Construction of 3D Triangles on Dupin Cyclides
TL;DR: The properties of these surfaces are used to prove that three families of circles meridian arcs, parallel arcs, and Villarceau circles can be computed on every Dupin cyclide, and a geometric algorithm to compute these circles so that they define the edges of a 3D triangle on the Dupincyclide is presented.
Abstract: This paper considers the conversion of the parametric Bezier surfaces, classically used in CAD-CAM, into patched of a class of non-spherical degree 4 algebraic surfaces called Dupin cyclides, and the definition of 3D triangle with circular edges on Dupin cyclides. Dupin cyclides was discovered by the French mathematician Pierre-Charles Dupin at the beginning of the 19th century. A Dupin cyclide has one parametric equation, two implicit equations, and a set of circular lines of curvature. The authors use the properties of these surfaces to prove that three families of circles meridian arcs, parallel arcs, and Villarceau circles can be computed on every Dupin cyclide. A geometric algorithm to compute these circles so that they define the edges of a 3D triangle on the Dupin cyclide is presented. Examples of conversions and 3D triangles are also presented to illustrate the proposed algorithms.
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01 Jan 2013
TL;DR: The authors describe how to create and evaluate a visual attention system tailored for interacting with a computer vision system so that it adapts its processing according to the interest (or salience) of each element of the scene.
Abstract: In the field of scene analysis for computer vision, a trade-off must be found between the quality of the results expected and the amount of computer resources allocated for each task. Using an adaptive vision system provides a more flexible solution as its analysis strategy can be changed according to the information available concerning the execution context. The authors describe how to create and evaluate a visual attention system tailored for interacting with a computer vision system so that it adapts its processing according to the interest (or salience) of each element of the scene. The authors propose a new set of constraints called ‘PAIRED’ to evaluate the adequacy of a model with respect to its different applications. The authors then justify why dynamical systems are a good choice for visual attention simulation, and we show that predator-prey models provide good properties for simulating the dynamic competition between different kinds of information. They present different results (cross-correlation, Kullback-Leibler divergence, normalized scanpath salience) that demonstrate that, in spite of being fast and highly configurable, their results are as plausible as existing models designed for high biological fidelity.
15 citations
Book•
30 Apr 2013
TL;DR: Intelligent Computer Vision and Image Processing: Innovation, Application, and Design provides methods and research on various disciplines related to the science and technology of machines.
Abstract: Innovations in computer vision technology continue to advance the applications and design of image processing and its influence on multimedia applications.Intelligent Computer Vision and Image Processing: Innovation, Application, and Design provides methods and research on various disciplines related to the science and technology of machines. This reference source is essential for academicians, researchers, and practitioners interested in the latest developments and innovations in computer science, education, and security.
15 citations
TL;DR: This paper presents a novel approach for region of interest (ROI) extraction in infrared images based on the one-bit transform that can be used as an effective pre-process for target detection and tracking algorithms inrared images.
Abstract: This paper presents a novel approach for region of interest (ROI) extraction in infrared images based on the one-bit transform. Potential interest regions in the infrared image are obtained by a target mask that is obtained using the one-bit transform in a local way. The histograms of the original image and the masked image are compared and the histogram region that remains unchanged is used to obtain an automated threshold value that is then utilized to detect the ROI in the infrared image. The proposed approach can be used as an effective pre-process for target detection and tracking algorithms in infrared images.
11 citations
TL;DR: A new stepwise approaching and recurring threshold search algorithm based on two-dimensional maximum entropy principle was proposed by studying recurring formulation optimized of two- dimensional maximum entropy in order to realize to detect target and extract ROI of serial images under complex background.
Abstract: Infrared imaging guidance is a research hotspot in accurate terminal guidance field now. An idea on automatic extraction of region (ROI) of interest in infrared serial images is proposed in order to treat intelligently infrared serial images which are captured. The target detection algorithm of target is researched and the applying scene of the target detection algorithm is confirmed based on analysis for the features of infrared serial images. According to differences of detection algorithm for infrared serial images between static and dynamic scenes, the corresponding detection and extraction algorithm of ROI is discussed respectively. The algorithms are all simulated in real scene. A new stepwise approaching and recurring threshold search algorithm based on two-dimensional maximum entropy principle was proposed by studying recurring formulation optimized of two-dimensional maximum entropy in order to realize to detect target and extract ROI of serial images under complex background. The algorithm above realizes automatic extraction of ROI in Infrared serial images. The results improve the efficiency of accurate terminal guidance and they have good application value by practicing.
6 citations
01 Jan 2012
TL;DR: In this chapter, after introducing methods of image processing related to feature extraction, applicable methods for visual positioning are discussed with state-of-the-art examples.
Abstract: Numerous techniques for obtaining motion and location related information are needed for obtaining seamless positioning capability with smartphones. High-quality cameras are nowadays widely available in portable devices and can provide necessary redundant data about the user’s surroundings in addition to the other sensors usable for positioning purposes. In this chapter, after introducing methods of image processing related to feature extraction, applicable methods for visual positioning are discussed with state-of-the-art examples. Regardless whether the visual-based positioning is based on reference images in a database or using information obtained from consecutive images, the first steps of pre-processing are similar to obtain noiseless images for accurate calculations and to retrieve the required camera parameters. Smartphones have limited computational resources and that restricts the methods available for image processing. To carry out the visual positioning function, features in images are either matched to corresponding features in consecutive images, or to a database. Obtaining the location can be performed with matching the query image to a database of reference images equipped with location information. Alternatively, the attitude and position change can be resolved from consecutive images to provide localization augmentation that may be fused with other sensor information. When smartphones are concerned, the restricted resources however bring about challenges that are the focus in this chapter. DOI: 10.4018/978-1-4666-1827-5.ch006
4 citations
References
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Book•
01 Feb 1999
TL;DR: The second edition of NURBS (Non-Uniform Rational B-Splines) incorporates new research results and a chapter on Pythagorean curves, a development that shows promise in applications such as NC machining or robot motion control.
Abstract: From the Publisher:
NURBS (Non-Uniform Rational B-Splines) have become the de facto standard for geometric definitions in CAD/CAM and computer graphics. This well-known book covers NURBS from their geometric beginnings to their industrial applications. The second edition incorporates new research results and a chapter on Pythagorean curves, a development that shows promise in applications such as NC machining or robot motion control. More than fifty new figures have been added.
189 citations
"Construction of 3D Triangles on Dup..." refers methods in this paper
...For a standard rational quadratic Bézier curve, w 0 and w 2 are equal to 1, while w 1 can be used to control the type of the conic defined by the curve (Farin, 1993, 1999; Garnier, 2007)....
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TL;DR: Extensions are made to the methods of Pratt (1990) for the use of cyclides in solid modelling, with particular regard to their application as blend surfaces and new insights are given into the geometry and Bezier representation of cyclide surface patches.
137 citations
01 Apr 2007
100 citations
Book•
01 Jan 2007
TL;DR: Design Pattern Formalization Techniques focuses on formalizing the solution element of patterns, providing tangible benefits to pattern users, researchers, scholars, academicians, practitioners and students working in the field of design patterns and software reuse.
Abstract: Many formal approaches for pattern specification are emerging as a means to cope with the inherent shortcomings of informal description. Design Pattern Formalization Techniques presents multiple mathematical, formal approaches for pattern specification, emphasizing on software development processes for engineering disciplines. Design Pattern Formalization Techniques focuses on formalizing the solution element of patterns, providing tangible benefits to pattern users, researchers, scholars, academicians, practitioners and students working in the field of design patterns and software reuse. Design Pattern Formalization Techniques explains details on several specification languages, allowing readers to choose the most suitable formal technique to solve their specific inquiries.
88 citations
TL;DR: It is shown that Dupin cyclides, as surfaces in computer-aided geometric design (CAGD), have attractive properties such as low algebraic degree, rational parametric forms, and an easily comprehensible geometric representation using simple and intuitive geometric parameters.
Abstract: It is shown that Dupin cyclides (C.P. Dupin, 1822), as surfaces in computer-aided geometric design (CAGD), have attractive properties such as low algebraic degree, rational parametric forms, and an easily comprehensible geometric representation using simple and intuitive geometric parameters. Their alternative representations permit the transition between forms when one or the other is more convenient for a specific purpose. Cyclides provide is useful extension of geometric coverage in solid modeling, primarily as blending surfaces for many commonly occurring situations. The geometry, properties, and uses of the Dupin cyclide in free-form surface modeling and blending are discussed. >
65 citations