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Application of Nonlinear Feature Normalization on Combined Hyperspectral and Lidar Data

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Application of Nonlinear Feature Normalization on Combined H...

IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)

作者： Wolfgang Gross Dimitri Bulatov Peter Solbrig System Technologies and Image Exploitation (IOSB) Fraunhofer Institute of Optronics Ettlingen Germany

Mitigating nonlinear effects, e.g., due to shadows, variations in illumination conditions, and angular dependencies of spectral signatures is an important topic in hyperspectral remote sensing. In this paper, we apply the Nonlinear Feature Normalization on a combined data set consisting of 128 spectral bands and a weighted digital elevation model. The NFN transforms the data set to a new linear basis and by that mitigates nonlinearities. Evaluation is done by applying the Spectral Angle Mapper to the original and the NFN-transformed data. Different parameter combinations are tested to find the best classification results. Additionally, a Random Forest approach is calculated to compare the results.

关键词： Hyperspectral imaging Training Training data Laser radar Roads Lighting

Digital Ecosystem for FAIR Time Series Data Management in Environmental system Science

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arXiv 2024年

作者： Bumberger, J. Abbrent, M. Brinckmann, N. Hemmen, J. Kunkel, R. Lorenz, C. Lünenschloß, P. Palm, B. Schnicke, T. Schulz, C. van der Schaaf, H. Schäfer, D. Helmholtz Centre for Environmental Research - UFZ Department Monitoring and Exploration Technologies Permoserstraße 15 Leipzig04318 Germany Helmholtz Centre for Environmental Research - UFZ Research Data Management - RDM Permoserstraße 15 Leipzig04318 Germany Halle-Jena-Leipzig Puschstraße 4 LeipzigD-04103 Germany Helmholtz Centre Potsdam - GFZ German Research Centre for Geoscience Department Geoinformation eScience Centre Telegrafenberg Potsdam14473 Germany Wilhelm-Johnen-Straße Jülich52428 Germany Kreuzeckbahnstraße 19 Garmisch-Partenkirchen82467 Germany Helmholtz Centre for Environmental Research - UFZ IT Department Permoserstraße 15 Leipzig04318 Germany Fraunhofer Institute of Optronics System Technologies and Image Exploitation IOSB Fraunhoferstraße 1 Karlsruhe76131 Germany

Addressing the challenges posed by climate change, biodiversity loss, and environmental pollution requires comprehensive monitoring and effective data management strategies that are applicable across various scales in environmental system science. This paper introduces a versatile and transferable digital ecosystem for managing time series data, designed to adhere to the FAIR principles (Findable, Accessible, Interoperable, and Reusable). The system is highly adaptable, cloud-ready, and suitable for deployment in a wide range of settings, from small-scale projects to large-scale monitoring initiatives. The ecosystem comprises three core components: the Sensor Management system (SMS) for detailed metadata registration and management;***, a platform for efficient time series data storage, transfer, and real-time visualization;and the system for Automated Quality Control (SaQC), which ensures data integrity through real-time analysis and quality assurance. The modular architecture, combined with standardized protocols and interfaces, ensures that the ecosystem can be easily transferred and deployed across different environments and institutions. This approach enhances data accessibility for a broad spectrum of stakeholders, including researchers, policymakers, and the public, while fostering collaboration and advancing scientific research in environmental monitoring. © 2024, CC BY-SA.

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Application range of crosstalk-affected spatial demultiplexing for resolving separations between unbalanced sources

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arXiv 2022年

作者： Linowski, Tomasz Schlichtholz, Konrad Sorelli, Giacomo Gessner, Manuel Walschaers, Mattia Treps, Nicolas Rudnicki, Lukasz International Centre for Theory of Quantum Technologies University of Gdansk Gdańsk80-308 Poland Laboratoire Kastler Brossel Sorbonne Université ENS-Université PSL CNRS Collège de France 4 Place Jussieu Paris75252 France Fraunhofer IOSB Ettlingen Fraunhofer Institute of Optronics System Technologies and Image Exploitation Gutleuthausstr. 1 Ettlingen76275 Germany Departamento de Física Teórica and IFIC Universidad de Valencia-CSIC C/ Dr. Moliner 50 Valencia Burjassot46100 Spain Center for Theoretical Physics Polish Academy of Sciences Warszawa02-668 Poland

Superresolution is one of the key issues at the crossroads of contemporary quantum optics and metrology. Recently, it was shown that for an idealized case of two balanced sources, spatial mode demultiplexing (SPADE) achieves resolution better than direct imaging even in the presence of measurement crosstalk [Phys. Rev. Lett. 125, 100501 (2020)]. In this work, we consider arbitrarily unbalanced sources and provide a systematic analysis of the impact of crosstalk on the resolution obtained from SPADE. As we dissect, in this generalized scenario, SPADE’s effectiveness depends non-trivially on the strength of crosstalk, relative brightness and the separation between the sources. In particular, for any source imbalance, SPADE performs worse than ideal direct imaging in the asymptotic limit of vanishing source separations. Nonetheless, for realistic values of crosstalk strength, SPADE is still the superior method for several orders of magnitude of source separations. Copyright © 2022, The Authors. All rights reserved.

关键词： Demultiplexing

Improving feature-based visual SLAM in Person Indoor Navigation with HDR Imaging

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Improving feature-based visual SLAM in Person Indoor Navigat...

IEEE International Conference on Information Communication and Signal Processing (ICICSP)

作者： Alexander Albrecht Nina Felicitas Heide Systems for Measurement Control and Diagnosis Fraunhofer Institute of Optronics System Technologies and Image Exploitation IOSB Karlsruhe Germany

Drastically changing illumination conditions and high dynamic ranges lead to over- and underexposed image areas, which challenge feature detection. As a result the quality of feature-based visual Simultaneous Localization and Mapping (SLAM) suffers. This work addresses the problem by using High Dynamic Ranging (HDR) image data as visual input. Utilizing HDR cameras with two prism-mounted CCDs allows fusion of two synchronized video streams. This paper analyzes various HDR fusion methods focusing on the suitability for feature-based visual SLAM. The fusion methods are evaluated on a person carried HDR stereo camera system under realistic indoor application scenarios. Changes of illumination are provoked by cameras facing windows with bright luminance. It has been demonstrated, that our method is capable of handling changing illumination conditions, which results in a more stable and reliable visual SLAM solution.

关键词： Cameras Visualization Simultaneous localization and mapping Lighting Feature extraction image fusion Indoor navigation

Ontology Population Framework of MAGNETO for Instantiating Heterogeneous Forensic Data Modalities 15th

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Ontology Population Framework of MAGNETO for Instantiating H...

15th IFIP WG 12.5 International Conference on Artificial Intelligence Applications and Innovations, AIAI 2019

作者： Behmer, Ernst-Josef Chandramouli, Krishna Garrido, Victor Mühlenberg, Dirk Müller, Dennis Müller, Wilmuth Pallmer, Dirk Pérez, Francisco J. Piatrik, Tomas Â Vargas, Camilo Fraunhofer Institute for Optronics System Technologies and Image Exploitation IOSB Karlsruhe Germany Venaka Media Limited London United Kingdom Universitat Politècnica de València Valencia Spain Queen Mary University of London London United Kingdom

ISBN: (纸本)9783030198220

The growth in digital technologies has influenced three characteristics of information namely the volume, the modality and the frequency. As the amount of information generated by individuals increases, there is a critical need for the Law Enforcement Agencies to exploit all available resources to effectively carry out criminal investigation. Addressing the increasing challenges in handling the large amount of diversified media modalities generated at high-frequency, the paper outlines a systematic approach adopted for the processing and extraction of semantic concepts formalized to assist criminal investigations. The novelty of the proposed framework relies on the semantic processing of heterogeneous data sources including audio-visual footage, speech-to-text, text mining, suspect tracking and identification using distinctive region or pattern. Information extraction from textual data, machine-translated into English from various European languages, uses semantic role labeling. All extracted information is stored in one unifying system based on an ontology developed specifically for this task. The described technologies will be implemented in the Multimedia Analysis and correlation enGine for orgaNised crime prEvention and invesTigatiOn (MAGNETO). © 2019, IFIP International Federation for Information Processing.

关键词： Semantics

Generating infinitely long phase-screens with the Karhunen-Loève decomposition

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Generating infinitely long phase-screens with the Karhunen-L...

3D image Acquisition and Display: Technology, Perception and Applications, 3D 2018

作者： Gladysz, Szymon Anzuola, Esdras Fraunhofer Institute of Optronics System Technologies and Image Exploitation Gutleuthausstr. 1 Ettlingen76275 Germany

ISBN: (纸本)9781943580446

We introduce a method for creating temporally evolving wavefront distortions that uses Karhunen-Loève decomposition and the associated temporal power spectra. We demonstrate that the method is able to produce dynamic wavefronts that follow the behavior predicted by the theory while introducing key advantages in terms of calculation speed and storage in computer memory. © 2018 The Author(s).

关键词： Wavefronts

Correction of atmospheric effects on laser beams for sensing and communication

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Correction of atmospheric effects on laser beams for sensing...

Applications of Lasers for Sensing and Free Space Communications, LSC 2018

作者： Stein, Karin Fraunhofer Institute of Optronics System Technologies and Image Exploitation Gutleuthausstr. 1 Ettlingen76275 Germany

ISBN: (纸本)9781943580446

Environmental effects limit the performance of any electro-optical (EO) system. Tasks such as delivery of directed energy and laser communications are significantly affected by atmospheric turbulence and refraction. A correction of atmospheric effects on the propagation of light can be done by adaptive optics (AO). Nevertheless, challenging scenarios like strong turbulence near the ground lead to high failure rates of the traditional adaptive optics systems. Unconventional wavefront sensors and sensing strategies are developed at fraunhofer IOSB to provide alternatives for measuring the wavefront deformation of a laser beam and to improve the performance of energy delivery and laser communications applications even in strong turbulence and/or horizontal- or slant-path propagation. © 2018 The Author(s).

关键词： Laser beams

Fusion of time of arrival and time difference of arrival for ultra-wideband indoor localization

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arXiv 2019年

作者： Sidorenko, Juri Schatz, Volker Scherer-Negenborn, Norbert Arens, Michael Hugentobler, Urs Fraunhofer Institute of Optronics System Technologies and Image Exploitation IOSB Germany Institute of Astronomical and Physical Geodesy Technical University of Munich Germany

This article presents a new approach for the wireless clock synchronization of Decawave ultra-wideband transceivers based on the time difference of arrival. The presented techniques combine the time-of-arrival and time-difference-of-arrival measurements without losing the advantages of each approach. The precision and accuracy of the distances measured by the Decawave devices depends on three effects: signal power, clock drift, and uncertainty in the hardware delay. This article shows how all three effects may be compensated with both measurement techniques. Copyright © 2019, The Authors. All rights reserved.

关键词： Time difference of arrival

Decawave UWB clock drift correction and power self-calibration

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arXiv 2019年

The position accuracy based on Decawave Ultra-Wideband (UWB) is affected mainly by three factors: hardware delays, clock drift, and signal power. This article discusses the last two factors. The general approach to clock drift correction uses the phase-locked loop (PLL) integrator, which we show is subject to signal power variations, and therefore, is less suitable for clock drift correction. The general approach to the estimation of signal power correction curves requires additional measurement equipment. This article presents a new method for obtaining the curve without additional hardware and clock drift correction without the PLL integrator. Both correction methods were fused together to improve two-way ranging (TWR). Copyright © 2019, The Authors. All rights reserved.

关键词： Time of arrival