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Item Liquid Penetration Modeling for Cloth Dyeing(The Eurographics Association, 2007) Morimoto, Yuki; Tsuruno, Reiji; Tomimatsu, Kiyoshi; Douglas W. Cunningham and Gary Meyer and Laszlo NeumannThis paper presents a model of cloth dyeing using the characteristics of the thread and weave pattern. The proposed dyeing model is based on Fick s second law that defines the molecular transfer under translational diffusion [Fic85]. The algorithm in the proposed model calculates the dyeing distribution from parameters such as the amount of dyeing, saturated amount, and pressure in each cell on a timeline. We improve the algorithm based on Fick s second law to consider a woven cloth structure and describe the proposed model of the structure of woven cloth as a two-layer cellular model. We then visualize the cloth using a simple 2D shading method of asperity by using the color distribution on a dyed image of real woven cloth. In addition, we provide a method for producing dyeing patterns without dyeing diffusion. The proposed method produces images that capture several of the characteristics of dyeing observed in real dyed cloth.Item Design of Multi-dimensional Transfer Functions Using Dimensional Reduction(The Eurographics Association, 2007) Pinto, Francisco de Moura; Freitas, Carla M. D. S.; K. Museth and T. Moeller and A. YnnermanDirect volume rendering techniques allow visualization of volume data without extracting intermediate geometry. The mapping from voxel attributes to optical properties is performed by transfer functions which, consequently, play a crucial role in building informative images from the data. One-dimensional transfer functions, which are based only on a scalar value per voxel, often do not provide proper visualizations. On the other hand, multidimensional transfer functions can perform more sophisticated data classification, based on vectorial voxel signatures. The transfer function design is a non-trivial and unintuitive task, especially in the multi-dimensional case. In this paper we propose a multi-dimensional transfer function design technique that uses self-organizing maps to perform dimensional reduction. Our approach gives uniform treatment to volume data containing voxel signatures of arbitrary dimension, and allows the use of any type of voxel attribute as part of the voxel signatures.Item Applications of High Precision Imaging Polarimetry(The Eurographics Association, 2008) Neumann, Laszlo; Hegedus, Ramon; Horváth, Gábor; Garcia, Rafael; Douglas W. Cunningham and Victoria Interrante and Paul Brown and Jon McCormackWe propose the use of imaging polarimetry for general photography, which is a relatively young technique allowing the determination of polarized components of the light coming from extended objects or scenes. In this paper high resolution and accurate methods are introduced to determine the two linearly polarized components (Q;U) of light. The CIE Luv color space is used in this work to visualize the triplet of (I;Q;U) polarization image components. The structure of this color space is also highly appropriate to represent other attributes of linearly polarized light, such as the polarized intensity, degree and the angle of polarization. The accurately measured polarization components can also be efficiently used for image enhancement. In this direction, a new, polarization-based de-reflection method is proposed. This method is an optimal pixel-wise extension of the widely used photographical polarization filtering. Our method is also capable of amplifying the specular effects. Another application is de-hazing, which removes the linearly polarized component of the haze present in natural scenes, and results in a sharp and color-corrected image. Furthermore, the different combinations of visible and infrared polarization channels enable great possibilities in further de-hazing and to create artistic images.Item Meshless Statistical Occlusion Computation(The Eurographics Association, 2012) Fouquet, François; Farrugia, Jean-Philippe; Iehl, Jean-Claude; Dupuy, Jonathan; Andrea Fusiello and Michael WimmerThis paper presents a new method to evaluate visibility from a point cloud by using a meshless statistical representation. The resulting evaluation uses much less memory than previous work while still producing high quality images, making it suitable for memory limited systems. The obtained results are exposed through the evaluation of shadow maps using a point cloud created from range images and are compared to current methods, which rely on mesh reconstruction techniques.Item General Linear Cameras with Finite Aperture(The Eurographics Association, 2007) Adams, Andrew; Levoy, Marc; Jan Kautz and Sumanta PattanaikA pinhole camera selects a two-dimensional set of rays from the four-dimensional light field. Pinhole cameras are a type of general linear camera, defined as planar 2D slices of the 4D light field. Cameras with finite apertures can be considered as the summation of a collection of pinhole cameras. In the limit they evaluate a two-dimensional integral of the four-dimensional light field. Hence a general linear camera with finite aperture factors the 4D light field into two integrated dimensions and two imaged dimensions. We present a simple framework for representing these slices and integral projections, based on certain eigenspaces in a two-plane parameterization of the light field. Our framework allows for easy analysis of focus and perspective, and it demonstrates their dual nature. Using our framework, we present analogous taxonomies of perspective and focus, placing within them the familiar perspective, orthographic, cross-slit, and bilinear cameras; astigmatic and anastigmatic focus; and several other varieties of perspective and focus.Item Goblins by Spheroidal Weathering(The Eurographics Association, 2007) Beardall, Mathew; Farley, Mckay; Ouderkirk, Darius; Smith, Jeremy; Jones, Michael; Egbert, Parris; D. Ebert and S. MerillouHeight map models of terrain are computationally efficient but can not represent terrain with concave surfaces. We present an algorithm for generating sandstone goblins using a simulation of spheroidal weathering. Sandstone goblins are a kind of hoodoo which are characterized by rounded concave shapes. The weathering simulation uses bubbles centered on axis aligned voxels to approximate geometry-dependent effects of spheroidal weathering. We demonstrate that the algorithm, together with appropriate surface textures, produces visually plausible goblins at near interactive speeds for most simulation parameters.Item Methodologies for Connected Structured Idealized Ice Crystal Growth Models(The Eurographics Association, 2011) El-Alem, Yousef; Roberts, Jonathan C.; R. Laramee and I. S. LimIce crystals are beautiful and intricate shapes. Our goal is to create ice crystal and other models with similar structure and render them in three-dimensions. Many of the current algorithms apply complex physics-based simulation algorithms to simulate the crystal growth, most are two-dimensional forms, and importantly they are made up of many disconnected parts (pixels); consequently they cannot be easily stored as a single model. However, our approach is to generate visually appealing 3d structures, rather than accurately model reality, that are geometrically connected together to form one connected model. These idealized structures can be easily stored, manipulated and included with other 3d-models and into virtual environments. This work is part of a larger project, thus in this poster presentation we merely describe several alternative methodologies to achieve this effect.Item Pushing Time-of-Flight Scanners to the Limit(The Eurographics Association, 2009) Callieri, Marco; Cignoni, Paolo; Dellepiane, Matteo; Scopigno, Roberto; Kurt Debattista and Cinzia Perlingieri and Denis Pitzalis and Sandro SpinaThe paper describes a pipeline for 3D scanning acquisition and processing that allow to exploit the utmost precision and quality out of ToF scanners. The proposed approach capitalize on the knowledge of the distribution of the noise to apply sophisticated fairing techniques for cleaning up the data. Leveraging on the very dense sampling of this kind of scanners we show that is possible to attain high accuracy. We present a practical application of the proposed approach for the scanning of a large (5mt) statue with millimetric precision.Item Sonar Explorer: A New Tool for Visualization of Fish Schools from 3D Sonar Data(The Eurographics Association, 2007) Balabanian, Jean-Paul; Viola, Ivan; Ona, Egil; Patel, Ruben; Groeller, Eduard; K. Museth and T. Moeller and A. YnnermanWe present a novel framework for analysis and visualization of fish schools in 3D sonar surveys. The 3D sonar technology is new and there have not been applications to visualize the data in 3D. We have created an application called Sonar Explorer that satisfies the requirements of domain scientists. Sonar Explorer provides easy and intuitive semi-automatic fish school tracking and survey map generation. The overall pipeline is described and all pipeline stages relevant for visualization are highlighted. We present techniques to deal with 3D sonar data specifics: highly anisotropic volume data aligned on a curvilinear grid. Domain scientists provide initial impressions on interaction and outlook.Item A Fast Algorithm for Painterly Rendering on Mobile Devices(The Eurographics Association, 2008) Mukundan, R.; Han, C.; Ik Soo Lim and Wen TangWith the rapid growth of mobile graphics applications, non-photorealistic rendering algorithms developed particularly for devices with limited processor capabilities have become important in the areas of games design and augmented reality. This paper presents a fast painterly rendering algorithm suitable for implementation on mobile phones. Connected components in an image are identified and stored in an index buffer, using a sequential scan. Most of the subsequent processing is done only on this index buffer that contains one integer value per pixel. The proposed method does not use recursive procedures, complex floating-point computations, or texture processing functions. The painterly rendered effect is produced by suitably modifying the boundary of connected components and highlighting edges using entries from the index buffer. The paper presents the theoretical framework for the algorithm, implementation aspects and results.