@article {CGF:CGF12612, author = {Byška, J. and Jurčík, A. and Gröller, M. E. and Viola, I. and Kozlíková, B.}, title = {MoleCollar and Tunnel Heat Map Visualizations for Conveying Spatio-Temporo-Chemical Properties Across and Along Protein Voids}, journal = {Computer Graphics Forum}, volume = {34}, number = {3}, issn = {1467-8659}, url = {http://dx.doi.org/10.1111/cgf.12612}, doi = {10.1111/cgf.12612}, pages = {1--10}, keywords = {Categories and Subject Descriptors (according to ACM CCS), I.3.6 [Computer Graphics]: Picture/Image Generation—Line and curve generation}, year = {2015}, abstract = {Studying the characteristics of proteins and their inner void space, including their geometry, physico-chemical properties and dynamics are instrumental for evaluating the reactivity of the protein with other small molecules. The analysis of long simulations of molecular dynamics produces a large number of voids which have to be further explored and evaluated. In this paper we propose three new methods: two of them convey important properties along the long axis of a selected void during molecular dynamics and one provides a comprehensive picture across the void. The first two proposed methods use a specific heat map to present two types of information: an overview of all detected tunnels in the dynamics and their bottleneck width and stability over time, and an overview of a specific tunnel in the dynamics showing the bottleneck position and changes of the tunnel length over time. These methods help to select a small subset of tunnels, which are explored individually and in detail. For this stage we propose the third method, which shows in one static image the temporal evolvement of the shape of the most critical tunnel part, i.e., its bottleneck. This view is enriched with abstract depictions of different physicochemical properties of the amino acids surrounding the bottleneck. The usefulness of our newly proposed methods is demonstrated on a case study and the feedback from the domain experts is included. The biochemists confirmed that our novel methods help to convey the information about the appearance and properties of tunnels in a very intuitive and comprehensible manner.}, images = {images/cgf12612-fig-0001.png}, thumbnails = {images/cgf12612-fig-0001.png} } @misc{Stoppel2015ConfReport, author = {Sergej Stoppel}, title = {Conference Report IEEE VIS 2014}, year = {2015}, month = {January}, abstract = { Conference report about the IEEE VIS 2014 in Paris.}, url = {http://www.norsigd.no/norsigd_info/nsi-1-15.pdf}, images = {images/Shneiderman_Gerson_Pushups.PNG}, thumbnails = {images/Shneiderman_Gerson_Pushups.PNG} } @misc{Hauser2015SUBSEA, author = {Helwig Hauser}, title = {Big Data - visualization and visual analytics}, year = {2015}, month = {March}, day = {19}, howpublished = {Invited talk at the NCE Subsea Forum}, abstract = {}, location = {Bergen, Norway}, images = {images/ThumbnailBigData.jpg}, thumbnails = {images/ThumbnailBigData.jpg}, pdf = {pdfs/2015-03-19--NCE--BigDataVA--print2up.pdf} } @misc{Hauser2015VIS, author = {Helwig Hauser}, title = {From Anatomy to Physiology in Medical Visualization}, year = {2015}, month = {October}, day = {25}, howpublished = {Tutorial talk at IEEE VIS 2015}, abstract = {Generally, medical visualization assists the diagnosis of diseases as well as the treatment of patients. Capturing the patients anatomy, which to a large degree is in the focus of traditional MedViz, certainly is one important key to the success of medical visualization. At least equally important, if not even more, is the consideration of physiology, entailing the complex of function (or malfunction) of the patient. Modern imaging modalities extend beyond the simple depiction of static anatomical snapshots to capturing temporal processes as well as to covering multiple scales of physiology eventually linking molecular biology to medicine. The visualization of human physiology complements other techniques, for example lab tests for quantifying certain physiological functions. We deem ourselves at the beginning of an interesting extension of MedViz research to increasingly capture physiology in addition to anatomy.}, location = {Chicago, Illinois, USA}, images = {images/ThumbnailVisTut.png}, thumbnails = {images/ThumbnailVisTut.png}, pdf = {pdfs/2015-10-25--VIS2015--TutTalkHH--print2up.pdf} } @misc{Hauser2015IRIS, author = {Helwig Hauser}, title = {Medical Visualization Research at the VisGroup @ UiB.no/ii}, year = {2015}, month = {November}, day = {25}, howpublished = {Invited talk at IRIS}, abstract = {Established about eight years ago, the Visualization Research Group is the youngest of six research groups at the Department of Informatics, UiB, focusing on application-oriented basic research in visualization. Medicine and related disciplines (such as biomedicine, biology, etc.) stand for a growing number of grand visualization challenges and the vivid interdisciplinary MedViz network in Bergen gives ample opportunities for internationally recognized visualization research. In this talk, an overview of the visualization research group [1] is given, together with a short review of selected research projects in medical visualization.}, location = {Bergen, Norway}, images = {images/ThumbNailIRIS.jpg}, thumbnails = {images/ThumbNailIRIS.jpg}, pdf = {pdfs/2015-11-25--PresAtIRIS--print2up.pdf} } @INPROCEEDINGS{Mindek-2015-ASM, author = {Peter Mindek and Ladislav \v{C}mol{\'i}k and Ivan Viola and M. Eduard Gr{\"o}ller and Stefan Bruckner}, title = {Automatized Summarization of Multiplayer Games}, booktitle = {Proceedings of SCCG 2015}, year = {2015}, pages = {93--100}, month = apr, note = {SCCG 2015 Best Paper Award}, abstract = {We present a novel method for creating automatized gameplay dramatization of multiplayer video games. The dramatization serves as a visual form of guidance through dynamic 3D scenes with multiple foci, typical for such games. Our goal is to convey interesting aspects of the gameplay by animated sequences creating a summary of events which occurred during the game. Our technique is based on processing many cameras, which we refer to as a flock of cameras, and events captured during the gameplay, which we organize into a so-called event graph. Each camera has a lifespan with a certain time interval and its parameters such as position or look-up vector are changing over time. Additionally, during its lifespan each camera is assigned an importance function, which is dependent on the significance of the structures that are being captured by the camera. The images captured by the cameras are composed into a single continuous video using a set of operators based on cinematographic effects. The sequence of operators is selected by traversing the event graph and looking for specific patterns corresponding to the respective operators. In this way, a large number of cameras can be processed to generate an informative visual story presenting the gameplay. Our compositing approach supports insets of camera views to account for several important cameras simultaneously. Additionally, we create seamless transitions between individual selected camera views in order to preserve temporal continuity, which helps the user to follow the virtual story of the gameplay.}, keywords = {animation, storytelling, game visualization}, location = {Smolenice, Slovakia}, owner = {bruckner}, timestamp = {2015.06.08}, url = {http://www.cg.tuwien.ac.at/research/publications/2015/mindek-2015-mc/}, images = {images/Mindek-2015-ASM.jpg}, thumbnails = {images/Mindek-2015-ASM.jpg} } @ARTICLE{Karimov-2015-GVE, author = {Alexey Karimov and Gabriel Mistelbauer and Thomas Auzinger and Stefan Bruckner}, title = {Guided Volume Editing based on Histogram Dissimilarity}, journal = {Computer Graphics Forum}, year = {2015}, volume = {34}, pages = {91--100}, number = {3}, month = may, abstract = {Segmentation of volumetric data is an important part of many analysis pipelines, but frequently requires manual inspection and correction. While plenty of volume editing techniques exist, it remains cumbersome and error-prone for the user to find and select appropriate regions for editing. We propose an approach to improve volume editing by detecting potential segmentation defects while considering the underlying structure of the object of interest. Our method is based on a novel histogram dissimilarity measure between individual regions, derived from structural information extracted from the initial segmentation. Based on this information, our interactive system guides the user towards potential defects, provides integrated tools for their inspection, and automatically generates suggestions for their resolution. We demonstrate that our approach can reduce interaction effort and supports the user in a comprehensive investigation for high-quality segmentations.}, doi = {10.1111/cgf.12621}, event = {EuroVis 2015}, keywords = {medical visualization, segmentation, volume editing, interaction}, location = {Cagliari, Italy}, owner = {bruckner}, timestamp = {2015.06.08}, url = {http://www.cg.tuwien.ac.at/research/publications/2015/karimov-2015-HD/}, images = {images/Karimov-2015-GVE.png}, thumbnails = {images/Karimov-2015-GVE.png} } @ARTICLE{Diehl-2015-VAS, author = {Alexandra Diehl and Leandro Pelorosso and Claudio Delrieux and Celeste Saulo and Juan Ruiz and M. Eduard Gr{\"o}ller and Stefan Bruckner}, title = {Visual Analysis of Spatio-Temporal Data: Applications in Weather Forecasting}, journal = {Computer Graphics Forum}, year = {2015}, volume = {34}, pages = {381--390}, number = {3}, month = may, abstract = {Weather conditions affect multiple aspects of human life such as economy, safety, security, and social activities. For this reason, weather forecast plays a major role in society. Currently weather forecasts are based on Numerical Weather Prediction (NWP) models that generate a representation of the atmospheric flow. Interactive visualization of geo-spatial data has been widely used in order to facilitate the analysis of NWP models. This paper presents a visualization system for the analysis of spatio-temporal patterns in short-term weather forecasts. For this purpose, we provide an interactive visualization interface that guides users from simple visual overviews to more advanced visualization techniques. Our solution presents multiple views that include a timeline with geo-referenced maps, an integrated webmap view, a forecast operation tool, a curve-pattern selector, spatial filters, and a linked meteogram. Two key contributions of this work are the timeline with geo-referenced maps and the curve-pattern selector. The latter provides novel functionality that allows users to specify and search for meaningful patterns in the data. The visual interface of our solution allows users to detect both possible weather trends and errors in the weather forecast model.We illustrate the usage of our solution with a series of case studies that were designed and validated in collaboration with domain experts.}, doi = {10.1111/cgf.12650}, event = {EuroVis 2015}, keywords = {weather forecasting, visual analysis, spatiotemporal data}, location = {Cagliari, Italy}, owner = {bruckner}, images = {images/Diehl-2015-VAS.jpg}, thumbnails = {images/Diehl-2015-VAS.jpg} } @ARTICLE{Angelelli-2015-PQA, author = {Paolo Angelelli and Stefan Bruckner}, title = {Performance and Quality Analysis of Convolution-Based Volume Illumination}, journal = {Journal of WSCG}, year = {2015}, volume = {23}, pages = {131--138}, number = {2}, month = jun, abstract = {Convolution-based techniques for volume rendering are among the fastest in the on-the-fly volumetric illumination category. Such methods, however, are still considerably slower than conventional local illumination techniques. In this paper we describe how to adapt two commonly used strategies for reducing aliasing artifacts, namely pre-integration and supersampling, to such techniques. These strategies can help reduce the sampling rate of the lighting information (thus the number of convolutions), bringing considerable performance benefits. We performance improvements. We also analyze the (negligible) differences they introduce when comparing their output to the reference method. These strategies can be highly beneficial in setups where direct volume rendering of continuously streaming data is desired and continuous recomputation of full lighting information is too expensive, or where memory constraints make it preferable not to keep additional precomputed volumetric data in memory. In such situations these strategies make single pass, convolution-based volumetric illumination models viable for a broader range of applications, and this paper provides practical guidelines for using and tuning such strategies to specific use cases.}, keywords = {volume rendering, global illumination, scientific visualization, medical visualization}, images = {images/Angelelli-2015-PQA.png}, thumbnails = {images/Angelelli-2015-PQA.png} } @inproceedings{splechtna2015interactive, title={Interactive visual steering of hierarchical simulation ensembles}, author={Splechtna, Rainer and Matkovic, Kresimir and Gracanin, Denis and Jelovic, Mario and Hauser, Helwig}, booktitle={Visual Analytics Science and Technology (VAST), 2015 IEEE Conference on}, pages={89--96}, year={2015}, organization={IEEE}, doi = {10.1109/VAST.2015.7347635}, abstract = {Multi-level simulation models, i.e., models where different components are simulated using sub-models of varying levels of complexity, belong to the current state-of-the-art in simulation. The existing analysis practice for multi-level simulation results is to manually compare results from different levels of complexity, amounting to a very tedious and error-prone, trial-and-error exploration process. In this paper, we introduce hierarchical visual steering, a new approach to the exploration and design of complex systems. Hierarchical visual steering makes it possible to explore and analyze hierarchical simulation ensembles at different levels of complexity. At each level, we deal with a dynamic simulation ensemble - the ensemble grows during the exploration process. There is at least one such ensemble per simulation level, resulting in a collection of dynamic ensembles, analyzed simultaneously. The key challenge is to map the multi-dimensional parameter space of one ensemble to the multi-dimensional parameter space of another ensemble (from another level). In order to support the interactive visual analysis of such complex data we propose a novel approach to interactive and semi-automatic parameter space segmentation and comparison. The approach combines a novel interaction technique and automatic, computational methods - clustering, concave hull computation, and concave polygon overlapping - to support the analysts in the cross-ensemble parameter space mapping. In addition to the novel parameter space segmentation we also deploy coordinated multiple views with standard plots. We describe the abstract analysis tasks, identified during a case study, i.e., the design of a variable valve actuation system of a car engine. The study is conducted in cooperation with experts from the automotive industry. Very positive feedback indicates the usefulness and efficiency of the newly proposed approach.}, images = {images/ThumbNailIMG--HierSteering.png}, thumbnails = {images/ThumbNailIMG--HierSteering.png} } @Inproceedings{PB-VRVis-2015-026, author = {Matkovic, K and Gracanin, D and Jelovi{\'{c}}, M and Hauser, H}, title = {Interactive Visual Analysis of Large Simulation Ensembles}, year = {2015}, booktitle = {Proceedings of Winter Simulation Conference (WSC 2015, to appear)}, abstract = {Recent advancements in simulation and computing make it possible to compute large simulation ensembles. A simulation ensemble consists of multiple simulation runs of the same model with different values of control parameters. In order to cope with ensemble data, a modern analysis methodology is necessary. In this paper, we present our experience with simulation ensemble exploration and steering by means of interactive visual analysis. We describe our long-term collaboration with fuel injection experts from the automotive industry. We present how interactive visual analysis can be used to gain a deep understanding in the ensemble data, and how it can be used, in a combination with automatic methods, to steer the ensemble creation, even for very complex systems. Very positive feedback from domain experts motivated us, a team of visualization and simulation experts, to present this research to the simulation community.}, images = {images/ThumbNailIMG--EnsembleIVA.png}, thumbnails = {images/ThumbNailIMG--EnsembleIVA.png} } @inproceedings{alsallakh2015state, title={The State-of-the-Art of Set Visualization}, author={Alsallakh, Bilal and Micallef, Luana and Aigner, Wolfgang and Hauser, Helwig and Miksch, Silvia and Rodgers, Peter}, booktitle={Computer Graphics Forum}, year={2015}, organization={Wiley Online Library}, abstract = {Sets comprise a generic data model that has been used in a variety of data analysis problems. Such problems involve analysing and visualizing set relations between multiple sets defined over the same collection of elements. However, visualizing sets is a non-trivial problem due to the large number of possible relations between them. We provide a systematic overview of state-of-the-art techniques for visualizing different kinds of set relations. We classify these techniques into six main categories according to the visual representations they use and the tasks they support. We compare the categories to provide guidance for choosing an appropriate technique for a given problem. Finally, we identify challenges in this area that need further research and propose possible directions to address these challenges. Further resources on set visualization are available at http://www.setviz.net.}, doi = {10.1111/cgf.12722}, images = {images/ThumbNailIMG--SetVisSTAR.png}, thumbnails = {images/ThumbNailIMG--SetVisSTAR.png} } @inproceedings{cellVIEW_2015, title = "cellVIEW: a Tool for Illustrative and Multi-Scale Rendering of Large Biomolecular Datasets", author = "Mathieu Le Muzic and Ludovic Autin and Julius Parulek and Ivan Viola", year = "2015", abstract = "In this article we introduce cellVIEW, a new system to interactively visualize large biomolecular datasets on the atomic level. Our tool is unique and has been specifically designed to match the ambitions of our domain experts to model and interactively visualize structures comprised of several billions atom. The cellVIEW system integrates acceleration techniques to allow for real-time graphics performance of 60 Hz display rate on datasets representing large viruses and bacterial organisms. Inspired by the work of scientific illustrators, we propose a level-of-detail scheme which purpose is two-fold: accelerating the rendering and reducing visual clutter. The main part of our datasets is made out of macromolecules, but it also comprises nucleic acids strands which are stored as sets of control points. For that specific case, we extend our rendering method to support the dynamic generation of DNA strands directly on the GPU. It is noteworthy that our tool has been directly implemented inside a game engine. We chose to rely on a third party engine to reduce software development work-load and to make bleeding-edge graphics techniques more accessible to the end-users. To our knowledge cellVIEW is the only suitable solution for interactive visualization of large bimolecular landscapes on the atomic level and is freely available to use and extend.", month = sep, booktitle = "EG Workshop on Visual Computing for Biology and Medicine", project = {physioillustration}, images = {images/cellview2015.png}, thumbnails = {images/cellview2015.png}, } @misc{Hauser2015Austria, author = {Helwig Hauser}, title = {Integrating Spatial & Non-spatial Data in Visualization}, year = {2015}, month = {October}, howpublished = {Invited talk}, abstract = {New opportunities in data science, such as the consideration of cohort study data, require new approaches to the appropriate design of an effective visualization. We need to capitalize on successful solutions from previous research, of course, but we should also explore new strategies that challenge our already established mindset in visualization. In this talk, I address the specific challenge of integrating spatial and non-spatial data in visualization, in particular, when the spatial aspect of the data is of great importance to the user---this could relate to the morphological information in a 3D medical scan or the geometrical aspects of flow features in a CFD simulation. In data visualizaiton, the actual mapping step---from data to a visual form---is certainly crucial and we should strive to optimally exploit the great opportunities that we have in designing this step. In data-intensive sciences, the study objects of interest are increasingly often represented by extensive and rich datasets (aka. big data)---while traditionally the focus of visualization was on individual, static datasets, we now face dynamic data, representing entire ensembles of study entities, etc. Visualization gets a lot harder, when facing such new "big data" challenges---both on the designer sider as well as also on the user side. At the same time, however, also the potential for impact is increasing, which amounts to a fantastic motivation for new basic research in visualization.}, location = {Vienna, Austria}, images = {images/ThumbPicHHAustria2015.png}, thumbnails = {images/ThumbPicHHAustria2015.png}, pdf = {pdfs/2015-10-14--HHauser--InvTalk--print--2up.pdf}, } @article{Brambilla15Expressive, author = {Andrea Brambilla and Helwig Hauser}, title = {Expressive Seeding of Multiple Stream Surfaces for Interactive Flow Exploration}, journal={Computers \& Graphics}, volume={47}, pages={123--134}, year = {2015}, publisher={Elsevier}, doi = {http://dx.doi.org/10.1016/j.cag.2015.01.002}, url = {http://www.sciencedirect.com/science/article/pii/S0097849315000035}, abstract = { Integral surfaces, such as stream and path surfaces, are highly effective in the context of the exploration and the analysis of the long-term behavior of three-dimensional flows. However, specifying the seeding curves that lead to an expressive set of integral surfaces is a challenging and cumbersome task. In this paper, we propose an algorithm for automatically seeding multiple stream surfaces around a user-specified location of interest. The process is guided by a streamline similarity measure. Within the resulting integral surfaces, adjacent streamlines are as similar as possible to each other. In addition, we aim at conveying different aspects of the flow behavior with each surface. This is achieved by maximizing the dissimilarity between streamlines from different stream surfaces. The capabilities of our technique are demonstrated on a number of application cases. We provide a qualitative comparison with two state-of-the-art approaches. We report from our detailed exchange with a domain expert concerning the expressiveness and usefulness of our approach. A thorough analysis of the few parameters involved is provided. }, keywords = {Flow visualization; Stream surface selection; Visibility management}, images = {images/Brambilla15Expressive01.png, images/Brambilla15Expressive02.png}, thumbnails = {images/Brambilla15Expressive01_thumb.png, images/Brambilla15Expressive02_thumb.png}, } @inproceedings {eurovisstar20151112, booktitle = {Eurographics Conference on Visualization (EuroVis) - STARs}, editor = {R. Borgo and F. Ganovelli and I. Viola}, title = {Visualization of Biomolecular Structures: State of the Art}, author = {Kozlikova, Barbora and Krone, Michael and Lindow, Norbert and Falk, Martin and Baaden, Marc and Baum, Daniel and Viola, Ivan and Parulek, Julius and Hege, Hans-Christian}, year = {2015}, publisher = {The Eurographics Association}, DOI = {10.2312/eurovisstar.20151112}, journal = {-}, abstract = {Structural properties of molecules are of primary concern in many fields. This report provides a comprehensive overview on techniques that have been developed in the fields of molecular graphics and visualization with a focus on applications in structural biology. The field heavily relies on computerized geometric and visual representations of three-dimensional, complex, large, and time-varying molecular structures. The report presents a taxonomy that demonstrates which areas of molecular visualization have already been extensively investigated and where the field is currently heading. It discusses visualizations for molecular structures, strategies for efficient display regarding image quality and frame rate, covers different aspects of level of detail, and reviews visualizations illustrating the dynamic aspects of molecular simulation data. The report concludes with an outlook on promising and important research topics to enable further success in advancing the knowledge about interaction of molecular structures.}, volume = {-}, number = {-}, keywords = {-}, project = {physioillustration}, images = {images/molvis_star.png}, thumbnails = {images/molvis_star.png} } @INPROCEEDINGS{7156384, author={Le Muzic, Mathieu and Waldner, Manuela and Parulek, Julius and Viola, Ivan}, booktitle={Visualization Symposium (PacificVis), 2015 IEEE Pacific}, title={Illustrative Timelapse: A technique for illustrative visualization of particle-based simulations}, year={2015}, month={April}, pages={247-254}, keywords={Biological system modeling;Data models;Data visualization;Lenses;Trajectory;Videos;Visualization;I.3.7 [COMPUTER GRAPHICS]: Three-Dimensional Graphics and Realism—Animation;I.6.3 [SIMULATION AND MODELING]: Applications—}, doi={10.1109/PACIFICVIS.2015.7156384}, images = {images/illustrative_timelapse.png}, thumbnails = {images/illustrative_timelapse.png}, project = {physioillustration}, abstract = {Animated movies are a popular way to communicate complex phenomena in cell biology to the broad audience. Animation artists apply sophisticated illustration techniques to communicate a story, while trying to maintain a realistic representation of a complex dynamic environment. Since such hand-crafted animations are time-consuming and cost-intensive to create, our goal is to formalize illustration techniques used by artists to facilitate the automatic creation of visualizations generated from mesoscale particle-based molecular simulations. Our technique Illustrative Timelapse supports visual exploration of complex biochemical processes in dynamic environments by (1) seamless temporal zooming to observe phenomena in different temporal resolutions, (2) visual abstraction of molecular trajectories to ensure that observers are able to visually follow the main actors, (3) increased visual focus on events of interest, and (4) lens effects to preserve a realistic representation of the environment in the context. Results from a first user study indicate that visual abstraction of trajectories improves the ability to follow a story and is also appreciated by users. Lens effects increased the perceived amount of molecular motion in the environment while trading off traceability of individual molecules.} }