EG2018

Permanent URI for this community

https://diglib.eg.org/handle/10.2312/2632158

Browse

Now showing 1 - 20 of 57

State of the Art on 3D Reconstruction with RGB-D Cameras
(The Eurographics Association and John Wiley & Sons Ltd., 2018) Zollhöfer, Michael; Stotko, Patrick; Görlitz, Andreas; Theobalt, Christian; Nießner, Matthias; Klein, Reinhard; Kolb, Andreas; Hildebrandt, Klaus and Theobalt, Christian
The advent of affordable consumer grade RGB-D cameras has brought about a profound advancement of visual scene reconstruction methods. Both computer graphics and computer vision researchers spend significant effort to develop entirely new algorithms to capture comprehensive shape models of static and dynamic scenes with RGB-D cameras. This led to significant advances of the state of the art along several dimensions. Some methods achieve very high reconstruction detail, despite limited sensor resolution. Others even achieve real-time performance, yet possibly at lower quality. New concepts were developed to capture scenes at larger spatial and temporal extent. Other recent algorithms flank shape reconstruction with concurrent material and lighting estimation, even in general scenes and unconstrained conditions. In this state-of-the-art report, we analyze these recent developments in RGB-D scene reconstruction in detail and review essential related work. We explain, compare, and critically analyze the common underlying algorithmic concepts that enabled these recent advancements. Furthermore, we show how algorithms are designed to best exploit the benefits of RGB-D data while suppressing their often non-trivial data distortions. In addition, this report identifies and discusses important open research questions and suggests relevant directions for future work.
EUROGRAPHICS 2018: Tutorials Frontmatter
(Eurographics Association, 2018) Ritschel, Tobias; Telea, Alexandru; Ritschel, Tobias; Telea, Alexandru
RIFNOM: 3D Rotation-Invariant Features on Normal Maps
(The Eurographics Association, 2018) Nakamura, Akihiro; Miyashita, Leo; Watanabe, Yoshihiro; Ishikawa, Masatoshi; Jain, Eakta and Kosinka, Jirí
This paper presents 3D rotation-invariant features on normal maps: RIFNOM.We assign a local coordinate system (CS) to each pixel by using neighbor normals to extract the 3D rotation-invariant features. These features can be used to perform interest point matching between normal maps. We can estimate 3D rotations between corresponding interest points by comparing local CSs. Experiments with normal maps of a rigid object showed the performance of the proposed method in estimating 3D rotations. We also applied the proposed method to a non-rigid object. By estimating 3D rotations between corresponding interest points, we successfully detected deformation of the object.
Growing Circles: A Region Growing Algorithm for Unstructured Grids and Non-aligned Boundaries
(The Eurographics Association, 2018) Dabbaghchian, Saeed; Jain, Eakta and Kosinka, Jirí
Detecting the boundaries of an enclosed region is a problem which arises in some applications such as the human upper airway modeling. Using of standard algorithms fails because of the inevitable errors, i.e. gaps and overlaps between the surrounding boundaries. Growing circles is an automatic approach to address this problem. A circle is centered inside the region and starts to grow by increasing its radius. Its growth is limited either by the surrounding boundaries or by reaching its maximum radius. To deal with complex shapes, many circles are used in which each circle partially reconstructs the region, and the whole region is determined by the union of these partial regions. The center of the circles and their maximum radius are calculated adaptively. It is similar to the region growing algorithm which is widely used in image processing applications. However, it works for unstructured grids as well as Cartesian ones. As an application of the method, it is applied to detect the boundaries of the upper airway cross-sections.
Teaching Image-Processing Programming for Mobile Devices: A Software Development Perspective
(The Eurographics Association, 2018) Trapp, Matthias; Pasewaldt, Sebastian; Dürschmid, Tobias; Semmo, Amir; Döllner, Jürgen; Post, Frits and Žára, Jirí
In this paper we present a concept of a research course that teaches students in image processing as a building block of mobile applications. Our goal with this course is to teach theoretical foundations, practical skills in software development as well as scientific working principles to qualify graduates to start as fully-valued software developers or researchers. The course includes teaching and learning focused on the nature of small team research and development as encountered in the creative industries dealing with computer graphics, computer animation and game development. We discuss our curriculum design and issues in conducting undergraduate and graduate research that we have identified through four iterations of the course. Joint scientific demonstrations and publications of the students and their supervisors as well as quantitative and qualitative evaluation by students underline the success of the proposed concept. In particular, we observed that developing using a common software framework helps the students to jump start their course projects, while industry software processes such as branching coupled with a three-tier breakdown of project features helps them to structure and assess their progress.
Halftone Pattern: A New Steganographic Approach
(The Eurographics Association, 2018) Cruz, Leandro; Patrão, Bruno; Gonçalves, Nuno; Diamanti, Olga and Vaxman, Amir
In general, an image is worth a thousand words, but sometimes, words are the most efficient tool to communicate some information. Thereupon, in this work, we will present an approach for combining the visual appeal of images with the communication power of words. Our method is a steganographic technique to hide a textual information into an image. It is inspired by the use of dithering to create halftone images. It begins from a base image and creates the coded image by associating each base image pixel to a set of two-colors pixels (halftone) forming an appropriate pattern. The coded image is a machine readable information, with good aesthetic, secure and containing data redundancy and compression. Thus, it can be used in a variety of applications.
Audio-driven Emotional Speech Animation
(The Eurographics Association, 2018) Charalambous, Constantinos; Yumak, Zerrin; Stappen, A. Frank van der; Jain, Eakta and Kosinka, Jirí
We propose a procedural audio-driven speech animation method that takes into account emotional variations in speech. Given any audio with its corresponding speech transcript, the method generates speech animation for any 3D character. The expressive speech model matches the pitch and intensity variations in audio to individual visemes. In addition, we introduce a dynamic co-articulation model that takes into account linguistic rules varying among emotions. We test our approach against two popular speech animation tools and we show that our method surpass them in a perceptual experiment.
From Spectra to Perceptual Color: Visualization Tools for the Dimensional Reduction Achieved by the Human Color Sense
(The Eurographics Association, 2018) Harvey, Joshua S.; Siviour, Clive R.; Smithson, Hannah E.; Jain, Eakta and Kosinka, Jirí
Physical colors, defined as unique combinations of photon populations whose wavelengths lie in the visible range, occupy an infinite-dimensional real Hilbert space. Any number of photon populations from the continuous spectrum of monochromatic wavelengths may be present to any positive amount. For normal vision, this space collapses to three dimensions at the retina, with any physical color eliciting just three sensor values corresponding to the excitations of the three classes of cone photoreceptor cells. While there are many mappings and visualizations of three-dimensional perceptual color space, attempts to visualize the relationship between infinite-dimensional physical color space and perceptual space are lacking. We present a visualization framework to illustrate this mathematical relation, using animation and transparency to map multiple physical colors to locations in perceptual space, revealing how the perceptual color solid can be understood as intersecting surfaces and volumes. This framework provides a clear and intuitive illustration of color metamerism.
Arm Swinging vs Treadmill: A Comparison Between Two Techniques for Locomotion in Virtual Reality
(The Eurographics Association, 2018) Calandra, Davide; Billi, Michele; Lamberti, Fabrizio; Sanna, Andrea; Borchiellini, Romano; Diamanti, Olga and Vaxman, Amir
When it comes to locomotion in Virtual Reality (VR), a wide range of different techniques has been proposed in the scientific literature or as commercial products. However, the best choice for a specific application is still not immediate, being each technique characterized by different advantages and drawbacks. The present work reports on the results of a user study-based comparison between two methods: a locomotion treadmill, which supports omni-directional movements through walking in place over a hardware device, and Arm Swinging, which recognizes movement from the swinging back and forth of the user's arms (e.g., gathered by sensors embedded in hand controllers). Experiments have been carried out in a realistic immersive VR scenario, which requested users to respond to a fire emergency in a road tunnel by moving and interacting with the environment.
A Multifragment Renderer for Material Aging Visualization
(The Eurographics Association, 2018) Adamopoulos, Georgios; Moutafidou, Anastasia; Drosou, Anastasios; Tzovaras, Dimitrios; Fudos, Ioannis; Jain, Eakta and Kosinka, Jirí
People involved in curatorial work and in preservation/conservation tasks need to understand exactly the nature of aging and to prevent it with minimal preservation work. In this scenario, it is of extreme importance to have tools to produce and visualize digital representations and models of visual surface appearance and material properties, to help the scientist understand how they evolve over time and under particular environmental conditions. We report on the development of a multifragment renderer for visualizing and combining the results of simulated aging of artwork objects. Several natural aging processes manifest themselves through change of color, fading, deformations or cracks. Furthermore, changes in the materials underneath the visible layers may be detected or simulated.
Incorporating Visualization Research in Introductory Programming Course: Case Studies
(The Eurographics Association, 2018) Kim, Sunghee; Post, Frits and Žára, Jirí
The importance of early research experience for undergraduate students has been stressed time and time again. This paper presents three case studies in which non-CS major students could gain a visualization research experience in their first programming course. In all case studies, students were given real climate data to visualize. In the first case study, students visualized spatial correlation between two variables (weather conditions) on a map so that viewers could infer areas in which the two variables were highly correlated in a positive or negative way, or areas with little to no correlation. In the second and third case studies, students generated single variable visualization and multidimensional visualization of two or four variables. In each of the three case studies the students were led through the process of understanding data, exploring different representations, and designing and implementing an agreed-upon visual representation. Increased number of students decided to take the next course in Computer Science compared to previous years without a research project. Feedback from the students suggests that they enjoyed using data they could understand and found the process and the final product rewarding and applicable to projects in their major and courses.
Recent Advances in Projection Mapping Algorithms, Hardware and Applications
(The Eurographics Association and John Wiley & Sons Ltd., 2018) Grundhöfer, Anselm; Iwai, Daisuke; Hildebrandt, Klaus and Theobalt, Christian
This State-of-the-Art-Report covers the recent advances in research fields related to projection mapping applications. We summarize the novel enhancements to simplify the 3D geometric calibration task, which can now be reliably carried out either interactively or automatically using self-calibration methods. Furthermore, improvements regarding radiometric calibration and compensation as well as the neutralization of global illumination effects are summarized. We then introduce computational display approaches to overcome technical limitations of current projection hardware in terms of dynamic range, refresh rate, spatial resolution, depth-of-field, view dependency, and color space. These technologies contribute towards creating new application domains related to projection-based spatial augmentations. We summarize these emerging applications, and discuss new directions for industries.
Creating New Chinese Fonts based on Manifold Learning and Adversarial Networks
(The Eurographics Association, 2018) Guo, Yuan; Lian, Zhouhui; Tang, Yingmin; Xiao, Jianguo; Diamanti, Olga and Vaxman, Amir
The design of fonts, especially Chinese fonts, is known as a tough task that requires considerable time and professional skills. In this paper, we propose a method to easily generate Chinese font libraries in new styles based on manifold learning and adversarial networks. Starting from a number of existing fonts that cover various styles, we firstly use convolutional neural networks to obtain the representation features of these fonts, and then build a font manifold via non-linear mapping. Using the font manifold, we can interpolate and move between those existing fonts to get new font features, which are then fed into a generative network learned via adversarial training to generate the whole new font libraries. Experimental results demonstrate that high-quality Chinese fonts in various new styles against existing ones can be efficiently generated using our method.
A Drink in Mars: an Approach to Distributed Reality
(The Eurographics Association, 2018) Perez, Pablo; Gonzalez-Sosa, Ester; Kachach, Redouane; Ruiz, Jaime Jesus; Villegas, Alvaro; Jain, Eakta and Kosinka, Jirí
We have developed A Drink in Mars application as a proof of concept of Distributed Reality, a particularisation of Mixed Reality which combines a reality transmitted from a remote place (e.g. live immersive video stream from Mars) with user interaction with the local reality (e.g. drink their favourite beverage). The application shows acceptable immersion and local interactivity. It runs on Samsung GearVR and needs no special green room for chroma keying, thus being suitable to test different use cases.
Presenting a Deep Motion Blending Approach for Simulating Natural Reach Motions
(The Eurographics Association, 2018) Gaisbauer, Felix; Froehlich, Philipp; Lehwald, Jannes; Agethen, Philipp; Rukzio, Enrico; Jain, Eakta and Kosinka, Jirí
Motion blending and character animation systems are widely used in different domains such as gaming or simulation within production industries. Most of the established approaches are based on motion blending techniques. These approaches provide natural motions within common scenarios while inducing low computational costs. However, with increasing amount of influence parameters and constraints such as collision-avoidance, they increasingly fail or require a vast amount of time to meet these requirements. With ongoing progress in artificial intelligence and neural networks, recent works present deep learning based approaches for motion synthesis, which offer great potential for modeling natural motions, while considering heterogeneous influence factors. In this paper, we propose a novel deep blending approach to simulate non-cyclical natural reach motions based on an extension of phase functioned deep neural networks.
Optimized Sampling for View Interpolation in Light Fields with Overlapping Patches
(The Eurographics Association, 2018) Schedl, David C.; Bimber, Oliver; Diamanti, Olga and Vaxman, Amir
Optimized sampling masks that reduce the complexity of camera arrays while preserving the quality of light fields captured at high directional sampling resolution are presented. We propose a new quality metric that is based on sampling-theoretic considerations, a new mask estimation approach that reduces the search space by applying regularity and symmetry constraints, and an enhanced upsampling technique using compressed sensing that supports maximal patch overlap. Our approach out-beats state-of-the-art view-interpolation techniques for light fields and does not rely on depth reconstruction.
Deep Learning for Graphics
(The Eurographics Association, 2018) Mitra, Niloy J.; Ritschel, Tobias; Kokkinos, Iasonas; Guerrero, Paul; Kim, Vladimir; Rematas, Konstantinos; Yumer, Ersin; Ritschel, Tobias and Telea, Alexandru
In computer graphics, many traditional problems are now better handled by deep-learning based data-driven methods. In applications that operate on regular 2D domains, like image processing and computational photography, deep networks are state-of-the-art, beating dedicated hand-crafted methods by significant margins. More recently, other domains such as geometry processing, animation, video processing, and physical simulations have benefited from deep learning methods as well. The massive volume of research that has emerged in just a few years is often difficult to grasp for researchers new to this area. This tutorial gives an organized overview of core theory, practice, and graphics-related applications of deep learning.
Exemplar Based Filtering of 2.5D Meshes of Faces
(The Eurographics Association, 2018) Dihl, Leandro; Cruz, Leandro; Gonçalves, Nuno; Jain, Eakta and Kosinka, Jirí
In this work, we present a content-aware filtering for 2.5D meshes of faces. We propose an exemplar-based filter that corrects each point of a given mesh through local model-exemplar neighborhood comparison. We take advantage of prior knowledge of the models (faces) to improve the comparison. We first detect facial feature points, and create the point correctors for regions of each feature, and only use the correspondent regions for correcting a point of the filtered mesh.
EUROGRAPHICS 2018: Short Papers Frontmatter
(Eurographics Association, 2018) Diamanti, Olga; Vaxman, Amir; Diamanti, Olga; Vaxman, Amir
Accelerating Sphere Tracing
(The Eurographics Association, 2018) Bálint, Csaba; Valasek, Gábor; Diamanti, Olga and Vaxman, Amir
This paper presents two performance improvements on sphere tracing. First, a sphere tracing variant designed to take optimal step sizes near planar surfaces is proposed. We demonstrate how relaxation is used to make this method applicable to sphere tracing arbitrary geometries and compare its performance to classical (by Hart) and relaxed (Keinert et al.) sphere tracing in rendering various scenes. The method is also general in the sense that it can be applied in any scenario that requires the computation of ray-surface intersections. Our second contribution is a multi-resolution rendering strategy that can be used with any sphere tracing variant. By starting from a lower resolution and gradually increasing it, render times can be reduced.

Browse

Browsing EG2018 by Issue Date

Results Per Page

Sort Options