris recognition systems, noise removing step is only used to detect noisy parts of the iris region and features extracted from there will be excluded in matching step. whereas depending on the filter structure used in feature extraction, the noisy parts may influence relevant features. to the best of our knowledge, the effect of noise factors on feature extraction has not been c...

In this paper we deal with the problem of reconstructing surfaces from unorganized sets of points, while capturing the significant geometry details of the modelled surface, such as edges, flat regions and corners. This is obtained by exploiting the good approximation capabilities of the Radial Basis Functions (RBF), the local nature of the method proposed in [1], and introducing information on ...

This paper presents a segmentation scheme for images containing both smooth regions and textures. It is based on a vector-valued anisotropic diffusion on a combined color/Gabor feature space, followed by a hierarchical segmentation using dynamics of multiscale ’generalized gradient’ watersheds. The proposed method gives good segmentation results and is shown to be more effective than its counte...

Feature curves on surface meshes are usually defined solely based on local shape properties such as dihedral angles and principal curvatures. From the application perspective, however, the meaningfulness of a network of feature curves also depends on a global scale parameter that takes the distance between feature curves into account, i.e., on a coarse scale, nearby feature curves should be mer...

The diffraction beam from an anisotropic, random, rough surface is investigated. Two kinds of anisotropic surfaces with either a correlation-length anisotropy or a scaling anisotropy are considered. For the correlationlength anisotropic surface with an isotropic scaling, the shape of the diffraction beam directly reflects the surface anisotropy under any diffraction condition. However, for the ...

This paper describes an effective anisotropic mesh adaptation procedure for general 3D geometries using mesh modification operations. The procedure consists of four interacted high level components: refinement, coarsening, projecting boundary vertices and shape correction. All components are governed by an anisotropic mesh metric field that represents the desired element size and shape distribu...

We cast the problem of inferring the 3D shape of a scene from a collection of defocused images in the framework of anisotropic diffusion. We propose a novel algorithm that can estimate the shape of a scene by inferring the diffusion coefficient of a heat equation. The method is optimal, as we pose it as the minimization of a certain cost functional based on the input images, and fast. Furthermo...

An essential step in feature extraction is the calculation of attribute sets describing the characteristics of a feature. Often, attribute sets include the position, size, and orientation of the feature. These attributes are very important, but they do not provide a good approximation of the shape of a feature. For better shape description, a more sophisticated method is needed. This paper desc...