Browsing by Author "Eisemann, Elmar"

Now showing 1 - 8 of 8
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    Cytosplore: Interactive Visual Single-Cell Profiling of the Immune System
    (The Eurographics Association, 2019) Höllt, Thomas; Pezzotti, Nicola; van Unen, Vincent; Li, Na; Koning, Frits; Eisemann, Elmar; Lelieveldt, Boudewijn P. F.; Vilanova, Anna; Bruckner, Stefan and Oeltze-Jafra, Steffen
    Recent advances in single-cell acquisition technology have led to a shift towards single-cell analysis in many fields of biology. In immunology, detailed knowledge of the cellular composition is of interest, as it can be the cause of deregulated immune responses, which cause diseases. Similarly, vaccination is based on triggering proper immune responses; however, many vaccines are ineffective or only work properly in a subset of those who are vaccinated. Identifying differences in the cellular composition of the immune system in such cases can lead to more precise treatment. Cytosplore is an integrated, interactive visual analysis framework for the exploration of large single-cell datasets. We have developed Cytosplore in close collaboration with immunology researchers and several partners use the software in their daily workflow. Cytosplore enables efficient data analysis and has led to several discoveries alongside high-impact publications.
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    Editing Compressed High-resolution Voxel Scenes with Attributes
    (The Eurographics Association and John Wiley & Sons Ltd., 2023) Molenaar, Mathijs; Eisemann, Elmar; Myszkowski, Karol; Niessner, Matthias
    Sparse Voxel Directed Acyclic Graphs (SVDAGs) are an efficient solution for storing high-resolution voxel geometry. Recently, algorithms for the interactive modification of SVDAGs have been proposed that maintain the compressed geometric representation. Nevertheless, voxel attributes, such as colours, require an uncompressed storage, which can result in high memory usage over the course of the application. The reason is the high cost of existing attribute-compression schemes which remain unfit for interactive applications. In this paper, we introduce two attribute compression methods (lossless and lossy), which enable the interactive editing of compressed high-resolution voxel scenes including attributes.
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    Geometric Sample Reweighting for Monte Carlo Integration
    (The Eurographics Association and John Wiley & Sons Ltd., 2021) Guo, Jerry Jinfeng; Eisemann, Elmar; Zhang, Fang-Lue and Eisemann, Elmar and Singh, Karan
    Numerical integration is fundamental in multiple Monte Carlo rendering problems. We present a sample reweighting scheme, including underlying theory, and analysis of numerical performance for the integration of an unknown one-dimensional function. Our method is simple to implement and builds upon the insight to link the weights to a function reconstruction process during integration. We provide proof that our solution is unbiased in one-dimensional cases and consistent in multi-dimensional cases. We illustrate its effectiveness in several use cases.
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    Interactive Depixelization of Pixel Art through Spring Simulation
    (The Eurographics Association and John Wiley & Sons Ltd., 2023) Matusovic, Marko; Parakkat, Amal Dev; Eisemann, Elmar; Myszkowski, Karol; Niessner, Matthias
    We introduce an approach for converting pixel art into high-quality vector images. While much progress has been made on automatic conversion, there is an inherent ambiguity in pixel art, which can lead to a mismatch with the artist's original intent. Further, there is room for incorporating aesthetic preferences during the conversion. In consequence, this work introduces an interactive framework to enable users to guide the conversion process towards high-quality vector illustrations. A key idea of the method is to cast the conversion process into a spring-system optimization that can be influenced by the user. Hereby, it is possible to resolve various ambiguities that cannot be handled by an automatic algorithm.
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    A Multi-pass Method for Accelerated Spectral Sampling
    (The Eurographics Association and John Wiley & Sons Ltd., 2021) Ruit, Mark van de; Eisemann, Elmar; Zhang, Fang-Lue and Eisemann, Elmar and Singh, Karan
    Spectral Monte Carlo rendering can simulate advanced light phenomena, such as chromatic dispersion, but typically shows a slow convergence behavior. Properly sampling the spectral domain can be challenging in scenes with many complex spectral distributions. To this end, we propose a multi-pass approach. We build and store coarse screen-space estimates of incident spectral radiance and use these to then importance sample the spectral domain. Hereby, we lower variance and reduce noise with little overhead. Our method handles challenging scenarios with difficult spectral distributions, many different emitters, and participating media. Finally, it can be integrated into existing spectral rendering methods for an additional acceleration.
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    Pacific Graphics 2021 - CGF 40-7: Frontmatter
    (The Eurographics Association and John Wiley & Sons Ltd., 2021) Zhang, Fang-Lue; Eisemann, Elmar; Singh, Karan; Zhang, Fang-Lue and Eisemann, Elmar and Singh, Karan
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    A Practical and Efficient Approach for Correct Z-Pass Stencil Shadow Volumes
    (The Eurographics Association, 2019) Usta, Baran; Scandolo, Leonardo; Billeter, Markus; Marroquim, Ricardo; Eisemann, Elmar; Steinberger, Markus and Foley, Tim
    Shadow volumes are a popular technique to compute pixel-accurate hard shadows in 3D scenes. Many variants exist that trade off accuracy and efficiency. In this work, we present an artifact-free, efficient, and easy-to-implement stencil shadow volume method. We compare our method to established stencil shadow volume techniques and show that it outperforms the alternatives.
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    ShutterApp: Spatio-temporal Exposure Control for Videos
    (The Eurographics Association and John Wiley & Sons Ltd., 2019) Salamon, Nestor; Billeter, Markus; Eisemann, Elmar; Lee, Jehee and Theobalt, Christian and Wetzstein, Gordon
    A camera's shutter controls the incoming light that is reaching the camera sensor. Different shutters lead to wildly different results, and are often used as a tool in movies for artistic purpose, e.g., they can indirectly control the effect of motion blur. However, a physical camera is limited to a single shutter setting at any given moment. ShutterApp enables users to define spatio-temporally-varying virtual shutters that go beyond the options available in real-world camera systems. A user provides a sparse set of annotations that define shutter functions at selected locations in key frames. From this input, our solution defines shutter functions for each pixel of the video sequence using a suitable interpolation technique, which are then employed to derive the output video. Our solution performs in real-time on commodity hardware. Hereby, users can explore different options interactively, leading to a new level of expressiveness without having to rely on specialized hardware or laborious editing.