CEIG14

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https://diglib.eg.org/handle/10.2312/7709

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Browsing CEIG14 by Subject "I.3.3 [Computer Graphics]"

Now showing 1 - 4 of 4
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    Depth from a Single Image Through User Interaction
    (The Eurographics Association, 2014) Lopez, Angeles; Garces, Elena; Gutierrez, Diego; Adolfo Munoz and Pere-Pau Vazquez
    In this paper we present a method to obtain a depth map from a single image of a scene by exploiting both image content and user interaction. Assuming that regions with low gradients will have similar depth values, we formulate the problem as an optimization process across a graph, where pixels are considered as nodes and edges between neighbouring pixels are assigned weights based on the image gradient. Starting from a number of userdefined constraints, depth values are propagated between highly connected nodes i.e. with small gradients. Such constraints include, for example, depth equalities and inequalities between pairs of pixels, and may include some information about perspective. This framework provides a depth map of the scene, which is useful for a number of applications.
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    GPU Visualization and Voxelization of Yarn-Level Cloth
    (The Eurographics Association, 2014) Lopez-Moreno, Jorge; Cirio, Gabriel; Miraut, David; Otaduy, Miguel Angel; Adolfo Munoz and Pere-Pau Vazquez
    Most popular methods in cloth rendering rely on volumetric data in order to model complex optical phenomena such as sub-surface scattering. Previous work represents yarns as a sequence of identical but rotated crosssections. While these approaches are able to produce very realistic illumination models, the required volumetric representation is difficult to compute and render, forfeiting any interactive feedback. In this paper, we introduce a method based on the GPU for simultaneous visualization and voxelization, suitable for both interactive and offline rendering. Our method can interactively voxelize millions of polygons into a 3D texture, generating a volume with sub-voxel accuracy which is suitable even for high-density weaving such as linen.
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    Image-Based Flow Transfer
    (The Eurographics Association, 2014) Bosch, Carles; Patow, Gustavo A.; Adolfo Munoz and Pere-Pau Vazquez
    Weathering phenomena are ubiquitous to urban environments. In particular, fluid flow becomes a specially representative but difficult phenomenon to reproduce. In order to produce realistic flow effects, it is possible to take advantage of the widespread availability of flow images on the internet, which can be used to gather key information about the flow. In this paper we present a technique that allows transferring flow phenomena between photographs, adapting the flow to the target image and giving the user flexibility and control through specifically tailored parameters. This is done through two types of control curves: a fitted theoretical curve for the mass of deposited material, and a control curve extracted from the images for the color. This way, the user has a set of simple and intuitive parameters and tools to control the flow phenomena on the target image. To illustrate our technique, we present a complete set of images that somewhat cover a large range of flow phenomena in urban environments.
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    A System Proposal for Interactive Deformation of Large Medical Volumes
    (The Eurographics Association, 2014) Aguilera, Alejandro Rodríguez; Leon, Alejandro; Escudero, Luis López; Sánchez, Manuel García; Adolfo Munoz and Pere-Pau Vazquez
    In the field of volume deformation, an open research topic is the interactive and physically plausible deformation and rendering of large medical volumes. Many approaches to deform volumetric models have been proposed, offering a trade-off between realism and model resolution depending on the goal. In this paper, we study the main techniques to deform volumetric models, focusing on the works that address interactive realistic deformation of large models and we outline the requirements needed to build an integrated system to interactively deform and visualize large volumes using the GPU. We also present a prototype of application that shows the viability of implementing such a system. For this prototype, we propose an enhanced deformation technique and a new fast deformed volume visualization scheme, assuring the system interactivity at any time.