Proceedings of the 31st Spring Conference on Computer Graphics最新文献

{"title":"Fuzzy feature tracking: visual analysis of industrial 4D-XCT data","authors":"Andreas Reh, Aleksandr Amirkhanov, J. Kastner, E. Gröller, C. Heinzl","doi":"10.1145/2788539.2788558","DOIUrl":"https://doi.org/10.1145/2788539.2788558","url":null,"abstract":"In-situ analysis is becoming increasingly important in the evaluation of existing as well as novel materials and components. In this domain, specialists require answers on questions such as: How does a process change internal and external structures of a component? or How do the internal features evolve? In this work, we present a novel integrated visual analysis tool to evaluate series of X-ray Computed Tomography (XCT) data. We therefore process volume datasets of a series of XCT scans, which non destructively cover the evolution of a process by in-situ scans. After the extraction of individual features, a feature tracking algorithm is applied to detect changes of features throughout the series as events. We distinguish between creation, continuation, split, merge and dissipation events. As an explicit tracking is not always possible, we introduce the computation of a Tracking Uncertainty. We visualize the data together with the determined events in multiple linked-views, each emphasizing individual aspects of the 4D-XCT dataset series: A Volume Player and a 3D Data View show the spatial feature information, whereas the global overview of the feature evolution is visualized in the Event Explorer. The Event Explorer allows for interactive exploration and selection of the events of interest. The selection is further used as basis to calculate a Fuzzy Tracking Graph visualizing the global evolution of the features over the whole series. We finally demonstrate the results and advantages of the proposed tool using various real world applications, such as a wood shrinkage analysis and an AlSiC alloy under thermal load.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124193273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automated facial landmark detection, comparison and visualization","authors":"Marek Galvánek, K. Furmanová, I. Chalas, Jirí Sochor","doi":"10.1145/2788539.2788540","DOIUrl":"https://doi.org/10.1145/2788539.2788540","url":null,"abstract":"Anthropometric facial landmarks and their detection has wide application in anthropology and forensic science. More specifically, these landmarks play an important role in facial comparison, in the analysis of morphological changes during human growth and in searching for the variability of human faces (e.g., sexual dimorphism). The automatic extraction of landmarks is a challenging area and specific visualization methods serving for the comparison are crucial for the correct interpretation of the results. In this paper we introduce a novel system which incorporates a newly proposed algorithm for automatic landmark detection. The algorithm is based on surface curvature and symmetric profile extraction. The landmarks are then used in the Generalized Procrustes analysis for facial comparison. Our system also introduces appropriate visualization methods supporting the presentation and understandability of the results.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128095710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hairstyles modeling for police identikits","authors":"Martínek Petr, Kolingerová Ivana","doi":"10.1145/2788539.2788561","DOIUrl":"https://doi.org/10.1145/2788539.2788561","url":null,"abstract":"Hairstyle is an important part of a human head as the hair can completely change the appearance of a person. Therefore hairstyle is important in the creation of identikits - human models for identification practices, namely for the police use. In this paper we propose a new method of hair modeling which allows modeling of common hairstyles in a reasonable time as needed by the police.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"51 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128845088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two dimensional hidden surface removal with frame-to-frame coherence","authors":"John G. Whitington","doi":"10.1145/2788539.2788560","DOIUrl":"https://doi.org/10.1145/2788539.2788560","url":null,"abstract":"We describe a hidden surface removal algorithm for two-dimensional layered scenes built from arbitrary primitives, particularly suited to interaction and animation in rich scenes (for example, in illustration). The method makes use of a set-based raster representation to implement a front-to-back rendering model which analyses and dramatically reduces the amount of rasterization and composition required to render a scene. The method is extended to add frame-to-frame coherence analysis and caching for interactive or animated scenes. A powerful system of primitive-combiners called filters is described, which preserves the efficiencies of the algorithm in highly complicated scenes. The set representation is extended to solve the problem of correlated mattes, leading to an efficient solution for high quality antialiasing. A prototype implementation has been prepared.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115969691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shallow water simulation based on SPH with irregular simulation domains","authors":"M. Chládek, R. Durikovic","doi":"10.1145/2788539.2788547","DOIUrl":"https://doi.org/10.1145/2788539.2788547","url":null,"abstract":"We propose a shallow water simulation in a Lagrangian way. Smoothed particle hydrodynamic (SPH) is used to solve shallow water equation by which we avoid discretization of the whole simulation domain and get an easy handling of sparse and irregular simulation domains. In contrast to the Eulerian methods in the context of shallow water equations much less attention has been paid to the Lagrangian simulation methods. Therefore many problems remained unsolved and prevented a practical use of Lagrangian shallow water simulation in computer graphics. We concentrate on several issues connected to the simulation. First, we increase the accuracy of the smoothed particle hydrodynamics approximation by applying a correction to the kernel function used in the simulation. Second, we introduce a novel boundary handling algorithm which can handle arbitrary boundary domains. Even irregular and complicated boundaries pose no problem and introduce only small computational overhead. Third, with the increased accuracy we use the fluid height to generate a flat fluid surface. All the proposed methods can be easily integrated into the smoothed particle hydrodynamics framework. Computational fluid dynamics has been a popular research area in computer graphics for many years. The most work has been done in the field of 3-dimensional fluid simulation. One of the most widely used approaches is the use of shallow water equations (SWE), which are the simplified version of Navier-Stokes equations for an inviscid 2D fluid flow. The SWE are usually solved in Eulerian way using a grid, but they are not suitable for irregular domains which are not aligned with the grid. In this paper we propose the shallow water simulation in Lagrangian way to avoid discretization of the whole simulation domain and get an easier handling of complicated boundary domains. The novelty is that we utilize smoothed particle hydrodynamics (SPH) to solve the SWE. There is the list of problems to which the proposed solution provides answers: • The use of SPH results in inaccurate evaluation of quantities, especially in areas near boundaries because of particle deficiency. We increase the accuracy by applying a correction to the kernel functions used in the simulation. • The existing methods for boundary handling are difficult to set up correctly. Their use in the handling of irregular boundaries is also problematic because of computational complexity. We propose a novel boundary handling for SPH-based shallow water simulation handling boundary domains with arbitrary complexity. • Achieving flat fluid surface is problematic because of irregular fluid sampling. We propose a new method producing flat fluid surface using the fluid height.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132807302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physically inspired stretching for skinning animation of non-rigid bodies","authors":"Michal Piovarči, Martin Madaras, R. Durikovic","doi":"10.1145/2788539.2788545","DOIUrl":"https://doi.org/10.1145/2788539.2788545","url":null,"abstract":"We propose a physically inspired stretching model for non-rigid bodies with linear skeletons. Given an input model composed of linear skeleton segments, it extract scaling matrices that can be directly used in skinning animation. The stretching model evaluates stretching of the body cause by gravitational force and stretching of the body caused by muscle contraction. Our model is based on small deformation theory, which can be directly applied on cylindrical shapes. Since the input body may differ from a cylindrical shape, it is decomposed into several cylindrical parts and stretching factors are calculated for each part individually. Next, the body is stretched along the skeleton based on the function derived from the sum of skeleton curvature. Finally, a system for the visualization of a particle-based simulation using linear blend skinning is created and enhanced with out stretching model.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123939294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artifact-free color interpolation","authors":"Jens Ogniewski","doi":"10.1145/2788539.2788556","DOIUrl":"https://doi.org/10.1145/2788539.2788556","url":null,"abstract":"Color interpolation is still the most used method for image upsampling, since it offers the simplest and therefore fastest algorithms. However, in recent years research concentrated on other techniques to counter the shortcomings of interpolation techniques (like color artifacts or the fact that interpolation does not take statistics into account), while interpolation itself has ceased to be an active research topic. Still, current interpolation techniques can be improved. Especially it should be possible to avoid color artifacts by carefully choosing the correct interpolation schemes. In this paper we derive mathematical constraints which need to be fulfilled to reach an artifact-free interpolation, and use these to develop an interpolation method which is basically a self-configuring cubic spline.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"185 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115900091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A general framework for constrained mesh parameterization","authors":"Márton Vaitkus, T. Várady","doi":"10.1145/2788539.2788541","DOIUrl":"https://doi.org/10.1145/2788539.2788541","url":null,"abstract":"Parameterizing or flattening a triangle mesh is necessary for many applications in computer graphics and geometry. While mesh parameterization is a very popular research topic, the vast majority of the literature is focused on minimizing distortion or satisfying constraints related to certain applications such as texturing or quadrilateral remeshing. Certain downstream applications require adherence to more general, geometric constraints -- possibly at the cost of higher distortion. These geometric constraints include requirements such as certain vertices lie on some line or circle, or a planar curve or developable region keeps its shape during parameterization. We present a framework for enforcing such constraints, motivated by the As-Rigid-As-Possible parameterization method, and demonstrate its effectiveness through several examples.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121121101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface reflectance characterization by statistical tools","authors":"V. Havran, M. Sbert","doi":"10.1145/2788539.2788544","DOIUrl":"https://doi.org/10.1145/2788539.2788544","url":null,"abstract":"The classification of surface reflectance functions as diffuse, specular, and glossy has been introduced by Heckbert more than two decades ago. Many rendering algorithms are dependent on such a classification, as different kinds of light transport will be handled by specialized methods, for example, caustics require specular bounce or refraction. As the surface reflectance models are more and more rich and descriptive including those based on measured data, it has not been possible to keep such a characterization simple. Each surface reflectance model is mostly handled separately, or alternatively, the rendering algorithm restricts itself to the use of some subset of reflectance models. We provide a general characterization for arbitrary surface reflectance representation by means of statistical tools. We demonstrate by rendered images using Matusik's BRDF data sets for two environment maps and two 3D objects (sphere and Utah teapot) that there is even a visible perceptual correspondence to the proposed surface reflectance characterization, when we use monochromatic surface reflectance and the albedo is normalized for rendering images to equalize perceived brightness. The proposed characterization is intended to be used to optimize rendering algorithms.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131230821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On using the D2 descriptor in search for the best view","authors":"I. Varhanikova, Z. Černeková, E. Sikudová, D. Behal","doi":"10.1145/2788539.2788555","DOIUrl":"https://doi.org/10.1145/2788539.2788555","url":null,"abstract":"In this paper, we present a novel approach to searching for the best view of museum art pieces. There is big variety of objects situated in virtual museums and one method for determining the best view on all of them is not enough. In our work we categorize the objects into several groups to determine which method is suitable for which kind of objects. The D2 Shape Descriptor, which represents the distribution of Euclidean distances between pairs of randomly selected points on the surface of a 3D model is investigated on a database of object from 5 semantic categories. It turns out that D2 shape descriptor is not capable to discriminate these categories correctly and different descriptors must be investigated.","PeriodicalId":131696,"journal":{"name":"Proceedings of the 31st Spring Conference on Computer Graphics","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121969084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}