Publications

2017 [ nach oben ]

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  Reducing Visual Complexity in Software Maps using Importance-based Aggregation of Nodes. Limberger, Daniel; Scheibel, Willy; Hahn, Sebastian; Döllner, Jürgen in Proceedings of the 8th International Conference on Information Visualization Theory and Applications (2017).
  [ BibTeX ] [ Details ]
   
  @incollection{LSHD2017, abstract = {Depicting massive software system data using software maps can result in visual clutter and increased cognitive load. This paper introduces an adaptive level-of-detail (LoD) technique that uses scoring for interactive aggregation on a per-node basis. The scoring approximates importance by degree-of-interest measures as well as screen and user-interaction scores. The technique adheres to established aggregation guidelines and was evaluated by means of two user studies. The first user study investigates task completion time in visual search. The second evaluates the readability of the presented nesting level contouring for aggregates. With the adap- tive LoD technique software maps allow for multi-resolution depictions of software system information. It facilitates efficient identification of important nodes and allows for additional annotation. © The Authors 2017. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the 8th International Conference on Information Visualization Theory and Applications (IVAPP 2017).}, author = {Limberger, Daniel and Scheibel, Willy and Hahn, Sebastian and Döllner, Jürgen}, booktitle = {Proceedings of the 8th International Conference on Information Visualization Theory and Applications}, series = {IVAPP 2017}, title = {Reducing Visual Complexity in Software Maps using Importance-based Aggregation of Nodes}, year = 2017 }
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  Hybrid-Treemap Layouting. Hahn, Sebastian; Döllner, Jürgen (2017).
  [ BibTeX ] [ Details ]
   
  @inproceedings{HD2017, abstract = {This paper presents an approach for hybrid treemaps, which applies and combines several different layout principles within a single tree map in contrast to traditional treemap variants based on a single layout concept. To this end, we analyze shortcomings of state-of-the-art treemap algorithms such as Moore, Voronoi and Strip layouts. Based on a number of identified edge cases, we propose a combination of these different layout algorithms, individually selected for and applied on each sub-hierarchy of the given treemap data. The selection decision is based on the number of items to be layouted as well as the aspect-ratio of the containing visual elements. Futhermore, a layout quality score based on existing treemap layout metrics (e.g., average distance change, relative direction change, average aspect ratio) has been used to evaluate the results of the proposed hybrid layout algorithm and to demonstrate its usefulness applied on representative hierarchical data sets. © The Authors 2017. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the EuroVis2017.}, author = {Hahn, Sebastian and Döllner, Jürgen}, booktitle = {Proceedings of EuroVis 2017 - Short Papers}, month = 6, title = {Hybrid-Treemap Layouting}, year = 2017 }
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  Attributed Vertex Clouds. Scheibel, Willy; Buschmann, Stefan; Trapp, Matthias; Döllner, Jürgen in GPU Zen, C. Oat (red.) (2017). (8 ed)
  [ BibTeX ] [ Details ]
   
  @inbook{SBTD2017, abstract = {In todays computer graphics applications, large 3D scenes are rendered which consist of polygonal geometries such as triangle meshes. Using state- of-the-art techniques, this geometry is often represented on the GPU using vertex and index buffers, as well as additional auxiliary data such as tex- tures or uniform buffers. For polygonal meshes of arbitrary complexity, the described approach is indispensable. However, there are several types of simpler geometries (e.g., cuboids, spheres, tubes, or splats) that can be generated procedurally. We present an efficient data representation and render- ing concept for such geometries, denoted as attributed vertex clouds (AVCs). Using this approach, geometry is generated on the GPU during execution of the programmable rendering pipeline. Each vertex is used as the argument for a function that procedurally generates the target geometry. This function is called a transfer function, and it is implemented using shader programs and therefore executed as part of the rendering process. This approach allows for compact geometry representation and results in reduced memory footprints in comparison to traditional representations. By shifting geometry generation to the GPU, the resulting volatile geometry can be controlled flexibly, i.e., its position, parameteri- zation, and even the type of geometry can be modified without requiring suggests improved rendering times and reduced memory transmission through the rendering pipeline.}, author = {Scheibel, Willy and Buschmann, Stefan and Trapp, Matthias and Döllner, Jürgen}, booktitle = {GPU Zen}, edition = 8, editor = {Oat, Christopher}, institution = {Hasso Plattner Institute, University of Potsdam}, month = 3, publisher = {Wolfgang Engel}, series = {GPU Pro}, title = {Attributed Vertex Clouds}, year = 2017 }
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  Relative Direction Change: A Topology-based Metric for Layout Stability in Treemaps. Hahn, Sebastian; Bethge, Joseph; Döllner, Jürgen (2017).
  [ BibTeX ] [ Details ]
   
  @inproceedings{HBD2017, abstract = {This paper presents a topology-based metric for layout stability in treemaps—the Relative Direction Change (RDC). The presented metric considers the adjacency and arrangement of single shapes in a treemap, and allows for a rotation-invariant description of layout changes between two snapshots of a dataset depicted with treemaps. A user study was conducted that shows the applicability of the Relative Direction Change in comparison and addition to established layout metrics, such as Average Distance Change (ADC) and Average Aspect Ratio (AAR), with respect to human perception of treemaps. This work contributes to the establishment of a more precise model for the replicable and reliable comparison of treemap layout algorithms © The Authors 2017. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the 8th International Conference on Information Visualization Theory and Applications (IVAPP 2017).}, author = {Hahn, Sebastian and Bethge, Joseph and Döllner, Jürgen}, booktitle = {Proceedings of the 8th International Conference of Information Visualization Theory and Applications (IVAPP 2017)}, month = 2, title = {Relative Direction Change: A Topology-based Metric for Layout Stability in Treemaps}, year = 2017 }

2016 [ nach oben ]

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  Dynamic 2.5D Treemaps using Declarative 3D on the Web. Limberger, Daniel; Scheibel, Willy; Lemme, Stefan; Jürgen, Döllner (2016). 33--36.
  [ BibTeX ] [ Details ]
   
  @inproceedings{LSLD2016, abstract = {The 2.5D treemap represents a general purpose visualization technique to map multi-variate hierarchical data in a scalable, interactive, and consistent way used in a number of application fields. In this paper, we explore the capabilities of Declarative 3D for the web-based implementation of 2.5D treemap clients. Particularly, we investigate how X3DOM and XML3D can be used to implement clients with equivalent features that interactively display 2.5D treemaps with dynamic mapping of attributes. We also show a first step towards a glTF-based implementation. These approaches are benchmarked focusing on their interaction capabilities with respect to rendering and speed of dynamic data mapping. We discuss the results for our representative example of a complex 3D interactive visualization technique and summerize recommendations for improvements towards operational web clients.}, author = {Limberger, Daniel and Scheibel, Willy and Lemme, Stefan and Jürgen, Döllner}, booktitle = {Proceedings of the 21st International Conference on Web3D Technology}, pages = {33--36}, title = {Dynamic 2.5D Treemaps using Declarative 3D on the Web}, year = 2016 }
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  Interactive GPU-based Image Deformation for Mobile Devices. Vollmer, Jan Ole; Trapp, Matthias; Döllner, Jürgen (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{VTD2016, abstract = {Interactive image deformation is an important feature of modern image processing pipelines. It is often used to create caricatures and animation for input images, especially photos. State-of-the-art image deformation techniques are based on transforming vertices of a mesh, which is textured by the input image, using affine transformations such as translation, and scaling. However, the resulting visual quality of the output image depends on the geometric resolution of the mesh. Performing these transformations on the CPU often further inhibits performance and quality. This is especially problematic on mobile devices where the limited computational power reduces the maximum achievable quality. To overcome these issue, we propose the concept of an intermediate deformation buffer that stores deformation information at a resolution independent of the mesh resolution. This allows the combination of a high-resolution buffer with a low-resolution mesh for interactive preview, as well as a high-resolution mesh to export the final image. Further, we present a fully GPU-based implementation of this concept, taking advantage of modern OpenGL ES features, such as compute shaders.}, author = {Vollmer, Jan Ole and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Computer Graphics and Visual Computing (CGVC)}, publisher = {The Eurographics Association}, title = {Interactive GPU-based Image Deformation for Mobile Devices}, year = 2016 }
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  Interactive Oil Paint Filtering On Mobile Devices. Semmo, Amir; Trapp, Matthias; Pasewaldt, Sebastian; Döllner, Jürgen (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{STPD2016, abstract = {Image stylization enjoys a growing popularity on mobile devices to foster casual creativity. However, the implementation and provision of high-quality image filters for artistic rendering is still faced by the inherent limitations of mobile graphics hardware such as computing power and memory resources. This work presents a mobile implementation of a filter that transforms images into an oil paint look, thereby highlighting concepts and techniques on how to perform multi-stage nonlinear image filtering on mobile devices. The proposed implementation is based on OpenGL ES and the OpenGL ES shading language, and supports on-screen painting to interactively adjust the appearance in local image regions, e.g., to vary the level of abstraction, brush, and stroke direction. Evaluations of the implementation indicate interactive performance and results that are of similar aesthetic quality than its original desktop variant.}, author = {Semmo, Amir and Trapp, Matthias and Pasewaldt, Sebastian and Döllner, Jürgen}, booktitle = {Expressive 2016 - Posters, Artworks, and Bridging Papers}, title = {Interactive Oil Paint Filtering On Mobile Devices}, year = 2016 }
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  BeCasso: Image Stylization by Interactive Oil Paint Filtering on Mobile Devices. Semmo, Amir; Döllner, Jürgen; Schlegel, Frank (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{SDS2016, abstract = {BeCasso is a mobile app that enables users to transform photos into an oil paint look that is inspired by traditional painting elements. In contrast to stroke-based approaches, the app uses state-of-the-art nonlinear image filtering techniques based on smoothed structure information to interactively synthesize oil paint renderings with soft color transitions. BeCasso empowers users to easily create aesthetic oil paint renderings by implementing a two-fold strategy. First, it provides parameter presets that may serve as a starting point for a custom stylization based on global parameter adjustments. Second, it introduces a novel interaction approach that operates within the parameter spaces of the stylization effect to facilitate creative control over the visual output: on-screen painting enables users to locally adjust the appearance in image regions, e.g., to vary the level of abstraction, brush and stroke direction. This way, the app provides tools for both higher-level interaction and low-level control [Isenberg 2016] to serve the different needs of non-experts and digital artists. References: Isenberg, T. 2016. Interactive NPAR: What Type of Tools Should We Create? In Proc. NPAR, The Eurographics Association, Goslar, Germany, 89–96}, author = {Semmo, Amir and Döllner, Jürgen and Schlegel, Frank}, booktitle = {Proceedings ACM SIGGRAPH Appy Hour}, month = 7, title = {BeCasso: Image Stylization by Interactive Oil Paint Filtering on Mobile Devices}, year = 2016 }
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  Interactive and View-Dependent See-Through Lenses for Massive 3D Point Clouds. Discher, Sören; Richter, Rico; Döllner, Jürgen (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{DRD2016, author = {Discher, Sören and Richter, Rico and Döllner, Jürgen}, booktitle = {Advances in 3D Geoinformation}, title = {Interactive and View-Dependent See-Through Lenses for Massive 3D Point Clouds}, year = 2016 }
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  Konzepte und Techniken zur servicebasierten Visualisierung von geovirtuellen 3D-Umgebungen. Technical Report (PhD dissertation), Hagedorn, Benjamin PhD thesis, Potsdam. (2016).
  [ BibTeX ] [ URL ] [ Details ]
   
  @phdthesis{hagedorn2016konzepte, abstract = {Im Allgemeinen liegen Geodaten und georeferenzierte Daten verteilt vor, sind heterogen in ihrem Inhalt und ihrer Form, umfassen sehr große Datenmengen und müssen in verschiedenen IT-Informationssystemen integriert und in verschiedenen Anwendungskontexten genutzt werden. Im Mittelpunkt dieser Arbeit stehen deshalb Konzepte und Techniken für die Integration, Visualisierung, Analyse, Bereitstellung und Nutzung von 2D- und 3D-Geodaten sowie georeferenzierten Daten. Hierbei wird ein Ansatz verfolgt, der zum einen virtuelle 3D-Umgebungen als konzeptionellen und technischen Rahmen nutzt und zum anderen auf serviceorientierten Softwarearchitekturen und Geo-Standards basiert. Die vorgestellten Konzepte und Verfahren stellen damit Schlüsselbausteine dar, um neuartige IT-Lösungen und Anwendungen für 3D-Geoinformationen, z.B. als Bestandteile von Geodateninfrastrukturen, zu realisieren. Im Bereich der servicebasierten 3DGeovisualisierung beschreibt diese Arbeit, wie virtuelle 3D-Stadtmodelle für die Integration heterogener und verteilter Geodatenquellen genutzt werden können. Dazu werden Anforderungen für die Integration identifiziert und ein Konzept für die Integration auf Datenebene und die Integration auf Visualisierungsebene entworfen und deren Umsetzung am Beispiel komplexer 3D-Bauwerksinformationsmodelle beschrieben und demonstriert. Im Bereich servicebasierter, bildbasierter 3DPortrayal-Services wird mit dem Web View Service (WVS) ein spezialisierter SoftwareService für die Visualisierung, Interaktion und Analyse von geovirtuellen 3D-Umgebungen konzipiert und entwickelt. Kernkonzept dieses Services sind die serverseitige Datenintegration und -verwaltung sowie die ebenfalls serverseitige Bilderzeugung. Mit diesem durchgehend serverseitigen Ansatz können sehr große Mengen an 3D-Geodaten auch auf solchen Endgeräte bereitgestellt werden, die nicht über ausreichend Speicher und Rechenleistung für die Vorhaltung, die Verarbeitung und das Rendering von 3D-Modellen verfügen. Der entwickelte WVS ermöglicht so u.a. auch auf Tablet-PCs und im Webbrowser die interaktive Erkundung und Analyse von 3D-Geodaten. Anhand einer Referenzimplementierung des WVS und einer Client-Anwendung wird die praktische Anwendung des WVS demonstriert. Im Bereich der Komposition von Web View Services wird untersucht, wie der WVS als Baustein einer komplexen, verteilten Visualisierungs- und Renderingpipeline eingesetzt werden kann. Durch die Komposition des WVS mit anderen Darstellungs- und Verarbeitungsservices können z. B. komplexe Renderingeffekte erzielt oder einzelne 3D-Objekte nachträglich in eine 3D-Ansicht integriert werden. Hierzu wird ein Konzept zur servicebasierten, Tiefenbildbasierten Bildkomposition beschrieben und am Beispiel der verdeckungsfreien Annotation von 3D-Ansichten umgesetzt und demonstriert. Im Bereich der Interaktion mit Web View Services liefert diese Arbeit Grundlagen, Konzept und Umsetzung für intelligente, assistierende und automatisierte Interaktions- und Navigationstechniken, die auf dem Angebotscharakter (der Affordanz) von 3D-Szenenobjekten sowie auf der skizzen- und gestenbasierten Eingabe von Nutzerintentionen basiert. Diese Eingaben werden hinsichtlich ihrer Form und unter Berücksichtigung der Semantik der 3DSzenenobjekte ausgewertet und interpretiert und anschließend in anwendungsspezifische Navigationskommandos übersetzt, aus denen teilautomatische Kamerafahrten abgeleitet werden.}, address = {Potsdam}, author = {Hagedorn, Benjamin}, month = {jan}, school = {Universität Potsdam}, title = {Konzepte und Techniken zur servicebasierten Visualisierung von geovirtuellen 3D-Umgebungen}, type = {doctoral}, year = 2016 }
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  Interactive Web-based Visualization for Accessibility Mapping of Transportation Networks. Schoedon, Alexander; Trapp, Matthias; Hollburg, Henning; Döllner, Jürgen (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{STHD2016, abstract = {Accessibility is a fundamental aspect in transportation, routing, and spare-time activity planning concerning traveling in modern cities. In this context, interactive web-based accessibility-map visualization techniques and systems are important tools for provisioning, exploration, analysis, and assessment of multi-modal and location-based travel time data and routing information. To enable their effective application, such interactive visualization techniques demands for flexible mappings with respect to user-adjustable parameters such as maximum travel times, the types of transportation used, or used color schemes. However, traditional approaches for web-based visualization of accessibility-maps do not allow this degree of parametrization without significant latencies introduced by required data processing and transmission between the routing server and the visualization client. This paper presents a novel web-based visualization technique that allows for efficient client-side mapping and rendering of accessibility data onto transportation networks using WebGL and the OpenGL transmission format. A performance evaluation and comparison shows the superior performance of the approach over alternative implementations.}, author = {Schoedon, Alexander and Trapp, Matthias and Hollburg, Henning and Döllner, Jürgen}, booktitle = {Proceedings of EuroVis 2016 - Short Papers}, month = 6, title = {Interactive Web-based Visualization for Accessibility Mapping of Transportation Networks}, year = 2016 }
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  Interactive Revision Exploration using Small Multiples of Software Maps. Scheibel, Willy; Trapp, Matthias; Döllner, Jürgen in IVAPP 2016 (2016). 131-138.
  [ BibTeX ] [ Details ]
   
  @inproceedings{STD2016, abstract = {To explore and to compare different revisions of complex software systems is a challenging task as it requires to constantly switch between different revisions and the corresponding information visualization. This paper proposes to combine the concept of small multiples and focus+context techniques for software maps to facilitate the comparison of multiple software map themes and revisions simultaneously on a single screen. This approach reduces the amount of switches and helps to preserve the mental map of the user. Given a software project the small multiples are based on a common dataset but are specialized by specific revisions and themes. The small multiples are arranged in a matrix where rows and columns represents different themes and revisions, respectively. To ensure scalability of the visualization technique we also discuss two rendering pipelines to ensure interactive frame-rates. The capabilities of the proposed visualization technique are demonstrated in a collaborative exploration setting using a high-resolution, multi-touch display.}, author = {Scheibel, Willy and Trapp, Matthias and Döllner, Jürgen}, booktitle = {7th International Conference on Information Visualization Theory and Applications}, pages = {131-138}, series = {IVAPP 2016}, title = {Interactive Revision Exploration using Small Multiples of Software Maps}, year = 2016 }
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  Interactive Image Filtering with Multiple Levels-of-Control on Mobile Devices. Semmo, Amir; Dürschmid, Tobias; Trapp, Matthias; Klingbeil, Mandy; Döllner, Jürgen; Pasewaldt, Sebastian (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{SDTKDP2016, abstract = {With the continuous development of mobile graphics hardware, interactive high-quality image stylization based on nonlinear filtering is becoming feasible and increasingly used in casual creativity apps. However, these apps often only serve high-level controls to parameterize image filters and generally lack support for low-level (artistic) control, thus automating art creation rather than assisting it. This work presents a GPU-based framework that enables to parameterize image filters at three levels of control: (1) presets followed by (2) global parameter adjustments can be interactively refined by (3) complementary on-screen painting that operates within the filters' parameter spaces for local adjustments. The framework provides a modular XML-based effect scheme to effectively build complex image processing chains-using these interactive filters as building blocks-that can be efficiently processed on mobile devices. Thereby, global and local parameterizations are directed with higher-level algorithmic support to ease the interactive editing process, which is demonstrated by state-of-the-art stylization effects, such as oil paint filtering and watercolor rendering.}, author = {Semmo, Amir and Dürschmid, Tobias and Trapp, Matthias and Klingbeil, Mandy and Döllner, Jürgen and Pasewaldt, Sebastian}, booktitle = {Proceedings ACM SIGGRAPH Asia Symposium on Mobile Graphics and Interactive Applications}, month = 12, title = {Interactive Image Filtering with Multiple Levels-of-Control on Mobile Devices}, year = 2016 }
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  Interactive Multi-scale Oil Paint Filtering on Mobile Devices. Semmo, Amir; Trapp, Matthias; Dürschmid, Tobias; Döllner, Jürgen; Pasewaldt, Sebastian (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{STDDP2016, abstract = {This work presents an interactive mobile implementation of a filter that transforms images into an oil paint look. At this, a multi-scale approach that processes image pyramids is introduced that uses flow-based joint bilateral upsampling to achieve deliberate levels of abstraction at multiple scales and interactive frame rates. The approach facilitates the implementation of interactive tools that adjust the appearance of filtering effects at run-time, which is demonstrated by an on-screen painting interface for per-pixel parameterization that fosters the casual creativity of non-artists.}, author = {Semmo, Amir and Trapp, Matthias and Dürschmid, Tobias and Döllner, Jürgen and Pasewaldt, Sebastian}, booktitle = {Proceedings ACM SIGGRAPH Posters}, title = {Interactive Multi-scale Oil Paint Filtering on Mobile Devices}, year = 2016 }
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  Evaluation of Sketchiness as a Visual Variable for 2.5D Treemaps. Limberger, Daniel; Fiedler, Carolin; Hahn, Sebastian; Trapp, Matthias; Döllner, Jürgen (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{LFHTD, abstract = {Interactive 2.5D treemaps serve as an effective tool for the visualization of attributed hierarchies, enabling exploration of non-spatial, multi-variate, hierarchical data. In this paper the suitability of sketchiness as a visual variable, e.g., for uncertainty, is evaluated. Therefore, a design space for sketchy rendering in 2.5D and integration details for real-time applications are presented. The results of three user studies indicate, that sketchiness is a promising candidate for a visual variable that can be used independently and in addition to others, e.g., color and height. © The Authors 2016. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the 20th International Conference on Information Visualization (IV'16).}, author = {Limberger, Daniel and Fiedler, Carolin and Hahn, Sebastian and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of the 20th International Conference of Information Visualization (IV'16)}, month = 5, title = {Evaluation of Sketchiness as a Visual Variable for 2.5D Treemaps}, year = 2016 }
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  Image Stylization by Interactive Oil Paint Filtering. Semmo, Amir; Limberger, Daniel; Kyprianidis, Jan Eric; Döllner, Jürgen in Computers & Graphics (2016). 55 157--171.
  [ BibTeX ] [ Details ]
   
  @article{SLKD2016, abstract = {This paper presents an interactive system for transforming images into an oil paint look. The system comprises two major stages. First, it derives dominant colors from an input image for feature-aware recolorization and quantization to conform with a global color palette. Afterwards, it employs non-linear filtering based on the smoothed structure adapted to the main feature contours of the quantized image to synthesize a paint texture in real-time. Our filtering approach leads to homogeneous outputs in the color domain and enables creative control over the visual output, such as color adjustments and per-pixel parametrizations by means of interactive painting. To this end, our system introduces a generalized brush-based painting interface that operates within parameter spaces to locally adjust the level of abstraction of the filtering effects. Several results demonstrate the various applications of our filtering approach to different genres of photography.}, author = {Semmo, Amir and Limberger, Daniel and Kyprianidis, Jan Eric and Döllner, Jürgen}, journal = {Computers & Graphics}, pages = {157--171}, title = {Image Stylization by Interactive Oil Paint Filtering}, volume = 55, year = 2016 }
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  Design and Implementation of Non-Photorealistic Rendering Techniques for 3D Geospatial Data. Technical Report (PhD dissertation), Semmo, Amir (2016).
  [ BibTeX ] [ Details ]
   
  @phdthesis{S2016, abstract = {Geospatial data has become a natural part of a growing number of information systems and services in the economy, society, and people's personal lives. In particular, virtual 3D city and landscape models constitute valuable information sources within a wide variety of applications such as urban planning, navigation, tourist information, and disaster management. Today, these models are often visualized in detail to provide realistic imagery. However, a photorealistic rendering does not automatically lead to high image quality, with respect to an effective information transfer, which requires important or prioritized information to be interactively highlighted in a context-dependent manner. Approaches in non-photorealistic renderings particularly consider a user's task and camera perspective when attempting optimal expression, recognition, and communication of important or prioritized information. However, the design and implementation of non-photorealistic rendering techniques for 3D geospatial data pose a number of challenges, especially when inherently complex geometry, appearance, and thematic data must be processed interactively. Hence, a promising technical foundation is established by the programmable and parallel computing architecture of graphics processing units. This thesis proposes non-photorealistic rendering techniques that enable both the computation and selection of the abstraction level of 3D geospatial model contents according to user interaction and dynamically changing thematic information. To achieve this goal, the techniques integrate with hardware-accelerated rendering pipelines using shader technologies of graphics processing units for real-time image synthesis. The techniques employ principles of artistic rendering, cartographic generalization, and 3D semiotics—unlike photorealistic rendering—to synthesize illustrative renditions of geospatial feature type entities such as water surfaces, buildings, and infrastructure networks. In addition, this thesis contributes a generic system that enables to integrate different graphic styles—photorealistic and non-photorealistic—and provide their seamless transition according to user tasks, camera view, and image resolution. Evaluations of the proposed techniques have demonstrated their significance to the field of geospatial information visualization including topics such as spatial perception, cognition, and mapping. In addition, the applications in illustrative and focus+context visualization have reflected their potential impact on optimizing the information transfer regarding factors such as cognitive load, integration of non-realistic information, visualization of uncertainty, and visualization on small displays.}, author = {Semmo, Amir}, month = 11, school = {University of Potsdam}, title = {Design and Implementation of Non-Photorealistic Rendering Techniques for 3D Geospatial Data}, year = 2016 }
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  BeCasso: Artistic Image Processing and Editing on Mobile Devices. Pasewaldt, Sebastian; Semmo, Amir; Döllner, Jürgen; Schlegel, Frank (2016).
  [ BibTeX ] [ Details ]
   
  @inproceedings{PSDS2016, abstract = {BeCasso is a mobile app that enables users to transform photos into high-quality, high-resolution non-photorealistic renditions, such as oil and watercolor paintings, cartoons, and colored pencil drawings, which are inspired by real-world paintings or drawing techniques. In contrast to neuronal network and physically-based approaches, the app employs state-of-the-art nonlinear image filtering. For example, oil paint and cartoon effects are based on smoothed structure information to interactively synthesize renderings with soft color transitions. BeCasso empowers users to easily create aesthetic renderings by implementing a two-fold strategy: First, it provides parameter presets that may serve as a starting point for a custom stylization based on global parameter adjustments. Thereby, users can obtain initial renditions that may be fine-tuned afterwards. Second, it enables local style adjustments: using on-screen painting metaphors, users are able to locally adjust different stylization features, e.g., to vary the level of abstraction, pen, brush and stroke direction or the contour lines. In this way, the app provides tools for both higher-level interaction and low-level control [Isenberg 2016] to serve the different needs of non-experts and digital artists. References: Isenberg, T. 2016. Interactive NPAR: What Type of Tools Should We Create? In Proc. NPAR, The Eurographics Association, Goslar, Germany, 89–96}, author = {Pasewaldt, Sebastian and Semmo, Amir and Döllner, Jürgen and Schlegel, Frank}, booktitle = {Proceedings ACM SIGGRAPH Asia Symposium on Mobile Graphics and Interactive Applications (Demo)}, month = 12, title = {BeCasso: Artistic Image Processing and Editing on Mobile Devices}, year = 2016 }

2015 [ nach oben ]

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  Automatic Detection and Large-Scale Visualization of Trees for Digital Landscapes and City Models based on 3D Point Clouds. Oehlke, Christoph; Richter, Rico; Döllner, Jürgen (2015). 151-160.
  [ BibTeX ] [ Details ]
   
  @inproceedings{ORD2015, author = {Oehlke, Christoph and Richter, Rico and Döllner, Jürgen}, booktitle = {16th Conference on Digital Landscape Architecture (DLA 2015)}, pages = {151-160}, title = {Automatic Detection and Large-Scale Visualization of Trees for Digital Landscapes and City Models based on 3D Point Clouds}, year = 2015 }
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  Animated visualization of spatial-temporal trajectory data for air-traffic analysis. Buschmann, Stefan; Trapp, Matthias; Döllner, Jürgen in The Visual Computer (2015). 32(3) 371-381.
  [ BibTeX ] [ Details ]
   
  @article{BTD2015A, abstract = {With increasing numbers of flights worldwide and a continuing rise in airport traffic, air-traffic management is faced with a number of challenges. These include monitoring, reporting, planning, and problem analysis of past and current air traffic, e.g., to identify hotspots, minimize delays, or to optimize sector assignments to air-traffic controllers. To cope with these challenges, cyber worlds can be used for interactive visual analysis and analytical reasoning based on aircraft trajectory data. However, with growing data size and complexity, visualization requires high computational efficiency to process that data within real-time constraints. This paper presents a technique for real-time animated visualization of massive trajectory data. It enables (1) interactive spatio-temporal filtering, (2) generic mapping of trajectory attributes to geometric representations and appearance, and (3) real-time rendering within 3D virtual environments such as virtual 3D airport or 3D city models. Different visualization metaphors can be efficiently built upon this technique such as temporal focus+context, density maps, or overview+detail methods. As a general-purpose visualization technique, it can be applied to general 3D and 3+1D trajectory data, e.g., traffic movement data, geo-referenced networks, or spatio-temporal data, and it supports related visual analytics and data mining tasks within cyber worlds.}, author = {Buschmann, Stefan and Trapp, Matthias and Döllner, Jürgen}, journal = {The Visual Computer}, number = 3, pages = {371-381}, title = {Animated visualization of spatial-temporal trajectory data for air-traffic analysis}, volume = 32, year = 2015 }
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  Echtzeit-Rendering-Techniken für 3D-Punktwolken basierend auf semantischen und topologischen Attributen. Discher,; Sören, (2015).
  [ BibTeX ] [ Details ]
   
  @inproceedings{DRD2015, author = {Discher and Sören}, booktitle = {Shortlist Karl Kraus Young Scientists Award 2015, 35. Wissenschaftlich-Technische Jahrestagung der DGPF}, title = {Echtzeit-Rendering-Techniken für 3D-Punktwolken basierend auf semantischen und topologischen Attributen}, year = 2015 }
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  Geometry Batching Using Texture-Arrays. Trapp, Matthias; Döllner, Jürgen (2015). 239-246.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TD2015, abstract = {High-quality rendering of 3D virtual environments typically depends on high-quality 3D models with significant geometric complexity and texture data. One major bottleneck for real-time image-synthesis represents the number of state changes, which a specific rendering API has to perform. To improve performance, batching can be used to group and sort geometric primitives into batches to reduce the number of required state changes, whereas the size of the batches determines the number of required draw-calls, and therefore, is critical for rendering performance. For example, in the case of texture atlases, which provide an approach for efficient texture management, the batch size is limited by the efficiency of the texture-packing algorithm and the texture resolution itself. This paper presents a pre-processing approach and rendering technique that overcomes these limitations by further grouping textures or texture atlases and thus enables the creation of larger geometry batches. It is based on texture arrays in combination with an additional indexing schema that is evaluated at run-time using shader programs. This type of texture management is especially suitable for real-time rendering of large-scale texture-rich 3D virtual environments, such as virtual city and landscape models.}, author = {Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of the 10th International Conference on Computer Graphics Theory and Applications (GRAPP 2015)}, pages = {239-246}, title = {Geometry Batching Using Texture-Arrays}, year = 2015 }
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  Natural Phenomena as Metaphors for Visualization of Trend Data in Interactive Software Maps. Würfel, Hannes; Trapp, Matthias; Limberger, Daniel; Döllner, Jürgen (2015).
  [ BibTeX ] [ Details ]
   
  @inproceedings{WTLD2015, abstract = {Software maps are a commonly used tool for code quality monitoring in software-development projects and decision making processes. While providing an important visualization technique for the hierarchical system structure of a single software revision, they lack capabilities with respect to the visualization of changes over multiple revisions. This paper presents a novel technique for visualizing the evolution of the software system structure based on software metric trends. These trend maps extend software maps by using real-time rendering techniques for natural phenomena yielding additional visual variables that can be effectively used for the communication of changes. Therefore, trend data is automatically computed by hierarchically aggregating software metrics. We demonstrate and discuss the presented technique using two real world data sets of complex software systems.}, author = {Würfel, Hannes and Trapp, Matthias and Limberger, Daniel and Döllner, Jürgen}, booktitle = {Computer Graphics and Visual Computing (CGVC)}, organization = {The Eurographics Association}, title = {Natural Phenomena as Metaphors for Visualization of Trend Data in Interactive Software Maps}, year = 2015 }
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  ThreadCity: Combined Visualization of Structure and Activity for the Exploration of Multi-threaded Software Systems. Hahn, Sebastian; Trapp, Matthias; Wuttke, Nikolai; Döllner, Jürgen (2015).
  [ BibTeX ] [ Details ]
   
  @inproceedings{HTWD15, abstract = {This paper presents a novel visualization technique for the interactive exploration of multi-threaded software systems. It combines the visualization of static system structure based on the EvoStreets approach with an additional traffic metaphor to communicate the runtime characteristics of multiple threads simultaneously. To improve visual scalability with respect to the visualization of complex software systems, we further present an effective level-of-detail visualization based on hierarchical aggregation of system components by taking viewing parameters into account. We demonstrate our technique by means of a prototypical implementation and compare our result with existing visualization techniques. © The Authors 2015. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the 19th International Conference on Information Visualization (IV'15).}, author = {Hahn, Sebastian and Trapp, Matthias and Wuttke, Nikolai and Döllner, Jürgen}, booktitle = {Proceedings of the 19th International Conference of Information Visualization (IV'15)}, month = 7, title = {ThreadCity: Combined Visualization of Structure and Activity for the Exploration of Multi-threaded Software Systems}, year = 2015 }
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  Interactive Image Filtering for Level-of-Abstraction Texturing of Virtual 3D Scenes. Semmo, Amir; Döllner, Jürgen in Computers & Graphics (2015). 52 181--198.
  [ BibTeX ] [ Details ]
   
  @article{SD2015, abstract = {Texture mapping is a key technology in computer graphics. For the visual design of 3D scenes, in particular, effective texturing depends significantly on how important contents are expressed, e.g., by preserving global salient structures, and how their depiction is cognitively processed by the user in an application context. Edge-preserving image filtering is one key approach to address these concerns. Much research has focused on applying image filters in a post-process stage to generate artistically stylized depictions. However, these approaches generally do not preserve depth cues, which are important for the perception of 3D visualization (e.g., texture gradient). To this end, filtering is required that processes texture data coherently with respect to linear perspective and spatial relationships. In this work, we present an approach for texturing 3D scenes with perspective coherence by arbitrary image filters. We propose decoupled deferred texturing with (1) caching strategies to interactively perform image filtering prior to texture mapping and (2) for each mipmap level separately to enable a progressive level of abstraction, using (3) direct interaction interfaces to parameterize the visualization according to spatial, semantic, and thematic data. We demonstrate the potentials of our method by several applications using touch or natural language inputs to serve the different interests of users in specific information, including illustrative visualization, focus+context visualization, geometric detail removal, and semantic depth of field. The approach supports frame-to-frame coherence, order-independent transparency, multitexturing, and content-based filtering. In addition, it seamlessly integrates into real-time rendering pipelines, and is extensible for custom interaction techniques.}, author = {Semmo, Amir and Döllner, Jürgen}, journal = {Computers & Graphics}, pages = {181--198}, title = {Interactive Image Filtering for Level-of-Abstraction Texturing of Virtual 3D Scenes}, volume = 52, year = 2015 }
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  Out-of-Core Visualization of Classified 3D Point Clouds. Richter, Rico; Discher, Sören; Döllner, Jürgen (2015). 227-242.
  [ BibTeX ] [ Details ]
   
  @inproceedings{RDD2014, abstract = {3D point clouds represent an essential category of geodata used in a variety of geoinformation applications and systems. We present a novel, interactive out-of-core rendering technique for massive 3D point clouds based on a layered, multi-resolution kd-tree, whereby point-based rendering techniques are selected according to each point's classification (e.g., vegetation, buildings, terrain). The classification-dependent rendering leads to an improved visual representation, enhances recognition of objects within 3D point cloud depictions, and facilitates visual filtering and highlighting. To interactively explore objects, structures, and relations represented by 3D point clouds, our technique provides efficient means for an instantaneous, ad-hoc visualization compared to approaches that visualize 3D point clouds by deriving mesh-based 3D models. We have evaluated our approach for massive laser scan datasets of urban areas. The results show the scalability of the technique and how different configurations allow for designing task and domain-specific analysis and inspection tools. © The Authors 2014. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in 3D Geoinformation Science: The Selected Papers of the 3D GeoInfo 2014 by Springer International Publishing. http://dx.doi.org/10.1007/978-3-319-12181-9.}, author = {Richter, Rico and Discher, Sören and Döllner, Jürgen}, booktitle = {3D Geoinformation Science: The Selected Papers of the 3D GeoInfo 2014}, pages = {227-242}, publisher = {Cham: Springer International Publishing}, title = {Out-of-Core Visualization of Classified 3D Point Clouds}, year = 2015 }
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  Image Stylization by Oil Paint Filtering using Color Palettes. Semmo, Amir; Limberger, Daniel; Kyprianidis, Jan Eric; Döllner, Jürgen (2015). 149--158.
  [ BibTeX ] [ Details ]
   
  @inproceedings{SLKD15, abstract = {This paper presents an approach for transforming images into an oil paint look. To this end, a color quantization scheme is proposed that performs feature-aware recolorization using the dominant colors of the input image. In addition, an approach for real-time computation of paint textures is presented that builds on the smoothed structure adapted to the main feature contours of the quantized image. Our stylization technique leads to homogeneous outputs in the color domain and enables creative control over the visual output, such as color adjustments and per-pixel parametrizations by means of interactive painting. © The Authors 2015. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe'15).}, author = {Semmo, Amir and Limberger, Daniel and Kyprianidis, Jan Eric and Döllner, Jürgen}, booktitle = {Proceedings International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe)}, month = 6, pages = {149--158}, title = {Image Stylization by Oil Paint Filtering using Color Palettes}, year = 2015 }
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  Review: visual analytics of climate networks. Nocke, Thomas; Buschmann, Stefan; Donges, Jonathan; Marwan, Norbert; Schulz, Hans-Jörg; Tominski, Christian in Nonlinear Processes in Geophysics (2015). 22(5) 545-570.
  [ BibTeX ] [ Details ]
   
  @article{NBDMST2015, abstract = {Network analysis has become an important approach in studying complex spatiotemporal behaviour within geophysical observation and simulation data. This new field produces increasing amounts of large geo-referenced networks to be analysed. Particular focus lies currently on the network analysis of the complex statistical interrelationship structure within climatological fields. The standard procedure for such network analyses is the extraction of network measures in combination with static standard visualisation methods. Existing interactive visualisation methods and tools for geo-referenced network exploration are often either not known to the analyst or their potential is not fully exploited. To fill this gap, we illustrate how interactive visual analytics methods in combination with geovisualisation can be tailored for visual climate network investigation. Therefore, the paper provides a problem analysis, relating the multiple visualisation challenges with a survey undertaken with network analysts from the research fields of climate and complex systems science. Then, as an overview for the interested practitioner, we review the state-of-the-art in climate network visualisation and provide an overview of existing tools. As a further contribution, we introduce the visual network analytics tools CGV and GTX, providing tailored solutions for climate network analysis, including alternative geographic projections, edge bundling, and 3-D network support. Using these tools, the paper illustrates the application potentials of visual analytics for climate networks based on several use cases including examples from global, regional, and multi-layered climate networks.}, author = {Nocke, Thomas and Buschmann, Stefan and Donges, Jonathan and Marwan, Norbert and Schulz, Hans-Jörg and Tominski, Christian}, journal = {Nonlinear Processes in Geophysics}, month = 9, number = 5, pages = {545-570}, title = {Review: visual analytics of climate networks}, volume = 22, year = 2015 }
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  VideoMR: A Map and Reduce Framework for Real-time Video Processing. Meier, Benjamin-Heinz; Trapp, Matthias; Döllner, Jürgen (2015).
  [ BibTeX ] [ Details ]
   
  @inproceedings{MTD2015, abstract = {This paper presents VideoMR: a novel map and reduce framework for real-time video processing on graphic processing units (GPUs). Using the advantages of implicit parallelism and bounded memory allocation, our approach enables developers to focus on implementing video operations without taking care of GPU memory handling or the details of code parallelization. Therefore, a new concept for map and reduce is introduced, redefining both operations to fit to the specific requirements of video processing. A prototypical implementation using OpenGL facilitates various operating platforms, including mobile development, and will be widely interoperable with other state-of-the-art video processing frameworks.}, author = {Meier, Benjamin-Heinz and Trapp, Matthias and Döllner, Jürgen}, booktitle = {International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision (WSCG 2015)}, title = {VideoMR: A Map and Reduce Framework for Real-time Video Processing}, year = 2015 }
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  Real-Time Visualization of Massive Movement Data in Digital Landscapes. Buschmann, Stefan; Trapp, Matthias; Döllner, Jürgen (2015). 213-220.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BTD2015, abstract = {Due to continuing advances in sensor technology and increasing availability of digital infrastructure that allows for acquisition, transfer, and storage of big data sets, large amounts of movement data (e.g., road, naval, or air-traffic) become available. In the near future, movement data such as traffic data may even be available in real-time. In a growing number of application fields (e.g., landscape planning and design, urban development, and infrastructure planning), movement data enables new analysis and simulation applications. In this paper, we present an interactive technique for visualizing massive 3D movement trajectories. It is based on mapping massive movement data to graphics primitives and their visual variables in real-time, supporting a number of visualization schemes such as sphere, line, or tube-based trajectories, including animations of direction and speed. This generic technique enhances the functionality of VR and interactive 3D systems using virtual environments such as digital landscape models, city models, or virtual globes by adding support for this important category of spatio-temporal data.}, author = {Buschmann, Stefan and Trapp, Matthias and Döllner, Jürgen}, booktitle = {16th Conference on Digital Landscape Architecture (DLA 2015)}, pages = {213-220}, title = {Real-Time Visualization of Massive Movement Data in Digital Landscapes}, year = 2015 }
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  Interactive Rendering and Stylization of Transportation Networks Using Distance Fields. Trapp, Matthias; Semmo, Amir; Döllner, Jürgen (2015). 207-219.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TSD2015, abstract = {Transportation networks, such as streets, railroads or metro systems, constitute primary elements in cartography for reckoning and navigation. In recent years, they have become an increasingly important part of 3D virtual environments for the interactive analysis and communication of complex hierarchical information, for example in routing, logistics optimization, and disaster management. A variety of rendering techniques have been proposed that deal with integrating transportation networks within these environments, but have so far neglected the many challenges of an interactive design process to adapt their spatial and thematic granularity (i.e., level-of-detail and level-of-abstraction) according to a user's context. This paper presents an efficient real-time rendering technique for the view-dependent rendering of geometrically complex transportation networks within 3D virtual environments. Our technique is based on distance fields using deferred texturing that shifts the design process to the shading stage for real-time stylization. We demonstrate and discuss our approach by means of street networks using cartographic design principles for context-aware stylization, including view-dependent scaling for clutter reduction, contour-lining to provide figure-ground, handling of street crossings via shading-based blending, and task-dependent colorization. Finally, we present potential usage scenarios and applications together with a performance evaluation of our implementation.}, author = {Trapp, Matthias and Semmo, Amir and Döllner, Jürgen}, booktitle = {Proceedings of the 10th International Conference on Computer Graphics Theory and Applications (GRAPP 2015)}, pages = {207-219}, title = {Interactive Rendering and Stylization of Transportation Networks Using Distance Fields}, year = 2015 }
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  Cartography-Oriented Design of 3D Geospatial Information Visualization - Overview and Techniques. Semmo, Amir; Trapp, Matthias; Jobst, Markus; Döllner, Jürgen in The Cartographic Journal (2015). 52(2) 95--106.
  [ BibTeX ] [ Details ]
   
  @article{SD2015, abstract = {In economy, society and personal life map-based, interactive geospatial visualization becomes a natural element of a growing number of applications and systems. The visualization of 3D geospatial information, however, raises the question how to represent the information in an effective way. Considerable research has been done in technology-driven directions in the fields of cartography and computer graphics (e.g., design principles, visualization techniques). Here, non-photorealistic rendering represents a promising visualization category–situated between both fields–that offers a large number of degrees for the cartography-oriented visual design of complex 2D and 3D geospatial information for a given application context. Still today, however, specifications and techniques for mapping cartographic design principles to the state-of-the-art rendering pipeline of 3D computer graphics remain to be explored. This paper revisits cartographic design principles for 3D geospatial visualization and introduces an extended 3D semiotic model that complies with the general, interactive visualization pipeline. Based on this model, we propose non-photorealistic rendering techniques to interactively synthesize cartographic renditions of basic feature types, such as terrain, water, and buildings. In particular, it includes a novel iconification concept to seamlessly interpolate between photorealistic and cartographic representations of 3D landmarks. Our work concludes with a discussion of open challenges in this field of research, including topics such as user interaction and evaluation.}, author = {Semmo, Amir and Trapp, Matthias and Jobst, Markus and Döllner, Jürgen}, journal = {The Cartographic Journal}, number = 2, pages = {95--106}, title = {Cartography-Oriented Design of 3D Geospatial Information Visualization - Overview and Techniques}, volume = 52, year = 2015 }

2014 [ nach oben ]

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  Service-Based 3D Rendering and Interactive 3D Visualization (2012). Hagedorn, Benjamin; Döllner, Jürgen in HPI Future SOC Lab: Proceedings 2012, C. Meinel, Polze, A., Oswald, G., Strotmann, R., Seibold, U., Bernhard, S. (reds.) (2014). 7-10.
  [ BibTeX ] [ URL ] [ Details ]
   
  @incollection{hagedorn2014servicebased, abstract = {This report describes the subject and preliminary results of our work in the context of the HPI Future SOC Lab, which generally aims on how to exploit high performance computing (HPC) capabilities for service-based 3D rendering and service‐based, interactive 3D visualization. A major focus is on the application of HPC technologies for the creation, management, analysis, and visualization of and interaction with virtual 3D environments, especially with complex 3D city models.}, author = {Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {HPI Future SOC Lab: Proceedings 2012}, editor = {Meinel, Christoph and Polze, Andreas and Oswald, Gerhard and Strotmann, Rolf and Seibold, Ulrich and Bernhard, Schulzki}, pages = {7-10}, publisher = {Universitätsverlag Potsdam}, series = {Technische Berichte des Hasso-Plattner-Instituts für Softwaresystemtechnik an der Universität Potsdam}, title = {Service-Based 3D Rendering and Interactive 3D Visualization (2012)}, type = {technical report}, year = 2014 }
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  Multi-Perspective 3D Panoramas. Pasewaldt, Sebastian; Semmo, Amir; Trapp, Matthias; Döllner, Jürgen in International Journal of Geographical Information Science (IJGIS) (2014). 28(10) 2030-2051.
  [ BibTeX ] [ Details ]
   
  @article{PSTD2014, abstract = {This article presents multi-perspective 3D panoramas that focus on visualizing 3D geovirtual environments (3D GeoVEs) for navigation and exploration tasks. Their key element, a multi-perspective view, seamlessly combines what is seen from multiple viewpoints into a single image. This approach facilitates thepresentation of information for virtual 3D city and landscape models, particularly by reducing occlusions, increasing screen-space utilization, and providing additional context within a single image. We complement multi-perspective views with cartographic visualization techniques to stylize features according to their semantics and highlight important or prioritized information. When combined, both techniques constitute the core implementation of interactive, multi-perspective 3D panoramas. They offer a large number of effective means for visual communication of 3D spatial information, a high degree of customization with respect to cartographic design, and manifold applications in different domains. We discuss design decisions of 3D panoramas for the exploration of and navigation in 3D GeoVEs. We also discuss a preliminary user study that indicates that 3D panoramas are a promising approach for navigation systems using 3D GeoVEs.}, author = {Pasewaldt, Sebastian and Semmo, Amir and Trapp, Matthias and Döllner, Jürgen}, journal = {International Journal of Geographical Information Science (IJGIS)}, number = 10, pages = {2030-2051}, title = {Multi-Perspective 3D Panoramas}, volume = 28, year = 2014 }
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  Oil Paint Filtering Using Color Palettes For Colorization. Semmo, Amir; Döllner, Jürgen (2014).
  [ BibTeX ] [ Details ]
   
  @inproceedings{SD2014_2, abstract = {We present a novel technique for oil paint filtering that uses color palettes for colorization. First, dominant feature-aware colors are derived from the input image via entropy-based metrics. Seed pixels are then determined and propagated to the remaining pixels by adopting the optimization framework of Levin et al. [2004] for feature-aware colorization. Finally, the quantized output is combined with flow-based highlights and contour lines to simulate paint texture. Our technique leads to homogeneous outputs in the color domain and enables interactive control over color definitions.}, author = {Semmo, Amir and Döllner, Jürgen}, booktitle = {Expressive Poster Session}, title = {Oil Paint Filtering Using Color Palettes For Colorization}, year = 2014 }
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  Real-Time Animated Visualization of Massive Air-Traffic Trajectories. Buschmann, Stefan; Trapp, Matthias; Döllner, Jürgen (2014). 172-181.
  [ BibTeX ] [ Details ]
   
  @conference{BTD2014, abstract = {With increasing numbers of flights world-wide and a continuing rise in airport traffic, air-traffic management is faced with a number of challenges. These include monitoring, reporting, planning, and problem analysis of past and current air traffic, e.g., to identify hotspots, minimize delays, or to optimize sector assignments to air-traffic controllers. Interactive and dynamic 3D visualization and visual analysis of massive aircraft trajectories, i.e., analytical reasoning enabled by interactive cyber worlds, can be used to approach these challenges. To facilitate this kind of analysis, especially in the context of real-time data, interactive tools for filtering, mapping, and rendering are required. In particular, the mapping process should be configurable at run-time and support both static mappings and animations to allow users to effectively explore and realize movement dynamics. However, with growing data size and complexity, these stages of the visualization pipeline require computational efficient implementations to be capable of processing within real-time constraints. This paper presents an approach for real-time animated visualization of massive air-traffic data, that implements all stages of the visualization pipeline based on GPU techniques for efficient processing. It enables (1) interactive spatio-temporal filtering, (2) generic mapping of trajectory attributes to geometric representations and appearances, as well as (3) real-time rendering within 3D virtual environments, such as virtual 3D airport and city models. Based on this pipeline, different visualization metaphors (e.g., temporal focus+context, density maps, and overview+detail visualization) are implemented and discussed. The presented concepts and implementation can be generally used as visual analytics and data mining techniques in cyber worlds, e.g., to visualize movement data, geo-referenced networks, or other spatio-temporal data.}, author = {Buschmann, Stefan and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of CyberWorlds 2014}, pages = {172-181}, publisher = {IEEE Computer Society}, title = {Real-Time Animated Visualization of Massive Air-Traffic Trajectories}, year = 2014 }
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  Nichtfotorealistische Visualisierung virtueller 3D-Stadtmodelle. Semmo, Amir in HPImgzn (2014). (15) 32-35.
  [ BibTeX ] [ Details ]
   
  @article{S2014, abstract = {Die nichtfotorealistische Bildsynthese stellt ein umfangreiches, innovatives Repertoire zur grafischen Gestaltung bereit, die eine wirkungsvolle Visualisierung komplexer raumbezogener Informationen ermöglicht. Der Fachbereich für computergrafische Systeme beschäftigt sich u.a. mit dem Design, der Implementierung und Evaluierung von nichtfotorealistischen Visualisierungstechniken für virtuelle 3D-Umgebungen – ein Forschungsbericht von Amir Semmo.}, author = {Semmo, Amir}, journal = {HPImgzn}, number = 15, pages = {32-35}, title = {Nichtfotorealistische Visualisierung virtueller 3D-Stadtmodelle}, year = 2014 }
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  Service-Based 3D Rendering and Interactive 3D Visualization. Hagedorn, Benjamin; Döllner, Jürgen in HPI Future SOC Lab: Proceedings 2013, C. Meinel, Polze, A., Oswald, G., Strotmann, R., Seibold, U., Schulzki, B. (reds.) (2014). 3-5.
  [ BibTeX ] [ URL ] [ Details ]
   
  @incollection{20132013servicebased, author = {Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {HPI Future SOC Lab: Proceedings 2013}, editor = {Meinel, Christoph and Polze, Andreas and Oswald, Gerhard and Strotmann, Rolf and Seibold, Ulrich and Schulzki, Bernhard}, pages = {3-5}, publisher = {Universitätsverlag Potsdam}, series = {Technische Berichte des Hasso-Plattner-Instituts für Softwaresystemtechnik an der Universität Potsdam}, title = {Service-Based 3D Rendering and Interactive 3D Visualization}, type = {technical report}, year = 2014 }
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  Web-based and Mobile Provisioning of Virtual 3D Reconstructions. Klimke, Jan; Hagedorn, Benjamin; Trapp, Matthias; Döllner, Jürgen R. Franken-Wendelstorf, Lindinger, E., Sieck, J. (reds.) (2014). 17--28.
  [ BibTeX ] [ Details ]
   
  @inproceedings{KHTD2014, abstract = {Communication of cultural heritage by means of digital information systems has been gaining more and more importance over recent years. Interactive virtual 3D applications enable users to explore 3D virtual reconstructions in real-time, to directly interact with the contained digital cultural heritage artifacts, and to obtain insights into this data. Nevertheless, these artifacts are usually very detailed and complex 3D models that are hard to handle for end-user systems. This paper presents the concept and a prototypical implementation of an image-based, web-based approach for the communication of digital cultural heritage and its provisioning for the Web and mobile devices by the example of the project Colonia3D – a high-detail, virtual reconstruction and high-detail 3D city model of Roman Cologne. Through this web-based and mobile provisioning, complex digital reconstructions can be used, e.g., on-site to match local findings and reconstructions.}, author = {Klimke, Jan and Hagedorn, Benjamin and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Tagungsband der 12. Konferenz Kultur und Informatik: Reality and Virtuality}, chapter = 2, editor = {Franken-Wendelstorf, R. and Lindinger, E. and Sieck, J.}, month = 5, pages = {17--28}, publisher = {Werner Hülsbusch Verlag}, title = {Web-based and Mobile Provisioning of Virtual 3D Reconstructions}, year = 2014 }
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  Scalable Multi-Platform Distribution of Spatial 3D Contents. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in International Journal of 3-D Information Modeling (2014). 3(3) 35--49.
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{Klimke2014a, abstract = {Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing ren-derings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. This paper introduces a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: (a) The complexity of the 3D city model data is decoupled from data transfer complexity (b) the implementation of client applica-tions is simplified significantly as 3D rendering is encapsulated on server side (c) 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, journal = {International Journal of 3-D Information Modeling}, month = {jan}, number = 3, pages = {35--49}, title = {Scalable Multi-Platform Distribution of Spatial 3D Contents}, volume = 3, year = 2014 }
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  An Interaction Framework for Level-of-Abstraction Visualization of 3D Geovirtual Environments. Semmo, Amir; Döllner, Jürgen (2014). 43--49.
  [ BibTeX ] [ Details ]
   
  @inproceedings{SD2014_3, abstract = {3D geovirtual environments constitute effective media for the analysis and communication of complex geospatial data. Today, these environments are often visualized using static graphical variants (e.g., 2D maps, 3D photorealistic) from which a user is able to choose from. To serve the different interests of users in specific information, however, the spatial and thematic granularity at which model contents are represented (i.e., level of abstraction) should be dynamically adapted to the user's context, which requires specialized interaction techniques for parameterization. In this work, we present a framework that enables interaction interfaces to parameterize the level-of-abstraction visualization according to spatial, semantic, and thematic data. The framework is implemented in a visualization system that provides image-based rendering techniques for context-aware abstraction and highlighting. Using touch and natural language interfaces, we demonstrate its versatile application to geospatial tasks, including exploration, navigation, and orientation.}, author = {Semmo, Amir and Döllner, Jürgen}, booktitle = {Proceedings 2nd ACM SIGSPATIAL Workshop on MapInteraction}, month = 11, pages = {43--49}, title = {An Interaction Framework for Level-of-Abstraction Visualization of 3D Geovirtual Environments}, year = 2014 }
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  Web-based and Mobile Provisioning of Virtual 3D Reconstructions. Klimke, J.; Hagedorn, B.; Trapp, M.; Döllner, J. (2014). 17--28.
  [ BibTeX ] [ Details ]
   
  @inproceedings{KHTD2014, author = {Klimke, J. and Hagedorn, B. and Trapp, M. and Döllner, J.}, booktitle = {Kultur und Informatik: Reality and Virtuality}, number = 5, pages = {17--28}, publisher = {Werner Hülsbusch Verlag}, title = {Web-based and Mobile Provisioning of Virtual 3D Reconstructions}, year = 2014 }
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  Visualization of Varying Hierarchies by Stable Layout of Voronoi Treemaps. Hahn, Sebastian; Trümper, Jonas; Moritz, Dominik; Döllner, Jürgen (2014). 50-58.
  [ BibTeX ] [ Details ]
   
  @inproceedings{STMD2014, abstract = {Space-restricted techniques for visualizing hierarchies generally achieve high scalability and readability (e.g., tree maps, bundle views, sunburst). However, the visualization layout directly depends on the hierarchy, that is, small changes to the hierarchy can cause wide-ranging changes to the layout. For this reason, it is difficult to use these techniques to compare similar variants of a hierarchy because users are confronted with layouts that do not expose the expected similarity. Voronoi treemaps appear to be promising candidates to overcome this limitation. However, existing Voronoi treemap algorithms do not provide deterministic layouts or assume a fixed hierarchy. In this paper we present an extended layout algorithm for Voronoi treemaps that provides a high degree of layout similiarity for varying hierarchies, such as software-system hierarchies. The implementation uses a deterministic initial-distribution approach that reduces the variation in node positioning even if changes in the underlying hierarchy data occur. Compared to existing layout algorithms, our algorithm achieves lower error rates with respect to node areas in the case of weighted Voronoi diagrams, which we show in a comparative study.}, author = {Hahn, Sebastian and Trümper, Jonas and Moritz, Dominik and Döllner, Jürgen}, booktitle = {Proceedings of the 5th International Conference on Information Visualization Theory and Applications (IVAPP 2014)}, month = 1, pages = {50-58}, publisher = {SCITEPRESS – Science and Technology Publications}, title = {Visualization of Varying Hierarchies by Stable Layout of Voronoi Treemaps}, year = 2014 }
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  Hardware-Accelerated Attribute Mapping for Interactive Visualization of Complex 3D Trajectories. Buschmann, Stefan; Trapp, Matthias; Lühne, Patrick; Döllner, Jürgen (2014). 355-363.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BTLD2014, abstract = {The visualization of 3D trajectories of moving objects and related attributes in 3D virtual environments represents a fundamental functionality in various visualization domains. Interactive rendering and visual analytics of such attributed trajectories involves both conceptual questions as well as technical challenges. Specifically, the mapping of trajectory attributes to rendering primitives and appearance represents a challenging task in the case of large data sets of high geometric complexity. There are various visualization approaches and rendering techniques considering specific aspects of these mappings to facilitate visualization and analysis of this kind of data. To solve the underlying general mapping problem efficiently, we developed an approach that uses and combines diverse types of visualizations, rather than being tailored to a specific use case. This paper describes an interactive rendering system for the visualization of 3D trajectories that enables the combinations of different mappings as well as their dynamic configuration at runtime. A fully hardware-accelerated implementation enables the processing of large sets of attributed 3D trajectories in real-time.}, author = {Buschmann, Stefan and Trapp, Matthias and Lühne, Patrick and Döllner, Jürgen}, booktitle = {Proceedings of the 5th International Conference on Information Visualization Theory and Applications (IVAPP 2014)}, month = 1, pages = {355-363}, publisher = {SCITEPRESS – Science and Technology Publications}, title = {Hardware-Accelerated Attribute Mapping for Interactive Visualization of Complex 3D Trajectories}, year = 2014 }
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  Web-based and Mobile Provisioning of Virtual 3D Reconstructions. Klimke, J.; Hagedorn, B.; Trapp, M.; Döllner, J. (2014). 17--28.
  [ BibTeX ] [ Details ]
   
  @inproceedings{KHTD2014, author = {Klimke, J. and Hagedorn, B. and Trapp, M. and Döllner, J.}, booktitle = {Kultur und Informatik: Reality and Virtuality}, number = 5, pages = {17--28}, publisher = {Werner Hülsbusch Verlag}, title = {Web-based and Mobile Provisioning of Virtual 3D Reconstructions}, year = 2014 }
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  Scalable Multi-Platform Distribution of Spatial 3D Contents. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in International Journal of 3-D Information Modeling (2014). 3(3) 35--49.
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{Klimke2014a, abstract = {Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing ren-derings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. This paper introduces a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: (a) The complexity of the 3D city model data is decoupled from data transfer complexity (b) the implementation of client applica-tions is simplified significantly as 3D rendering is encapsulated on server side (c) 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, journal = {International Journal of 3-D Information Modeling}, month = {jan}, number = 3, pages = {35--49}, title = {Scalable Multi-Platform Distribution of Spatial 3D Contents}, volume = 3, year = 2014 }
• 
  Painting Per-Pixel Parametrization for Interactive Image Filtering. Limberger, Daniel; Döllner, Jürgen (2014).
  [ BibTeX ] [ Details ]
   
  @inproceedings{LD2014, abstract = {We present a photo-editing method that enables per-pixel parameter manipulation of image filtering by means of interactive painting. Predefined as well as custom image filters are exposed to the user, as a parametrizable composition of image operations. Brushes, as a sequences of actions mapping user inputs (in terms of brush shape, flow, pressure, etc.) to arbitrary functions or convolution operators, are used to draw within the parameter space. Our tool demonstrates that interactive painting can be used to, e.g., locally tweak inadequate parametrization and, furthermore, provides a blueprint for an open, collaborative photo-editing platform.}, author = {Limberger, Daniel and Döllner, Jürgen}, booktitle = {Expressive Poster Session}, title = {Painting Per-Pixel Parametrization for Interactive Image Filtering}, year = 2014 }
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  Image Filtering for Interactive Level-of-Abstraction Visualization of 3D Scenes. Semmo, Amir; Döllner, Jürgen (2014). 5--14.
  [ BibTeX ] [ Details ]
   
  @inproceedings{SD14, abstract = {Texture mapping is a key technology in computer graphics for visual design of rendered 3D scenes. An effective information transfer of surface properties, encoded by textures, however, depends significantly on how important information is highlighted and cognitively processed by the user in an application context. Edge-preserving image filtering is a promising approach to address this concern while preserving global salient structures. Much research has focused on applying image filters in a post-process stage to foster an artistically stylized rendering, but these approaches are generally not able to preserve depth cues important for 3D visualization (e.g., texture gradient). To this end, filtering that processes texture data coherently with respect to linear perspective and spatial relationships is required. In this work, we present a system that enables to process textured 3D scenes with perspective coherence by arbitrary image filters. We propose decoupled deferred texturing with (1) caching strategies to interactively perform image filtering prior to texture mapping, and (2) for each mipmap level separately to enable a progressive level of abstraction. We demonstrate the potentials of our methods on several applications, including illustrative visualization, focus+context visualization, geometric detail removal, and depth of field. Our system supports frame-to-frame coherence, order-independent transparency, multitexturing, and content-based filtering. © The Authors 2014. This is the authors' version of the work. It is posted here for your personal use. Not for redistribution. The definitive version will be published in Proceedings of the International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe'14). http://dx.doi.org/10.1145/2630099.2630101.}, author = {Semmo, Amir and Döllner, Jürgen}, booktitle = {Proceedings International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe)}, month = 8, pages = {5--14}, title = {Image Filtering for Interactive Level-of-Abstraction Visualization of 3D Scenes}, year = 2014 }
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  High-quality video generation for thin clients - An application for image-based 3D portrayal services. Klimke, Jan (2014). (Vol. 83)
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2014, author = {Klimke, Jan}, booktitle = {Technische Berichte des Hasso-Plattner-Instituts fur Softwaresystemtechnik an der Universitat Potsdam}, title = {High-quality video generation for thin clients - An application for image-based 3D portrayal services}, volume = 83, year = 2014 }
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  Konzepte für eine Service-basierte Systemarchitektur zur Integration, Prozessierung und Analyse von massiven 3D-Punktwolken. Discher, Sören; Richter, Rico; Döllner, Jürgen (2014).
  [ BibTeX ] [ Details ]
   
  @inproceedings{DRD2014, abstract = {Die Nutzung von hoch aufgelösten, räumlich überlappenden und multitemporalen 3D-Punktwolken im Kontext von Geoinformationssystemen stellt hohe Anforderungen an die Leistungsfähigkeit der zugrundeliegenden Software- und Hardwaresysteme. Um angesichts eines weiter zunehmenden Datenaufkommens ein effizientes und wirtschaftliches Arbeiten mit solchen Daten zu ermöglichen, schlagen wir die Nutzung einer service-basierten Software- und Geodateninfrastruktur vor, die eine Erfassung, Aktualisierung und Bereitstellung von 3D-Punktwolken im Sinne eines kontinuierlichen Prozesses ermöglicht. In diesem Beitrag erläutern wir die grundlegenden Anforderungen und den konzeptionellen Aufbau einer entsprechenden Infrastruktur, die unter anderem die bedarfsgerechte Bereitstellung ausgewählter Bereiche einer 3D Punktwolke anhand von semantischen oder temporalen Attributen unterstützt.}, author = {Discher, Sören and Richter, Rico and Döllner, Jürgen}, booktitle = {Tagungsbände der 34. Wissenschaftlich-Technischen Jahrestagung der DGPF}, title = {Konzepte für eine Service-basierte Systemarchitektur zur Integration, Prozessierung und Analyse von massiven 3D-Punktwolken}, year = 2014 }
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  Scalable Multi-Platform Distribution of Spatial 3D Contents. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in International Journal of 3-D Information Modeling, (U. Isikdag, red.) (2014). 3(3) 35-49.
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{KHD2014, abstract = {Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing renderings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. This paper introduces a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: a The complexity of the 3D city model data is decoupled from data transfer complexity b the implementation of client applications is simplified significantly as 3D rendering is encapsulated on server side c 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {International Journal of 3-D Information Modeling}, editor = {Isikdag, U.}, journal = {International Journal of 3-D Information Modeling}, month = 7, number = 3, organization = {HPI}, pages = {35-49}, publisher = {IGI Publishing Hershey, PA, USA}, title = {Scalable Multi-Platform Distribution of Spatial 3D Contents}, volume = 3, year = 2014 }
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  2D and 3D Presentation of Spatial Data: A Systematic Review. Dübel, Steve; Röhlig, Martin; Schumann, Heidrun; Trapp, Matthias (2014).
  [ BibTeX ] [ Details ]
   
  @inproceedings{DRST2014, abstract = {The question whether to use 2D or 3D for data visualization is generally difficult to decide. Two-dimensional and three-dimensional visualization techniques exhibit different advantages and disadvantages related to various perceptual and technical aspects such as occlusion, clutter, distortion, or scalability. To facilitate problem understanding and comparison of existing visualization techniques with regard to these aspects, this report introduces a systematization based on presentation characteristics. It enables a categorization with respect to combinations of static 2D and 3D presentations of attributes and their spatial reference. Further, it complements ex-isting systematizations of data in an effort to formalize a common terminology and theoretical framework for this problem domain. We demonstrate our approach by reviewing different visualization techniques of spatial data according to the presented systematization.}, author = {Dübel, Steve and Röhlig, Martin and Schumann, Heidrun and Trapp, Matthias}, booktitle = {IEEE VIS International Workshop on 3DVis}, month = 11, title = {2D and 3D Presentation of Spatial Data: A Systematic Review}, year = 2014 }

2013 [ nach oben ]

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  Interactive Software Maps for Web-Based Source Code Analysis. Limberger, Daniel; Wasty, Benjamin; Trümper, Jonas; Döllner, Jürgen (2013). 8.
  [ BibTeX ] [ Details ]
   
  @inproceedings{LWTD2013, abstract = {Software maps -- linking rectangular 3D-Treemaps, software system structure, and performance indicators -- are commonly used to support informed decision making in software-engineering processes. A key aspect for this decision making is that software maps provide the structural context required for correct interpretation of these performance indicators. In parallel, source code repositories and collaboration platforms are an integral part of today's software-engineering tool set, but cannot properly incorporate software maps since implementations are only available as stand-alone applications. Hence, software maps are 'disconnected' from the main body of this tool set, rendering their use and provisioning overly complicated, which is one of the main reasons against regular use. We thus present a web-based rendering system for software maps that achieves both fast client-side page load time and interactive frame rates even with large software maps. We significantly reduce page load time by efficiently encoding hierarchy and geometry data for the net transport. Apart from that, appropriate interaction, layouting, and labeling techniques as well as common image enhancements aid evaluation of project-related quality aspects. Metrics provisioning can further be implemented by predefined attribute mappings to simplify communication of project specific quality aspects. The system is integrated into dashboards to demonstrate how our web-based approach makes software maps more accessible to many different stakeholders in software-engineering projects.}, author = {Limberger, Daniel and Wasty, Benjamin and Trümper, Jonas and Döllner, Jürgen}, booktitle = {In Proceedings of the International Web3D Conference}, month = 5, pages = 8, publisher = {ACM}, title = {Interactive Software Maps for Web-Based Source Code Analysis}, year = 2013 }
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  Multi-Perspective Detail+Overview Visualization for 3D Building Exploration. Pasewaldt, Sebastian; Trapp, Matthias; Döllner, Jürgen S. Czanner, Tang, W. (reds.) (2013). 57--64.
  [ BibTeX ] [ Details ]
   
  @inproceedings{PTD2013, abstract = {This paper presents a multi-perspective rendering technique that enables detail+overview visualization and interactive exploration of virtual 3D building model. Virtual 3D building models, as main elements of virtual 3D city models, are used in a growing number of application domains, such as geoanalysis, disaster management and architectural planning. Visualization systems for such building models often rely on perspective or orthogonal projections using a single viewpoint. Therefore, the exploration of a complete model requires a user to change the viewpoint multiple times and to memorize the content of each view to obtain a comprehensive mental model. Since this is usually a time-consuming task, which implies context switching, current visualization systems use multiple viewports to simultaneously depict an object from different perspectives. Our approach extends the idea of multiple viewports by combining two linked views for the interactive exploration of virtual 3D buildings model and their facades. In contrast to traditional approaches, we automatically generate a multi-perspective view that simultaneously depicts all facades of the building in one overview image. This facilitates the process of obtaining overviews and supports fast and direct navigation to various points-of-interest. We describe the concept and implementations of our Multiple-Center-of-Projection camera model for real-time multi-perspective image synthesis. Further, we provide insights into different interaction techniques for linked multi-perspective views and outline approaches of future work.}, author = {Pasewaldt, Sebastian and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of 11th Theory and Practice of Computer Graphics 2013 Conference (TP.CG.2013)}, editor = {Czanner, Silvester and Tang, Wen}, month = 9, pages = {57--64}, publisher = {The Eurographics Association}, title = {Multi-Perspective Detail+Overview Visualization for 3D Building Exploration}, year = 2013 }
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  Object class segmentation of massive 3D point clouds of urban areas using point cloud topology. Richter, Rico; Behrens, Markus; Döllner, Jürgen in International Journal of Remote Sensing (2013). 34(23) 8408-8424.
  [ BibTeX ] [ Details ]
   
  @article{RKD12, abstract = {A large number of remote-sensing techniques and image-based photogrammetric approaches allow an efficient generation of massive 3D point clouds of our physical environment. The efficient processing, analysis, exploration, and visualization of massive 3D point clouds constitute challenging tasks for applications, systems, and workflows in disciplines such as urban planning, environmental monitoring, disaster management, and homeland security. We present an approach to segment massive 3D point clouds according to object classes of virtual urban environments including terrain, building, vegetation, water, and infrastructure. The classification relies on analysing the point cloud topology, it does not require per-point attributes or representative training data. The approach is based on an iterative multi-pass processing scheme, where each pass focuses on different topological features and considers already detected object classes from previous passes. To cope with the massive amount of data, out-of-core spatial data structures and graphics processing unit (GPU)-accelerated algorithms are utilized. Classification results are discussed based on a massive 3D point cloud with almost 5 billion points of a city. The results indicate that object-class-enriched 3D point clouds can substantially improve analysis algorithms and applications as well as enhance visualization techniques.}, author = {Richter, Rico and Behrens, Markus and Döllner, Jürgen}, journal = {International Journal of Remote Sensing}, number = 23, pages = {8408-8424}, title = {Object class segmentation of massive 3D point clouds of urban areas using point cloud topology}, volume = 34, year = 2013 }
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  3D geovisualization services for efficient distribution of 3D geodata. Klimke, J. in Technische Berichte der Hasso-Plattner-Instituts an der Universität Potsdam (2013). (Vol. 76) 63-72.
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2013b, abstract = {Design, implementation, and operation of services for interactive 3D geovisualization are faced with a large number of challenges including (a) processing and integration of massive amounts of heterogeneous and distributed 2D and 3D geodata such as terrain models, buildings models, and thematic georeferenced data, (b) assembling, styling, and rendering 3D map contents according to application requirements and design principles, and (c) interactive provisioning of created 3D maps on mobile devices and thin clients as well as their integration as third-party components into domainspecific web and information systems. This report presents a concept and implementation of a service-oriented platform that addresses these major requirements of 3D web mapping systems. It is based on a separation of concerns for data management, 3D rendering, application logic, and user interaction. The main idea is to divide 3D rendering process into two stages. In the first stage, at the server side, an imagebased representation of the 3D scene is created by means of multi-layered virtual 3D panoramas; in the second stage, at the client side, the 3D scene is interactively reconstructed based on these panoramas. Beside the interactive client introduced earlier, scalable variant for provisioning of virtual 3D city models is described, that utilizes the capabilities of our rendering service for data preparation.}, author = {Klimke, J.}, booktitle = {Proceedings of the 6th Ph.D. Retreat of the HPI Research School on Service}, pages = {63-72}, publisher = {Universitätsverlag Potsdam}, series = {Technische Berichte der Hasso-Plattner-Instituts an der Universität Potsdam}, title = {3D geovisualization services for efficient distribution of 3D geodata}, volume = 76, year = 2013 }
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  Increasing the Usability of Pedestrian Navigation Interfaces by means of Landmark Visibility Analysis. Delikostidis, Ioannis; Engel, Juri; Retsios, Bas; van Elzakker, Corné P.J.M.; Kraak, Menno-Jan; Döllner, Jürgen in The Journal of Navigation (2013). 66(04) 523--537.
  [ BibTeX ] [ Details ]
   
  @article{DEREKD2013, abstract = {Communicating location-specific information to pedestrians is a challenging task which can be aided by user-friendly digital technologies. In this paper, landmark visibility analysis, as a means for developing more usable pedestrian navigation systems is discussed. Using an algorithmic framework for image-based 3D analysis, this method integrates a 3D city model with identified landmarks and produces raster visibility layers for each one. This output enables an Android phone prototype application to indicate the visibility of landmarks from the user’s actual position. Tested in the field, the method achieves sufficient accuracy for the context of use and improves navigation efficiency and effectiveness.}, author = {Delikostidis, Ioannis and Engel, Juri and Retsios, Bas and van Elzakker, Corné P.J.M. and Kraak, Menno-Jan and Döllner, Jürgen}, journal = {The Journal of Navigation}, month = 6, number = {04}, pages = {523--537}, publisher = {The Royal Institute of Navigation}, title = {Increasing the Usability of Pedestrian Navigation Interfaces by means of Landmark Visibility Analysis}, volume = 66, year = 2013 }
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  A Service-Based Concept for Camera Control in 3D Geovirtual Environments. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in Lecture Notes in Geoinformation and Cartography, J. Pouliot, Daniel, S., Hubert, F., Zamyadi, A. (reds.) (2013). 101--118.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Klimke2013, address = {Berlin, Heidelberg}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Progress and New Trends in 3D Geoinformation Sciences}, editor = {Pouliot, Jacynthe and Daniel, Sylvie and Hubert, Frédéric and Zamyadi, Alborz}, pages = {101--118}, publisher = {Springer Berlin Heidelberg}, series = {Lecture Notes in Geoinformation and Cartography}, title = {A Service-Based Concept for Camera Control in 3D Geovirtual Environments}, year = 2013 }
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  Scalable Multi-Platform Distribution of Spatial 3D Contents. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences (2013). II-2/W1 193--200.
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{klimke2013scalable, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, journal = {ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences}, pages = {193--200}, title = {Scalable Multi-Platform Distribution of Spatial 3D Contents}, volume = {II-2/W1}, year = 2013 }
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  Concepts and techniques for integration, analysis and visualization of massive 3D point clouds. Richter, Rico; Döllner, Jürgen in Computers, Environment and Urban Systems (2013). 45 114-124.
  [ BibTeX ] [ Details ]
   
  @article{RD13, abstract = {Remote sensing methods, such as LiDAR and image-based photogrammetry, are established approaches for capturing the physical world. Professional and low-cost scanning devices are capable of generating dense 3D point clouds. Typically, these 3D point clouds are preprocessed by GIS and are then used as input data in a variety of applications such as urban planning, environmental monitoring, disaster management, and simulation. The availability of area-wide 3D point clouds will drastically increase in the future due to the availability of novel capturing methods (e.g., driver assistance systems) and low-cost scanning devices. Applications, systems, and workflows will therefore face large collections of redundant, up-to-date 3D point clouds and have to cope with massive amounts of data. Hence, approaches are required that will efficiently integrate, update, manage, analyze, and visualize 3D point clouds. In this paper, we define requirements for a system infrastructure that enables the integration of 3D point clouds from heterogeneous capturing devices and different timestamps. Change detection and update strategies for 3D point clouds are presented that reduce storage requirements and offer new insights for analysis purposes. We also present an approach that attributes 3D point clouds with semantic information (e.g., object class category information), which enables more effective data processing, analysis, and visualization. Out-of-core real-time rendering techniques then allow for an interactive exploration of the entire 3D point cloud and the corresponding analysis results. Web-based visualization services are utilized to make 3D point clouds available to a large community. The proposed concepts and techniques are designed to establish 3D point clouds as base datasets, as well as rendering primitives for analysis and visualization tasks, which allow operations to be performed directly on the point data. Finally, we evaluate the presented system, report on its applications, and discuss further research challenges.}, author = {Richter, Rico and Döllner, Jürgen}, journal = {Computers, Environment and Urban Systems}, pages = {114-124}, title = {Concepts and techniques for integration, analysis and visualization of massive 3D point clouds}, volume = 45, year = 2013 }
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  Out-of-Core GPU-based Change Detection in Massive 3D Point Clouds. Richter, Rico; Kyprianidis, Jan Eric; Döllner, Jürgen in Transactions in GIS (2013). 17(5) 724-741.
  [ BibTeX ] [ Details ]
   
  @article{RKD12, abstract = {If sites, cities, and landscapes are captured at different points in time using technology such as LiDAR, large collections of 3D point clouds result. Their efficient storage, processing, analysis, and presentation constitute a challenging task because of limited computation, memory, and time resources. In this work, we present an approach to detect changes in massive 3D point clouds based on an out-of-core spatial data structure that is designed to store data acquired at different points in time and to efficiently attribute 3D points with distance information. Based on this data structure, we present and evaluate different processing schemes optimized for performing the calculation on the CPU and GPU. In addition, we present a point-based rendering technique adapted for attributed 3D point clouds, to enable effective out-of-core real-time visualization of the computation results. Our approach enables conclusions to be drawn about temporal changes in large highly accurate 3D geodata sets of a captured area at reasonable preprocessing and rendering times. We evaluate our approach with two data sets from different points in time for the urban area of a city, describe its characteristics, and report on applications.}, author = {Richter, Rico and Kyprianidis, Jan Eric and Döllner, Jürgen}, journal = {Transactions in GIS}, number = 5, pages = {724-741}, title = {Out-of-Core GPU-based Change Detection in Massive 3D Point Clouds}, volume = 17, year = 2013 }
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  SyncTrace: Visual Thread-Interplay Analysis. Karran, Benjamin; Trümper, Jonas; Döllner, Jürgen (2013). 10.
  [ BibTeX ] [ Details ]
   
  @inproceedings{KTD2013, abstract = {In software comprehension, program traces are important to gain insight into certain aspects of concurrent runtime behavior, e.g., thread-interplay. Here, key tasks are finding usages of blocking operations, such as synchronization and I/O operations, assessing temporal order of such operations, and analyzing their effects. This is a hard task for large and complex program traces due to their size and number of threads involved. In this paper, we present SyncTrace, a new visualization technique based on (bended) activity diagrams and edge bundles that allows for parallel analysis of multiple threads and their inter-thread correspondences. We demonstrate how the technique, implemented as a tool, can be applied on real-world trace datasets to support understanding concurrent behavior.}, author = {Karran, Benjamin and Trümper, Jonas and Döllner, Jürgen}, booktitle = {Proceedings (electronic) of the 1st Working Conference on Software Visualization (VISSOFT)}, month = 9, pages = 10, publisher = {IEEE Computer Society}, title = {SyncTrace: Visual Thread-Interplay Analysis}, year = 2013 }
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  Evaluating the Perceptual Impact of Rendering Techniques on Thematic Color Mappings in 3D Virtual Environments. Engel, Juri; Semmo, Amir; Trapp, Matthias; Döllner, Jürgen J. F. Michael Bronstein, Hormann, K. (reds.) (2013). 25-32.
  [ BibTeX ] [ Details ]
   
  @inproceedings{ESTD2013, abstract = {Using colors for thematic mapping is a fundamental approach in visualization, and has become essential for 3D virtual environments to effectively communicate multidimensional, thematic information. Preserving depth cues within these environments to emphasize spatial relations between geospatial features remains an important issue.A variety of rendering techniques have been developed to preserve depth cues in 3D information visualization, including shading, global illumination, and image stylization. However, these techniques alter color values, which may lead to ambiguity in a color mapping and loss of information. Depending on the applied rendering techniques and color mapping, this loss should be reduced while still preserving depth cues when communicating thematic information. This paper presents the results of a quantitative and qualitative user study that evaluates the impact of rendering techniques on information and spatial perception when using visualization of thematic data in 3D virtual environments. We report the results of this study with respect to four perception-related tasks, showing significant differences in error rate and task completion time for different rendering techniques and color mappings.}, author = {Engel, Juri and Semmo, Amir and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of 18th International Workshop on Vision, Modeling and Visualization (VMV 2013)}, editor = {Michael Bronstein, Jean Favre and Hormann, Kai}, month = 9, pages = {25-32}, publisher = {The Eurographics Association}, title = {Evaluating the Perceptual Impact of Rendering Techniques on Thematic Color Mappings in 3D Virtual Environments}, year = 2013 }
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  State of the ‘Art’: A Taxonomy of Artistic Stylization Techniques for Images and Video. Kyprianidis, Jan Eric; Collomosse, John; Wang, Tinghuai; Isenberg, Tobias in IEEE Transactions on Visualization and Computer Graphics (2013). 19(5) 866--885.
  [ BibTeX ] [ Details ]
   
  @article{KCWI13, abstract = {This paper surveys the field of non-photorealistic rendering (NPR), focusing on techniques for transforming 2D input (images and video) into artistically stylized renderings. We first present a taxonomy of the 2D NPR algorithms developed over the past two decades, structured according to the design characteristics and behavior of each technique. We then describe a chronology of development from the semi-automatic paint systems of the early nineties, through to the automated painterly rendering systems of the late nineties driven by image gradient analysis. Two complementary trends in the NPR literature are then addressed, with reference to our taxonomy. First, the fusion of higher level computer vision and NPR, illustrating the trends toward scene analysis to drive artistic abstraction and diversity of style. Second, the evolution of local processing approaches toward edge-aware filtering for real-time stylization of images and video. The survey then concludes with a discussion of open challenges for 2D NPR identified in recent NPR symposia, including topics such as user and aesthetic evaluation.}, author = {Kyprianidis, Jan Eric and Collomosse, John and Wang, Tinghuai and Isenberg, Tobias}, journal = {IEEE Transactions on Visualization and Computer Graphics}, number = 5, pages = {866--885}, title = {State of the ‘Art’: A Taxonomy of Artistic Stylization Techniques for Images and Video}, volume = 19, year = 2013 }
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  Interactive Rendering Techniques for Focus+Context Visualization of 3D Geovirtual Environments. Technical Report (PhD dissertation), Trapp, Matthias PhD thesis, Hasso-Plattner-Institut für Softwaresystemtechnik GmbH, Prof.-Dr.-Helmert-Str. 2-3, D-14482 Potsdam. (2013).
  [ BibTeX ] [ Details ]
   
  @phdthesis{T2013, abstract = {This thesis introduces a collection of new real-time rendering techniques and applications for focus+context visualization of interactive 3D geovirtual environments such as virtual 3D city and landscape models. These environments are generally characterized by a large number of objects and are of high complexity with respect to geometry and textures. For these reasons, their interactive 3D rendering represents a major challenge. Their 3D depiction implies a number of weaknesses such as occlusions, cluttered image contents, and partial screen-space usage. To overcome these limitations and, thus, to facilitate the effective communication of geo-information, principles of focus+context visualization can be used for the design of real-time 3D rendering techniques for 3D geovirtual environments (see Figure). In general, detailed views of a 3D geovirtual environment are combined seamlessly with abstracted views of the context within a single image. To perform the real-time image synthesis required for interactive visualization, dedicated parallel processors (GPUs) for rasterization of computer graphics primitives are used. For this purpose, the design and implementation of appropriate data structures and rendering pipelines are necessary. The contribution of this work comprises the following five real-time rendering methods: The rendering technique for 3D generalization lenses enables the combination of different 3D city geometries (e.g., generalized versions of a 3D city model) in an single image in real time. The method is based on a generalized and fragment-precise clipping approach, which uses a compressible, raster-based data structure. It enables the combination of detailed views in the focus area with the representation of abstracted variants in the context area. The rendering technique for the interactive visualization of dynamic raster data in 3D geovirtual environments facilitates the rendering of 2D surface lenses. It enables a flexible combination of different raster layers (e.g., aerial images or videos) using projective texturing for decoupling image and geometry data. Thus, various overlapping and nested 2D surface lenses of different contents can be visualized interactively. The interactive rendering technique for image-based deformation of 3D geovirtual environments enables the real-time image synthesis of non-planar projections, such as cylindrical and spherical projections, as well as multi-focal 3D fisheye-lenses and the combination of planar and non-planar projections. The rendering technique for view-dependent multi-perspective views of 3D geovirtual environments, based on the application of global deformations to the 3D scene geometry, can be used for synthesizing interactive panorama maps to combine detailed views close to the camera (focus) with abstract views in the background (context). This approach reduces occlusions, increases the usage the available screen space, and reduces the overload of image contents. The object-based and image-based rendering techniques for highlighting objects and focus areas inside and outside the view frustum facilitate preattentive perception. The concepts and implementations of interactive image synthesis for focus+context visualization and their selected applications enable a more effective communication of spatial information, and provide building blocks for design and development of new applications and systems in the field of 3D geovirtual environments.}, address = {Hasso-Plattner-Institut für Softwaresystemtechnik GmbH, Prof.-Dr.-Helmert-Str. 2-3, D-14482 Potsdam}, author = {Trapp, Matthias}, month = 7, school = {Hasso Plattner Institut, University Potsdam}, title = {Interactive Rendering Techniques for Focus+Context Visualization of 3D Geovirtual Environments}, year = 2013 }
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  A Service-Based Concept for Camera Control in 3D Geovirtual Environments. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in Lecture Notes in Geoinformation and Cartography, J. Pouliot, Daniel, S., Hubert, F., Zamyadi, A. (reds.) (2013). 101--118.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Klimke2013, address = {Berlin, Heidelberg}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Progress and New Trends in 3D Geoinformation Sciences}, editor = {Pouliot, Jacynthe and Daniel, Sylvie and Hubert, Frédéric and Zamyadi, Alborz}, pages = {101--118}, publisher = {Springer Berlin Heidelberg}, series = {Lecture Notes in Geoinformation and Cartography}, title = {A Service-Based Concept for Camera Control in 3D Geovirtual Environments}, year = 2013 }
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  Interactive Rendering of Complex 3D-Treemaps. Trapp, Matthias; Hahn, Sebastian; Döllner, Jürgen S. Coquillart, Andujar, C., Laramee, R. S., Kerren, A., Braz, J. (reds.) (2013). 165-175.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TSD2013, abstract = {3D-Treemaps are an important visualization technique for hierarchical views. In contrast to 2D-Treemaps, height can be used to map one additional attribute of the data items. Using the Treemap technique in combination with large datasets (more than 500k) a fast rendering and interaction techniques that are beyond collapsing/uncollapsing nodes is still one of the main challenges. This paper presents a novel rendering technique that enables the image synthesis of geometrical complex 3D-Treemaps in real-time. The fully hardware accelerated approach is based on shape generation using geometry shaders. This approach offers increased rendering performance and low update latency compared to existing techniques and through it enables new real-time interaction techniques to large datasets.}, author = {Trapp, Matthias and Hahn, Sebastian and Döllner, Jürgen}, booktitle = {Proceedings of the 8th International Conference on Computer Graphics Theory and Applications (GRAPP 2013)}, editor = {Coquillart, Sabine and Andujar, Carlos and Laramee, Robert S. and Kerren, Andreas and Braz, José}, month = 2, pages = {165-175}, publisher = {SCITEPRESS – Science and Technology Publications}, title = {Interactive Rendering of Complex 3D-Treemaps}, year = 2013 }
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  Towards Visualizing Geo-Referenced Climate Networks. Buschmann, Stefan; Nocke, Thomas; Tominski, Christian; Döllner, Jürgen (2013).
  [ BibTeX ] [ Details ]
   
  @inproceedings{Buschmann2013b, abstract = {In the last few years, network construction from climate data has developed to a promising analysis method. We discuss challenges for the interactive visual analysis of such geo-referenced networks and present first ideas for addressing the challenges. In particular, we present visualizations of 3D geo-spatial networks and of large networks within cartographic contexts.}, author = {Buschmann, Stefan and Nocke, Thomas and Tominski, Christian and Döllner, Jürgen}, booktitle = {Proceedings of Workshop GeoViz Hamburg 2013}, title = {Towards Visualizing Geo-Referenced Climate Networks}, year = 2013 }
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  Real-Time Rendering of Water Surfaces with Cartography-Oriented Design. Semmo, Amir; Kyprianidis, Jan Eric; Trapp, Matthias; Döllner, Jürgen in Proceedings International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe) (2013). 5--14.
  [ BibTeX ] [ Details ]
   
  @inproceedings{SKTD13, abstract = {More than 70% of the Earth's surface is covered by oceans, seas, and lakes, making water surfaces one of the primary elements in geospatial visualization. Traditional approaches in computer graphics simulate and animate water surfaces in the most realistic ways. However, to improve orientation, navigation, and analysis tasks within 3D virtual environments, these surfaces need to be carefully designed to enhance shape perception and land-water distinction. We present an interactive system that renders water surfaces with cartography-oriented design using the conventions of mapmakers. Our approach is based on the observation that hand-drawn maps utilize and align texture features to shorelines with non-linear distance to improve figure-ground perception and express motion. To obtain local orientation and principal curvature directions, first, our system computes distance and feature-aligned distance maps. Given these maps, waterlining, water stippling, contour-hatching, and labeling are applied in real-time with spatial and temporal coherence. The presented methods can be useful for map exploration, landscaping, urban planning, and disaster management, which is demonstrated by various real-world virtual 3D city and landscape models. © ACM, 2013. This is the authors' version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in Proceedings of the International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe'13). http://dx.doi.org/10.1145/2487276.2487277.}, author = {Semmo, Amir and Kyprianidis, Jan Eric and Trapp, Matthias and Döllner, Jürgen}, month = 7, pages = {5--14}, series = {Proceedings International Symposium on Computational Aesthetics in Graphics, Visualization, and Imaging (CAe)}, title = {Real-Time Rendering of Water Surfaces with Cartography-Oriented Design}, year = 2013 }
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  Photorealistic Rendering of Day and Night Sky Phenomena in Interactive 3D Geovirtual Environments. Limberger,; Daniel, (2013).
  [ BibTeX ] [ Details ]
   
  @other{L13, author = {Limberger and Daniel}, month = 2, title = {Photorealistic Rendering of Day and Night Sky Phenomena in Interactive 3D Geovirtual Environments}, year = 2013 }
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  Interactive Projective Texturing for Non-Photorealistic Shading of Technical 3D Models. Lux, Roland; Trapp, Matthias; Semmo, Amir; Döllner, Jürgen S. Czanner, Tang, W. (reds.) (2013). 101--108.
  [ BibTeX ] [ Details ]
   
  @inproceedings{LTSD13, abstract = {This paper presents a novel interactive rendering technique for creating and editing shadings for man-made objects in technical 3D visualizations. In contrast to shading approaches that use intensities computed based on surface normals (e.g., Phong, Gooch, Toon shading), the presented approach uses one-dimensional gradient textures, which can be parametrized and interactively manipulated based on per-object bounding volume approximations. The fully hardware-accelerated rendering technique is based on projective texture mapping and customizable intensity transfer functions. A provided performance evaluation shows comparable results to traditional normal-based shading approaches. The work also introduce simple direct-manipulation metaphors that enables interactive user control of the gradient texture alignment and intensity transfer functions.}, author = {Lux, Roland and Trapp, Matthias and Semmo, Amir and Döllner, Jürgen}, booktitle = {Proceedings of 11th Theory and Practice of Computer Graphics 2013 Conference (TP.CG.2013)}, editor = {Czanner, Silvester and Tang, Wen}, month = 9, pages = {101--108}, publisher = {The Eurographics Association}, title = {Interactive Projective Texturing for Non-Photorealistic Shading of Technical 3D Models}, year = 2013 }
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  2.5D Clip-Surfaces for Technical Visualization. Trapp, Matthias; Döllner, Jürgen in Journal of WSCG, (V. Skala, red.) (2013). 21(1) 89-96.
  [ BibTeX ] [ Details ]
   
  @article{TD2013, abstract = {The concept of clipping planes is well known in computer graphics and can be used to create cut-away views. But clipping against just analytical defined planes is not always suitable for communicating every aspect of such visualization. For example, in hand-drawn technical illustrations, artists tend to communicate the difference between a cut and a model feature by using non-regular, sketchy cut lines instead of straight ones. To enable this functionality in computer graphics, this paper presents a technique for applying 2.5D clip-surfaces in real-time. Therefore, the clip plane equation is extended with an additional offset map, which can be represented by a texture map that contains height values. Clipping is then performed by varying the clip plane equation with respect to such an offset map. Further, a capping technique is proposed that enables the rendering of caps onto the clipped area to convey the impression of solid material. It avoids a re-meshing of a solid polygonal mesh after clipping is performed. Our approach is pixel precise, applicable in real-time, and takes fully advantage of graphics accelerators.}, address = {Na Mazinach 9, CZ 322 00 Plzen, Czech Republic}, author = {Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of WSCG 2013: 21st International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision}, editor = {Skala, Václav}, journal = {Journal of WSCG}, month = 6, number = 1, pages = {89-96}, publisher = {Union Agency}, title = {2.5D Clip-Surfaces for Technical Visualization}, volume = 21, year = 2013 }
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  Multiscale Visual Comparison of Execution Traces. Trümper, Jonas; Döllner, Jürgen; Telea, Alexandru (2013). 53-62.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TDT2013, abstract = {Understanding the execution of programs by means of program traces is a key strategy in software comprehension. An important task in this context is comparing two traces in order to find similarities and differences in terms of executed code, execution order, and execution duration. For large and complex program traces, this is a difficult task due to the cardinality of the trace data. In this paper, we propose a new visualization method based on icicle plots and edge bundles. We address visual scalability by several multiscale visualization metaphors, which help users navigating from the main differences between two traces to intermediate structural-difference levels, and, finally fine-grained function call levels. We show how our approach, implemented in a tool called TraceDiff, is applicable in several scenarios for trace difference comprehension on real-world trace datasets.}, author = {Trümper, Jonas and Döllner, Jürgen and Telea, Alexandru}, booktitle = {Proceedings of the International Conference on Program Comprehension}, month = 5, pages = {53-62}, publisher = {IEEE Computer Society}, title = {Multiscale Visual Comparison of Execution Traces}, year = 2013 }

2012 [ nach oben ]

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  Concepts for Automatic Generalization of Virtual 3D Landscape Models. Glander, Tassilo; Trapp, Matthias; Döllner, Jürgen in gis.SCIENCE (2012). 25(1) 18-23.
  [ BibTeX ] [ Details ]
   
  @article{GTD12, abstract = {This paper discusses concepts for the automatic generalization of virtual 3D landscape models. As complexity, heterogeneity, and diversity of geodata that constitute landscape models are constantly growing, the need for landscape models that generalize their contents to a consistent, coherent level-of-abstraction and information density becomes an essential requirement for applications such as in conceptual landscape design, simulation and analysis, and mobile mapping. We discuss concepts of generalization and working principles as well as the concept of level-of-abstraction. We furthermore present three exemplary automated techniques for generalizing 3D landscape models, including a geometric generalization technique that generates discrete iso-surfaces of 3D terrain models in real-time, a geometric generalization technique for site and building models, and a real-time generalization lens technique.}, author = {Glander, Tassilo and Trapp, Matthias and Döllner, Jürgen}, journal = {gis.SCIENCE}, month = 3, note = {Cover Image}, number = 1, pages = {18-23}, publisher = {Wichmann Verlag}, title = {Concepts for Automatic Generalization of Virtual 3D Landscape Models}, volume = 25, year = 2012 }
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  Server-based rendering of large 3D scenes for mobile devices using G-buffer cube maps. Doellner, Jürgen; Hagedorn, Benjamin; Klimke, Jan in Web3D '12 (2012). 97--100.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{DHK2012, address = {New York, NY, USA}, author = {Doellner, Jürgen and Hagedorn, Benjamin and Klimke, Jan}, booktitle = {Proceedings of the 17th International Conference on 3D Web Technology}, pages = {97--100}, publisher = {ACM}, series = {Web3D '12}, title = {Server-based rendering of large 3D scenes for mobile devices using G-buffer cube maps}, year = 2012 }
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  A Service-Oriented Platform for Interactive 3D Web Mapping. Klimke, J.; Hagedorn, B.; Doellner, J. M. Jobst (red.) (2012). 127--139.
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2012, address = {Vienna}, author = {Klimke, J. and Hagedorn, B. and Doellner, J.}, booktitle = {Service-Oriented Mapping}, editor = {Jobst, M.}, pages = {127--139}, publisher = {JOBSTMedia 2012}, title = {A Service-Oriented Platform for Interactive 3D Web Mapping}, year = 2012 }
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  Extended hybrid meshing algorithm for multiresolution terrain models. Paredes, E.G.; Bóo, M.; Amor, M.; Bruguera, J.D.; Döllner, J. in International Journal of Geographical Information Science (2012). 26(5) 771--793.
  [ BibTeX ] [ Details ]
   
  @article{PBABD2012, abstract = {Hybrid terrains are a convenient approach for the representation of digital terrain models, integrating heterogeneous data from different sources. In this article, we present a general, efficient scheme for achieving interactive level-of-detail rendering of hybrid terrain models, without the need for a costly preprocessing or resampling of the original data. The presented method works with hybrid digital terrains combining regular grid data and local high-resolution triangulated irregular networks. Since grid and triangulated irregular network data may belong to different datasets, a straightforward combination of both geometries would lead to meshes with holes and overlapping triangles. Our method generates a single multiresolution model integrating the different parts in a coherent way, by performing an adaptive tessellation of the region between their boundaries. Hence, our solution is one of the few existing approaches for integrating different multiresolution algorithms within the same terrain model, achieving a simple interactive rendering of complex hybrid terrains.}, author = {Paredes, E.G. and Bóo, M. and Amor, M. and Bruguera, J.D. and Döllner, J.}, journal = {International Journal of Geographical Information Science}, number = 5, pages = {771--793}, title = {Extended hybrid meshing algorithm for multiresolution terrain models}, volume = 26, year = 2012 }
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  A Service-Oriented Platform for Interactive 3D Web Mapping. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen (2012).
  [ BibTeX ] [ Details ]
   
  @inproceedings{KHD2012, abstract = {Design, implementation, and operation of interactive 3D map services are faced with a large number of challenges including (a) processing and integration of massive amounts of heterogeneous and distributed 2D and 3D geodata such as terrain models, buildings models, and thematic georeferenced data, (b) assembling, styling, and rendering 3D map contents according to application requirements and design principles, and (c) interactive provisioning of created 3D maps on mobile devices and thin clients as well as their integration as third-party components into domain-specific web and information systems. This paper discusses concept and implementation of a service-oriented platform that addresses these major requirements of 3D web mapping systems. It is based on a separation of concerns for data management, 3D rendering, application logic, and user interaction. The main idea is to divide 3D rendering process into two stages. In the first stage, at the server side, we construct an image-based, omni-directional approximation of the 3D scene by means of multi-layered virtual 3D panoramas, in the second stage, at the client side, we interactively reconstruct the 3D scene based on the panorama. We demonstrate the prototype implementation for real-time 3D rendering service and related iOS 3D client applications. In our case study, we show how to interactively visualize a complex, large-scale 3D city model based on our service-oriented platform.}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the Symposium of Service-oriented Mapping}, month = 11, title = {A Service-Oriented Platform for Interactive 3D Web Mapping}, year = 2012 }
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  Concepts for Cartography-Oriented Visualization of Virtual 3D City Models. Semmo, Amir; Hildebrandt, Dieter; Trapp, Matthias; Döllner, Jürgen in Photogrammetrie - Fernerkundung - Geoinformation (PFG) (2012). (4) 455-465.
  [ BibTeX ] [ Details ]
   
  @article{SHTD2012, abstract = {Virtual 3D city models serve as an effective medium with manifold applications in geoinformation systems and services. To date, most 3D city models are visualized using photorealistic graphics. But an effective communication of geoinformation significantly depends on how important information is designed and cognitively processed in the given application context. One possibility to visually emphasize important information is based on non-photorealistic rendering, which comprehends artistic depiction styles and is characterized by its expressiveness and communication aspects. However, a direct application of non-photorealistic rendering techniques primarily results in monotonic visualization that lacks cartographic design aspects. In this work, we present concepts for cartography-oriented visualization of virtual 3D city models. These are based on coupling non-photorealistic rendering techniques and semantics-based information for a user, context, and media-dependent representation of thematic information. This work highlights challenges for cartography-oriented visualization of 3D geovirtual environments, presents stylization techniques and discusses their applications and ideas for a standardized visualization. In particular, the presented concepts enable a real-time and dynamic visualization of thematic geoinformation.}, address = {Johannesstrasse 3A, D-70176 Stuttgart, Germany}, author = {Semmo, Amir and Hildebrandt, Dieter and Trapp, Matthias and Döllner, Jürgen}, journal = {Photogrammetrie - Fernerkundung - Geoinformation (PFG)}, number = 4, pages = {455-465}, publisher = {E. Schweizerbart'sche Verlagsbuchhandlung}, title = {Concepts for Cartography-Oriented Visualization of Virtual 3D City Models}, year = 2012 }
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  A Service-Oriented Platform for Interactive 3D Web Mapping. Klimke, J.; Hagedorn, B.; Doellner, J. M. Jobst (red.) (2012). 127--139.
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2012, address = {Vienna}, author = {Klimke, J. and Hagedorn, B. and Doellner, J.}, booktitle = {Service-Oriented Mapping}, editor = {Jobst, M.}, pages = {127--139}, publisher = {JOBSTMedia 2012}, title = {A Service-Oriented Platform for Interactive 3D Web Mapping}, year = 2012 }
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  A Service-Based Concept for Camera Control in 3D Geovirtual Environments. Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen (2012).
  [ BibTeX ] [ Details ]
   
  @inproceedings{KHD12, abstract = {3D geovirtual environments (3D GeoVEs) such as virtual 3D city models serve as integration platforms for complex geospatial information and facilitate effective use and communication of that information. Recent developments towards standards and service-based, interactive 3D geovisualization systems enable the large-scale distribution of 3D GeoVEs also by thin client applications that work on mobile devices or in web browsers. To construct such systems, 3D portrayal services can be used as building blocks for service-based rendering. Service-based approaches for 3D user interaction, however, have not been formalized and specified to a similar degree. In this paper, we present a concept for service-based 3D camera control as a key element of 3D user interaction used to explore and manipulate 3D GeoVEs and their objects. It is based on the decomposition of 3D user interaction functionality into a set of services that can be flexibly combined to build automated, assisting, and application-specific 3D user interaction tools, which fit into service-oriented architectures of GIS and SDI based IT solutions. We discuss 3D camera techniques, categories of 3D camera tasks, and derive a collection of general-purpose 3D interaction services. We also explain how to eficiently compose these services and discuss their impact on the architecture of service-based visualization systems. Furthermore, we outline an example of a distributed 3D geovisualization system that shows how the concepts can be applied applications based on virtual 3D city models.}, author = {Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the 7th 3D GeoInfo Conference 2012}, title = {A Service-Based Concept for Camera Control in 3D Geovirtual Environments}, year = 2012 }
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  Datenintegration in dienstbasierte 3D-Geovisualisierungssysteme für mobile Geräte. Klimke, Jan; Döllner, Jürgen (2012).
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2012a, author = {Klimke, Jan and Döllner, Jürgen}, booktitle = {Tagungsbände der 32. Wissenschaftlich-Technischen Jahrestagung der DGPF}, title = {Datenintegration in dienstbasierte 3D-Geovisualisierungssysteme für mobile Geräte}, year = 2012 }
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  Interactive Visualization of Generalized Virtual 3D City Models using Level-of-Abstraction Transitions. Semmo, Amir; Trapp, Matthias; Kyprianidis, Jan Eric; Döllner, Jürgen in Computer Graphics Forum (2012). 31(3) 885--894.
  [ BibTeX ] [ Details ]
   
  @article{STKD12, abstract = {Virtual 3D city models play an important role in the communication of complex geospatial information in a growing number of applications, such as urban planning, navigation, tourist information, and disaster management. In general, homogeneous graphic styles are used for visualization. For instance, photorealism is suitable for detailed presentations, and non-photorealism or abstract stylization is used to facilitate guidance of a viewer's gaze to prioritized information. However, to adapt visualization to different contexts and contents and to support saliency-guided visualization based on user interaction or dynamically changing thematic information, a combination of different graphic styles is necessary. Design and implementation of such combined graphic styles pose a number of challenges, specifically from the perspective of real-time 3D visualization. In this paper, the authors present a concept and an implementation of a system that enables different presentation styles, their seamless integration within a single view, and parametrized transitions between them, which are defined according to tasks, camera view, and image resolution. The paper outlines potential usage scenarios and application fields together with a performance evaluation of the implementation.}, author = {Semmo, Amir and Trapp, Matthias and Kyprianidis, Jan Eric and Döllner, Jürgen}, journal = {Computer Graphics Forum}, note = {Proceedings EuroVis 2012}, number = 3, pages = {885--894}, title = {Interactive Visualization of Generalized Virtual 3D City Models using Level-of-Abstraction Transitions}, volume = 31, year = 2012 }
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  Dichte- und Distanzanalyse massiver raumzeitlicher Bewegungsdaten. Buschmann, Stefan; Döllner, Jürgen (2012). 67-74.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BD12, abstract = {Dieser Beitrag stellt einen Ansatz zur interaktiven Analyse massiver raumzeitlicher Bewegungsdaten vor. Der Ansatz ermöglicht es, auf Bewegungstrajektorien basierende Daten interaktiv zu visualisieren und mit flächenbasierten Verfahren auf Basis von Dichte- und Distanzkarten zu analysieren. Ziel ist es, dadurch unterschiedliche raumzeitliche Phänomene in massiven Bewegungsdaten aufspüren, extrahieren und untersuchen zu können. Diese Verfahren stellen generische Basisfunktionen für die Auswertung massiver raumzeitlicher Bewegungsdaten, z. B. für entscheidungsunterstützende Geoinformationssysteme, bereit. Anwendungsfelder umfassen die Echtzeit-Bewegungsüberwachung und die Auswertung von Bewegungsdaten, z. B. im Straßen-, Schiffs- oder Flugverkehr.}, author = {Buschmann, Stefan and Döllner, Jürgen}, booktitle = {Geoinformatik 2012 - „Mobilität und Umwelt“}, month = 3, pages = {67-74}, publisher = {Shaker Verlag}, title = {Dichte- und Distanzanalyse massiver raumzeitlicher Bewegungsdaten}, year = 2012 }
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  XDoG: An eXtended difference-of-Gaussians compendium including advanced image stylization. Winnemöller, Holger; Kyprianidis, Jan Eric; Olsen, Sven C. in Computers & Graphics (2012). 36(6) 740-753.
  [ BibTeX ] [ Details ]
   
  @article{WKO12, abstract = {Recent extensions to the standard Difference-of-Gaussians (DoG) edge detection operator have rendered it less susceptible to noise and increased its aesthetic appeal. Despite these advances, the technical subtleties and stylistic potential of the DoG operator are often overlooked. This paper offers a detailed review of the DoG operator and its extensions, highlighting useful relationships to other image processing techniques. It also presents many new results spanning a variety of styles, including pencil-shading, pastel, hatching, and woodcut. Additionally, we demonstrate a range of subtle artistic effects, such as ghosting, speed-lines, negative edges, indication, and abstraction, all of which are obtained using an extended DoG formulation, or slight modifications thereof. In all cases, the visual quality achieved by the extended DoG operator is comparable to or better than those of systems dedicated to a single style.}, author = {Winnemöller, Holger and Kyprianidis, Jan Eric and Olsen, Sven C.}, journal = {Computers & Graphics}, number = 6, pages = {740-753}, title = {XDoG: An eXtended difference-of-Gaussians compendium including advanced image stylization}, volume = 36, year = 2012 }
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  Server-based rendering of large 3D scenes for mobile devices using G-buffer cube maps. Doellner, Jürgen; Hagedorn, Benjamin; Klimke, Jan in Web3D '12 (2012). 97--100.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{DHK2012, address = {New York, NY, USA}, author = {Doellner, Jürgen and Hagedorn, Benjamin and Klimke, Jan}, booktitle = {Proceedings of the 17th International Conference on 3D Web Technology}, pages = {97--100}, publisher = {ACM}, series = {Web3D '12}, title = {Server-based rendering of large 3D scenes for mobile devices using G-buffer cube maps}, year = 2012 }
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  An Immersive Visualization System for Virtual 3D City Models. Engel, Juri; Pasewaldt, Sebastian; Trapp, Matthias; Döllner, Jürgen (2012).
  [ BibTeX ] [ Details ]
   
  @inproceedings{EPTD12, abstract = {Virtual 3D city models are essential visualization tools for effective communication of complex urban spatial information. Immersive visualization of virtual 3D city models offers an intuitive access to and an effective way of realization of urban spatial information, enabling new collaborative applications and decision-support systems. This paper discusses techniques for and usage of fully immersive environments for visualizing virtual 3D city models by advanced 3D rendering techniques. Fully immersive environments imply a number of specific requirements for both hardware and software, which are discussed in detail. Further, we identify and outline conceptual and technical challenges as well as possible solution approaches by visualization system prototypes for large-scale, fully immersive environments. We evaluate the presented concepts using two application examples and discuss the results.}, author = {Engel, Juri and Pasewaldt, Sebastian and Trapp, Matthias and Döllner, Jürgen}, booktitle = {20th International Conference on Geoinformatics (GEOINFORMATICS), 2012}, month = 6, publisher = {IEEE GRSS}, title = {An Immersive Visualization System for Virtual 3D City Models}, year = 2012 }
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  OGC 3D Portrayal Interoperatiliy Experiment Final Report. Technical Report (OGC 12-075), Schilling, Arne; Hagedorn, Benjamin; Coors, Volker (2012).
  [ BibTeX ] [ URL ] [ Details ]
   
  @techreport{schilling2012portrayal, abstract = {This report describes the setup, experiments, results and issues generated by the 3D Portrayal Interoperability Experiment (3DPIE), carried out as an activity of the 3D Information Management Domain Working Group (3DIM). The 3DPIE is designed to test and demonstrate different approaches for service-based 3D portrayal based on the drafts for the candidate standards for 3D portrayal, Web 3D Service (W3DS) and Web View Service (WVS). This document [...] contains technical details on processing 3D information in an OGC service environment as well as best practices on how to portray large data sets in urban planning scenarios, taking into account architectures and capabilities of interactive 3D graphics. Especially Web 3D Service and Web View Service, two draft standards (published as OGC discussions paper), have been in the focus of 3DPIE.}, editor = {Schilling, Arne and Hagedorn, Benjamin and Coors, Volker}, institution = {Open Geospatial Consortium}, month = {aug}, number = {OGC 12-075}, title = {OGC 3D Portrayal Interoperatiliy Experiment Final Report}, type = {OGC Engineering Report}, year = 2012 }
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  ViewFusion: Correlating Structure and Activity Views for Execution Traces. Trümper, Jonas; Telea, Alexandru; Döllner, Jürgen (2012). 45-52.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TTD2012, abstract = {Visualization of data on structure and related temporal activity supports the analysis of correlations between the two types of data. This is typically done by linked views. This has shortcomings with respect to efficient space usage and makes mapping the effect of user input into one view into the other view difficult. We propose here a novel, space-efficient technique that `fuses' the two information spaces -- structure and activity -- in one view. We base our technique on the idea that user interaction should be simple, yet easy to understand and follow. We apply our technique, implemented in a prototype tool, for the understanding of software engineering datasets, namely static structure and execution traces of the Chromium web browser.}, address = {**Best Application-Paper**}, author = {Trümper, Jonas and Telea, Alexandru and Döllner, Jürgen}, booktitle = {Proceedings of the 10th Theory and Practice of Computer Graphics Conference}, month = 9, pages = {45-52}, publisher = {European Association for Computer Graphics}, title = {ViewFusion: Correlating Structure and Activity Views for Execution Traces}, year = 2012 }
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  Extending Recommendation Systems with Software Maps. Trümper, Jonas; Döllner, Jürgen (2012). 92-96.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TD2012, abstract = {In practice, recommendation systems have evolved as helpful tools to facilitate and optimize software engineering processes. Serving both developers and managers, specific recommendation systems address their individual problems. Yet, in a number of cases complementing them with other techniques can enhance their use and extend their scope. In this paper, we first discuss different perspectives on software-engineering processes and examples of recommendation systems that support representatives of these perspectives. We then identify how select software-map techniques can extend recommendation systems to facilitate decision making by addressing the perspectives' information and communication needs.}, author = {Trümper, Jonas and Döllner, Jürgen}, booktitle = {Proceedings of the 3rd International ICSE Workshop on Recommendation Systems for Software Engineering (RSSE)}, pages = {92-96}, publisher = {IEEE Computer Society}, title = {Extending Recommendation Systems with Software Maps}, year = 2012 }
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  Datenintegraton in dienstbasierte 3D-Geovisualisierungssysteme für mobile Geräte. Klimke, Jan; Döllner, Jürgen (2012). (Vol. 21) 266-275.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{noauthororeditor, author = {Klimke, Jan and Döllner, Jürgen}, booktitle = {Erdblicke – Perspektiven für die Geowissenschaften, 32. Jahrestagung in Potsdam}, month = {03}, pages = {266-275}, publisher = {Deutsche Gesellschaft für Photogrammetrie, Fernerkundung und Geoinformation (DGPF) e.V.}, title = {Datenintegraton in dienstbasierte 3D-Geovisualisierungssysteme für mobile Geräte}, volume = 21, year = 2012 }
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  Potentiale von massiven 3D Punktwolkendatenströmen. Richter, Rico; Döllner, Jürgen (2012). 215-222.
  [ BibTeX ] [ Details ]
   
  @inproceedings{RD12a, abstract = {Dieser Beitrag stellt eine Systemarchitektur zur effizienten Verwaltung, Aufbereitung, Analyse, und Visualisierung von 3D-Punktwolkendaten vor. Die zugrunde liegende Idee ist die, dass zukünftig durch eine große Zahl von Geräten kontinuierlich, aktuell und redundant die räumliche Umgebung in Form von 3D-Punktwolken erfasst werden kann, die dadurch entstehenden massiven 3D-Punktwolkendatenströme erzeugen ein diskretes, vierdimensionales Modell der räumlichen Umgebung. Zum Beispiel können dazu mobile Erfassungssysteme eingesetzt werden, die zukünftig einen festen Bestandteil der Ausstattung von Fahrzeugen darstellen. Wesentliche Herausforderungen liegen in der Integration von Einzeldatensätzen in den Gesamtdatenbestand, der interaktiven 3D-Visualisierung und der effizienten Analyse der Daten.}, author = {Richter, Rico and Döllner, Jürgen}, booktitle = {Geoinformatik 2012 - „Mobilität und Umwelt“}, month = 3, pages = {215-222}, publisher = {Shaker Verlag}, title = {Potentiale von massiven 3D Punktwolkendatenströmen}, year = 2012 }
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  A Visual Analysis Approach to Support Perfective Software Maintenance. Trümper, Jonas; Beck, Martin; Döllner, Jürgen (2012). 308-315.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TBD2012, abstract = {Ensuring code quality represents an essential task in «perfective software maintenance», which aims at keeping future maintenance costs low by facilitating adaptations of complex software systems. For this purpose, changes and related efforts have to be identified that imply high positive impact on future maintainability. In this paper, we propose a novel assessment method that applies visual analysis techniques to combine multiple indicators for low maintainability, including code complexity and entanglement with other parts of the system, and recent changes applied to the code. The approach generally helps to identify modules that impose a high risk by causing increased future maintenance efforts. Consequently, it allows for exploration, analysis, and planning of different preventive measures that, e.g., most likely will have a high return on investment. In our tool implementation, we use circular bundle views, extended by the third dimension in which indicators can be mapped to. We have evaluated our approach by conducting a case study based on our tool for a large-scale software system of an industry partner.}, author = {Trümper, Jonas and Beck, Martin and Döllner, Jürgen}, booktitle = {Proceedings of the 16th International Conference on Information Visualisation}, month = 7, pages = {308-315}, publisher = {IEEE Computer Society}, title = {A Visual Analysis Approach to Support Perfective Software Maintenance}, year = 2012 }
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  Service-oriented Visualization of Virtual 3D City Models. Klimke, Jan; Döllner, Jürgen in Directions Magazine (2012).
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{Klimke2012a, abstract = {Virtual 3D city models can effectively communicate complex 2D and 3D geospatial data. Myriad applications, from urban planning to solar potential of roof surfaces to noise pollution, can be modeled and visualized. However, massive amounts of data need to be processed. Authors Jan Klimke and Jürgen Döllner of the Hasso-Plattner-Institut, University of Potsdam, Germany detail a new, service-oriented approach that may solve some of the challenges of visualizing 3D data.}, author = {Klimke, Jan and Döllner, Jürgen}, howpublished = {Online Magazin Article}, journal = {Directions Magazine}, note = {http://www.directionsmag.com/articles/service-oriented-visualization-of-virtual-3d-city-models/226560}, title = {Service-oriented Visualization of Virtual 3D City Models}, year = 2012 }
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  Immersive Visualization of Virtual 3D City Models and its Applications in E-Planning. Engel, Juri; Döllner, Jürgen in International Journal of E-Planning Research (IJEPR) (2012). 1(4) 17-34.
  [ BibTeX ] [ Details ]
   
  @article{ED12_2, abstract = {Immersive visualization offers an intuitive access to and an effective way of realizing, exploring, and analyzing virtual 3D city models, which are essential tools for effective communication and management of complex urban spatial information in e-planning. In particular, immersive visualization allows for simulating planning scenarios and to receive a close-to-reality impression by both non-expert and expert stakeholders. This contribution is concerned with the main requirements and technical concepts of a system for visualizing virtual 3D city models in large-scale, fully immersive environments. It allows stakeholders ranging from citizens to decision-makers to explore and examine the virtual 3D city model and embedded planning models “in situ”. Fully immersive environments involve a number of specific requirements for both hardware and 3D rendering including enhanced 3D rendering techniques, an immersion-aware, autonomous, and assistive 3D camera system, and a synthetic, immersion-supporting soundscape. Based on these requirements, we have implemented a prototypical visualization system that we present in this article. The characteristics of fully immersive visualization enable a number of new applications within e-planning workflows and processes, in particular, with respect to public participation, decision support, and location marketing.}, author = {Engel, Juri and Döllner, Jürgen}, journal = {International Journal of E-Planning Research (IJEPR)}, number = 4, pages = {17-34}, publisher = {IGI Global}, title = {Immersive Visualization of Virtual 3D City Models and its Applications in E-Planning}, volume = 1, year = 2012 }
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  Semantische Klassifizierung von 3D-Punktwolken für Stadtgebiete. Richter, Rico; Döllner, Jürgen (2012). (1st ed) 127 - 134.
  [ BibTeX ] [ Details ]
   
  @inproceedings{RD12, abstract = {3D-Scanner-Technologien und bildbasierte Verfahren ermöglichen die flächen-deckende Erfassung von Städten und Metropolregionen in Form von georefe-renzierten 3D-Punktwolken. Diese Geobasisdaten stellen eine diskrete Oberflä-chenrepräsentation dar und verfügen über punktbezogene Metadaten, die bei der Erfassung generiert werden (z.B. Farbe, Intensität). Zentrale Herausforderungen für Systeme und Anwendungen, die mit diesen Daten arbeiten, sind das massive Datenaufkommen und die daraus resultierenden Verarbeitungszeiten. Die ziel-gerichtete und anwendungsspezifische Prozessierung von Teilmengen ist in der Regel nicht möglich, da die 3D-Punktwolken keine Informationen über zu Grunde liegenden Objektklassen (z.B. Bebauung, Vegetation, Gelände) beinhal-ten. In diesem Beitrag werden Konzepte und Techniken vorgestellt, die eine Klassifizierung von 3D-Punktwolken für ein Stadtgebiet ermöglichen. Durch die Anwendung von Out-of-Core Techniken können 3D Punktwolke mit mehreren Milliarden Punkten klassifiziert und in Objektklassen unterteilt werden. Analyse- und Visualisierungswerkzeuge können mit diesen zusätzlichen Informationen die benötigten Daten reduzieren, Verarbeitungszeiten verringern, Algorithmen optimieren sowie 3D Punktwolken selbst effektiver visualisieren.}, author = {Richter, Rico and Döllner, Jürgen}, booktitle = {Terrestrisches Laserscanning 2012 (TLS 2012)}, edition = 1, journal = {121. DVW-Seminar Terrestrisches-Laser-Scanning 2012}, pages = {127 - 134}, publisher = {Wißner-Verlag}, title = {Semantische Klassifizierung von 3D-Punktwolken für Stadtgebiete}, year = 2012 }
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  Server-Based Rendering of Large 3D Scenes for Mobile Devices Using G-Buffer Cube Maps. Döllner, Jürgen; Hagedorn, Benjamin; Klimke, Jan (2012). 97-100.
  [ BibTeX ] [ Details ]
   
  @inproceedings{DHK2012, abstract = {Large virtual 3D scenes play a major role in growing number of applications, systems, and technologies to effectively communicate complex spatial information. Their web-based provision, in particular on mobile devices, represents a key challenge for system and application development. In contrast to approaches based on streaming 3D scene data to clients, our approach splits 3D rendering into two processes: A server process is responsible for realtime rendering of virtual panoramas, represented by G-buffer cube maps, for a requested camera setting. The client reconstruction process uses these cube maps to reconstruct the 3D scene and allows users to operate on and interact with that representation. The key properties of this approach include that (a) the complexity of transmitted data not depend on the 3D scene’s complexity, (b) 3D rendering can take place within a controlled and a-priori known server environment, (c) crucial 3D model data never leaves the server environment, and (d) the clients can flexibly extend the 3D cube map viewer by adding both local 3D models and specialized 3D operations.}, author = {Döllner, Jürgen and Hagedorn, Benjamin and Klimke, Jan}, booktitle = {Web3D '12 Proceedings of the 17th International Conference on 3D Web Technology}, month = 8, pages = {97-100}, title = {Server-Based Rendering of Large 3D Scenes for Mobile Devices Using G-Buffer Cube Maps}, year = 2012 }
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  Towards Comprehensible Digital 3D Maps. Pasewaldt, Sebastian; Semmo, Amir; Trapp, Matthias; Döllner, Jürgen M. Jobst (red.) (2012). 261-276.
  [ BibTeX ] [ Details ]
   
  @inproceedings{Pasewaldt2012a, abstract = {Digital mapping services have become fundamental tools in economy and society to provide domain experts and non-experts with customized, multi-layered map contents. In particular because of the continuous advancements in the acquisition, provision, and visualization of virtual 3D city and landscape models, 3D mapping services, today, represent key components to a growing number of applications, like car navigation, education, or disaster management. However, current systems and applications providing digital 3D maps are faced by drawbacks and limitations, such as occlusion, visual clutter, or insufficient use of screen space, that impact an effective comprehension of geoinformation. To this end, cartographers and computer graphics engineers developed design guidelines, rendering and visualization techniques that aim to increase the effectiveness and expressiveness of digital 3D maps, but whose seamless combination has yet to be achieved. This work discusses potentials of digital 3D maps that are based on combining cartography-oriented rendering techniques and multi-perspective views. For this purpose, a classification of cartographic design principles, visualization techniques, as well as suitable combinations are identified that aid comprehension of digital 3D maps. According to this classification, a prototypical implementation demonstrates the benefits of multi-perspective and non-photorealistic rendering techniques for visualization of 3D map contents. In particular, it enables (1) a seamless combination of cartography-oriented and photorealistic graphic styles while (2) increasing screen-space utilization, and (3) simultaneously directing a viewer’s gaze to important or prioritized information.}, author = {Pasewaldt, Sebastian and Semmo, Amir and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Service-Oriented Mapping 2012 (SOMAP2012)}, chapter = 4, editor = {Jobst, Markus}, month = 11, organization = {Internation Cartographic Association}, pages = {261-276}, publisher = {Jobstmedia Management Verlag, Wien}, title = {Towards Comprehensible Digital 3D Maps}, year = 2012 }
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  Single-Pass Rendering of Day and Night Sky Phenomena. Limberger, Daniel; Engel, Juri; Döllner, Jürgen (2012). 55-62.
  [ BibTeX ] [ Details ]
   
  @inproceedings{MED12, abstract = {This paper presents astronomical based rendering of skies as seen from low altitudes on earth, in respect to location, date, and time. The technique allows to compose an atmosphere with sun, multiple cloud layers, moon, bright stars, and Milky Way, into a holistic sky with unprecedented high level of detail and diversity. GPU generated, viewpoint-aligned billboards are used to render stars with approximated color, brightness, and scintillations. A similar approach is used to synthesize the moon considering lunar phase, earthshine, shading, and lunar eclipses. Atmosphere and clouds are rendered using existing methods adapted to our needs. Rendering is done in a single pass supporting interactive day-night cycles with low performance impact, and allows for easy integration in existing rendering systems. Results of our approach are compared to related renderings and photos, and the performance impact is discussed.}, author = {Limberger, Daniel and Engel, Juri and Döllner, Jürgen}, booktitle = {Proceedings of the Vision, Modeling, and Visualization Workshop 2012}, month = 11, pages = {55-62}, publisher = {Eurographics Association}, title = {Single-Pass Rendering of Day and Night Sky Phenomena}, year = 2012 }
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  Immersive Visualisierung von virtuellen 3D-Stadtmodellen und ihr Einsatz in der Stadtplanung. Engel, Juri; Döllner, Jürgen (2012). (Vol. 21) 165-172.
  [ BibTeX ] [ Details ]
   
  @inproceedings{ED12, abstract = {Virtuelle 3D-Stadtmodelle ermöglichen die effektive Kommunikation komplexer stadträumlicher Informationen. Immersive Visualisierung von virtuellen 3D-Stadtmodellen bietet einen intuitiven Zugang zu diesen Informationen und eröffnet neue Anwendungsfelder in der Stadtplanung, z. B. bei der Entscheidungsfindung, dem Marketing und der Öffentlichkeitspräsentation von Projekten, Vorgängen oder Konzepten. Immersive Visualisierung impliziert zahlreiche Anforderungen an das Softwaresystem. In diesem Beitrag untersuchen wir die softwaretechnischen Herausforderungen bei der Entwicklung eines solchen Systems und zeigen anhand eines Prototyps zur immersiven Visualisierung von virtuellen 3D-Stadtmodellen wie man diese Herausforderungen bewältigen kann.}, author = {Engel, Juri and Döllner, Jürgen}, booktitle = {Publikationen der Deutschen Gesellschaft für Photogrammetrie, Fernerkundung und Geoinformation}, pages = {165-172}, publisher = {DGPF}, title = {Immersive Visualisierung von virtuellen 3D-Stadtmodellen und ihr Einsatz in der Stadtplanung}, volume = 21, year = 2012 }
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  Colonia 3D - Communication of Virtual 3D Reconstructions in Public Spaces. Trapp, Matthias; Semmo, Amir; Pokorski, Rafael; Herrmann, Claus-Daniel; Döllner, Jürgen; Eichhorn, Michael; Heinzelmann, Michael in International Journal of Heritage in the Digital Era (IJHDE), (M. Ioannides, red.) (2012). 1(1) 45-74.
  [ BibTeX ] [ Details ]
   
  @article{TSPHDEH12, abstract = {The communication of cultural heritage in public spaces such as museums or exhibitions, gain more and more importance during the last years. The possibilities of interactive 3D applications open a new degree of freedom beyond the mere presentation of static visualizations, such as pre-produced video or image data. A user is now able to directly interact with 3D virtual environments that enable the depiction and exploration of digital cultural heritage artifacts in real-time. However, such technology requires concepts and strategies for guiding a user throughout these scenarios, since varying levels of experiences within interactive media can be assumed. This paper presents a concept as well as implementation for communication of digital cultural heritage in public spaces, by example of the project Roman Cologne. It describes the results achieved by an interdisciplinary team of archaeologists, designers, and computer graphics engineers with the aim to virtually reconstruct an interactive high-detail 3D city model of Roman Cologne.}, author = {Trapp, Matthias and Semmo, Amir and Pokorski, Rafael and Herrmann, Claus-Daniel and Döllner, Jürgen and Eichhorn, Michael and Heinzelmann, Michael}, editor = {Ioannides, Marinos}, journal = {International Journal of Heritage in the Digital Era (IJHDE)}, month = 1, note = {Cover Image}, number = 1, pages = {45-74}, publisher = {Multi-Science Publishing}, title = {Colonia 3D - Communication of Virtual 3D Reconstructions in Public Spaces}, volume = 1, year = 2012 }
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  Maintenance of Embedded Systems: Supporting Program Comprehension Using Dynamic Analysis. Trümper, Jonas; Voigt, Stefan; Döllner, Jürgen (2012). 58-64.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TVD2012, abstract = {Maintenance of embedded software systems is faced with multiple challenges, including the exploration and analysis of the actual system's runtime behavior. As a fundamental technique, tracing can be used to capture data about runtime behavior as a whole, and represents one of the few methods to observe and record data about embedded systems within their production environments. In this paper we present a software-based, function-boundary tracing approach for embedded software systems. It uses static binary instrumentation, which implies only lightweight memory and performance overheads. To further reduce these overheads, instrumentation can be configured per trace, i.e., activated only for a specified group of functions without having to recompile the system. The technique can be characterized by its robust implementation and its versatile usage. It is complemented by a visualization framework that allows for analysis and exploration of a system's runtime behavior, e.g., to examine thread interaction. To show the technique's applicability, we conclude with a case study that has been applied to an industrial embedded software system.}, author = {Trümper, Jonas and Voigt, Stefan and Döllner, Jürgen}, booktitle = {In Proceedings of the 2nd International ICSE Workshop on Software Engineering for Embedded Systems (SEES)}, pages = {58-64}, publisher = {IEEE Computer Society}, title = {Maintenance of Embedded Systems: Supporting Program Comprehension Using Dynamic Analysis}, year = 2012 }
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  Challenges and Approaches for the Visualization of Movement Trajectories in 3D Geovirtual Environments Buschmann, Stefan; Trapp, Matthias; Döllner, Jürgen (2012).
  [ BibTeX ] [ Details ]
   
  @proceedings{Buschmann2012a, abstract = {The visualization of trajectories and their attributes represents an essential functionality for spatio-temporal data visualization and analysis. Many visualization methods, however, focus mainly on sparse 2D movements or consider only the 2D components of movements. This paper is concerned with true 3D movement data, i.e., movements that take place in the three-dimensional space and which characteristics significantly depend an all dimensions. In this case, spatio-temporal visualization approaches need to map all three spatial dimensions together with required mappings for associated attributes. We describe visualization approaches for true 3D movement data and evaluate their application within 3D geovirtual environments. We also identify challenges and propose approaches for the interactive visualization of 3D movement data using 3D geovirtual environments as scenery.}, author = {Buschmann, Stefan and Trapp, Matthias and Döllner, Jürgen}, booktitle = {GIScience workshop on GeoVisual Analytics, Time to Focus on Time}, title = {Challenges and Approaches for the Visualization of Movement Trajectories in 3D Geovirtual Environments}, year = 2012 }
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  GPU-Based Visualization of Hybrid Terrain Models. Paredes, E.G.; Boo, M.; Amor, M.; Döllner, J.; Bruguera, J.D. (2012).
  [ BibTeX ] [ Details ]
   
  @inproceedings{PBADB12, abstract = {Hybrid terrain models formed by a large regular mesh refined with detailed local TIN meshes represent an interesting and efficient approach for the representation of complex terrains. However, direct rendering of the component meshes would lead to overlapping geometries and discontinuities around their boundaries. The Hybrid Meshing algorithm solves this problem by generating an adaptive tessellation between the boundaries of the component meshes in real-time. In this paper, we present a highly parallel implementation of this algorithm using the Geometry Shader on the GPU.}, author = {Paredes, E.G. and Boo, M. and Amor, M. and Döllner, J. and Bruguera, J.D.}, booktitle = {International Conference on Computer Graphics Theory and Applications (GRAPP)}, title = {GPU-Based Visualization of Hybrid Terrain Models}, year = 2012 }

2011 [ nach oben ]

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  Artistic Stylization of Images and Video. Collomosse, John; Kyprianidis, Jan Eric (2011).
  [ BibTeX ] [ Details ]
   
  @inproceedings{CK11, abstract = {The half-day tutorial provides an introduction to Non-Photorealistic Rendering (NPR), targeted at both students and experienced researchers of Computer Graphics who have not previously explored NPR in their work. The tutorial focuses on two-dimensional (2D) NPR, specifically the transformation of photos or videos into synthetic artwork (e.g. paintings or cartoons). Consequently the course will touch not only on computer graphics topics, but also on the image processing and computer vision techniques that drive such algorithms. However the latter concepts will be introduced gently and no prior knowledge is assumed beyond a working knowledge of filtering and convolution operations. Some elements of the course will touch upon GPU implementation, but GPU concepts will be described at a high level of abstraction without need for detailed working knowledge of GPU programming.}, author = {Collomosse, John and Kyprianidis, Jan Eric}, booktitle = {Tutorial at Eurographics}, title = {Artistic Stylization of Images and Video}, year = 2011 }
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  Ein Ansatz für die Differenzanalyse zwischen 3D-Punktwolken und 3D-Referenzgeometrie. Richter, Rico; Döllner, Jürgen (2011). 463 - 471.
  [ BibTeX ] [ Details ]
   
  @inproceedings{RD11a, abstract = {Dieser Beitrag stellt ein Verfahren zur Detektion, Visualisierung und Analyse von Differenzen zwischen massiven 3D-Punktwolken und explizit spezifizierten 3D-Referenz-Geometrien vor. Das Verfahren basiert darauf 3D-Punktwolkendaten mit Abstandsinformationen zu attributieren. Die Berechnung dieser Abstandsinformationen wird in einem Vorverarbeitungsschritt durchgeführt und kann auf beliebig große 3D-Punktwolken angewendet werden. Für die Visualisierung der Ergebnisse wird eine echtzeitfähige, punktbasierte 3D-Rendering-Technik verwendet. Mit diesem Verfahren können insbesondere interaktive 3D-Explorations- und Analysewerkzeuge entwickelt werden, die z. B. Aussagen über Veränderungen von Gebäuden, Bauwerken und Infrastruktureinrichtungen bzw. die Abweichungen zwischen Planungsmodell und Ist-Zustand sichtbar werden lassen.}, author = {Richter, Rico and Döllner, Jürgen}, booktitle = {31. Wissenschaftlich-Technische Jahrestagung der DGPF}, journal = {31. Wissenschaftlich-Technische Jahrestagung der DGPF}, month = 4, pages = {463 - 471}, title = {Ein Ansatz für die Differenzanalyse zwischen 3D-Punktwolken und 3D-Referenzgeometrie}, year = 2011 }
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  Service-oriented interactive 3D visualization of massive 3D city models on thin clients. Hildebrandt, Dieter; Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen (2011). 1--1.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Hildebrandt2011, address = {New York, New York, USA}, author = {Hildebrandt, Dieter and Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications - COM.Geo '11}, pages = {1--1}, publisher = {ACM Press}, title = {Service-oriented interactive 3D visualization of massive 3D city models on thin clients}, year = 2011 }
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  Image-based strategies for interactive visualisation of complex 3D geovirtual environments on lightweight devices. Hildebrandt, Dieter; Hagedorn, Benjamin; Döllner, Jürgen in Journal of Location Based Services (2011). 5(2) 100-120.
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{doi:10.1080/17489725.2011.580787, abstract = {In this article, we present strategies for service-oriented, standards and image-based 3D geovisualisation that have the potential to provide interactive visualisation of complex 3D geovirtual environments (3DGeoVE) on lightweight devices. In our approach, interactive geovisualisation clients retrieve sets of 2D images of projective views of 3DGeoVEs generated by a 3D rendering service. As the key advantage of the image-based approach, the complexity that a client is exposed for displaying a visual representation is reduced to a constant factor primarily depending on the image resolution. To provide users with a high degree of interactivity, we propose strategies that are based on additional service-side functionality and on exploiting multiple layers of information encoded into the images for the local reconstruction of visual representations of the remote 3DGeoVE. The use of service-orientation and standards facilitates designing distributed 3D geovisualisation systems that are open, interoperable and can easily be adapted to changing requirements. We demonstrate the validity of the proposed strategies by presenting proof-of-concept implementations of several image-based 3D clients for the case of virtual 3D city models.}, author = {Hildebrandt, Dieter and Hagedorn, Benjamin and Döllner, Jürgen}, journal = {Journal of Location Based Services}, number = 2, pages = {100-120}, title = {Image-based strategies for interactive visualisation of complex 3D geovirtual environments on lightweight devices}, volume = 5, year = 2011 }
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  Service-Oriented Interactive 3D Visualization of Massive 3D City Models on Thin Clients. Hildebrandt, Dieter; Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen in 2nd Int. Conference on Computing for Geospatial Research & Application COM.Geo 2011 (2011).
  [ BibTeX ] [ URL ] [ Details ]
   
  @article{HKHD11, abstract = {Virtual 3D city models serve as integration platforms for complex geospatial and georeferenced information and as medium for effctive communication of spatial information. In this paper, we present a system architecture for service-oriented, interactive 3D visualization of massive 3D city models on thin clients such as mobile phones and tablets. It is based on high performance, server-side 3D rendering of extended cube maps, which are interactively visualized by corresponding 3D thin clients. As key property, the complexity of the cube map data transmitted between server and client does not depend on the model's complexity. In addition, the system allows the integration of thematic raster and vector geodata into the visualization process. Users have extensive control over the contents and styling of the visual representations. The approach provides a solution for safely, robustly distributing and interactively presenting massive 3D city models. A case study related to city marketing based on our prototype implementation shows the potentials of both server-side 3D rendering and fully interactive 3D thin clients on mobile phones.}, author = {Hildebrandt, Dieter and Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {COM.Geo '11 Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications}, journal = {2nd Int. Conference on Computing for Geospatial Research & Application COM.Geo 2011}, month = 5, title = {Service-Oriented Interactive 3D Visualization of Massive 3D City Models on Thin Clients}, year = 2011 }
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  Towards Service-Oriented, Standards- and Image-Based Styling of 3D Geovirtual Environments. Hildebrandt, Dieter in Proceedings of the 5th Ph.D. Retreat of the HPI Research School on Service-oriented Systems Engineering, C. Meinel, Plattner, H., Döllner, J., Weske, M., Polze, A., Hirschfeld, R., Naumann, F., Giese, H. (reds.) (2011). (Vol. 46) 133-147.
  [ BibTeX ] [ URL ] [ Details ]
   
  @incollection{hildebrandt2011towards, abstract = {The server-side, service-oriented rendering of massive 3D geovirtual environments (3DGeoVEs) has the potential to enable users with lightweight clients to access high quality, image-based visual representations of the environments without having to download massive amounts of geodata. Image post-processing (IPP) is a well-known concept that allows for decoupling the process of generating an image from applying enhancement processes to already generated images. Moreover, several visual effects are implemented most efficiently and effectively as image post-processes. However, so far no proposals exist for providing image post-processing of 2D images of projective views of visual representations of 3DGeoVE in a SOA and based on standards. In this paper, we investigate how IPP functionality and the functionality of styling of visual representations of 3DGeoVE based on IPP can be provided in a SOA based on standards. First, we introduce the concepts of IPP and styling. Then, we present an analysis of different characteristics of styling and IPP and design dimensions relevant when building a system for styling and IPP. From the analysis, we derive a set of requirements for a concept and system providing IPP and styling functionality based on IPP. We present a preliminary concept for a system meeting the identified requirements and report on initial implementation and evaluation results.}, author = {Hildebrandt, Dieter}, booktitle = {Proceedings of the 5th Ph.D. Retreat of the HPI Research School on Service-oriented Systems Engineering}, editor = {Meinel, Christoph and Plattner, Hasso and Döllner, Jürgen and Weske, Mathias and Polze, Andreas and Hirschfeld, Robert and Naumann, Felix and Giese, Holger}, pages = {133-147}, publisher = {Universitätsverlag Potsdam}, series = {Technische Berichte des Hasso-Plattner-Instituts für Softwaresystemtechnik an der Universität Potsdam}, title = {Towards Service-Oriented, Standards- and Image-Based Styling of 3D Geovirtual Environments}, volume = 46, year = 2011 }
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  Integrating 3D Data in Service-based Visualization Systems. Klimke, Jan; Hildebrandt, Dieter; Hagedorn, Benjamin; Döllner, Jürgen (2011).
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2011b, abstract = {Georeferenced data is available from a wide range of sources, e.g., Directory Services, Sensor Observation Services, Web Feature Services or even proprietary interfaces. Many of the data originating from an Internet of things will be threedimensional representing outdoor as well as indoor geographic features and their properties. Based on this data, its integration, and its visualization totally new applications and systems could be designed and implemented supporting various applications domains. Recent work in the area of service-based 3D visualization enables high-quality visualization of complex 3D geodata, e.g., 3D city models and 3D indoor building models, on thin clients as well as mobile devices such as smartphones and tablets. This work uses a service-based, image-based visualization approach that decouples the server-side resource-intensive management and rendering of complex, massive 3D geodata from client-side display functionalities: A Web View Service provides image representations of a 3D scene, these images, which can contain different types of information per pixel, are transmitted to a client application that can reconstruct a 3D representation of this scene. – In this talk, we will describe how to combine 3D geodata originating from the Internet of Things with this service-based approach in a way that allows for the interactive exploration of and interaction with 3D worlds and objects of interest. In detail, this 3D geodata can be integrated into the visualization process a) at the rendering stage of a portrayal service, b) through an image post processing step or c) in the client application itself. Moreover, this data can be visually represented directly by modifying the appearance of existing features, e.g., for visualizing measurements, or indirectly by introducing additional objects, e.g., icons, into the 3D scene. We will discuss advantages and disadvantages of these different approaches for implementing visualization applications using live geodata sources.}, author = {Klimke, Jan and Hildebrandt, Dieter and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {COM.Geo '11 Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications}, publisher = {ACM}, title = {Integrating 3D Data in Service-based Visualization Systems}, year = 2011 }
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  Integrating 3D data in service-based visualization systems. Klimke, Jan; Hildebrandt, Dieter; Hagedorn, Benjamin; Döllner, Jürgen (2011). 1.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Klimke2011, address = {New York, New York, USA}, author = {Klimke, Jan and Hildebrandt, Dieter and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications - COM.Geo '11}, pages = 1, publisher = {ACM Press}, title = {Integrating 3D data in service-based visualization systems}, year = 2011 }
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  Image-Based Strategies for Interactive Visualization of Complex 3D Geovirtual Environments on Lightweight Devices. Hildebrandt, Dieter; Hagedorn, Benjamin; Döllner, in Journal of Location Based Services (JLBS) (2011). 5(2) 100--120.
  [ BibTeX ] [ Details ]
   
  @article{HHD11, abstract = {In this article, we present strategies for service-oriented, standards and image-based 3D geovisualisation that have the potential to provide interactive visualisation of complex 3D geovirtual environments (3DGeoVE) on lightweight devices. In our approach, interactive geovisualisation clients retrieve sets of 2D images of projective views of 3DGeoVEs generated by a 3D rendering service. As the key advantage of the image-based approach, the complexity that a client is exposed for displaying a visual representation is reduced to a constant factor primarily depending on the image resolution. To provide users with a high degree of interactivity, we propose strategies that are based on additional service-side functionality and on exploiting multiple layers of information encoded into the images for the local reconstruction of visual representations of the remote 3DGeoVE. The use of service-orientation and standards facilitates designing distributed 3D geovisualisation systems that are open, interoperable and can easily be adapted to changing requirements. We demonstrate the validity of the proposed strategies by presenting proof-of-concept implementations of several image-based 3D clients for the case of virtual 3D city models.}, address = {Bristol, PA, USA}, author = {Hildebrandt, Dieter and Hagedorn, Benjamin and Döllner}, journal = {Journal of Location Based Services (JLBS)}, month = 6, number = 2, pages = {100--120}, publisher = {Taylor & Francis, Inc.}, title = {Image-Based Strategies for Interactive Visualization of Complex 3D Geovirtual Environments on Lightweight Devices}, volume = 5, year = 2011 }
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  Image and Video Abstraction by Multi-scale Anisotropic Kuwahara Filtering. Kyprianidis,; Eric, Jan (2011).
  [ BibTeX ] [ Details ]
   
  @inproceedings{Kyp11, abstract = {The anisotropic Kuwahara filter is an edge-preserving filter that is especially useful for creating stylized abstractions from images or videos. It is based on a generalization of the Kuwahara filter that is adapted to the local structure of image features. In this work, two limitations of the anisotropic Kuwahara filter are addressed. First, it is shown that by adding thresholding to the weighting term computation of the sectors, artifacts are avoided and smooth results in noise-corrupted regions are achieved. Second, a multi-scale computation scheme is proposed that simultaneously propagates local orientation estimates and filtering results up a low-pass filtered pyramid. This allows for a strong abstraction effect and avoids artifacts in large low-contrast regions. The propagation is controlled by the local variances and anisotropies that are derived during the computation without extra overhead, resulting in a highly efficient scheme that is particularly suitable for real-time processing on a GPU.}, author = {Kyprianidis and Eric, Jan}, booktitle = {Proc. 9th Symposium on Non-Photorealistic Animation and Rendering (NPAR)}, title = {Image and Video Abstraction by Multi-scale Anisotropic Kuwahara Filtering}, year = 2011 }
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  Ansätze zur kartographischen Gestaltung von 3D-Stadtmodellen. Semmo, Amir; Trapp, Matthias; Döllner, Jürgen in Publikationen der Deutschen Gesellschaft für Photogrammetrie, Fernerkundung und Geoinformation e.V. (2011). (Vol. 20) 473-482.
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  @inproceedings{STD11, abstract = {Interaktive virtuelle 3D-Stadtmodelle haben sich zu einem bewährten Medium für die effektive und effiziente Kommunikation von Geoinformation entwickelt. Sie präsentieren eine spezialisierte Form geovirtueller Umgebungen und sind gekennzeichnet durch ein zugrunde liegendes 3D-Geländemodell, einer darin befindlichen 3D-Bebauung sowie des dazu komplementären Straßen-, Grünflächen- und Naturraumes. 3D-Stadtmodell-Systeme ermöglichen es dem Nutzer, sich im Modell interaktiv zu bewegen und sie stellen die Grundfunktionen für die Exploration, Analyse, Präsentation und das Editieren der raumbezogenen Information bereit. Besonders im Gebiet der kartenähnlichen und kartenverwandten 3D-Darstellungen stellen u.a. automatische Verfahren und Techniken zur Stilisierung und Abstraktion von Objekten eines 3D Stadtmodell ein Hauptproblem für die interaktive 3D-Bildsynthese dar. Hier spielt insbesondere die Abstraktion und Illustration potentiell wichtiger Information und somit die Reduzierung der kognitiven Belastung des Nutzers eine tragende Rolle. Diesbezüglich sind Verfahren und Techniken zur nicht-photorealistischen Bildsynthese ein bewährtes Mittel der Computergrafik, deren direkte Anwendung auf ein komplettes 3D-Stadtmodell jedoch häufig monotone sowie gestalterisch und kartographisch stark eingeschränkte Resultate liefert. Eine effiziente und kontextsensitive Kommunikation von 3D-Geoinformation bedarf jedoch der Kopplung von Objektsemantik und Abstraktionsverfahren. Diese Arbeit präsentiert ein Konzept und dessen Umsetzung, das die Auswahl und Parametrisierung von nicht-photorealistischen Darstellungstechniken auf Basis von Objektsemantiken erlaubt (Abbildung 1). Dies ermöglicht die Zuweisung unterschiedlicher automatischer Abstraktionstechniken zu Objekten und Objektgruppen. Der vorgestellte Ansatz ist echtzeitfähig und erlaubt eine interaktive Klassifikation von Objekten und Features zur Laufzeit, wodurch sich u.a. Szenarien zur interaktiven Exploration von thematisch-stilisierten Features bzw. feature-bezogenen Daten visualisieren lassen. Dieser Ansatz eröffnet Möglichkeiten für eine gezielte und systematische kartographische Gestaltung von 3D-Stadtmodellen sowie deren echtzeitfähige Implementierung durch entsprechende 3D-Visualisierungsdienste.}, author = {Semmo, Amir and Trapp, Matthias and Döllner, Jürgen}, booktitle = {31. Wissenschaftlich-Technische Jahrestagung der DGPF}, journal = {31. Wissenschaftlich-Technische Jahrestagung der DGPF}, month = 4, pages = {473-482}, publisher = {Landesvermessung und Geobasisinformation Brandenburg}, series = {Publikationen der Deutschen Gesellschaft für Photogrammetrie, Fernerkundung und Geoinformation e.V.}, title = {Ansätze zur kartographischen Gestaltung von 3D-Stadtmodellen}, volume = 20, year = 2011 }
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  Image and Video Abstraction by Coherence-Enhancing Filtering. Kyprianidis, Jan Eric; Kang, Henry in Computer Graphics Forum (2011). 30(2) 593--602.
  [ BibTeX ] [ Details ]
   
  @article{KK11, abstract = {In this work, we present a non-photorealistic rendering technique to create stylized abstractions from color images and videos. Our approach is based on adaptive line integral convolution in combination with directional shock filtering. The smoothing process regularizes directional image features while the shock filter provides a sharpening effect. Both operations are guided by a flow field derived from the structure tensor. To obtain a high-quality flow field, we present a novel smoothing scheme for the structure tensor based on Poisson's equation. Our approach effectively regularizes anisotropic image regions while preserving the overall image structure and achieving a consistent level of abstraction. Moreover, it is suitable for per-frame filtering of video and can be efficiently implemented to process content in real-time.}, author = {Kyprianidis, Jan Eric and Kang, Henry}, journal = {Computer Graphics Forum}, note = {Proceedings Eurographics 2011}, number = 2, pages = {593--602}, title = {Image and Video Abstraction by Coherence-Enhancing Filtering}, volume = 30, year = 2011 }
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  DigiPolis - An Approach for Interactive 3D Building & Interior Models as Communication Tools. Quantz, Joachim; Döllner, Jürgen; Fricke, Rolf; Tolksdorf, Robert; Hoppe, Thomas; Jung, Ingolf in Kultur und Informatik, J. Sieck (red.) (2011).
  [ BibTeX ] [ Details ]
   
  @inproceedings{QDFTHJ11, abstract = {This paper gives an overview over the research project DigiPolis, which develops a framework integrating 3D models of buildings, including interior models, with semantic annotations and intuitive, touch-based interaction and navigation. Results obtained in the first year of the project range from touch-based interaction in 3D building and interior models over ontology browser to interactive 3D annotations. The current DigiPolis showcase comprises a 3D model of the Berlin Hauptbahnhof, Berlin’s central station, embedded in a generic virtual 3D Berlin model and Open Street Map. Application areas for DigiPolis technology include visitor information, controlling & monitoring, event management and facility management as well as all IT solutions that require a sophisticated, interactive 3D front end for complex, detailed 3D geospatial and related georeferenced information.}, author = {Quantz, Joachim and Döllner, Jürgen and Fricke, Rolf and Tolksdorf, Robert and Hoppe, Thomas and Jung, Ingolf}, booktitle = {Multimediale Systeme}, editor = {Sieck, Jürgen}, month = 5, publisher = {Verlag Werner Hülsbusch}, series = {Kultur und Informatik}, title = {DigiPolis - An Approach for Interactive 3D Building & Interior Models as Communication Tools}, year = 2011 }
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  Interactive Areal Annotations for 3D Treemaps of Large-Scale Software Systems. Lehmann, Christine; Trümper, Jonas; Döllner, Jürgen (2011).
  [ BibTeX ] [ Details ]
   
  @inproceedings{LTD2011, abstract = {Exploration of large-scale software systems typically poses a challenge to human mind and perception. Among other approaches to this challenge, visualizing such tree-structured data using treemaps is a common solution. Especially three-dimensional treemaps enable intuitive exploration through a large-scale software system using the landscape metaphor for navigation. Annotations of treemap nodes contribute essential semantic information, e.g., class or method names. However, textual annotations in three-dimensional environments typically suffer from ambiguousness, illegibility and instability. In this paper, we propose an interactive labeling algorithm suitable for 3D areal annotation of large-scale software systems that are visualized using three-dimensional treemaps. We demonstrate how the algorithm generates an unambiguous and stable layout with respect to legibility using 3D treemaps of a software visualization tool that visualizes the hierarchical structure of a large software system, e.g., Google Chromium.}, author = {Lehmann, Christine and Trümper, Jonas and Döllner, Jürgen}, booktitle = {Proceedings (CD-ROM) of the Workshop on Geovisualization}, title = {Interactive Areal Annotations for 3D Treemaps of Large-Scale Software Systems}, year = 2011 }
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  Colonia3D. Trapp, Matthias; Semmo, Amir; Döllner, Jürgen (2011). 201-212.
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  @inproceedings{TSD11, abstract = {Dieser Beitrag stellt die Ergebnisse des interdisziplinären Projektes Colonia3D - Visualisierung des Römischen Kölns vor. Die digitale 3D Rekonstruktion des antiken Köln ist das Ergebnis eines gemeinsamen Forschungsprojekts des Archäologischen Instituts der Universität zu Köln, der Köln International School of Design (KISD) der Fachhochschule Köln, des Hasso-Plattner Instituts an der Universität Potsdam und des Römisch Germanischen Museums (RGM) Köln. Der Beitrag präsentiert die wesentlichen Konzepte dieses interaktiven, auf Museen ausgerichteten 3D-Informationssystems, beschreibt verschiedene Präsentationsmodi und deren technische Umsetzung. Er diskutiert Vorgehensweisen und Interaktionskonzepte, die den Benutzer während der Erkundung und Bewegung im virtuellen 3D-Stadtmodell unterstützen. Weiter werden die Techniken für den Austausch, die Aufbereitung und die Optimierung komplexer 3D-Datensätze beschrieben sowie Potenziale für digitale Museen und Ausstellungen skizziert. Der vorgestellte Ansatz stellt insbesondere eine IT-Lösung für einen vereinfachten, räumlich-kontextintegrierten informellen Wissenszugang zu archäologischer Fachinformation dar.}, author = {Trapp, Matthias and Semmo, Amir and Döllner, Jürgen}, booktitle = {Tagungsband der 9. Konferenz Kultur und Informatik - Multimediale Systeme}, journal = {Tagungsband der 9. Konferenz Kultur und Informatik - Multimediale Systeme}, month = 5, pages = {201-212}, publisher = {Werner Hülsbusch Verlag}, title = {Colonia3D}, year = 2011 }
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  Visualization of Execution Traces and its Application to Software Maintenance. Technical Report (PhD dissertation), Bohnet, Johannes (2011).
  [ BibTeX ] [ Details ]
   
  @phdthesis{BOH11, abstract = {Maintaining complex software systems tends to be costly because developers spend a significant part of their time with trying to understand the system’s structure and behavior. Among many reasons, program understanding is time consuming because the system’s structure and its internal behavior are not intuitively realizable and can only be partially inspected. The visualization of execution traces represents an approach to help developers to understand complex systems. Practically, execution trace visualization captures the sequence of function calls over time during system execution, analyzes and abstracts that data, and derives visual representations that permit developers to analyze the system’s structure and behavior. The goal of this thesis is to develop a trace visualization concept and tool that can handle the computational and cognitive scalability issues that trace visualization encounters due to the large amount of data that is typically produced when logging runtime processes. The thesis’ concept includes the following building blocks: (1) A concept for generating traces of C/C++ software systems in a scalable way, (2) a concept for trace reduction that automatically identifies recursive boundaries within the trace and, by this, supports developers in exploring a trace using a top-down approach, (3) a framework for trace visualization techniques that provides solutions to the question as to how core techniques for viewing trace data can be implemented such that developers are supported in performing top-down and bottom-up comprehension strategies, and (4) a concept for combining trace visualization with 3rd party tools and systems for reverse engineering. As a further contribution, this thesis validates the proposed concept by means of an implementation, performance measurements, and case studies. The implementation of the concept is provided as a framework for creating trace visualization tools. To ensure scalability of the concept, performance measurements were taken while applying the tool to large C/C++ software systems. Furthermore, the concept and tool has been experimentally applied to industrially developed software systems to solve particular maintenance problems in real-world scenarios.}, author = {Bohnet, Johannes}, school = {Hasso-Plattner-Institut, University of Potsdam}, title = {Visualization of Execution Traces and its Application to Software Maintenance}, year = 2011 }
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  Integrierte Echtzeit-Visualisierung von massiven 3D-Punktwolken und georeferenzierten Texturdaten. Richter, Rico; Döllner, Jürgen in Photogrammetrie Fernerkundung Geoinformation (PFG) (2011). 2011(3) 145-154.
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  @article{RD11b, abstract = {Dieser Beitrag stellt ein Verfahren vor, das die integrierte Echtzeit-Visualisierung von massiven 3D-Punktwolkendaten zusammen mit georeferenzierten Texturdaten ermöglicht. Beides sind wesentliche Kategorien von Geodaten, die insbesondere aufgrund ihrer wach-senden Verfügbarkeit und sinkender Kosten, generiert mit flugzeuggestützten oder mobilen Scan-Systemen, zunehmend Einsatz finden. Die Massivität der entstehenden Daten stellt eine Herausforde-rung sowohl für die Algorithmik wie auch für die Hardware-Ressourcen dar. Um die Daten effizient verarbeiten und in Echtzeit visualisieren zu können, werden sog. Out-of-Core-Algorithmen und Le-vel-of-Detail-Strukturen benötigt. Das vorgestellte Out-of-Core- und LOD-Konzept für unbeschränkt große 3D-Punktwolkendaten ermöglicht deren Echtzeit-Visualisierung zusammen mit georeferenzier-ten Texturdaten, z. B. digitalen Luftbildern. Dieser Ansatz erlaubt es, 3D-Punktwolkendaten in der Visualisierung mit beliebigen georeferenzierten thematischen Information zu attributieren, sodass z. B. Objekte und Bereiche nicht nur geometrisch, sondern auch thematisch präsentiert, exploriert und analysiert werden können. In einem Vorverarbeitungsschritt werden dazu die Daten aufbereitet und in eine räumliche LOD-Struktur überführt, auf der die echtzeitfähige, punktbasierte 3D-Rendering-Technik operiert. Mit dem Ansatz wird es möglich, interaktive 3D-Analyse-Werkzeuge und Simulati-onsverfahren zu realisieren, die direkt und effizient auf 3D-Punktwolkenrohdaten zugreifen.}, author = {Richter, Rico and Döllner, Jürgen}, journal = {Photogrammetrie Fernerkundung Geoinformation (PFG)}, number = 3, pages = {145-154}, title = {Integrierte Echtzeit-Visualisierung von massiven 3D-Punktwolken und georeferenzierten Texturdaten}, volume = 2011, year = 2011 }
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  Concepts for Automatic Generalization of Virtual 3D Landscape Models. Glander, Tassilo; Trapp, Matthias; Döllner, Jürgen E. Buhmann, Ervin, S., Tomlin, D., Pietsch, M. (reds.) (2011). 127-135.
  [ BibTeX ] [ Details ]
   
  @inproceedings{GTD11, abstract = {This paper discusses concepts for the automatic generalization of virtual 3D landscape models. As complexity, heterogeneity, and diversity of geodata that constitute landscape models are constantly growing, the need for landscape models that generalize their contents to a consistent, coherent level-of-abstraction and information density becomes an essential requirement for applications such as in conceptual landscape design, simulation and analysis, and mobile mapping. We discuss concepts of generalization and working principles as well as the concept of level-of-abstraction. We furthermore present three exemplary automated techniques for generalizing 3D landscape models, including a geometric generalization technique that generates discrete iso-surfaces of 3D terrain models in real-time, a geometric generalization technique for site and building models, and a real-time generalization lens technique.}, author = {Glander, Tassilo and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Proceedings of the annual conference of Digital Landscape Architecture (DLA)}, editor = {Buhmann, Erich and Ervin, Stephen and Tomlin, Dana and Pietsch, Matthias}, journal = {Peer Reviewed Proceedings Digital Landscape Architecture 2011: Teaching & Learning with Digital Methods & Tools}, month = 5, pages = {127-135}, title = {Concepts for Automatic Generalization of Virtual 3D Landscape Models}, year = 2011 }
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  Towards 3D Interaction Services for 3D Geovirtual Environments Klimke, Jan (2011).
  [ BibTeX ] [ Details ]
   
  @techreport{K2011, abstract = {Service-oriented architectures provide a flexible approach for 3D geodata access, processing, management and visualization. Services for 3D visualization allow for reliable, high quality visualization on client platforms that were otherwise not capable of storing, mapping, or rendering of 3D geodata. This extends the range of applications using 3D visualization of such data. While approaches for interactive visualization on lightweight clients exist, especially camera interaction remains a challenging task. Thin client applications do not have the information necessary for user interaction that provides, e.g., collision detection with scene object or assisting 3D camera control. This report provides an overview over the current status of my work in the area of interactive, service-based systems for 3D geovisualization. It outlines progress made in creating useful camera services delivering camera specifications derived from 3D geometry and semantic city model data. Further, my current research in progress is outlined.}, author = {Klimke, Jan}, title = {Towards 3D Interaction Services for 3D Geovirtual Environments}, year = 2011 }
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  A Visual Analysis and Design Tool for Planning Software Reengineerings. Beck, Martin; Trümper, Jonas; Döllner, Jürgen (2011). 54-61.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BTD2011, abstract = {Reengineering complex software systems represents a non-trivial process. As a fundamental technique in software engineering, reengineering includes (a) reverse engineering the as-is system design, (b) identifying a set of transformations to the design, and (c) applying these transformations. While methods a) and c) are widely supported by existing tools, identifying possible transformations to improve architectural quality is not well supported and, therefore, becomes increasingly complex in aged and large software systems. In this paper we present a novel visual analysis and design tool to support software architects during reengineering tasks in identifying a given software's design and in visually planning quality-improving changes to its design. The tool eases estimating effort and change impact of a planned reengineering. A prototype implementation shows the proposed technique's feasibility. Three case studies conducted on industrial software systems demonstrate usage and scalability of our approach.}, author = {Beck, Martin and Trümper, Jonas and Döllner, Jürgen}, booktitle = {Proceedings of the 6th IEEE International Workshop on Visualizing Software for Understanding and Analysis}, pages = {54-61}, publisher = {IEEE Computer Society}, title = {A Visual Analysis and Design Tool for Planning Software Reengineerings}, year = 2011 }
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  Service-oriented interactive 3D visualization of massive 3D city models on thin clients. Hildebrandt, Dieter; Klimke, Jan; Hagedorn, Benjamin; Döllner, Jürgen (2011). 1--1.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Hildebrandt2011, address = {New York, New York, USA}, author = {Hildebrandt, Dieter and Klimke, Jan and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications - COM.Geo '11}, pages = {1--1}, publisher = {ACM Press}, title = {Service-oriented interactive 3D visualization of massive 3D city models on thin clients}, year = 2011 }
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  Multiscale Visualization of 3D Geovirtual Environments Using View-Dependent Multi-Perspective Views. Pasewaldt, Sebastian; Trapp, Matthias; Döllner, Jürgen in Journal of WSCG, (V. Skala, red.) (2011). 19(3) 111-118.
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  @article{PTD11, abstract = {3D geovirtual environments (GeoVEs), such as virtual 3D city models or landscape models, are essential visualization tools for effectively communicating complex spatial information. In this paper, we discuss how these environments can be visualized using multi-perspective projections based on view-dependent global deformations. Multi-perspective projections enable 3D visualization similar to panoramic maps, increasing overview and information density in depictions of 3D GeoVEs. To make multi-perspective views an effective medium, they must adjust to the orientation of the virtual camera controlled by the user and constrained by the environment. Thus, changing multi-perspective camera configurations typically require the user to manually adapt the global deformation — an error prone, non-intuitive, and often time-consuming task. Our main contribution comprises a concept for the automatic and view-dependent interpolation of different global deformation preset configurations. Applications and systems that implement such view-dependent global deformations, allow users to smoothly and steadily interact with and navigate through multi-perspective 3D GeoVEs.}, author = {Pasewaldt, Sebastian and Trapp, Matthias and Döllner, Jürgen}, editor = {Skala, Václav}, journal = {Journal of WSCG}, month = 2, number = 3, pages = {111-118}, publisher = {UNION Agency – Science Press}, title = {Multiscale Visualization of 3D Geovirtual Environments Using View-Dependent Multi-Perspective Views}, volume = 19, year = 2011 }
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  Integrating 3D data in service-based visualization systems. Klimke, Jan; Hildebrandt, Dieter; Hagedorn, Benjamin; Döllner, Jürgen (2011). 1.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Klimke2011, address = {New York, New York, USA}, author = {Klimke, Jan and Hildebrandt, Dieter and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications - COM.Geo '11}, pages = 1, publisher = {ACM Press}, title = {Integrating 3D data in service-based visualization systems}, year = 2011 }
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  Strategies for Visualizing 3D Points-of-Interest on Mobile Devices. Trapp, Matthias; Schneider, Lars; Lehmann, Christine; Holz, Norman; Döllner, Jürgen in Journal of Location Based Services (JLBS) (2011). 5(2) 79-99.
  [ BibTeX ] [ Details ]
   
  @article{TSLHD11, abstract = {3D virtual environments are increasingly used as general-purpose medium for communicating spatial information. In particular, virtual 3D city models have numerous applications such as car navigation, city marketing, tourism, and gaming. In these applications, points-of-interest (POI) play a major role since they typically represent features relevant for specific user tasks and facilitate effective user orientation and navigation through the 3D virtual environment. In this paper, we present strategies that aim at effectively visualizing points-of-interest in a 3D virtual environment used on mobile devices. Here, we additionally have to face the "keyhole" situation, i.e., the users can realize only a small part of the environment due to the limited view space and resolution. For the effective visualization of points-of-interest in 3D virtual environments we propose to combine specialized occlusion management for 3D scenes together with visual cues that handle out-of-frame points-of-interest. We also discuss general aspects and definitions of points-of-interest in the scope of 3D models and outline a prototype implementation of the mobile 3D viewer application based on the presented concepts. In addition, we give a first performance evaluation with respect to rendering speed and power consumptions.}, address = {Bristol, PA, USA}, author = {Trapp, Matthias and Schneider, Lars and Lehmann, Christine and Holz, Norman and Döllner, Jürgen}, booktitle = {Journal of Location Based Services (JLBS)}, journal = {Journal of Location Based Services (JLBS)}, month = 6, number = 2, pages = {79-99}, publisher = {Taylor & Francis, Inc.}, title = {Strategies for Visualizing 3D Points-of-Interest on Mobile Devices}, volume = 5, year = 2011 }
• 
  Monitoring Code Quality and Development Activity by Software Maps. Bohnet, Johannes; Döllner, Jürgen (2011). 9-16.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BD2011, abstract = {Software development projects are difficult to manage, in general, due to the friction between completing system features and, at the same time, obtaining a high degree of code quality to ensure maintainability of the system in the future. A major challenge of this optimization problem is that code quality is less visible to stakeholders in the development process, particularly, to the management. In this paper, we describe an approach for automated software analysis and monitoring of both quality-related code metrics and development activities by means of software maps. A software map represents an adaptive, hierarchical representation of software implementation artifacts such as source code files being organized in a modular hierarchy. The maps can express and combine information about software development, software quality, and system dynamics, they can systematically be specified, automatically generated, and organized by templates. The maps aim at supporting decision-making processes. For example, they facilitate to decide where in the code an increase of quality would be beneficial both for speeding up current development activities and for reducing risks of future maintenance problems. Due to their high degree of expressiveness and their instantaneous generation, the maps additionally serve as up-to-date information tools, bridging an essential information gap between management and development, improve awareness, and serve as early risk detection instrument. The software map concept and its tool implementation are evaluated by means of two case studies on large industrially developed software systems.}, author = {Bohnet, Johannes and Döllner, Jürgen}, booktitle = {Proceedings of the IEEE ACM ICSE Workshop on Managing Technical Debt}, month = 5, pages = {9-16}, title = {Monitoring Code Quality and Development Activity by Software Maps}, year = 2011 }

2010 [ nach oben ]

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  Understanding Complex Multithreaded Software Systems by Using Trace Visualization. Trümper, Jonas; Bohnet, Johannes; Döllner, Jürgen (2010). 133-142.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TBD10, abstract = {Understanding multithreaded software systems is typically a tedious task: Due to parallel execution and interactions between multiple threads, such a system's runtime behavior is often much more complex than the behavior of a single-threaded system. For many maintenance activities, system understanding is a prerequisite. Hence, tasks such as bug fixing or performance optimization are highly demanding in the case of multithreaded systems. Unfortunately, state-of-the-art tools for system understanding and debuggers provide only limited support for these systems. We present a dynamic analysis and visualization technique that helps developers in understanding multithreaded software systems in general and in identifying performance bottlenecks in particular. The technique first performs method boundary tracing. Second, developers perform a post-mortem analysis of a system's behavior using visualization optimized for trace data of multithreaded software systems. The technique enables developers to understand how multiple threads collaborate at runtime. The technique is integrated into a professional and scalable tool for visualizing the behavior of complex software systems. In case studies, we have tested the technique with industrially developed, multithreaded software systems to understand system behavior and to identify multithreading-related performance bottlenecks.}, author = {Trümper, Jonas and Bohnet, Johannes and Döllner, Jürgen}, booktitle = {Proceedings of the 5th International Symposium on Software Visualization}, month = 10, pages = {133-142}, publisher = {ACM}, title = {Understanding Complex Multithreaded Software Systems by Using Trace Visualization}, year = 2010 }
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  Combining Synchronous and Asynchronous Collaboration within 3D City Models. Klimke, Jan; Döllner, Jürgen in LNCS, S. I. Fabrikant, Reichenbacher, T., van Kreveld, M., Schlieder, C. (reds.) (2010).
  [ BibTeX ] [ Details ]
   
  @inproceedings{KD10b, abstract = {This paper presents and approach for combining spatially distributed synchronous and asynchronous collaboration within 3D city models. Applications use these models as additional communication medium - beside traditional ones like chat, audio, and video conferences - to facilitate communication of georeferenced and geospatial information. Among many challenges collaboration tools should support both the communication with other collaborators and their awareness of the current collaboration context. To support knowledge construction and gathering, we have designed a collaboration tool that facilitates (a) creation of comments that have 3D references to the virtual 3D city model and (b) information about the context in which these comments are reated. The synchronous collaboration in connection with the creation of non volatile, precisely georeferenced units of information allows users a comprehensible form of cooperation in spatially distributed settings. In our approach media breaks are avoided by using a single 3D user interface to avoid media switches and disruption in working processes. By visualizing the information associated with a geographic feature or 3D geometry of a virtual 3D city model a coherent representation of content and reference is possible.}, author = {Klimke, Jan and Döllner, Jürgen}, booktitle = {Sixth International Conference, GIScience 2010, Zürich, Switzerland, Sep. 14-17 2010, Proceedings}, editor = {Fabrikant, S.I. and Reichenbacher, T. and van Kreveld, M. and Schlieder, C.}, number = 6292, publisher = {Springer}, series = {LNCS}, title = {Combining Synchronous and Asynchronous Collaboration within 3D City Models}, year = 2010 }
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  Visualization of Multithreaded Behavior to Facilitate Maintenance of Complex Software Systems. Trümper, Jonas; Bohnet, Johannes; Voigt, Stefan; Döllner, Jürgen (2010). 325-330.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TBVD10, abstract = {Maintenance accounts for the major part of a software system's total costs. Therein, program comprehension is an important, but complex activity: Typically, up-to-date documentation is not available, so the main reliable source of information on the implementation represent the artifacts of the system's implementation. Understanding software systems is difficult, in particular, if multithreading concepts are involved because state-of-the art development tools provide only limited support for maintenance activities. In addition, concurrency is often not directly reflected by the source code, i.e., there is only a non-obvious correlation between control structures in the source code and a system's runtime behavior. We present a program comprehension technique that helps to analyze and understand runtime behavior of multithreaded software systems and, thereby, facilitates software maintenance tasks. Our approach contains the following concepts: First, light-weight dynamic analysis records executed method calls at runtime. Second, visualization of multithreading trace data allows developers to explore the system behavior post-mortem. The technique forms part of a scalable tool suite for understanding the behavior of complex software systems. We also show how to apply the technique on industrial software systems to solve common maintenance problems.}, author = {Trümper, Jonas and Bohnet, Johannes and Voigt, Stefan and Döllner, Jürgen}, booktitle = {Proceedings of the 7th International Conference on the Quality of Information and Communications Technology}, month = 9, pages = {325-330}, publisher = {IEEE Computer Society}, title = {Visualization of Multithreaded Behavior to Facilitate Maintenance of Complex Software Systems}, year = 2010 }
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  Anisotropic Kuwahara Filtering with Polynomial Weighting Functions. Kyprianidis, Jan Eric; Semmo, Amir; Kang, Henry; Döllner, Jürgen (2010).
  [ BibTeX ] [ Details ]
   
  @other{KSKD10a, abstract = {In this work we present new weighting functions for the anisotropic Kuwahara filter. The anisotropic Kuwahara filter is an edge-preserving filter that is especially useful for creating stylized abstractions from images or videos. It is based on a generalization of the Kuwahara filter that is adapted to the local shape of features. For the smoothing process, the anisotropic Kuwahara filter uses weighting functions that use convolution in their definition. For an efficient implementation, these weighting functions are therefore usually sampled into a texture map. By contrast, our new weighting functions do not require convolution and can be efficiently computed directly during the filtering in real-time. We show that our approach creates output of similar quality as the original anisotropic Kuwahara filter and present an evaluation scheme to compute the new weighting functions efficiently by using rotational symmetries.}, author = {Kyprianidis, Jan Eric and Semmo, Amir and Kang, Henry and Döllner, Jürgen}, booktitle = {NPAR Poster Session}, month = 6, title = {Anisotropic Kuwahara Filtering with Polynomial Weighting Functions}, year = 2010 }
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  3D Feature Surface Properties and Their Application in Geovisualization. Lorenz, Haik; Döllner, Jürgen in Computers, Environment and Urban Systems (CEUS) (2010). 34(6) 476--483.
  [ BibTeX ] [ Details ]
   
  @article{LD10a, abstract = {New acquisition methods have increased the availability of surface property data that capture location-dependent data on feature surfaces. However, these data are not supported as fully in the geovisualization of the Digital City as established data categories such as feature attributes, 2D rasters, or geometry. Consequently, 3D surface properties are largely excluded from the information extraction and knowledge creation process of geovisualization despite their potential for being an effective tool in many such tasks. To overcome this situation, this paper examines the benefits of a better integration into geovisualization systems in terms of two examples and discusses technological foundations for surface property support. The main contribution is the identification of computer graphics techniques as a suitable basis for such support. This way, the processing of surface property data fits well into existing visualization systems. This finding is demonstrated through an interactive prototypic visualization system that extends an existing system with surface property support. While this prototype concentrates on technology and neglects user-related and task-related aspects, the paper includes a discussion on challenges for making surface properties accessible to a wider audience.}, author = {Lorenz, Haik and Döllner, Jürgen}, journal = {Computers, Environment and Urban Systems (CEUS)}, number = 6, pages = {476--483}, publisher = {Elsevier}, title = {3D Feature Surface Properties and Their Application in Geovisualization}, volume = 34, year = 2010 }
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  Image-Based, Interactive Visualization of Complex 3D Geovirtual Environments on Lightweight Devices. Hildebrandt, Dieter; Hagedorn, Benjamin; Döllner, Jürgen (2010).
  [ BibTeX ] [ Details ]
   
  @misc{HHD10, abstract = {In this paper, we present strategies for service-oriented, standards and image-based 3D geovisualization that have the potential to provide interactive vi-sualization of complex 3D geovirtual environments (3DGeoVE) on lightweight devices. In our approach, interactive geovisualization clients retrieve sets of 2D images of projective views of 3DGeoVEs generated by a 3D rendering service. As the key advantage of the image-based approach, the complexity that a client is exposed to for displaying a visual representation is reduced to a constant factor primarily depending on the image resolution. To provide users with a high degree of interactivity, we propose strategies that are based on additional service-side functionality and on exploiting multiple layers of information encoded into the images for the local reconstruction of visual representations of the remote 3DGeoVE. The use of service-orientation and standards facilitates designing distributed 3D geovisualization systems that are open, interoperable and can easily be adapted to changing requirements. We demonstrate the validity of the proposed strategies by presenting several image-based 3D clients for the case of virtual 3D city models.}, author = {Hildebrandt, Dieter and Hagedorn, Benjamin and Döllner, Jürgen}, booktitle = {Proceedings of the 7th International Symposium on LBS & TeleCartography}, title = {Image-Based, Interactive Visualization of Complex 3D Geovirtual Environments on Lightweight Devices}, year = 2010 }
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  High-Quality Non-Planar Projections Using Real-time Piecewise Perspective Projections. Lorenz, Haik; Döllner, Jürgen in Computer Vision, Imaging and Computer Graphics. Theory and Applications. International Joint Conference, VISIGRAPP 2009, Lisboa, Portugal, February 5-8, 2009. Revised Selected Papers, A. K. Ranchordas, Pereira, J. ~ao M., Araújo, H. J., Tavares, J. ~ao M. R. S. (reds.) (2010). (Vol. 68) 45--58.
  [ BibTeX ] [ Details ]
   
  @inbook{LD10b, abstract = {This paper presents an approach to real-time rendering of non-planar projections with a single center and straight projection rays. Its goal is to provide the same optimal and consistent image quality GPUs deliver for perspective projections. It therefor renders the result directly without image resampling. In contrast to most object-space approaches, it does not evaluate non-linear functions on the GPU, but approximates the projection itself by a set of perspective projection pieces. Within each piece, graphics hardware can provide optimal image quality. The result is a coherent and crisp rendering. Procedural textures and stylization effects greatly benefit from our method as they usually rely on screen-space operations. The real-time implementation runs entirely on GPU. It replicates input primitives on demand and renders them into all relevant projection pieces. The method is independent of the input mesh density and is not restricted to static meshes. Thus, it is well suited for interactive applications. We demonstrate an analytic and a freely designed projection based on our method.}, author = {Lorenz, Haik and Döllner, Jürgen}, booktitle = {Computer Vision, Imaging and Computer Graphics. Theory and Applications. International Joint Conference, VISIGRAPP 2009, Lisboa, Portugal, February 5-8, 2009. Revised Selected Papers}, editor = {Ranchordas, Alpesh Kumar and Pereira, Jo~ao Madeiras and Araújo, Hélder J. and Tavares, Jo~ao Manuel R. S.}, pages = {45--58}, publisher = {Springer}, series = {Communications in Computer and Information Science}, title = {High-Quality Non-Planar Projections Using Real-time Piecewise Perspective Projections}, volume = 68, year = 2010 }
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  Effiziente Verschattungsberechnung für die Solarpotenzialanalyse unter Berücksichtigung der Einstrahlungsintensität. Engel, Juri; Döllner, Jürgen (2010).
  [ BibTeX ] [ Details ]
   
  @inproceedings{ED10b, abstract = {In diesem Beitrag stellen wir ein Verfahren zur effizienten Berechnung von Verschattungsdaten vor, das insbesondere die Einstrahlungsintensität berücksichtigt und einen zentralen Bestandteil von Solarpotenzialanalysen bildet. Das Verfahren basiert auf der 3D-Analyse einer virtuellen 3D-Umgebung und nutzt dabei die Funktionalität von 3DGrafikhardware, um die Berechnung zu beschleunigen, indem 3D-Analyserechnungen durch bildbasierte Verfahren approximiert werden. Bisherige Verfahren berechnen den Verschattungsgrad für eine definierte Zeitspanne, berücksichtigen aber nicht wann in dieser Zeitspanne die analysierte Fläche verschattet ist. Dies bestimmt jedoch maßgeblich die potenziell erzeugbare Energiemenge. Im vorgestellten Verfahren werden hierfür die für die Analyse herangezogenen Sonnenpositionen anhand der Einstrahlungsintensität gewichtet. Aus den somit erzeugten Verschattungsdaten mit gewichteten Werten kann die Reduktion der potenziell erzeugbaren Energiemenge aufgrund von zeitweiliger Verschattung präzise errechnet werden.}, address = {Vienna}, author = {Engel, Juri and Döllner, Jürgen}, booktitle = {Tagungsband der 3-Ländertagung DGPF}, title = {Effiziente Verschattungsberechnung für die Solarpotenzialanalyse unter Berücksichtigung der Einstrahlungsintensität}, year = 2010 }
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  Erreichbarkeitskarten zur Visualisierung der Mobilitätsqualität im ÖPNV. Glander, Tassilo; Kramer, Martin; Döllner, Jürgen in Kartographische Nachrichten (2010).
  [ BibTeX ] [ Details ]
   
  @article{GKD10, abstract = {Mobilitätsqualität wird von ÖPNV-Nutzern situativ unmittelbar, aber systematisch nur diffus wahrgenommen.Wir stellen einen Ansatz vor, bei dem das vom ÖPNV-Betreiber bereitgestellte Verbindungsauskunftssystem genutzt wird, um durch eine Menge von Einzelverbindungsanfragen eine Erreichbarkeitskarte für das gesamte Verkehrsgebiet zu erstellen. Neben Erreichbarkeitskarten mit einem Startpunkt lassen sich auch mehrere Startpunkte mit gemittelter Erreichbarkeit berechnen. Die Visualisierung als farbkodierte Erreichbarkeitskarte oder Erreichbarkeitsterrain ermöglicht eine effektive Kommunikation der Mobilitätsqualität einer Region.}, author = {Glander, Tassilo and Kramer, Martin and Döllner, Jürgen}, journal = {Kartographische Nachrichten}, publisher = {Kirschbaum Verlag}, title = {Erreichbarkeitskarten zur Visualisierung der Mobilitätsqualität im ÖPNV}, year = 2010 }
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  Anisotropic Kuwahara Filtering on the GPU. Kyprianidis, Jan Eric; Kang, Henry; Döllner, Jürgen in GPU Pro – Advanced Rendering Techniques, W. Engel (red.) (2010). 247--264.
  [ BibTeX ] [ URL ] [ Details ]
   
  @incollection{KKD10, author = {Kyprianidis, Jan Eric and Kang, Henry and Döllner, Jürgen}, booktitle = {GPU Pro – Advanced Rendering Techniques}, editor = {Engel, W.}, pages = {247--264}, publisher = {AK Peters}, title = {Anisotropic Kuwahara Filtering on the GPU}, year = 2010 }
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  Communication of Digital Cultural Heritage in Public Spaces by the Example of Roman Cologne. Trapp, Matthias; Semmo, Amir; Pokorski, Rafael; Herrmann, Claus-Daniel; Döllner, Jürgen; Eichhorn, Michael; Heinzelmann, Michael in Lecture Notes in Computer Science (LNCS), M. Ioannides (red.) (2010). 262-276.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TSPHDEH10, abstract = {The communication of cultural heritage in public spaces such as museums or exhibitions, gain more and more importance during the last years. The possibilities of interactive 3D applications open a new degree of freedom beyond the mere presentation of static visualizations, such as pre-produced video or image data. A user is now able to directly interact with 3D virtual environments that enable the depiction and exploration of digital cultural heritage artefacts in real-time. However, such technology requires concepts and strategies for guiding a user throughout these scenarios, since varying levels of experiences within interactive media can be assumed. This paper presents a concept as well as implementation for communication of digital cultural heritage in public spaces, by example of the project Roman Cologne. It describes the results achieved by an interdisciplinary team of archaeologists, designers, and computer graphics engineers with the aim to virtually reconstruct an interactive high-detail 3D city model of Roman Cologne.}, author = {Trapp, Matthias and Semmo, Amir and Pokorski, Rafael and Herrmann, Claus-Daniel and Döllner, Jürgen and Eichhorn, Michael and Heinzelmann, Michael}, booktitle = {Digital Heritage, Proceedings of 3rd EuroMed Conference}, editor = {Ioannides, M.}, month = 11, note = {Best-Paper-Award}, pages = {262-276}, publisher = {Springer-Verlag Berlin Heidelberg}, series = {Lecture Notes in Computer Science (LNCS)}, title = {Communication of Digital Cultural Heritage in Public Spaces by the Example of Roman Cologne}, year = 2010 }
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  ContextLua: Dynamic Behavioral Variations in Computer Games. Hosain Wasty, Benjamin; Semmo, Amir; Appeltauer, Malte; Steinert, Bastian; Hirschfeld, Robert (2010). 5:1--5:6.
  [ BibTeX ] [ Details ]
   
  @inproceedings{WSASH, abstract = {Behavioral variations are central to modern computer games as they are making the gameplay a more interesting user experience. However, these variations significantly add to the implementation complexity. We discuss the domain of computer games with respect to dynamic behavioral variations and argue that context-oriented programming is of special interest for this domain. This motivates our extension to the dynamic scripting language Lua, which is frequently used in the development of computer games. Our newly provided programming constructs allow game developers to use layers for defining and activating variations of the basic gameplay.}, author = {Hosain Wasty, Benjamin and Semmo, Amir and Appeltauer, Malte and Steinert, Bastian and Hirschfeld, Robert}, booktitle = {Proceedings of the 2nd International Workshop on Context-Oriented Programming}, pages = {5:1--5:6}, title = {ContextLua: Dynamic Behavioral Variations in Computer Games}, year = 2010 }
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  3D Isocontours – Real-time Generation and Visualization of 3D Stepped Terrain Models. Glander, Tassilo; Trapp, Matthias; Döllner, Jürgen S. Seipel, Lensch, H. (reds.) (2010). 17-20.
  [ BibTeX ] [ Details ]
   
  @inproceedings{GTD10, abstract = {Isocontours (also isopleths, isolines, level sets) are commonly used to visualize real-valued data defined over a 2D plane according to a set of given isovalues. To support the 3D landscape metaphor for information visualization, a 3D stepped terrain can be derived by lifting and extruding isolines to their particular isovalue, but typically requires triangulation of the resulting surface representation in a preprocessing step. We present a concept and rendering technique for triangle-based terrain models that provide interactive, adaptive generation and visualization of such stepped terrains without preprocessing. Our fully hardware-accelerated rendering technique creates additional step geometry for each triangle intersecting an iso-plane on-the-fly. Further, an additional interpolation schema facilitates smooth transition between established 3D terrain visualization and its stepped variant.}, address = {Norrköping, Sweden}, author = {Glander, Tassilo and Trapp, Matthias and Döllner, Jürgen}, booktitle = {Eurographics 2010 Shortpaper}, editor = {Seipel, Stefan and Lensch, Hendrik}, month = 5, pages = {17-20}, publisher = {The Eurographics Association}, title = {3D Isocontours – Real-time Generation and Visualization of 3D Stepped Terrain Models}, year = 2010 }
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  Stereo Coherence in Watercolour Rendering. Richardt, Christian; Kyprianidis, Jan Eric; Dodgson, Neil A. (2010).
  [ BibTeX ] [ Details ]
   
  @other{RKD10, abstract = {We investigate stereo coherence – or consistency of stereoscopic views – in non-photorealistic rendering (NPR) by example. We designed and carried out a pilot user study that compared stereoscopic animations created using two different watercolour rendering styles. The rendering styles use image-space and object-space noise respectively. A clear majority of participants preferred the object-based technique and found it more comfortable to watch than the image-space technique which suffers from the ‘shower door effect’. Based on these preliminary results, we conclude that stereo coherence is indeed a desirable property for non-photorealistic rendering techniques.}, author = {Richardt, Christian and Kyprianidis, Jan Eric and Dodgson, Neil A.}, booktitle = {Poster at Symposium on Computational Aesthetics (CAe) and Symposium on Non-Photorealistic Animation and Rendering (NPAR)}, month = 6, title = {Stereo Coherence in Watercolour Rendering}, year = 2010 }
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  Anisotropic Kuwahara Filtering with Polynomial Weighting Functions. Kyprianidis, Jan Eric; Semmo, Amir; Kang, Henry; Döllner, Jürgen (2010). 25--30.
  [ BibTeX ] [ Details ]
   
  @inproceedings{KSKD10b, abstract = {In this work we present new weighting functions for the anisotropic Kuwahara filter. The anisotropic Kuwahara filter is an edge-preserving filter that is especially useful for creating stylized abstractions from images or videos. It is based on a generalization of the Kuwahara filter that is adapted to the local shape of features. For the smoothing process, the anisotropic Kuwahara filter uses weighting functions that use convolution in their definition. For an efficient implementation, these weighting functions are therefore usually sampled into a texture map. By contrast, our new weighting functions do not require convolution and can be efficiently computed directly during the filtering in real-time. We show that our approach creates output of similar quality as the original anisotropic Kuwahara filter and present an evaluation scheme to compute the new weighting functions efficiently by using rotational symmetries.}, author = {Kyprianidis, Jan Eric and Semmo, Amir and Kang, Henry and Döllner, Jürgen}, booktitle = {Proc. EG UK Theory and Practice of Computer Graphics}, month = 9, pages = {25--30}, title = {Anisotropic Kuwahara Filtering with Polynomial Weighting Functions}, year = 2010 }
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  Interactive Rendering Techniques for Highlighting in 3D Geovirtual Environments. Trapp, Matthias; Beesk, Christian; Pasewaldt, Sebastian; Jürgen, Döllner in Lecture Notes in Geoinformation & Cartography (2010).
  [ BibTeX ] [ Details ]
   
  @inproceedings{TBPD10, abstract = {3D geovirtual environments (GeoVE), such as virtual 3D city and landscape models became an important tool for the visualization of geospatial information. Highlighting is an important component within a visualization framework and is essential for the user interaction within many applications. It enables the user to easily perceive active or selected objects in the context of the current interaction task. With respect to 3D GeoVE, it has a number of applications, such as the visualization of user selections, data base queries, as well as navigation aid by highlighting way points, routes, or to guide the user attention. The geometrical complexity of 3D GeoVE often requires specialized rendering techniques for the real-time image synthesis. This paper presents a framework that unifies various highlighting techniques and is especially suitable for the interactive rendering 3D GeoVE of high geometrical complexity.}, author = {Trapp, Matthias and Beesk, Christian and Pasewaldt, Sebastian and Jürgen, Döllner}, booktitle = {Proceedings of the 5th 3D GeoInfo Conference}, month = 11, publisher = {Springer}, series = {Lecture Notes in Geoinformation & Cartography}, title = {Interactive Rendering Techniques for Highlighting in 3D Geovirtual Environments}, year = 2010 }
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  Effiziente Verschattungsberechnung für die Solarpotenzialanalyse durch bildbasierte 3D-Analyse. Engel, Juri; Döllner, Jürgen in Proceedings of the GeoInformatik 2010 (2010).
  [ BibTeX ] [ Details ]
   
  @article{ED10a, abstract = {In diesem Paper stellen wir ein neues Verfahren zur effizienten Berechnung von Verschattungsdaten als zentralen Bestandteil einer Solarpopenzialanalyse vor. Erneuerbare Energien tragen maßgeblich dazu bei, die CO2 Emissionen zu reduzieren und von fossilen Rohstoffen unabhängiger zu werden. Private Investoren sowie auch Kommunen sind daran interessiert, potenzielle Flächen für die Anbringung von Solaranlagen zu identifizieren. Eine großflächige Identifikation von Flächen ist nur durch eine vollautomatische Solarpotenzialanalyse möglich. Der hier vorgestellte Algorithmus für die Verschattungsberechnung basiert auf der 3D-Analyse einer virtuellen 3D-Umgebung. Die Genauigkeit der Verschattungsberechnung ist maßgeblich von dem Zeitintervall für die Diskretisierung eines untersuchten Zeitraums abhängig. Mit unserem Verfahren ist die Berechnungszeit jedoch nahezu unabhängig von dem Zeitintervall. Zusätzlich nutzt es moderne Grafikhardware um die Berechnung zu beschleunigen, indem die 3D-Analyserechnungen durch bildbasierte Verfahren approximiert werden. We-der Erkennung noch explizite Modellierung von Gebäuden oder Vegetation sind für die Solarpotentialanalyse notwendig, was den Einsatz der effizienten Verschattungsanalyse in einer Vielzahl von Anwendungen und Systemen ermöglicht.}, author = {Engel, Juri and Döllner, Jürgen}, journal = {Proceedings of the GeoInformatik 2010}, publisher = {Wichmann Verlag}, title = {Effiziente Verschattungsberechnung für die Solarpotenzialanalyse durch bildbasierte 3D-Analyse}, year = 2010 }
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  Towards Automated Analysis and Visualization of Distributed Software Systems. Beck, Martin; Döllner, Jürgen (2010). 213-214.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BD10, abstract = {This paper sketches one approach to facilitate comprehension of distributed software systems. These systems gain more and more importance due to a paradigm shift in software systems and applications, evolving from single-chip solutions to multi-tiered web-based applications. For a single developer, it becomes increasingly difficult to cope with the complexity of such software systems. We propose a novel automated analysis and visualization technique that aims at the interactive exploration of static structures and behavior of distributed software systems. First, it automatically gathers communication data from the instrumented system components. Second, it generates a visual representation using a heuristic layout approach. Finally, it allows developers to interactively refine and explore this structural and behavioral information.}, author = {Beck, Martin and Döllner, Jürgen}, booktitle = {Proceedings of the International Symposium on Software Visualization}, pages = {213-214}, title = {Towards Automated Analysis and Visualization of Distributed Software Systems}, year = 2010 }
• 
  Web View Service Discussion Paper, Version 0.3.0, OGC 09-166r2. Hagedorn, Benjamin (2010).
  [ BibTeX ] [ URL ] [ Details ]
   
  @misc{OGCWVS2010, editor = {Hagedorn, Benjamin}, howpublished = {OGC Discussion Paper, OGC 09-166r2}, publisher = {Open Geospatial Consortium Inc.}, title = {Web View Service Discussion Paper, Version 0.3.0, OGC 09-166r2}, year = 2010 }
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  Towards Efficient Camera Interaction in Service-based 3D Geovirtual Environments. Klimke, J. (2010). 211--219.
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2010d, abstract = {Service based geovisualization helps to enable high quality 3D visualization with minimal requirements for clients regarding computational power or rendering capabilities. While interaction with 2D maps is quite well understood, interaction in 3D is more challenging due to its additional degrees of freedom that have to be controlled. So called smart interaction techniques can help a user to master this 3D complexity using standard 2D input devices. To do so, additional information about the 3D environment, which is used for visualization, is needed. Such data is not per se available in many of the applications of service-based 3D visualization. This report proposes to encapsulate parts of the interaction process into service components that can be deployed independently from client applications. This lowers the complexity of client implementations, that are possibly running on a small handheld devices, so data access and computation necessary for interaction can be externalized to faster systems, which may also have a faster, more reliable network connection. Such a decoupled paradigm enables the deployment of service-based visualization applications depending on the client device's capabilities regarding computational power or data access (access rights or networking bandwidth).}, author = {Klimke, J.}, organization = {Hasso-Plattner-Institut}, pages = {211--219}, title = {Towards Efficient Camera Interaction in Service-based 3D Geovirtual Environments}, year = 2010 }
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  Approaches to Image Abstraction for Photorealistic Depictions of Virtual 3D Models. Döllner, Jürgen; Kyprianidis, Jan Eric in Lecture Notes in Geoinformation and Cartography, G. Gartner, Ortag, F. (reds.) (2010). 263--277.
  [ BibTeX ] [ Details ]
   
  @inproceedings{DK10a, abstract = {In our contribution, we present approaches of automatic image abstraction, applied to images and image sequences derived as views of virtual 3D city models and landscape models. We first discuss the requirements of cartography-specific visualization based on the virtual globe metaphor as well as the specific characteristics and deficiencies of visualization based on photorealism. We introduce a concept that extends the classical visualization pipeline by cartography-specific functionality, object-space and image-space abstraction, which also represent the two principle ways for implementing cartographic visualization systems. Abstraction provides the prerequisites to visually communicate uncertainty, to simplify and filter detailed elements, and to clearly encode displayed information of complex geospatial information. In addition, it offers many degrees of freedom for artistic and stylistic design of cartographic products. Furthermore, we outline general working principles and implementation of an automatic image-space abstraction technique we developed that creates high-quality, simplified, stylistic illustrations from color images, videos, and 3D renderings.}, author = {Döllner, Jürgen and Kyprianidis, Jan Eric}, booktitle = {Cartography in Central and Eastern Europe}, editor = {Gartner, Georg and Ortag, Felix}, pages = {263--277}, publisher = {Springer}, series = {Lecture Notes in Geoinformation and Cartography}, title = {Approaches to Image Abstraction for Photorealistic Depictions of Virtual 3D Models}, year = 2010 }
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  Bestandsaktualisierung von 3D-Stadtmodellen durch Analyse von 3D-Punktwolken. Richter, Rico; Döllner, Jürgen (2010).
  [ BibTeX ] [ Details ]
   
  @inproceedings{RD10a, abstract = {In dieser Arbeit wird ein Verfahren zur Fortführung und Aktualisierung virtueller 3D-Stadtmodelle auf Basis automatischer Auswertung von LiDAR-Daten vorgestellt. Scanner-Technologien (z. B. LiDAR) ermöglichen die regelmäßige und kosteneffiziente Erfassung von Städten und Metropolregionen durch Befliegungen oder terrestrische Aufnahmen. Die Konstruktion eines 3D-Stadtmodells ist hingegen im Allgemeinen aufwändig, so dass die Aktualisierung eines bereits bestehenden 3D-Stadtmodells aus wirtschaftlicher Sicht effizienter durchgeführt werden muss. Mit dem hier vorgestellten Verfahren ist es möglich, bestehende 3D-Stadtmodelle und erfasste LiDAR-Daten in Echtzeit zu visualisieren und Veränderungen im Datenbestand automatisiert zu ermitteln. Unterschiede zwischen der tatsächlichen Bebauung und des im 3D-Stadtmodell vorhandenen Datenbestandes werden so zuverlässig erkannt, so dass eine nachfolgende manuelle Bestandsaktualisierung durch 3D-Stadtmodellwerkzeuge fokussiert durchgeführt werden kann.}, address = {Vienna}, author = {Richter, Rico and Döllner, Jürgen}, booktitle = {Tagungsband der 3-Ländertagung DGPF}, howpublished = {CD-Proceedings}, title = {Bestandsaktualisierung von 3D-Stadtmodellen durch Analyse von 3D-Punktwolken}, year = 2010 }
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  Combining Synchronous and Asynchronous Collaboration within 3D City Models. Klimke, Jan; Döllner, Jürgen S. I. Fabrikant, Reichenbacher, T., van Kreveld, M., Schlieder, C. (reds.) (2010). 115--129.
  [ BibTeX ] [ Details ]
   
  @inproceedings{Klimke2010b, address = {Zürich}, author = {Klimke, Jan and Döllner, Jürgen}, booktitle = {Sixth International Conference, GIScience 2010, Zürich, Switzerland, Sep. 14-17 2010, Proceedings}, editor = {Fabrikant, S.I. and Reichenbacher, T. and van Kreveld, M. and Schlieder, C}, pages = {115--129}, publisher = {Springer}, title = {Combining Synchronous and Asynchronous Collaboration within 3D City Models}, year = 2010 }
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  Geospatial Annotations for 3D Environments and their WFS-based Implementation. Klimke, Jan; Döllner, Jürgen in Lecture Notes in Geoinformation and Cartography, M. Painho, Santos, M. Y., Pundt, H. (reds.) (2010). 379--397.
  [ BibTeX ] [ URL ] [ Details ]
   
  @inproceedings{Klimke2010c, address = {Berlin, Heidelberg}, author = {Klimke, Jan and Döllner, Jürgen}, booktitle = {Geospatial Thinking}, editor = {Painho, M and Santos, M Y and Pundt, H}, pages = {379--397}, publisher = {Springer}, series = {Lecture Notes in Geoinformation and Cartography}, title = {Geospatial Annotations for 3D Environments and their WFS-based Implementation}, year = 2010 }
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  Towards Advanced and Interactive Web Perspective View Services. Hagedorn, Benjamin; Hildebrandt, Dieter; Döllner, Jürgen in Developments in 3D Geo-Information Sciences (2010). 33--51.
  [ BibTeX ] [ Details ]
   
  @inbook{hagedorn2010towards, abstract = {The Web Perspective View Service (WPVS) generates 2D images of perspective views of 3D geovirtual environments (e.g., virtual 3D city models) and represents one fundamental class of portrayal services. As key advantage, this image-based approach can be deployed across arbitrary networks due to server-side 3D rendering and 3D model management. However, restricted visualization and interaction capabilities of WPVS-based applications represent its main weaknesses. To overcome these limitations, we present the concept and an implementation of the WPVS++, a WPVS extension, which provides A) additional thematic information layers for generated images and B) additional service operations for requesting spatial and thematic information. Based on these functional extensions, WPVS++ clients can implement various 3D visualization and interaction features without changing the underlying working principle, which leads to an increased degree of interactivity and is demonstrated by prototypic web-based client applications.}, author = {Hagedorn, Benjamin and Hildebrandt, Dieter and Döllner, Jürgen}, booktitle = {Developments in 3D Geo-Information Sciences}, pages = {33--51}, publisher = {Springer}, series = {Lecture Notes in Geoinformation and Cartography}, title = {Towards Advanced and Interactive Web Perspective View Services}, year = 2010 }
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  Service-Based, Interactive Portrayal of 3D Geovirtual Environments. Hagedorn, Benjamin in Proceedings of the 4th Ph.D. Retreat of the HPI Research School on Service-oriented Systems Engineering, C. Meinel, Plattner, H., Döllner, J., Weske, M., Polze, A., Hirschfeld, R., Naumann, F., Giese, H. (reds.) (2010). 13:1--13:10.
  [ BibTeX ] [ URL ] [ Details ]
   
  @incollection{hagedorn2010servicebased, abstract = {This report summarizes my work in the HPI Research School on Service Oriented Systems Engineering. It motivates and points out the underlying research questions in the field of service-based 3D portrayal of large and complex 3D geovirtual envi- ronments, presents my approach to solving these questions, and demonstrates and highlights results by example. A focus is on my work during the past months.}, author = {Hagedorn, Benjamin}, booktitle = {Proceedings of the 4th Ph.D. Retreat of the HPI Research School on Service-oriented Systems Engineering}, editor = {Meinel, Christoph and Plattner, Hasso and Döllner, Jürgen and Weske, Mathias and Polze, Andreas and Hirschfeld, Robert and Naumann, Felix and Giese, Holger}, pages = {13:1--13:10}, publisher = {Universitätsverlag Potsdam}, series = {Technische Berichte des Hasso-Plattner-Instituts für Softwaresystemtechnik an der Universität Potsdam}, title = {Service-Based, Interactive Portrayal of 3D Geovirtual Environments}, type = {technical report}, year = 2010 }
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  Automated Image-Based Abstraction of Aerial Images. Semmo, Amir; Kyprianidis, Jan Eric; Döllner, Jürgen in Geospatial Thinking, M. Painho, Santos, M. Y., Pundt, H. (reds.) (2010). 359-378.
  [ BibTeX ] [ Details ]
   
  @incollection{SKD10, abstract = {Aerial images represent a fundamental type of geodata with a broad range of applications in GIS and geovisualization. The perception and cognitive processing of aerial images by the human, however, still is faced with the specific limitations of photorealistic depictions such as low contrast areas, unsharp object borders as well as visual noise. In this paper we present a novel technique to automatically abstract aerial images that enhances visual clarity and generalizes the contents of aerial images to improve their perception and recognition. The technique applies non-photorealistic image processing by smoothing local image regions with low contrast and emphasizing edges in image regions with high contrast. To handle the abstraction of large images, we introduce an image tiling procedure that is optimized for post-processing images on GPUs and avoids visible artifacts across junctions. This is technically achieved by filtering additional connection tiles that overlap the main tiles of the input image. The technique also allows the generation of different levels of abstraction for aerial images by computing a mipmap pyramid, where each of the mipmap levels is filtered with adapted abstraction parameters. These mipmaps can then be used to perform level-of-detail rendering of abstracted aerial images. Finally, the paper contributes a study to aerial image abstraction by analyzing the results of the abstraction process on distinctive visible elements in common aerial image types. In particular, we have identified a high abstraction straction potential in landscape images and a higher benefit from edge enhancement in urban environments.}, author = {Semmo, Amir and Kyprianidis, Jan Eric and Döllner, Jürgen}, booktitle = {Geospatial Thinking}, editor = {Painho, Marco and Santos, Maribel Yasmina and Pundt, Hardy}, month = 5, pages = {359-378}, publisher = {Springer}, series = {Lecture Notes in Geoinformation and Cartography}, title = {Automated Image-Based Abstraction of Aerial Images}, year = 2010 }
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  Image-based, interactive visualization of complex 3D geovirtual environments on lightweight devices. hildebrandt, dieter; hagedorn, benjamin; döllner, jürgen G. Gartner (red.) (2010). 52--71.
  [ BibTeX ] [ Details ]
   
  @inproceedings{hildebrandt2010imagebased, abstract = {In this paper, we present strategies for service-oriented, standards and image-based 3D geovisualization that have the potential to provide interactive vi-sualization of complex 3D geovirtual environments (3DGeoVE) on lightweight devices. In our approach, interactive geovisualization clients retrieve sets of 2D images of projective views of 3DGeoVEs generated by a 3D rendering service. As the key advantage of the image-based approach, the complexity that a client is exposed to for displaying a visual representation is reduced to a constant factor primarily depending on the image resolution. To provide users with a high degree of interactivity, we propose strategies that are based on additional service-side functionality and on exploiting multiple layers of information encoded into the images for the local reconstruction of visual representations of the remote 3DGeoVE. The use of service-orientation and standards facilitates designing distributed 3D geovisualization systems that are open, interoperable and can easily be adapted to changing requirements. We demonstrate the validity of the proposed strategies by presenting several image-based 3D clients for the case of virtual 3D city models.}, address = {Guangzhou, China}, author = {hildebrandt, dieter and hagedorn, benjamin and döllner, jürgen}, booktitle = {Proceedings of the 7th International Symposium on LBS and TeleCartography}, editor = {Gartner, Georg}, pages = {52--71}, title = {Image-based, interactive visualization of complex 3D geovirtual environments on lightweight devices}, year = 2010 }
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  Interactive Rendering to Perspective Texture-Atlases. Trapp, Matthias; Döllner, Jürgen S. Seipel, Lensch, H. (reds.) (2010). 81-84.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TD10, abstract = {The image-based representation of geometry is a well known concept in computer graphics. Due to z-buffering, the derivation of such representations using render-to-texture delivers only information of the nearest fragments. Often, transparency-based visualization techniques, e.g., ghost views, also require information of occluded fragments. These can be captured using multi-pass rendering techniques such as depth-peeling or stencil-routed A-buffers on a per-fragment basis. This paper presents an alternative rendering technique that enables the derivation image-based representations on a per-object or per-primitive level within a single rendering pass. We use a dynamic 3D texture atlas that is parameterized on a per-frame basis. Then, prior to rasterization, the primitives are transformed to their respective position within the texture atlas, using vertex-displacement in screen space.}, address = {Norrköping, Sweden}, author = {Trapp, Matthias and Döllner, Jürgen}, booktitle = {Eurographics 2010 Shortpaper}, editor = {Seipel, Stefan and Lensch, Hendrik}, month = 5, pages = {81-84}, publisher = {The Eurographics Association}, title = {Interactive Rendering to Perspective Texture-Atlases}, year = 2010 }
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  Geospatial Annotations for 3D Environments and their WFS-based Implementation. Klimke, Jan; Döllner, Jürgen in Lecture Notes in Geoinformation and Cartography, M. Painho, Santos, M. Y., Pundt, H. (reds.) (2010). 379-397.
  [ BibTeX ] [ Details ]
   
  @inproceedings{KD10a, abstract = {Collaborative geovisualization provides effective means to communicate spatial information among a group of users. Annotations as one key element of collaborative geovisualization systems enable comprehension of collaboration processes and support time-shifted communication. By annotations we refer to user-generated information such as remarks, comments, findings and any other information related to the 3D environment. They have to be efficiently modeled, stored and visualized while precisely retaining their spatial reference and creation context. Existing models for an-notations generally do not fully support spatial references and, therefore, do not fully take advantage of the spatial relationships associated with annotations. This paper presents a GML-based data model for geospatial annotations that explicitly incorporates spatial references and allows different types of annotations to be stored together with their context of creation. With this approach annotations can be represented as first-class spatial features. Consequently, annotations can be seamlessly integrated into their 3D environment and the author's original intention and message can be better expressed and understood. An OGC Web Feature Service is used as standardized interface for storage and retrieval of annotations, which assures data interoperability with existing geodata infrastructures. We have identi-fied three types of annotation subjects, namely geographic features, geometry, and scene views, represented by their corresponding 2D/3D geometry. The model also defines a point-based approximation for complex geometry, such that annotations can also be used by client application with limited abilities regarding display size, bandwidth or geometry handling. Furthermore we extended our model by annotations that can contain 3D geometry besides textual information. In this way the expressiveness of annotations can be further enhanced for communicating spatial relationships such as distances or arrangements of geographic features.}, author = {Klimke, Jan and Döllner, Jürgen}, booktitle = {Geospatial Thinking}, editor = {Painho, M. and Santos, M.Y. and Pundt, H.}, pages = {379-397}, publisher = {Springer}, series = {Lecture Notes in Geoinformation and Cartography}, title = {Geospatial Annotations for 3D Environments and their WFS-based Implementation}, year = 2010 }
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  Überlegungen zum stufenlosen Übergang zwischen verschieden generalisierten 3D-Stadtmodellrepräsentationen. Glander, Tassilo; Baresel, Janett; Döllner, Jürgen (2010).
  [ BibTeX ] [ Details ]
   
  @inproceedings{GBD10, abstract = {Generalisierungsalgorithmen für virtuelle 3D-Gebäude- und Stadtmodelle leiten aus detaillierten Repräsentationen weniger detaillierte Repräsentationen in unterschiedlich starkem Generalisierungsgrad ab. Für eine kartographisch optimierte Darstellung von 3D-Stadtmodellen in interaktiven Anwendungen muss abhängig vom Maßstab bzw. vom Abstand zum Betrachter eine geeignete Abstraktionsstufe ausgewählt werden. In diesem Beitrag betrachten wir das Problem der Abbildung zwischen kontinuierlichem Maßstab und diskreten generalisierten Modellen und diskutieren Ideen zu Lösungen für den dynamischen Übergang zwischen verschiedenen Generalisierungsstufen eines 3D-Stadtmodells.}, address = {Vienna}, author = {Glander, Tassilo and Baresel, Janett and Döllner, Jürgen}, booktitle = {Tagungsband der 3-Ländertagung DGPF}, howpublished = {CD-Proceedings}, title = {Überlegungen zum stufenlosen Übergang zwischen verschieden generalisierten 3D-Stadtmodellrepräsentationen}, year = 2010 }
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  Out-of-Core Real-Time Visualization of Massive 3D Point Clouds. Richter, Rico; Döllner, Jürgen (2010). 121 - 128.
  [ BibTeX ] [ Details ]
   
  @inproceedings{RD10, abstract = {This paper presents a point-based rendering approach to visualize massive sets of 3D points in real-time. In many disciplines such as architecture, engineering, and archeology LiDAR technology is used to capture sites and landscapes, the resulting massive 3D point clouds pose challenges for traditional storage, processing, and presentation techniques. The available hardware resources of CPU and GPU are limited, and the 3D point cloud data exceeds available memory size in general. Hence out-of-core strategies are required to overcome the limit of memory. We discuss concepts and implementations of rendering algorithms and interaction techniques that make out-of-core real-time visualization and exploration of massive 3D point clouds feasible. We demonstrate with our implementation real-time visualization of arbitrarily sized 3D point clouds with current PC hardware using a spatial data structure in combination with a point-based rendering algorithm. A rendering front is used to increase the performance taking into account user interaction as well as available hardware resources. Furthermore, we evaluate our approach, describe its characteristics, and report on applications.}, author = {Richter, Rico and Döllner, Jürgen}, booktitle = {7th International Conference on Virtual Reality, Computer Graphics, Visualisation and Interaction in Africa}, journal = {7th International Conference on Virtual Reality, Computer Graphics, Visualisation and Interaction in Africa (ACM AFRIGRAPH 2010)}, pages = {121 - 128}, title = {Out-of-Core Real-Time Visualization of Massive 3D Point Clouds}, year = 2010 }
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  Texturierung und Visualisierung virtueller 3D-Stadtmodelle. Technical Report (PhD dissertation), Lorenz, Haik (2010).
  [ BibTeX ] [ Details ]
   
  @phdthesis{Lo10, author = {Lorenz, Haik}, month = 11, school = {HPI, Universität Potsdam}, title = {Texturierung und Visualisierung virtueller 3D-Stadtmodelle}, year = 2010 }
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  Distance Transformations for Accessibility Mapping in the Public Transport Domain: A Performance Assessment. Müller, Matthias; Glander, Tassilo (2010).
  [ BibTeX ] [ Details ]
   
  @inproceedings{MG10, abstract = {In this work, we will conduct an experiment to assess accuracy and computation speed of two distance transformation algorithms, capturing the performance range of state-of-the-art distance transformations for application in public transport scenarios. The first one is a fast but possibly inaccurate modified Euclidean Distance transformation implemented on graphics hardware. The second is a slower but very accurate algorithm realised with the PCRaster library, incorporating road network and additional surface constraints.}, author = {Müller, Matthias and Glander, Tassilo}, booktitle = {CD-Proceedings of GIScience}, month = 9, title = {Distance Transformations for Accessibility Mapping in the Public Transport Domain: A Performance Assessment}, year = 2010 }

2009 [ nach oben ]

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  Interactive Stereo Rendering For Non-Planar Projections of 3D Virtual Environments. Trapp, Matthias; Lorenz, Haik; Döllner, Jürgen (2009). 199--204.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TLD09, abstract = {Stereo rendering, as an additional visual cue for humans, is an important method to increase the immersion into 3D virtual environments. Stereo pairs synthesized for the left and right eye are displayed in a way that the human visual system interprets as 3D perception. Stereoscopy is an emerging field in cinematography and gaming. While generating stereo images is well known for standard projections, the implementation of stereoscopic viewing for non-planar single-center projections, such as cylindrical and spherical projections in real-time, is still a challenge. This paper presents the results of adapting existing image-based and object-based approaches for generating interactive stereoscopic non-planar projections for polygonal scenes on consumer graphics hardware. In particular, it introduces a rendering technique for generating image-based, non-planar stereo pairs within a single rendering pass. Further, this paper presents a comparison between these both approaches with respect to selected criteria.}, author = {Trapp, Matthias and Lorenz, Haik and Döllner, Jürgen}, booktitle = {GRAPP 2009 - 4th International Conference on Computer Graphics Theory and Applications}, pages = {199--204}, publisher = {INSTICC Press}, title = {Interactive Stereo Rendering For Non-Planar Projections of 3D Virtual Environments}, year = 2009 }
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  Real-Time Image Abstraction by Directed Filtering. Kyprianidis, Jan Eric; Döllner, Jürgen in ShaderX7 - Advanced Rendering Techniques, W. Engel (red.) (2009). 285--302.
  [ BibTeX ] [ Details ]
   
  @incollection{KD09, abstract = {In this chapter we present a framework of automatic image processing techniques that create high-quality, simplified, stylistic illustrations from color images, videos, and 3D renderings. Our method extends the approach of [Winnemöller06] to use iterated bilateral filtering for abstraction and difference-of-Gaussians (DoG) for edge detection. We present enhancements to these techniques to improve the quality of the output by adapting them to the local orientation of the input.}, author = {Kyprianidis, Jan Eric and Döllner, Jürgen}, booktitle = {ShaderX7 - Advanced Rendering Techniques}, editor = {Engel, W.}, pages = {285--302}, publisher = {Charles River Media}, title = {Real-Time Image Abstraction by Directed Filtering}, year = 2009 }
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  Sketch-Based Navigation in 3D Virtual Environments. Hagedorn, Benjamin; Döllner, Jürgen in it - Information Technology (2009). (3) 163--170.
  [ BibTeX ] [ Details ]
   
  @article{HD09, abstract = {Navigation represents a fundamental interaction technique for 3D virtual environments (3DVEs) – it enables users to explore the virtual world and to interact with its objects. For this, effective navigation techniques are required that take into account users and their goals. They also should prevent common problems of 3D navigation, such as an intricate camera control or “getting-lost” situations due to incoherent and confusing camera views. Smart navigation aims at this category of navigation techniques, it represents a special type of smart interaction and, thus, an essential element of smart graphics. This article presents the conceptual building blocks of smart navigation for 3DVEs and describes a navigation technique that allows for specifying navigation commands by sketches and gestures: Users sketch their navigation intentions on top of the perspective projection of the 3D scene, the system interprets these sketches regarding the affected scene geometry, as well as the spatial and temporal context. Based on this interpretation, navigation activities are derived and automatically performed. By providing assistance and automation, the smart navigation approach can substantially simplify user interfaces for 3DVEs and, thus, represents an essential component for novel applications of 3DVEs, e.g., based on touch-sensitive displays.}, author = {Hagedorn, Benjamin and Döllner, Jürgen}, journal = {it - Information Technology}, month = 5, number = 3, pages = {163--170}, publisher = {Oldenburger Wissenschaftsverlag}, title = {Sketch-Based Navigation in 3D Virtual Environments}, year = 2009 }
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  Enhancing 3D City Models with Heterogeneous Spatial Information: Towards 3D Land Information Systems. Ross, Lutz; Bolling, Jannes; Döllner, Jürgen; Kleinschmit, Birgit in Lecture Notes in Geoinformation and Cartography, M. Sester, Bernard, L., Paelke, V. (reds.) (2009). 113--133.
  [ BibTeX ] [ Details ]
   
  @inproceedings{RBDK09, abstract = {Spatial and georeferenced information plays an important role in urban land management processes such as spatial planning and environmental management. As many of the processes are increasingly coined by participation of and collaboration between multiple stakeholders, a common medium capable of integrating different types and sources of spatial information is necessary. It is argued that 3D city models provide such a framework and medium into which heterogeneous information can be integrated. Therefore, the main research question of this contribution is to identify and develop methods for integrating heterogeneous spatial and georeferenced information into 3D city models in the context of urban land management. We present a prototype 3D Land Information System and a use case for the city centre of Potsdam, Germany. In addition, constraints within administrations regarding the systematic, sustainable use of such a system are discussed.}, author = {Ross, Lutz and Bolling, Jannes and Döllner, Jürgen and Kleinschmit, Birgit}, booktitle = {12th AGILE International Conference on GI Science}, editor = {Sester, Monika and Bernard, Lars and Paelke, Volker}, pages = {113--133}, publisher = {Springer}, series = {Lecture Notes in Geoinformation and Cartography}, title = {Enhancing 3D City Models with Heterogeneous Spatial Information: Towards 3D Land Information Systems}, year = 2009 }
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  Projecting Code Changes onto Execution Traces to Support Localization of Recently Introduced Bugs. Bohnet, Johannes; Voigt, Stefan; Döllner, Jürgen (2009). 438--442.
  [ BibTeX ] [ Details ]
   
  @inproceedings{BVD09, abstract = {Working collaboratively on complex software systems often leads to situations where a developer enhances or extends system functionality, thereby however, introducing bugs. At best the unintentional changes are caught immediately by regression tests. Often however, the bugs are detected days or weeks later by other developers noticing strange system behavior while working on different parts of the system. Then it is a highly time-consuming task to trace back this behavior change to code changes in the past. In this paper we propose a technique for identifying the recently introduced change that is responsible for the unexpected behavior. The key idea is to combine dynamic, static, and code change information on the system to reduce the possibly great amount of code modifications to those that may affect the system while running its faulty behavior. After having applied this massive automated filtering step, developers receive support in semi-automatically identifying the root cause change by means of a trace exploration frontend. Within multiple synchronized views, developers explore when, how and why modified code locations are executed. The technique is implemented within a prototypical analysis tool that copes with large (> MLOC) C/C++ software systems. We demonstrate the approach by means of industrial case studies.}, author = {Bohnet, Johannes and Voigt, Stefan and Döllner, Jürgen}, booktitle = {24th ACM Symposium on Applied Computing}, pages = {438--442}, publisher = {ACM}, title = {Projecting Code Changes onto Execution Traces to Support Localization of Recently Introduced Bugs}, year = 2009 }
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  Dynamic Mapping of Raster-Data for 3D Geovirtual Environments. Trapp, Matthias; Döllner, Jürgen (2009). 387--392.
  [ BibTeX ] [ Details ]
   
  @inproceedings{TD09, abstract = {Interactive 3D geovirtual environments (GeoVE), such as 3D virtual city and landscape models, are important tools to communicate geospatial information. Usually, this includes static polygonal data (e.g., digital terrain model) and raster data (e.g., aerial images) which are composed from multiple data sources during a complex, only partial automatic pre-processing step. When dealing with highly dynamic geo-referenced raster data, such as the propagation of fires or floods, this pre-processing step hinders the direct application of 3D GeoVE for decision support systems. To compensate for this limitation, this paper presents a concept for dynamically mapping multiple layers of raster for interactive GeoVE. The implementation of our rendering technique is based on the concept of projective texture mapping and can be implemented efficiently using consumer graphics hardware. Further, this paper demonstrates the flexibility of our technique using a number of typical application examples.}, author = {Trapp, Matthias and Döllner, Jürgen}, booktitle = {13th International Conference on IEEE Information Visualisation}, month = 7, pages = {387--392}, publisher = {IEEE Computer Society Press}, title = {Dynamic Mapping of Raster-Data for 3D Geovirtual Environments}, year = 2009 }
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  Approaches Towards Visual 3D Analysis for Digital Landscapes and Its Applications. Engel, Juri; Döllner, Jürgen in Digital Landscape Architecture Proceedings 2009 (2009). 33-41.
  [ BibTeX ] [ Details ]
   
  @article{ED09, abstract = {This contribution outlines approaches towards automatic visual 3D analysis of virtual 3D landscape models. We introduce different notions and definitions of concepts and functions for visual 3D analysis and outline a generic function that determines visual analytic measures among objects of landscape models. This class of functions can be used as a general tool to derive various landscape characteristics and measures on a per-object basis. We also show how these tools can be efficiently implemented to cope with large, complex landscape models. The approach exemplifies how landscape models can be used in the scope of analysis and simulation, which possibly will lead to a class of metrics and characteristics that can be automatically determined and, thereby, may help to systematically characterize and compare landscape plans and concepts.}, author = {Engel, Juri and Döllner, Jürgen}, journal = {Digital Landscape Architecture Proceedings 2009}, pages = {33-41}, publisher = {Anhalt University of Applied Sciences}, title = {Approaches Towards Visual 3D Analysis for Digital Landscapes and Its Applications}, year = 2009 }
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  Towards an indoor level-of-detail model for route visualization. Hagedorn, Benjamin; Trapp, Matthias; Glander, Tassilo; Döllner, Jürgen (2009). 692--697.
  [ BibTeX ] [ Details ]
   
  @inproceedings{hagedorn2009towards, author = {Hagedorn, Benjamin and Trapp, Matthias and Glander, Tassilo and Döllner, Jürgen}, booktitle = {Proceedings of the 2009 Tenth International Conference on Mobile Data Management: Systems, Services and Middleware}, organization = {IEEE}, pages = {692--697}, title = {Towards an indoor level-of-detail model for route visualization}, year = 2009 }
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  Abstract representations for interactive visualization of virtual 3D city models. Glander, Tassilo; Döllner, Jürgen in Computers, Environment and Urban Systems, (P. van Oosterom, red.) (2009). 33(5) 375 -- 387.
  [ BibTeX ] [ URL ] [