TY - CHAP A1 - Brunn, Ansgar A1 - Drauschke, Martin A1 - Kulschewski, Kai A1 - Förstner, Wolfgang T1 - Automatic Dodging of Aerial Images T2 - Publikationen der DGPF, Band 16: Von der Medizintechnik bis zur Planetenforschung - Photogrammetrie und Fernerkundung für das 21. Jahrhundert N2 - We present an automated approach for the dodging of images, with which we edit digital images as it is usually done with analogue images in dark-rooms. Millions of aerial images of all battle fields were taken during the Second World War. They were intensively used, e.g. for the observation of military movements, the documentation of success and failure of military operations and further planning. Today, the information of these images supports the removal of explosives of the Second World War and the identi- fication of dangerous waste in the soil. In North Rhine-Westphalia, approximately 300.000 aerial images are scanned to handle the huge amount of available data efficiently. The scanning is done with a gray value depth of 12 bits and a pixel size of 21 μm to gain both, a high radiometric and a high geometric resolution of the images. Due to the photographic process used in the 1930s and 1940s and several reproductions, the digitized images are exposed locally very differently. Therefore, the images shall be improved by automated dodging. Global approaches mostly returned unsatisfying results. Therefore, we present a new approach, which is based on local histogram equalization. Other methods as spreading the histogram or linear transformations of the histogram manipulate the images either too much or not enough. For the implementation of our approach, we focus not only on the quality of the resulting images, but also on robustness and performance of the algorithm. Thus, the technique can also be used for other applications concerning image improvements. Y1 - 2007 UR - https://www.researchgate.net/publication/242114427_Automatic_Dodging_of_Aerial_Images SP - 173 EP - 180 CY - Muttenz (Schweiz) ER - TY - THES A1 - Brunn, Ansgar T1 - Semantik-basierte Gebäudeerfassung mit verkoppelten Markoff-Zufallsfeldern N2 - In dieser Arbeit wird ein neues automatisches Verfahren zur Erfassung von Gebäuden aus Digitalen Oberflächenmodellen entwickelt. Im Gegensatz zu den meisten bisher in der Literatur beschriebenen Verfahren wird in diesem Ansatz die Rekonstruktion der Gebäude eng mit der Interpretation verknüpft. Es wird ein topologischer Ansatz zur Gebäuderekonstruktion gewählt, der die integrierte Auswertung von unterschiedlichen Datenquellen ermöglicht. Die Topologie eines Objektes lässt sich durch einen CW-Komplex repräsentieren. In dieser Arbeit werden CW-Komplexe zur Repräsentation der Topologie der Gebäudeoberfläche genutzt. Die Bestandteile des CW-Komplexes, die Zellen (Punkte, Kanten und Flächen), werden lokal klassifiziert. Zur Verbesserung der lokalen Klassifikationen werden Nachbarschaftsbedingungen mittels bedingter Wahrscheinlichkeiten berücksichtigt. Dazu wird eine Nachbarschaftsordnung auf dem CW-Komplex definiert und ein verkoppeltes Markoff-Zufallsfeld formuliert. Wir lernen die Gebäudemodelle automatisch aus repräsentativen Interpretationen. Die Gebäude werden lokal -aufgrund der Klassifikation der Zellen - mittels robuster Schätzverfahren rekonstruiert. Die Gebäudetypen der rekonstruierten Gebäude werden durch das Markoff-Zufallsfeld klassifiziert. Zur Veranschaulichung des Potentials und Beurteilung des Verfahrens werden synthetische und reale Beispiele in einem verallgemeinerten geometrischem Modellraum angeführt und diskutiert. N2 - The thesis develops a new automatic algorithm for the acquisition of buildings from digital surface models. In contrast to most of the already published techniques, the new algorithm closely combines the reconstruction with the interpretation. We choose a building representation based on its topology, which enables a combined evalation of different sensor types. We use CW-complexes for the topological building representation. The elements of the CW-complexes, the cells, are classified locally. We take neighborhood relations into account by conditional probabilities to improve the classification result. Therefore we define a neighborhood system on the CW-complex and build a Markov-Random-Field. We automatically learn building models from representative examples. The buildings are reconstructed locally using the classification result. By calculation of various building reconstructions using distinct building modells, a classification of the type of the complete building is done. Establishing a reduced building model, we dicuss synthetic and real examples to show the capabilities of the new algorithm. The importance of the approach is shown by the examples. Y1 - 2001 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:5n-01394 ER - TY - CHAP A1 - Förstner, Wolfgang A1 - Heuel, Stephan A1 - Brunn, Ansgar T1 - Testing Uncertain Geometric Relations T2 - Mustererkennung 2000, Proceedings of the DAGM 2000 in Kiel N2 - This paper integrates statistical reasoning and Grassmann-Cayly algebra for making 2D and 3D geometric reasoning practical. The multi-linearity of the forms allows rigorous error propagation and statistical testing of geometric relations. This is archieved by representing all objects in homogeneous coordinates and expressing all relations using standard matrix calculus. Y1 - 2000 UR - http://www.ipb.uni-bonn.de/pdfs/Forstner2000Statistically.pdf SP - 17 EP - 27 PB - Springer ER - TY - JOUR A1 - Brunn, Ansgar T1 - Analyse von Laserscannerdaten für die Gebäudeextraktion JF - Zeitschrift für Photogrammetrie, Fernerkundung und Geoinformation Y1 - 2000 VL - 3 ER - TY - JOUR A1 - Brunn, Ansgar A1 - Weidner, Uwe T1 - Hierarchical Bayesian Nets for Building Extraction Using Dense Digital Surface Models JF - ISPRS Journal for Photogrammetry & Remote Sensing N2 - During the last years an increasing demand for 3D data of urban scenes can be recognized. Techniques for automatic acquisition of buildings are needed to satisfy this demand in an economic way. This paper describes an approach for building extraction using digital surface models (DSM) as input data. The first task is the detection of areas within the DSM which describe buildings. The second task is the reconstruction of geometric building descriptions. In this paper we focus on new extensions of our approach. The first extension is the detection of buildings using two alternative classification schemes: a binary or a statistical classification based on Bayesian nets, both using local geometric properties. The second extension is the extraction of roof structures as a first step towards the reconstruction of polyhedral building descriptions. Y1 - 1998 U6 - https://doi.org/10.1016/S0924-2716(98)00012-4 VL - 53 IS - 5 SP - 296 EP - 307 ER - TY - JOUR A1 - Brunn, Ansgar A1 - Lang, Felicitas A1 - Gülch, Eberhard A1 - Förstner, Wolfgang T1 - A hybrid concept for 3D building acquisition JF - ISPRS Journal of Photogrammetry and Remote Sensing N2 - This paper presents a hybrid concept of interaction between scene and sensors for image interpretation. We present a strategy for 3D building acquisition which combines different approaches based on different levels of description and different sensors: the detection of regions of interest, and the automatic and semi-automatic reconstruction of object parts and complete buildings. Y1 - 1998 U6 - https://doi.org/10.1016/S0924-2716(97)00039-7 VL - 53 IS - 2 SP - 119 EP - 129 ER - TY - CHAP A1 - Brunn, Ansgar A1 - Lang, Felicitas A1 - Förstner, Wolfgang T1 - A Procedure for Segmenting Surfaces by Symbolic and Iconic Image Fusion T2 - Mustererkennung 96, Proceedings of the DAGM 96 in Heidelberg N2 - This paper deals with the derivation of a symbolic surface description exploiting the information of multiple images while using a minimum of domain knowledge. We present a new concept for segmenting surfaces by fusing multiple images both on the iconic and on the symbolic description level. In a first step a local 3D-reconstruction and interpretation is derived based on the result of a polymorphic feature ex-traction. It serves as prior information for a second step which refines the initial segmentation using the radiometric image content. Examples of the proposed procedure are presented for the application of 3D-building reconstruction from aerial images. Y1 - 1996 U6 - https://doi.org/10.1007/978-3-642-80294-2_2 SP - 11 EP - 20 PB - Springer-Verlag ER - TY - CHAP A1 - Brunn, Ansgar A1 - Weidner, Uwe A1 - Förstner, Wolfgang T1 - Model-based 2D-Shape-Recovery T2 - Mustererkennung 1995, Proceedings of the DAGM 95 in Bielefeld N2 - This paper presents a new approach for the reconstruction of polygons using local and global constraints. THe MDL-based solution is shown to be useful for analysing range and image data of buildungs. Y1 - 1995 UR - http://www.ipb.uni-bonn.de/pdfs/Forstner1995Model.pdf SP - 260 EP - 268 PB - Springer ER - TY - GEN A1 - Brunn, Ansgar T1 - Parameterschätzung in dynamischen Systemen Y1 - 1993 ER - TY - CHAP A1 - Dizbadi, Mehran A1 - Taghipour, Majid A1 - Arastoo, Behrooz A1 - Brunn, Ansgar ED - Ksibi, Prof. Mohamed T1 - Land-use changes in coastal areas of Using Multi-Time satellite data T2 - Euro-Mediterranean Journal for Environmental Integration University of Sfax, Tunisia N2 - The use of coastal lands is constantly changing due to the regression and progress of water 10 areas. This coastal Land use changes the need for continuous monitoring at regular intervals to 11 efficiently manage coastal resources. In this study, the effect of Gorgan gulf ( is location in the 12 southeastern part of the Caspian Sea in Golestan province of IRAN country ) progress and re-13 gression on land-use change in the surrounding lands has been modeled and estimated using 14 remote sensing images. For this purpose, two satellite images of Landsat 5 and Sentinel 2 were 15 taken in 1992 and 2017, respectively, and after preparing and applying the necessary prepro-16 cessing, the most similar classification and land uses of the study area were extracted. Overall 17 accuracy values of 0.94 and kappa coefficient of 0.92 indicated the appropriate accuracy of land 18 use maps. The classified images and the topographic maps, and the network of passages of the 19 study area were designated as land modeling inputs to detect land-use changes over 25 years. The 20 study results showed that the water area of the Gorgan gulf had faced a water level decline of 21 150 square kilometers, which has led to an increase in the area of wastelands. Also, agriculture 22 and garden, and rangelands have been significantly reduced during the study period 23 Keywords: Change Detection, Landsat 5, Sentinel 2, Remote Sensing, Gorgan gulf Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:863-opus-44800 ER - TY - JOUR A1 - Brunn, Ansgar A1 - Degen, Isabella A1 - Weber, Linda A1 - Freibott, Maximilian T1 - 3D-Vermessung der Zoolithenhöhle in der Fränkischen Schweiz - Eine Tropfsteinhöhle virtuell in 3D JF - VDV Magazin - Zeitschrift für Geodäsie und Geoinformatik Y1 - 2014 IS - 1 PB - Chmielorz GmbH CY - Wiesbaden ER - TY - CHAP A1 - Chizhova, Maria A1 - Brunn, Ansgar T1 - Aufbau wissenschaftlicher Partnerschaften nach Osteuropa - ein aktueller Erfahrungsbericht T2 - DGPF-Tagung, Köln, 2015 N2 - Der Aufbau internationaler Partnerschaften nach Osteuropa ist aktuell ein Thema für viele Hochschulen im deutschsprachigen Raum. Gerade die Studiengänge der Vermessung und Geoinformatik haben oftmals Schwierigkeiten Partner im Ausland zu finden, da das Fach in vielen Ländern nicht in der gleichen Form gelehrt wird. Dieser Beitrag zeigt aktuelle Möglichkeiten des Aufbaus von Partnerschaften nach Russland anhand der Erfahrungen der Hochschule für angewandte Wissenschaften Würzburg-Schweinfurt auf. Dazu werden die aktuelle fachspezifische Situation in der Hochschulausbildung wie auch die Struktur der Ausbildung in Russland vorgestellt, kurz mit der Situation an der Hochschule für angewandte Wissenschaften Würzburg-Schweinfurt verglichen sowie die Möglichkeiten der Zusammenarbeit aufgezeigt. Y1 - 2015 UR - http://bvg.fhws.de/fileadmin/FKV/v/studiengang/brunn/p03_DGPF2015_Chizhowa_Brunn.pdf ER - TY - JOUR A1 - Chizhova, Maria A1 - Brunn, Ansgar T1 - ОТ ФОТОСНИМКА К ОБЛАКУ ТОЧЕК: СОЗДАНИЕ 3D-МОДЕЛЕЙ НА ОСНОВЕ ОБЛАКА ТОЧЕК, ПОЛУЧЕННЫХ ФОТОГРАММЕТРИЧЕСКИМ СПОСОБОМ JF - Sammelband der Akademie Iwanowo 2015 T2 - Vom Foto zur Punktwolke: Erstellung von 3D-Modellen auf der Grundlage photogrammetrischer Punktwolken Y1 - 2015 ER - TY - CHAP A1 - Langner, Normen A1 - Brunn, Ansgar A1 - Voellner, David T1 - Drone-based Optimization And Validation Of Numerical Simulations Of Urban Heat Islands T2 - SimBuild 2024 - Eleventh National Conference of IBPSA-USA, Denver, 2024 N2 - In this ongoing research project, advanced drone technology is employed in conjunction with simula-tion models to assess the impacts of urban climate, with a specific focus on Urban Heat Islands (UHI). The novel methodology was tested in the historical downtown areas of two German cities. Through the creation of high-resolution 3D-models of urban structures and the analysis of material properties, the research project aims to accurately predict the cli-mate impacts of urban planning decisions.The results of the project provide planners with pre-cise insights for evaluating adaptation measures and mitigating the adverse effects of climate change in cities, ultimately improving living conditions there-in. The research undertaking also pioneers the use of high-temporal-resolution drone data for analyzing temperature patterns and considers various contribu-tions to the heat island effect for comprehensive climate-adaptive urban planning. Y1 - 2024 UR - https://publications.ibpsa.org/conference/paper/?id=simbuild2024_2132 ER - TY - JOUR A1 - Melnyk, Oleksander A1 - Brunn, Ansgar T1 - Analysis of Spectral Index Interrelationships for Vegetation Condition Assessment on the Example of Wetlands in Volyn Polissya, Ukraine JF - earth N2 - The Cheremskyi Nature Reserve, situated in the Volyn region of Ukraine, constitutes a pivotal element of the European ecological network, distinguished by its distinctive mosaic of peatlands, bogs, and floodplain forests. This study utilizes Sentinel-2 satellite imagery and the Google Earth Engine (GEE) to assess the spatiotemporal patterns of various vegetation indices (NDVI, EVI, SAVI, MSAVI, GNDVI, NDRE, NDWI) from 2017 to 2024. The study aims to select the most suitable combination of vegetation spectral indices for future research. The analysis reveals significant negative trends in NDVI, SAVI, MSAVI, GNDVI, and NDRE, indicating a decline in vegetation health, while NDWI shows a positive trend, suggesting an increased vegetation water content. Correlation analysis underscores robust interrelationships among the indices, with NDVI and SAVI identified as the most significant through random forest feature importance analysis. Principal component analysis (PCA) further elucidates the primary axes of variability, emphasizing the complex interplay between vegetation greenness and moisture content. The findings underscore the utility of multi-index analyses in enhancing predictive capabilities for ecosystem monitoring and support targeted conservation strategies for the sustainable management of the Cheremskyi Nature Reserve. KW - remote sensing KW - sentinel-2 KW - vegetation indices KW - wetlands KW - peatlands KW - ecosystem monitoring Y1 - 2025 UR - https://www.mdpi.com/2673-4834/6/2/28 U6 - https://doi.org/10.3390/earth6020028 VL - 6 IS - 2 ER - TY - CHAP A1 - Melnyk, Oleksandr A1 - Brunn, Ansgar T1 - Seasonal and Long-Term Water Regime Trends of Cheremsky Wetland: Analysis Based on Sentinel-2 Spectral Indices and Composite Indicator Development T2 - Remote Sensing 2025 N2 - Wetlands are critically important ecosystems, but their dynamics, especially in complex regions such as the Ukrainian Polissya, remain poorly understood. This study focuses on the Cheremsky Nature Reserve, an internationally important wetland, to assess long-term (2017–2024) seasonal (spring-summer) trends in water surface conditions. Using Sentinel-2 data and the Google Earth Engine platform, 14 spectral water indices were calculated. Their temporal trends were analyzed using Sen’s method, mutual correlations, and principal component analysis (PCA) to identify the main patterns of variability. Based on the normalized trends and weights obtained from the first two principal components, an integral composite index (CI) for spring and summer seasons was developed. The results revealed seasonal differences in the behavior of the indices and their contribution to the principal components, as well as spatial differentiation of water regime trends within the reserve. The proposed CI allows for an integrated assessment of the long-term dynamics of the wetlands, which is important for the development of conservation and management strategies. KW - remote sensing KW - Sentinel-2 KW - spectral indices KW - composite index KW - Ukrainian Polissya KW - wetland monitoring KW - water surface conditions Y1 - 2025 U6 - https://doi.org/10.3390/rs17142363 VL - 17 IS - 14 ER - TY - JOUR A1 - Brunn, Ansgar T1 - Zwangsfreie Richtungsmessungen T1 - Force-free Angle Measurements JF - zfv – Zeitschrift für Geodäsie, Geoinformation und Landmanagement N2 - Moderne, digitale, automatisierte Tachymeter bieten einen flexiblen Einsatz und erfordern gleichzeitig flexible Rechenverfahren. Einschränkungen der tradierten Auswerteverfahren in Bezug auf die Richtungsmessungen in den Zenit und in Richtung der Nullrichtung (Nullpunkt des Teilkreises) sind dabei nicht akzeptabel. Daher wird in diesem Beitrag ein neuer, auf Richtungsvektoren basierender Umgang mit Richtungsmessungen vorgeschlagen. Der direkte Vergleich des tradierten Verfahrens mit dem neuen Ansatz zeigt das neu gewonnene Potential, letztlich aber auch die Notwendigkeit, das Geodätische Rechnen neu zu erfinden. N2 - Modern, digital, automated total stations offer flexible use and at the same time require flexible calculation methods. Limitations of the traditional evaluation methods with regard to the angle measurements into the zenith and in the zero direction (zero point of the horizontal circle) are not acceptable. Therefore, a new handling of direction measurements based on direction vectors is proposed in this paper. The direct comparison of the traditional method with the new approach shows the newly gained potential, but ultimately also the necessity to reinvent geodetic computing. Y1 - 2024 U6 - https://doi.org/10.12902/zfv-0455-2023 VL - 149 IS - 1 SP - 45 EP - 51 PB - Wißner-Verlag ER - TY - CHAP A1 - Ruppert, Markus A1 - Wörler, Jan A1 - Brunn, Ansgar ED - Ruppert, Markus ED - Wörler, Jan T1 - SketchUp: Modellieren im virtuellen Raum T2 - Technologien im Mathematikunterricht - Eine Sammlung von Trends und Ideen N2 - Das gesellschaftliche Interesse an virtuellen 3D-Darstellungen ist in den letzten Jahren stark gestiegen und reicht längst weit über den Unterhaltungssektor hinaus. Damit einher schreiten auch die technischen Entwicklungen von dreidimensionalen Ein- und Ausgabemöglichkeiten unaufhaltsam fort und die Verfügbarkeit von Laien bedienbarer digitaler Werkzeuge zur virtuellen 3D-Modellierung hat mittlerweile den Freeware-Bereich erreicht. So bietet etwa die Firma Trimble die Software „SketchUp“ zum kostenlosen Download an, mit der u. a. dreidimensionale Modelle realer Gebäude am Rechner umgesetzt und in Google Earth eingebettet werden können. Mit dem Blick auf die Einsatzmöglichkeiten der Softwareprodukte geben die Beiträge geben eine grundlegende Einführung in ihre Bedienung und zeigen auf, wie Gebäudemodelle für die Verwendung mit Google Earth erstellt werden können. Y1 - 2013 SN - 978-3-658-03007-0 SN - 978-3-658-03008-7 U6 - https://doi.org/10.1007/978-3-658-03008-7_5 SP - 135 EP - 156 PB - Springer Spektrum CY - Wiesbaden ER - TY - JOUR A1 - Brunn, Ansgar A1 - Uhl, Anna A1 - Melnyk, Oleksandr A1 - Melnyk, Yuliia A1 - Manko, Pavlo A1 - Fesyuk, Vasyl T1 - Remote sensing monitoring of changes in forest cover in the Volyn region BT - A cross section for the first two decades of the 21st century JF - Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology N2 - This article highlights the significance of forest cover as an important indicator of the state of the environment. It discusses the findings of the Food and Agriculture Organization of the United Nations (FAO) Forest Resources Assessment (FRA) 2020 report, which states that the world's forest area has decreased by 178 million hectares since 1990. The case study of Volyn region shows how cloud processing and vegetation classification can help quantify forest dynamics from 2000 to 2020, allowing local authorities and decision makers to monitor and analyze trends in near real time. Overall, this work provides insights into the importance of monitoring forest dynamics and the potential for remote sensing technology to facilitate this process Y1 - 2024 U6 - https://doi.org/10.26565/2410-7360-2024-60-19 IS - 60 SP - 272 EP - 283 PB - V. N. Karazin Kharkiv National University ER - TY - INPR A1 - Okyere, Franz A1 - Lu, Meng A1 - Brunn, Ansgar T1 - Evaluating the Quality of Open Building Datasets for Mapping Urban Inequality: A Comparative Analysis Across 5 Cities Y1 - 2025 U6 - https://doi.org/10.48550/arXiv.2508.12872 ER - TY - BOOK A1 - Wenzel, Daniela A1 - Brunn, Ansgar T1 - ЗЕМЛЕУСТРОЙСТВО В РАМКАХ ФАКУЛЬТЕТА «МЕЖЕВАНИЕ И ГЕОИНФОРМАТИКА» ИНСТИТУТА ПРИКЛАДНЫХ НАУК ВЮРЦБУРГ–ШВАЙНФУРТ (ГЕРМАНИЯ) T1 - Landmanagement im Studiengang Vermessung und Geoinformatik an der Hochschule für angewandte Wissenschaften Würzburg-Schweinfurt (Deutschland) T3 - Sammelband der Akademie Iwanowo Y1 - 2013 IS - 4 ER -