Computers and Graphics: X最新文献

A kernel for multi-parameter persistent homology 一个多参数持久同源的内核

Computers and Graphics: X Pub Date : 2019-12-01 DOI: 10.1016/j.cagx.2019.100005

René Corbet , Ulderico Fugacci , Michael Kerber , Claudia Landi , Bei Wang

引用次数: 37

Real-time neural network prediction for handling two-hands mutual occlusions 双手互咬合处理的实时神经网络预测

Computers and Graphics: X Pub Date : 2019-12-01 DOI: 10.1016/j.cagx.2019.100011

Dario Pavllo, Mathias Delahaye, Thibault Porssut, Bruno Herbelin, Ronan Boulic

{"title":"Real-time neural network prediction for handling two-hands mutual occlusions","authors":"Dario Pavllo, Mathias Delahaye, Thibault Porssut, Bruno Herbelin, Ronan Boulic","doi":"10.1016/j.cagx.2019.100011","DOIUrl":"10.1016/j.cagx.2019.100011","url":null,"abstract":"<div><p>Hands deserve particular attention in virtual reality (VR) applications because they represent our primary means for interacting with the environment. Although marker-based motion capture works adequately for full body tracking, it is less reliable for small body parts such as hands and fingers which are often occluded when captured optically, thus leading VR professionals to rely on additional systems (e.g. inertial trackers). We present a machine learning pipeline to track hands and fingers using solely a motion capture system based on cameras and active markers. Our finger animation is performed by a predictive model based on neural networks trained on a movements dataset acquired from several subjects with a complementary capture system. We employ a two-stage pipeline that first resolves occlusions and then recovers all joint transformations. We show that our method compares favorably to inverse kinematics by inferring automatically the constraints from the data, provides a natural reconstruction of postures, and handles occlusions better than three proposed baselines.</p></div>","PeriodicalId":52283,"journal":{"name":"Computers and Graphics: X","volume":"2 ","pages":"Article 100011"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cagx.2019.100011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90432118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Clipping simple polygons with degenerate intersections 裁剪简单多边形与退化的交叉点

Computers and Graphics: X Pub Date : 2019-12-01 DOI: 10.1016/j.cagx.2019.100007

Erich L Foster , Kai Hormann , Romeo Traian Popa

引用次数: 12

Cellpackexplorer: Interactive model building for volumetric data of complex cells Cellpackexplorer:复杂细胞体积数据的交互式模型构建

Computers and Graphics: X Pub Date : 2019-12-01 DOI: 10.1016/j.cagx.2019.100010

Magdalena Schwarzl , Ludovic Autin , Graham Johnson , Thomas Torsney-Weir , Torsten Möller

引用次数: 3

Representation of NURBS surfaces by Controlled Iterated Functions System automata 控制迭代函数系统自动机对NURBS曲面的表示

Computers and Graphics: X Pub Date : 2019-12-01 DOI: 10.1016/j.cagx.2019.100006

Lucas Morlet, Christian Gentil, Sandrine Lanquetin, Marc Neveu, Jean-Luc Baril

{"title":"Representation of NURBS surfaces by Controlled Iterated Functions System automata","authors":"Lucas Morlet, Christian Gentil, Sandrine Lanquetin, Marc Neveu, Jean-Luc Baril","doi":"10.1016/j.cagx.2019.100006","DOIUrl":"10.1016/j.cagx.2019.100006","url":null,"abstract":"<div><p>Iterated Function Systems (IFS) are a standard tool to generate fractal shapes. In a more general way, they can represent most of standard surfaces like Bézier or B-Spline surfaces known as self-similar surfaces. Controlled Iterated Function Systems (CIFS) are an extension of IFS based on automata. CIFS are basically multi-states IFS, they can handle all IFS shapes but can also manage multi self-similar shapes. For example CIFS can describe subdivision surfaces around extraordinary vertices whereas IFS cannot. Having a common CIFS formalism facilitates the development of generic methods to manage interactions (junctions, differences...) between objects of different natures.</p><p>This work focuses on a CIFS approach of Non-Uniform Rational B-Splines (NURBS) which are the main used representation of surfaces in CAGD systems. By analyzing the recursive generating process of basis functions, we prove the stationarity of NURBS computation. This implies that NURBS can be represented as a finite automaton: a CIFS. Subdivision transformations implied in the generating process are directly deduced from blossoming formulation and are expressed as a function of the initial nodal vector. We provide a method to construct the CIFS automata for NURBS of any-degree. Then NURBS-surfaces automata are deduced using a “tensor-product” of NURBS automata. This new representation of NURBS allows us to build a bridge between them and other surfaces already represented in CIFS formalism: fractals and subdivision surfaces.</p></div>","PeriodicalId":52283,"journal":{"name":"Computers and Graphics: X","volume":"2 ","pages":"Article 100006"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cagx.2019.100006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91035648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Abstract depiction of human figures in impressionist art and children’s picture books 在印象派艺术和儿童图画书中对人物的抽象描绘

Computers and Graphics: X Pub Date : 2019-06-01 DOI: 10.1016/j.cagx.2019.100002

Neil A. Dodgson

引用次数: 3

2DToonShade: A stroke based toon shading system 一个基于笔画的卡通阴影系统

Computers and Graphics: X Pub Date : 2019-06-01 DOI: 10.1016/j.cagx.2019.100003

Matis Hudon, Mairéad Grogan, Rafael Pagés, Jan Ondřej, Aljoša Smolić

引用次数: 6

Shape analysis of 3D nanoscale reconstructions of brain cell nuclear envelopes by implicit and explicit parametric representations 用隐式和显式参数表示的三维纳米级脑细胞核包膜的形状分析

Computers and Graphics: X Pub Date : 2019-06-01 DOI: 10.1016/j.cagx.2019.100004

Marco Agus , Maria Veloz Castillo , Javier F. Garnica Molina , Enrico Gobbetti , Heikki Lehväslaiho , Alex Morales Tapia , Pierre J. Magistretti , Markus Hadwiger , Corrado Calí

{"title":"Shape analysis of 3D nanoscale reconstructions of brain cell nuclear envelopes by implicit and explicit parametric representations","authors":"Marco Agus , Maria Veloz Castillo , Javier F. Garnica Molina , Enrico Gobbetti , Heikki Lehväslaiho , Alex Morales Tapia , Pierre J. Magistretti , Markus Hadwiger , Corrado Calí","doi":"10.1016/j.cagx.2019.100004","DOIUrl":"10.1016/j.cagx.2019.100004","url":null,"abstract":"<div><p>Shape analysis of cell nuclei is becoming increasingly important in biology and medicine. Recent results have identified that large variability in shape and size of nuclei has an important impact on many biological processes. Current analysis techniques involve automatic methods for detection and segmentation of histology and microscopy images, but are mostly performed in 2D. Methods for 3D shape analysis, made possible by emerging acquisition methods capable to provide nanometric-scale 3D reconstructions, are still at an early stage, and often assume a simple spherical shape. We introduce here a framework for analyzing 3D nanoscale reconstructions of nuclei of brain cells (mostly neurons), obtained by semiautomatic segmentation of electron micrographs. Our method considers two parametric representations: the first one customizes the implicit <em>hyperquadrics</em>formulation and it is particularly suited for convex shapes, while the latter considers a <em>spherical harmonics</em> decomposition of the explicit radial representation. Point clouds of nuclear envelopes, extracted from image data, are fitted to the parameterized models which are then used for performing statistical analysis and shape comparisons. We report on the analysis of a collection of 121 nuclei of brain cells obtained from the somatosensory cortex of a juvenile rat.</p></div>","PeriodicalId":52283,"journal":{"name":"Computers and Graphics: X","volume":"1 ","pages":"Article 100004"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cagx.2019.100004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90842115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8