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Notes on a linguistic description as the basis for automatic image understanding

Ryszard Tadeusiewicz, Marek R. Ogiela, Piotr S. Szczepaniak (2009)

International Journal of Applied Mathematics and Computer Science

The main paradigm of image understanding and a concept for its practical machine realisation are presented. The crucial elements of the presented approach are the formalisation of human knowledge about the class of images that are to be automatically interpreted, a linguistic description and the realization of cognitive resonance.

Numerical algorithms for perspective shape from shading

Michael Breuss, Emiliano Cristiani, Jean-Denis Durou, Maurizio Falcone, Oliver Vogel (2010)

Kybernetika

The Shape-From-Shading (SFS) problem is a fundamental and classic problem in computer vision. It amounts to compute the 3-D depth of objects in a single given 2-D image. This is done by exploiting information about the illumination and the image brightness. We deal with a recent model for Perspective SFS (PSFS) for Lambertian surfaces. It is defined by a Hamilton–Jacobi equation and complemented by state constraints boundary conditions. In this paper we investigate and compare three state-of-the-art...

Optimization of the maximum likelihood estimator for determining the intrinsic dimensionality of high-dimensional data

Rasa Karbauskaitė, Gintautas Dzemyda (2015)

International Journal of Applied Mathematics and Computer Science

One of the problems in the analysis of the set of images of a moving object is to evaluate the degree of freedom of motion and the angle of rotation. Here the intrinsic dimensionality of multidimensional data, characterizing the set of images, can be used. Usually, the image may be represented by a high-dimensional point whose dimensionality depends on the number of pixels in the image. The knowledge of the intrinsic dimensionality of a data set is very useful information in exploratory data analysis,...

Parametric logarithmic type image processing for contrast based auto-focus in extreme lighting conditions

Corneliu Florea, Laura Florea (2013)

International Journal of Applied Mathematics and Computer Science

While most of state-of-the-art image processing techniques were built under the so-called classical linear image processing, an alternative that presents superior behavior for specific applications comes in the form of Logarithmic Type Image Processing (LTIP). This refers to mathematical models constructed for the representation and processing of gray tones images. In this paper we describe a general mathematical framework that allows extensions of these models by various means while preserving...

PDF Enhancements Tools for a Digital Library

Hatlapatka, Radim, Sojka, Petr (2010)

Towards a Digital Mathematics Library. Paris, France, July 7-8th, 2010

This paper describes several innovative PDF document enhancements and tools that can be used when building a digital library. The main result presented in this paper is the PDF re-compression tool, developed using the jbig2enc encoder called pdfJbIm. This re-compression tool enables the size of the original bitonal PDFs to be, on average, downsized by one third. Some modifications to the jbig2enc encoder that increase the compression ratio even further are also described here. Together with another...

Processing of Byzantine Neume Notation in Ancient Historical Manuscripts

Laskov, Lasko (2011)

Serdica Journal of Computing

This article presents the principal results of the doctoral thesis “Recognition of neume notation in historical documents” by Lasko Laskov (Institute of Mathematics and Informatics at Bulgarian Academy of Sciences), successfully defended before the Specialized Academic Council for Informatics and Mathematical Modelling on 07 June 2010.Byzantine neume notation is a specific form of note script, used by the Orthodox Christian Church since ancient times until nowadays for writing music and musical...

Producing MathML with Tralics

Grimm, José (2010)

Towards a Digital Mathematics Library. Paris, France, July 7-8th, 2010

We describe here how Tralics can be used to convert LaTeX documents into XML or HTML. It uses an ad-hoc DTD (a simplification of the TEI), but the translation of the math formulas is conforming to the presentation MathML 2.0 recommendations. We explain how to run and parametrize the software. We give an overview of the various MathML constructs, and how they are rendered by different browsers.

Quad-tree Based Finite Volume Method for Diffusion Equations with Application to SAR Imaged Filtering

Zuzana KRIVÁ, Juraj PAPČO, Jakub VANKO (2015)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

In this paper we present a method to remove the noise by applying the Perona Malik algorithm working on an irregular computational grid. This grid is obtained with a quad-tree technique and is adapted to the image intensities—pixels with similar intensities can form large elements. We apply this algorithm to remove the speckle noise present in SAR images, i.e., images obtained by radars with a synthetic aperture enabling to increase their resolution in an electronic way. The presence of the speckle...

Quasiconvex relaxation of multidimensional control problems with integrands f(t, ξ, v)

Marcus Wagner (2011)

ESAIM: Control, Optimisation and Calculus of Variations

We prove a general relaxation theorem for multidimensional control problems of Dieudonné-Rashevsky type with nonconvex integrands f(t, ξ, v) in presence of a convex control restriction. The relaxed problem, wherein the integrand f has been replaced by its lower semicontinuous quasiconvex envelope with respect to the gradient variable, possesses the same finite minimal value as the original problem, and admits a global minimizer. As an application, we provide existence theorems for the image registration...

Quasiconvex relaxation of multidimensional control problems with integrands f(t, ξ, v)

Marcus Wagner (2011)

ESAIM: Control, Optimisation and Calculus of Variations

We prove a general relaxation theorem for multidimensional control problems of Dieudonné-Rashevsky type with nonconvex integrands f(t, ξ, v) in presence of a convex control restriction. The relaxed problem, wherein the integrand f has been replaced by its lower semicontinuous quasiconvex envelope with respect to the gradient variable, possesses the same finite minimal value as the original problem, and admits a global minimizer. As an application, we provide existence theorems for the image registration...

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