Dissertations / Theses: 'Digitale Photogrammetrie'

1

Hampel, Uwe. "Photogrammetrische Erfassung der Verformungs- und Rissentwicklung bei baumechanischen Untersuchungen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1213691909563-21395.

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Abstract:

Verfahren der digitalen Nahbereichsphotogrammetrie ermöglichen eine dreidimensionale Erfassung von Objekten und stellen damit interessante Lösungsansätze für Messaufgaben im Bautechnischen Mess- und Versuchswesen dar. Ihr Einsatz bietet bei einer Vielzahl baumechanischer Untersuchungen die Voraussetzung für eine kontinuierliche, zeitsynchrone Objektoberflächenerfassung bei kurz- und langzeitigen Belastungsversuchen im Labor und in situ. Die daraus resultierenden Möglichkeiten der kontinuierlichen Erfassung von Verformungs-, Riss- und Schädigungsentwicklungen an Objektoberflächen stellen für viele experimentelle Untersuchungen im Bauingenieurwesen eine signifikante Qualitätssteigerung dar, die mit klassischen Messtechniken – wie z. B. Dehnmessstreifen oder induktiven Wegaufnehmern – nur bedingt bzw. nicht realisiert werden kann. Um das Potential der digitalen Nahbereichsphotogrammetrie zur kontinuierlichen Erfassung der Verformungs-, Riss- und Schädigungsentwicklung an Objektoberflächen bei baumechanischen Untersuchungen erfassen zu können, wurden – aufbauend auf den bekannten Grundlagen und Lösungsansätzen – systematische Untersuchungen durchgeführt. Diese bildeten den Ausgangspunkt für den Einsatz photogrammetrischer Verfahren bei experimentellen Untersuchungen in den verschiedenen Teildisziplinen des Bauingenieurwesens, z. B. im Holz-, Massiv-, Mauerwerks-, Stahl- und Straßenbau. Die photogrammetrisch zu erfassenden Versuchsobjekte – einschließlich ihrer Veränderungen bei den Belastungsversuchen – waren dabei u. a. kleinformatige Prüfkörper und Baukonstruktionen aus den verschiedensten Materialien bzw. Verbundmaterialien. Bei den anwendungsorientierten Untersuchungen musste beachtet werden, dass aufgrund der z. T. sehr heterogenen Anforderungen und der zahlreichen Möglichkeiten, die beim Einsatz photogrammetrischer Verfahren denkbar waren, die Notwendigkeit der Auswahl und ggf. einer Weiter- bzw. Neuentwicklung geeigneter Systeme, effizienter Verfahren und optimaler Auswertealgorithmen der digitalen Nahbereichsphotogrammetrie bestand. In diesem Zusammenhang wurde mit der systematischen Zusammenstellung und Untersuchung relevanter Einflussgrößen begonnen. Diese waren oftmals durch die jeweiligen photogrammetrischen Messprozesse und Messaufgaben beeinflusst. Die Ergebnisse machen deutlich, dass die digitale Nahbereichsphotogrammetrie ein flexibel anwendbares Werkzeug für die Erfassung der Verformungs-, Riss- und Schädigungsentwicklung bei baumechanischen Untersuchungen darstellt. Spezielle Messaufgaben stellen im Bautechnischen Mess- und Versuchswesen oftmals sehr hohe Anforderungen an die Messgenauigkeit, die Robustheit und das Messvolumen. Sie erfordern optimierte Verfahren und führten im Zusammenhang mit der vorliegenden Arbeit zu einer Reihe von Lösungen, wie beispielsweise der 2.5D-Objekterfassung auf Basis der Dynamischen Projektiven Transformation oder der Objekterfassung mittels Spiegelphotogrammetrie. Im Hinblick auf die Objektsignalisierung wurde eine intensitätsbasierte Messmarke entwickelt. Diese ermöglicht besonders bei sehr hochgenauen Deformations- bzw. Dehnungsmessungen ein großes Genauigkeitspotential im Sub-Pixelbereich, das im 1/100 eines Pixels liegt. In Bezug auf die photogrammetrischen Auswerteprozesse wurden optimierte Bildzuordnungsverfahren implementiert, die beispielsweise eine Punkteinmessung von bis zu 60.000 Punkten pro Sekunde ermöglichen und eine Grundlage für die flächenhafte Rissanalyse darstellen. In Bezug auf die qualitative und quantitative Risserfassung wurden verschiedene Verfahren entwickelt. Diese ermöglichen z. B. die lastabhängige Erfassung der Rissposition und -breite in Messprofilen. In einem Messbereich von 100 mm x 100 mm konnten beispielsweise Verformungen mit einer Genauigkeit bis 1 µm und Rissbreiten ab 3 µm erfasst werden. Im Zusammenhang mit den zahlreichen anwendungsbezogenen Untersuchungen entstanden immer wieder Fragen hinsichtlich der Faktoren, die einen Einfluss auf den photogrammetrischen Messprozess im Bautechnischen Mess- und Versuchswesen ausüben. Aufgrund der zahlreichen Einflussgrößen, die als Steuer- bzw. Störgrößen eine mögliche Wirkung auf bauspezifische photogrammetrische Messprozesse ausüben können, wurde im Rahmen der vorliegenden Arbeit mit deren systematischer Zusammenstellung relevanter Einflussgrößen begonnen. Die Relevanz einzelner Einflussgrößen konnte durch Untersuchungen bereits bestätigt werden. Um eine ganzheitliche Bewertung aller relevanten Einflussgrößen aufgabenabhängig vornehmen zu können, wurde ein spezieller Versuchsstand entwickelt. Dieser ermöglicht eine vollautomatisierte systematische Untersuchung bauspezifischer photogrammetrischer Messprozesse unter definierten Versuchsbedingungen und dient dem systematischen Einsatz photogrammetrischer Verfahren im Bautechnischen Mess- und Versuchswesen hinsichtlich der Absicherung bestehender Messaufgaben, kann aber auch zu weiteren neuen und optimierten Messprozessen führen
Methods of digital close range photogrammetry are a useful tool for the measurement of three-dimensional objects in civil engineering material testing. They are generally suitable for automatic measurements with chronological synchronism of object-surfaces during short and long time load tests in laboratories and in situ. The methods provide an opportunity for measuring deformations, cracks and damages at the object-surfaces during load tests in civil engineering material testing. These possibilities can present new results for a lot of applications in civil engineering material testing. Displacement and deformation measurements still rely on wire strain gauges or inductive displacement transducers. However, they are not suitable for a large number of measurement points or the detection of cracks during load tests. First of all, a number of systematic investigations was conducted. This was necessary to identify capable methods of the digital photogrammetry for the measuring of deformations, cracks and damages at object-surfaces during load tests in civil engineering material testing. These investigations laid the foundation for practical measurements during short and long time load tests of samples and constructions from different parts of the civil engineering (e.g. timber construction, solid structure, stell and road construction). The application-oriented research in civil engineering material testing demonstrates the wide range of demands on systems and methods of digital close range photogrammetry have to meet. Often the methods and systems of digital close range photogrammetry had to be modified or developed. In this context the systematic analysis of relevant determining factors was started.The results demonstrate that the methods and systems of digital close range photogrammetry are a suitable and flexible tool for the measurement of deformations, cracks and damages at the object-surfaces in civil engineering material testing. In addition, the special experiments in civil engineering material testing demonstrate the high requirements laid upon methods and systems of the digital closed range photogrammetry, for instance regarding with the measurement resolution/range and robustness processes. This was the motivation to optimize and to develop methods and systems for the special measurement tasks in civil engineering material testing, for instance a 2.5D measurement technique based on the Dynamic Projective Transformation (DPT) or the use of mirrors. Also a special measurement target was developed. This type of measurement target modifies intensities and is ideal for high deformation measurements (1/100 pixel). The large number of points in conjunction with area-based measurements require time-optimized methods for the analysis process. The modified and developed methods/programs enable fast analysis-processes, e.g. in conjunction with point-matching process 60.000 points per second.The developed crack-detection-methods allow area- and profile-based to analyze the load-dependent position and width of cracks, e.g. cracks > 3 µm (100 mm x 100 mm). A main target of this work was to compile all relevant determining factors regarding the application of the digital close range photogrammetry during load tests in civil engineering material testing. To a large extent, this target was reached. However, the compilation of all relevant determining factors requires a special experimental set-up. This experimental set-up was developed. In the future, it may enable the automatic research of all significant determining factors. The results can be used to qualify or optimize the established methods and processes. Also it's possible that the results generates new measurement processes

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2

Hampel, Uwe. "Photogrammetrische Erfassung der Verformungs- und Rissentwicklung bei baumechanischen Untersuchungen." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A23829.

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Abstract:

Verfahren der digitalen Nahbereichsphotogrammetrie ermöglichen eine dreidimensionale Erfassung von Objekten und stellen damit interessante Lösungsansätze für Messaufgaben im Bautechnischen Mess- und Versuchswesen dar. Ihr Einsatz bietet bei einer Vielzahl baumechanischer Untersuchungen die Voraussetzung für eine kontinuierliche, zeitsynchrone Objektoberflächenerfassung bei kurz- und langzeitigen Belastungsversuchen im Labor und in situ. Die daraus resultierenden Möglichkeiten der kontinuierlichen Erfassung von Verformungs-, Riss- und Schädigungsentwicklungen an Objektoberflächen stellen für viele experimentelle Untersuchungen im Bauingenieurwesen eine signifikante Qualitätssteigerung dar, die mit klassischen Messtechniken – wie z. B. Dehnmessstreifen oder induktiven Wegaufnehmern – nur bedingt bzw. nicht realisiert werden kann. Um das Potential der digitalen Nahbereichsphotogrammetrie zur kontinuierlichen Erfassung der Verformungs-, Riss- und Schädigungsentwicklung an Objektoberflächen bei baumechanischen Untersuchungen erfassen zu können, wurden – aufbauend auf den bekannten Grundlagen und Lösungsansätzen – systematische Untersuchungen durchgeführt. Diese bildeten den Ausgangspunkt für den Einsatz photogrammetrischer Verfahren bei experimentellen Untersuchungen in den verschiedenen Teildisziplinen des Bauingenieurwesens, z. B. im Holz-, Massiv-, Mauerwerks-, Stahl- und Straßenbau. Die photogrammetrisch zu erfassenden Versuchsobjekte – einschließlich ihrer Veränderungen bei den Belastungsversuchen – waren dabei u. a. kleinformatige Prüfkörper und Baukonstruktionen aus den verschiedensten Materialien bzw. Verbundmaterialien. Bei den anwendungsorientierten Untersuchungen musste beachtet werden, dass aufgrund der z. T. sehr heterogenen Anforderungen und der zahlreichen Möglichkeiten, die beim Einsatz photogrammetrischer Verfahren denkbar waren, die Notwendigkeit der Auswahl und ggf. einer Weiter- bzw. Neuentwicklung geeigneter Systeme, effizienter Verfahren und optimaler Auswertealgorithmen der digitalen Nahbereichsphotogrammetrie bestand. In diesem Zusammenhang wurde mit der systematischen Zusammenstellung und Untersuchung relevanter Einflussgrößen begonnen. Diese waren oftmals durch die jeweiligen photogrammetrischen Messprozesse und Messaufgaben beeinflusst. Die Ergebnisse machen deutlich, dass die digitale Nahbereichsphotogrammetrie ein flexibel anwendbares Werkzeug für die Erfassung der Verformungs-, Riss- und Schädigungsentwicklung bei baumechanischen Untersuchungen darstellt. Spezielle Messaufgaben stellen im Bautechnischen Mess- und Versuchswesen oftmals sehr hohe Anforderungen an die Messgenauigkeit, die Robustheit und das Messvolumen. Sie erfordern optimierte Verfahren und führten im Zusammenhang mit der vorliegenden Arbeit zu einer Reihe von Lösungen, wie beispielsweise der 2.5D-Objekterfassung auf Basis der Dynamischen Projektiven Transformation oder der Objekterfassung mittels Spiegelphotogrammetrie. Im Hinblick auf die Objektsignalisierung wurde eine intensitätsbasierte Messmarke entwickelt. Diese ermöglicht besonders bei sehr hochgenauen Deformations- bzw. Dehnungsmessungen ein großes Genauigkeitspotential im Sub-Pixelbereich, das im 1/100 eines Pixels liegt. In Bezug auf die photogrammetrischen Auswerteprozesse wurden optimierte Bildzuordnungsverfahren implementiert, die beispielsweise eine Punkteinmessung von bis zu 60.000 Punkten pro Sekunde ermöglichen und eine Grundlage für die flächenhafte Rissanalyse darstellen. In Bezug auf die qualitative und quantitative Risserfassung wurden verschiedene Verfahren entwickelt. Diese ermöglichen z. B. die lastabhängige Erfassung der Rissposition und -breite in Messprofilen. In einem Messbereich von 100 mm x 100 mm konnten beispielsweise Verformungen mit einer Genauigkeit bis 1 µm und Rissbreiten ab 3 µm erfasst werden. Im Zusammenhang mit den zahlreichen anwendungsbezogenen Untersuchungen entstanden immer wieder Fragen hinsichtlich der Faktoren, die einen Einfluss auf den photogrammetrischen Messprozess im Bautechnischen Mess- und Versuchswesen ausüben. Aufgrund der zahlreichen Einflussgrößen, die als Steuer- bzw. Störgrößen eine mögliche Wirkung auf bauspezifische photogrammetrische Messprozesse ausüben können, wurde im Rahmen der vorliegenden Arbeit mit deren systematischer Zusammenstellung relevanter Einflussgrößen begonnen. Die Relevanz einzelner Einflussgrößen konnte durch Untersuchungen bereits bestätigt werden. Um eine ganzheitliche Bewertung aller relevanten Einflussgrößen aufgabenabhängig vornehmen zu können, wurde ein spezieller Versuchsstand entwickelt. Dieser ermöglicht eine vollautomatisierte systematische Untersuchung bauspezifischer photogrammetrischer Messprozesse unter definierten Versuchsbedingungen und dient dem systematischen Einsatz photogrammetrischer Verfahren im Bautechnischen Mess- und Versuchswesen hinsichtlich der Absicherung bestehender Messaufgaben, kann aber auch zu weiteren neuen und optimierten Messprozessen führen.
Methods of digital close range photogrammetry are a useful tool for the measurement of three-dimensional objects in civil engineering material testing. They are generally suitable for automatic measurements with chronological synchronism of object-surfaces during short and long time load tests in laboratories and in situ. The methods provide an opportunity for measuring deformations, cracks and damages at the object-surfaces during load tests in civil engineering material testing. These possibilities can present new results for a lot of applications in civil engineering material testing. Displacement and deformation measurements still rely on wire strain gauges or inductive displacement transducers. However, they are not suitable for a large number of measurement points or the detection of cracks during load tests. First of all, a number of systematic investigations was conducted. This was necessary to identify capable methods of the digital photogrammetry for the measuring of deformations, cracks and damages at object-surfaces during load tests in civil engineering material testing. These investigations laid the foundation for practical measurements during short and long time load tests of samples and constructions from different parts of the civil engineering (e.g. timber construction, solid structure, stell and road construction). The application-oriented research in civil engineering material testing demonstrates the wide range of demands on systems and methods of digital close range photogrammetry have to meet. Often the methods and systems of digital close range photogrammetry had to be modified or developed. In this context the systematic analysis of relevant determining factors was started.The results demonstrate that the methods and systems of digital close range photogrammetry are a suitable and flexible tool for the measurement of deformations, cracks and damages at the object-surfaces in civil engineering material testing. In addition, the special experiments in civil engineering material testing demonstrate the high requirements laid upon methods and systems of the digital closed range photogrammetry, for instance regarding with the measurement resolution/range and robustness processes. This was the motivation to optimize and to develop methods and systems for the special measurement tasks in civil engineering material testing, for instance a 2.5D measurement technique based on the Dynamic Projective Transformation (DPT) or the use of mirrors. Also a special measurement target was developed. This type of measurement target modifies intensities and is ideal for high deformation measurements (1/100 pixel). The large number of points in conjunction with area-based measurements require time-optimized methods for the analysis process. The modified and developed methods/programs enable fast analysis-processes, e.g. in conjunction with point-matching process 60.000 points per second.The developed crack-detection-methods allow area- and profile-based to analyze the load-dependent position and width of cracks, e.g. cracks > 3 µm (100 mm x 100 mm). A main target of this work was to compile all relevant determining factors regarding the application of the digital close range photogrammetry during load tests in civil engineering material testing. To a large extent, this target was reached. However, the compilation of all relevant determining factors requires a special experimental set-up. This experimental set-up was developed. In the future, it may enable the automatic research of all significant determining factors. The results can be used to qualify or optimize the established methods and processes. Also it's possible that the results generates new measurement processes.

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3

Eilermann, Frank. "Beiträge zum Aufbau eines forstlichen Geographischen Informationssystems unter besonderer Berücksichtigung der Integration der digitalen Photogrammetrie - dargestellt am Beispiel der Entwicklung von Entscheidungshilfen für einen ökologisch begründeten Waldumbau." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2003. http://nbn-resolving.de/urn:nbn:de:swb:14-1040304585218-28204.

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Für einen ökologischen Waldumbau sind naturwissenschaftliche und ökonomische Grundlagen erforderlich, um die Entscheidungsträger unterstützen. Die Problematik des Waldumbaus bei heterogenen Bedingungen des Osterzgebirges setzt ein flächenbezogenes Informationsmanagement voraus. Durch Aufbau eines forstökologischen Informationssystems werden naturwissenschaftliche und forstbetriebliche Grunddaten auf räumliche Einheiten übertragen und damit Entscheidungshilfen. Zur Erzielung standortsgerechter, stabiler und leistungsfähiger Mischbestände müssen unter Berücksichtigung waldbaulicher und ertragskundlicher Verhältnisse waldbauliche Strategien aufgezeigt und deren mittelfristige Umsetzung geplant werden. Zur Gestaltung des Planungskonzepts werden ausgehend vom IST-Zustand geeignete Maßnahmen zum Erreichen eines SOLL-Zustands aufgezeigt. Instrumentelle Basis bildet ein Forstökologisches Informationssystem, dessen GIS-Funktionalitäten flächenbezogene Entscheidungshilfen durch vielschichtige Datenanalyse ermöglichen. Die Auswertung von analogen und digitalen Luftbildern mit verschiedenen Stichprobenverfahren werden kombiniert. Mit einem Kalkulationsprogramm werden Bewirtschaftungsmaßnahmen hinsichtlich zu erwartender Kosten und Erlöse charakterisiert. Durch das Informationssystems lassen sich die naturwissenschaftlichen und forstbetrieblichen Grunddaten auf räumliche Einheiten übertragen. Planungsvorschläge zum Waldumbau in Form von Entscheidungshilfen stehen zur Verfügung. Die Integration auf Intensivmeßflächen gewonnener Daten ins Informationssystem und Übertragung auf flächige Bezugseinheiten gewährleisten die Beachtung vielfältiger Ursache-Wirkungsbeziehungen zur forstbetrieblichen Planung. Für die verschiedenen Höhenstufen werden spezifische waldbauliche Behandlungsvarianten durch Entscheidungsmodelle abgebildet, die eine flächenbezogene Umsetzung ermöglichen.

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4

Eilermann, Frank. "Beiträge zum Aufbau eines forstlichen Geographischen Informationssystems unter besonderer Berücksichtigung der Integration der digitalen Photogrammetrie - dargestellt am Beispiel der Entwicklung von Entscheidungshilfen für einen ökologisch begründeten Waldumbau." Doctoral thesis, Technische Universität Dresden, 2002. https://tud.qucosa.de/id/qucosa%3A23964.

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Abstract:

Für einen ökologischen Waldumbau sind naturwissenschaftliche und ökonomische Grundlagen erforderlich, um die Entscheidungsträger unterstützen. Die Problematik des Waldumbaus bei heterogenen Bedingungen des Osterzgebirges setzt ein flächenbezogenes Informationsmanagement voraus. Durch Aufbau eines forstökologischen Informationssystems werden naturwissenschaftliche und forstbetriebliche Grunddaten auf räumliche Einheiten übertragen und damit Entscheidungshilfen. Zur Erzielung standortsgerechter, stabiler und leistungsfähiger Mischbestände müssen unter Berücksichtigung waldbaulicher und ertragskundlicher Verhältnisse waldbauliche Strategien aufgezeigt und deren mittelfristige Umsetzung geplant werden. Zur Gestaltung des Planungskonzepts werden ausgehend vom IST-Zustand geeignete Maßnahmen zum Erreichen eines SOLL-Zustands aufgezeigt. Instrumentelle Basis bildet ein Forstökologisches Informationssystem, dessen GIS-Funktionalitäten flächenbezogene Entscheidungshilfen durch vielschichtige Datenanalyse ermöglichen. Die Auswertung von analogen und digitalen Luftbildern mit verschiedenen Stichprobenverfahren werden kombiniert. Mit einem Kalkulationsprogramm werden Bewirtschaftungsmaßnahmen hinsichtlich zu erwartender Kosten und Erlöse charakterisiert. Durch das Informationssystems lassen sich die naturwissenschaftlichen und forstbetrieblichen Grunddaten auf räumliche Einheiten übertragen. Planungsvorschläge zum Waldumbau in Form von Entscheidungshilfen stehen zur Verfügung. Die Integration auf Intensivmeßflächen gewonnener Daten ins Informationssystem und Übertragung auf flächige Bezugseinheiten gewährleisten die Beachtung vielfältiger Ursache-Wirkungsbeziehungen zur forstbetrieblichen Planung. Für die verschiedenen Höhenstufen werden spezifische waldbauliche Behandlungsvarianten durch Entscheidungsmodelle abgebildet, die eine flächenbezogene Umsetzung ermöglichen.

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5

Masaad, Elshami M. "Close-range photogrammetry based on digital imagery analysis : real-time photogrammetric measurements from video imagery." Thesis, University of Manchester, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338480.

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Smith, Douglas G. "Digital photogrammetry for elevation modelling." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362992.

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7

Li, Xiaopeng. "Photogrammetric investigation into low-resolution digital camera systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0016/NQ46296.pdf.

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8

Adler, Petra. "Einsatz digitaler Photogrammetrie zur Beschreibung von Waldbeständen - am Beispiel der digitalen photogrammetrischen Erfassung der Level-2-Flächen Baden-Württembergs." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963868454.

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Tseng, Yi-Hsing. "Digital photogrammetric approach to ice-flow determination in Antarctica /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487779439846091.

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Smit, Julian Lloyd. "Three dimensional measurement of textured surfaces using digital photogrammetric techniques." Doctoral thesis, University of Cape Town, 1997. http://hdl.handle.net/11427/16087.

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Bibliography: pages 133-156.
The deep-level gold mines on the Witwatersrand (South Africa) are located at depths of over 3,000m below surface. Mining excavations follow tabular reefs that are kilometres in extent, but only a few centimetres thick. Due to the great depths of these excavations and the large overburden of rock, immense pressure is exerted on the rock mass being excavated. In order to relieve this stress in the rock mass being mined, the rock is "pre-conditioned" by pre-fracturing the rock face with large blasts. This has the effect of pushing the critical stress load further into the rock mass, thus increasing safety at the rock face. To better understand the rock behaviour as a result of by pre-conditioning blasts, it is desirable to quantify the deformations of the rock face. Digital photogrammetry provides an ideally suited method of monitoring these deformations, as the necessary equipment is portable and easy to use underground, where the conditions are extreme with temperatures approaching 40°C and humidity levels close to 100%. Digital photogrammetric techniques are also highly accurate, and can be used to detect relatively small three-dimensional movements. The determination of the three-dimensional (XYZ) co-ordinates of the rock face, represented by densely spaced individual points, by means of digital photogrammetric techniques, is reported in this thesis. The novel measurement system developed comprises the following components: * establishment of a stable reference co-ordinate system; * image acquisition; * camera calibration and exterior orientation calculation; * feature extraction; * multi-image matching and space intersection; and * surface modelling. The details of the techniques developed and implemented in order to generate the necessary object space co-ordinates are discussed. Sub-millimetre accuracy point determination, as required for deformation analysis was achieved and a sample of the underground test result data is presented. The final analysis of the underground test data made it apparent that digital photogrammetry is highly suitable for the determination of digital terrain models of the rock surfaces, for subsequent deformation analysis. The relative speed of the process and the convenient size of the equipment makes the technology especially suitable to the demanding underground mining environment. The difficulties, which were experienced as a result of the highly restrictive environment, were overcome through careful planning and pre-analysis. It can thus be concluded that this approach is not only feasible, but it meets the stringent demands of the underground mining industry, as is confirmed by the high accuracy of the final surface point co-ordinates achieved. In addition to being implemented in the underground mining industry, the measurement system developed was used for the mapping of several other textured surfaces. In particular it was used in mapping the 3.6 million-year-old hominid trackway located at Laetoli (Tanzania), the imprints of cheetah and rhinoceros for the purposes of conservation, and for the archaeological documentation of a shipwreck found off the Cape coast (South Africa). All of these applications are discussed and the results achieved presented.

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Hull, Simon Antony. "Digital photogrammetry for visualisation in architecture and archaeology." Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/4987.

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Bibliography: leaves 117-125.
The task of recording our physical heritage is of significant importance: our past cannot be divorced from the present and it plays an integral part in the shaping of our future. This applies not only to structures that are hundreds of years old, but relatively more recent architectural structures also require adequate documentation if they are to be preserved for future generations. In recording such structures, the traditional 2D methods are proving inadequate. It will be beneficial to conservationists, archaeologists, researchers, historians and students alike if accurate and extensive digital 3D models of archaeological structures can be generated. This thesis investigates a method of creating such models, using digital photogrammetry. Three different types of model were generated: 1. the simple CAD (Computer Aided Design) model; 2. an amalgamation of 3D line drawings; and 3. an accurate surface model of the building using DSMs (Digital Surface Models) and orthophotos.

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Korpela, Ilkka. "Individual tree measurements by means of digital aerial photogrammetry." Helsinki : Finnish Forest Research Institute, Finnish Society of Forest Science, 2004. http://catalog.hathitrust.org/api/volumes/oclc/55872310.html.

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Walstra, Jan. "Historical aerial photographs and digital photogrammetry for landslide assessment." Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/2501.

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This study demonstrates the value of historical aerial photographs as a source for monitoring long-term landslide evolution, which can be unlocked by using appropriate photogrammetric methods. The understanding of landslide mechanisms requires extensive data records; a literature review identified quantitative data on surface movements as a key element for their analysis. It is generally acknowledged that, owing to the flexibility and high degree of automation of modern digital photogrammetric techniques, it is possible to derive detailed quantitative data from aerial photographs. In spite of the relative ease of such techniques, there is only scarce research available on data quality that can be achieved using commonly available material, hence the motivation of this study. In two landslide case-studies (the Mam Tor and East Pentwyn landslides) the different types of products were explored, that can be derived from historical aerial photographs. These products comprised geomorphological maps, automatically derived elevation models (DEMs) and displacement vectors. They proved to be useful and sufficiently accurate for monitoring landslide evolution. Comparison with independent survey data showed good consistency, hence validating the techniques used. A wide range of imagery was used in terms of quality, media and format. Analysis of the combined datasets resulted in improvements to the stochastic model and establishment of a relationship between image ground resolution and data accuracy. Undetected systematic effects provided a limiting constraint to the accuracy of the derived data, but the datasets proved insufficient to quantify each factor individually. An important advancement in digital photogrammetry is image matching, which allows automation of various stages of the working chain. However, it appeared that the radiometric quality of historical images may not always assure good results, both for extracting DEMs and vectors using automatic methods. It can be concluded that the photographic archive can provide invaluable data for landslide studies, when modern photogrammetric techniques are being used. As ever, independent and appropriate checks should always be included in any photogrammetric design.

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Pope, A. J. "Recent change of Svalbard glaciers quantified using digital photogrammetry." Thesis, Swansea University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638550.

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Understanding the response of glaciers to climate change is critical if estimates of future sea level rise are to be better constrained. A significant portion of recent sea level rise is thought to be from small glaciers, unfortunately these are scattered around the world making their contribution extremely difficult to quantify. Contributions tend to be reported for regions or groupings of glaciers and one of the regions with the largest potential contribution is the Arctic. This region has been identified as being extremely sensitive to climate fluctuations and is expected to be one of the first regions to respond to future climate change. The aim of this research is to quantify the surface change two key glaciers on Svalbard, one of the largest groupings, of glaciers in the Arctic. Surface change will be quantified through the use of Digital Elevation Models (DEMs) derived from aerial images. The quality of the derived surface is dependent on the quality of the ground data used to generate and validate the model. For this reason, extensive field work was conducted to install a network of accurate GPS points around the study glaciers. A Failure Warning Model (FWM) method is used to assess the reliability of the DEMs and the technique is developed through the implementation of a Multiple input Failure Warning Model (MiFWM) method that is more robust. This thesis shows that both study glaciers have experienced significant change during the study period. The calculated rates of change were comparable both to other ground based estimates and other photogrammetric estimates. In addition, the results do not contradict the suggestion that ground based monitoring methods consistently underestimate glaciers contribution to sea level.

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Van, der Vlugt Graeme. "Algorithms and design aspects of an automated vision based 3-D surface measurement system." Doctoral thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/15943.

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Bibliography: pages 122-132.
This thesis reports on the investigation, development and implementation of digital/photogrammetric algorithms into a compatible system for measuring surfaces. Each of the important stages of such a measurement are dealt with in the text. Specifically, these include camera calibration, free network adjustment, location and centering of circular targets, orientation determination, the matching and measuring process and handling of results. The chosen algorithms (existing, modified and/or developed in this work) were all incorporated/designed to form an efficient and usable surface measurement system. Of particular importance was the investigation of determining conjugate (matching) surface points in the multiple images. In this respect a novel multi-image correlation search procedure was designed, implemented and tested. This algorithm provides high accuracy matching methods with suitably close provisional matching positions. A series of tests was carried out to study the performance of the algorithm and the results are presented in this work. Most notable was the method's high reliability when using more than two images, even in image areas with highly repetitive patterns. Multi-image correlation is considerably more robust than "traditional" stereo-correlation procedures. Other system tests performed included: tests on the stability of projected light from two off-the shelf projection devices; a test on the effect of PLL synchronisation of the camera-framegrabber combination of the images; tests on the accuracy performance of different centering techniques and surface measurements themselves. It was found that the off-the-shelf slide projector tested did not provide a stable projection, however an overhead projector which was warmed up for over an hour provided a suitably stable projection. The PLL synchronisation of the camera-framegrabber system produced a noticeable line-jitter (between sequential images) reaching over 0.1 pixels in the most badly affected lines. In a simulated test with artificial targets, template matching obtained the most accurate centre coordinates, however the much faster weighted centre of gravity with grey value as weight technique also provides highly accurate results. These two centering techniques agreed to 1/100th of a pixel when centering with real targets. The much faster centroiding technique is thus highly recommended for any application which requires high processing speeds (such as with on-line systems). Surface measurement precisions of 5/100th mm in the plane of the surface and 15/100th mm in depth were achieved in the measurements of the test objects. These objects all had similar dimensions with a diagonal of about 250mm in length. These accuracies could be substantially improved with higher resolution cameras and more images. Together, the algorithms presented in this work formed a surface measurement software program. The success of many of these algorithms, such as the target location method, and the semi-automatic point identification and exterior orientation determination procedure, could not be gauged with results as such, but by their successful incorporation into the system as properly functioning units.

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Davey, Justin John. "Object reconstruction using close-range all-round digital photogrammetry for applications in industry." Master's thesis, University of Cape Town, 1999. http://hdl.handle.net/11427/17544.

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Bibliography: p. 66-68.
Photogrammetry has many inherent advantages in engineering and industrial applications, which include the ability to obtain accurate, non-contact measurements from data rapidly acquired with the object in situ. Along with these advantages, digital photogrammetry offers the potential for the automation or semi-automation of many of the conventional photogrammetric procedures, leading to real-time or near real-time measurement capabilities. However, all-round surface measurement of an object usually benefits less from the above advantages of photogrammetry. To obtain the necessary imagery from all sides of the measurement object, real-time processing is nearly impossible, and it becomes difficult to avoid moving the object, thus precluding in situ measurement. However, all-round digital photogrammetry and, in particular, the procedure presented here, still offer advantages over other methods of full surface measurement, including rapid, non-contact data acquisition along with the ability to store and reprocess data at a later date. Conventional or topographic photogrammetry is well-established as a tool for mapping simple terrain surfaces and for acquiring accurate 3-D point data. The complexities of all-round photogrammetry make many of the standard photogrammetric methods all but redundant. The work presented in this thesis was aimed at the development of a reliable method of obtaining complete surface data of an object with non-topographic, all-round, close-range digital photogrammetry. A method was developed to improve the integrity of the data, and possibilities for the presentation and visualisation of the data were explored. The potential for automation was considered important, as was the need to keep the overall time required to a minimum. A measurement system was developed to take as input an object, and produce as output an accurate, representative point cloud, allowing for the reconstruction of the surface. This system included the following procedures: ■ a novel technique of achieving high-accuracy system pre-calibration using a cubic control frame and fixed camera stations, ■ separate image capture for the control frame and the object, ■ surface sub-division and all-round step-wise image matching to produce a comprehensive 3-D data set, ■ point cloud refinement, and ■ surface reconstruction by separate surface generation. The development and reliability of these new approaches is discussed and investigated; and the results of various test procedures are presented. The technique of system pre-calibration involved the use of a mechanical device - a rotary table - to impart precisely repeatable rotations to the control frame and, separately, the object. The actual repeatability precision was tested and excellent results achieved, with standard deviations for the resected camera station coordinates of between 0.05 and 0.5 mm. In a detailed test case, actual rotations differed from the desired rotations by an average of 0.7" with a standard deviation of less than 2'. The image matching for the test case, from a set of forty-eight images, achieved a satisfactory final accuracy, comparable to that achieved in other similar work. The meaningful reconstruction of surfaces presented problems, although an acceptable rendering was achieved, and a thorough survey of current commercially available software failed to produce a package capable of all-round modelling from random 3-D data. The final analysis of the results indicated that digital photogrammetry, and this method in particular, are highly suited to accurate all-round surface measurement. The potential for automation - and, therefore, for near real-time results - of the method in the stages of image acquisition and processing, calibration, image matching and data visualisation is great. The method thus lends itself to industrial applications. However, the need for a robust and rapid method of surface reconstruction needs to be fulfilled.

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Calitz, Michaelangelo Franco. "Image understanding and feature extraction for applications in industry and mapping." Doctoral thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/15942.

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Bibliography: p. 212-220.
The aim of digital photogrammetry is the automated extraction and classification of the three dimensional information of a scene from a number of images. Existing photogrammetric systems are semi-automatic requiring manual editing and control, and have very limited domains of application so that image understanding capabilities are left to the user. Among the most important steps in a fully integrated system are the extraction of features suitable for matching, the establishment of the correspondence between matching points and object classification. The following study attempts to explore the applicability of pattern recognition concepts in conjunction with existing area-based methods, feature-based techniques and other approaches used in computer vision in order to increase the level of automation and as a general alternative and addition to existing methods. As an illustration of the pattern recognition approach examples of industrial applications are given. The underlying method is then extended to the identification of objects in aerial images of urban scenes and to the location of targets in close-range photogrammetric applications. Various moment-based techniques are considered as pattern classifiers including geometric invariant moments, Legendre moments, Zernike moments and pseudo-Zernike moments. Two-dimensional Fourier transforms are also considered as pattern classifiers. The suitability of these techniques is assessed. These are then applied as object locators and as feature extractors or interest operators. Additionally the use of fractal dimension to segment natural scenes for regional classification in order to limit the search space for particular objects is considered. The pattern recognition techniques require considerable preprocessing of images. The various image processing techniques required are explained where needed. Extracted feature points are matched using relaxation based techniques in conjunction with area-based methods to 'obtain subpixel accuracy. A subpixel pattern recognition based method is also proposed and an investigation into improved area-based subpixel matching methods is undertaken. An algorithm for determining relative orientation parameters incorporating the epipolar line constraint is investigated and compared with a standard relative orientation algorithm. In conclusion a basic system that can be automated based on some novel techniques in conjunction with existing methods is described and implemented in a mapping application. This system could be largely automated with suitably powerful computers.

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Dingle, Malcolm Robert. "Determining the parameters of cylinders using digital photogrammetry for application to pipe measurement in industrial plants." Doctoral thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/17545.

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Bibliography: p.187-193.
The maintenance and expansion of piping systems of petro-chemical plants is a complex and costly process. These costs can be reduced by knowledge of the as-built dimensions and layout of the piping system. As-built Computer Aided Design (CAD) models of such piping systems, specifically the use of Plant Design System (PDS) software packages, allow for more efficient planning than paper plans. Conventional surveying and analogue photogrammetry have been methods that have traditionally been used to capture the necessary CAD information. More recently, the Department of Geomatics at the University of Cape Town has produced software which replicates the analogue photogrammetric approach using digital images (Cammidge, 1996). The objective of this thesis is to develop a pipe measurement technique which can supplement those currently being used and overcome some of their shortcomings. A further objective is to present an overview of the pipe measurement techniques, photogrammetric principles, image processing techniques and programming considerations which would be required to develop a robust, fully functional, pipe measurement software package integrated with a PDS. The author hopes that this thesis will form the foundation for the development of such a software package for local and possibly international industry. A digital photogrammetric technique related to line photogrammetry is developed. This technique makes use of lines in an image which represent the silhouette edges of the cylinder. The use of photogrammetry based on lines avoids some of the shortcomings of conventional point-based photogrammetry. It is not necessary to identify conjugate points in images, nor is it even necessary for overlapping images of the cylinder to be captured. Furthermore, this thesis reports on a number of tests designed to gauge the developed techniques' accuracy and suitability for use in pipe metrology in an industrial plant. The techniques were found to be capable of achieving results which deviated by, on average, 2-3mm in object position and 0.1° in direction from the likely true values of the cylinder axis. The radius could be determined to better than 1 mm. The techniques developed here proved to be suitably accurate for the purpose of determining the parameters of pipes in industrial plants. However, certain factors may reduce the accuracy and these are also discussed. This thesis concludes that a novel digital photogrammetric technique for measuring pipes in an industrial plant was successfully developed. Recommendations are made as to how the technique might be improved to allow sub-millimetre accuracies to be obtained. Finally, a recommendation is made that the information contained within the thesis be used as the basis for designing a digital photogrammetric measurement module to be linked to a PDS.

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Ching, Siu-tong, and 程肇堂. "Digital photogrammetry as a means of data capture for GIS." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30110129.

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Lee, Dong-Cheon. "An adaptive texture segmentation approach for applications in digital photogrammetry /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487948440824379.

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Bachmann, Marc. "Beitrag zur Verbesserung der Genauigkeitskenngrössen von Grossmanipulatoren im Mehrmedieneinsatz mit Hilfe der digitalen Photogrammetrie." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960902856.

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Eberhardt, Joerg. "Digital image based surface modelling." Thesis, Coventry University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245098.

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Muratoglu, Bukay. "Monitoring Bulbulderesi And Bakacak Landslides With Photogrammetric Techniques." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610586/index.pdf.

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Every year, thousands of people all over the world are loosing their lives in natural disasters. As a second most widespread hazard, landslides are still a disaster problem for Turkey. The long-term monitoring studies of instability phenomena have a paramount importance for Turkey to reduce its both direct and indirect effects. The objective of this thesis is to monitor the activity of the Bü
lbü
lderesi and Bakacak landslides in Asarsuyu Catchment for 42 years period by the digital aerial photogrammetric techniques while evaluating the possible use of archive aerial photography in such analysis. To achieve the purpose of the study an orthophoto map was generated by aerial photographs belonging to 1994 year. The orthophoto map was utilized as a base map for aerial photo interpretation of different sets of aerial photographs corresponding to 1952, 1972, 1984 and 1994 years. As a result of this, 4 landslide activity maps are obtained. In addition, the characteristics of these landslides are analyzed by utilizing digital elevation model (DEM) created from stereo photographs of 1994. As a result of the study, no considerable variation is detected in the position of main boundaries of Bü
lbü
lderesi and Bakacak landslides except some minor differences. However, within the landslides many topographical changes were observed between 1952 and 1994 period. Based on the profiles from toe to crest of the Bü
lbü
lderesi landslide, the approximate length was measured as 4773m whereas the approximate width was about 2614m. The areal extent was calculated as ~12km2 having an approximate slope gradient ranging between 10-15°
with local variations. On the other hand, the approximate length of Bakacak landslide was 4420m and the approximate width was 832m from toe to crest with an area of ~4km2 and with an approximate slope angle 9-14°
.

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Macay, Moreira José Miguel. "Using photogrammetric Digital Surface Model in LiDAR software for creating Three Dimensional Buildings." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14724.

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The way of representing Earth has changed; two dimensional (2D) maps have turned into three Dimensional (3D) representations. There are many studies in order to create 3D city maps as well as areas where these are applied such as 3D cadastral, 3D visualization and flood simulation, etc. These can be created with the aid of different data sources using photogrammetric Digital Surface Model (DSM) derived from image matching and from Light Detection and Ranging (LiDAR) point clouds or both of them combining orthophotos and building footprints. Several software has been developed to ease and speed up this process. In this study, a current state-of-the art in the 3D city modeling with particular interest to commercial software was analyzed. DSMs from image matching (Satellite and Airborne) were used in order to create a 3D city model of Trento, Italy. The objectivewas to examine the degree of automation and the computation time of two available software: Feature Manipulation Engine (FME) and Building Reconstruction (BREC). Other problem such as the quality of the DSM needed would be discussed for each software and the results would be compared to those achieved using LiDAR data. Recommendations and possible problems would also be addressed. In order to create a 3D city model, the ALDPAT software (Airborne LiDAR Data Processing and Analysis Tool) has been used to separate the ground regions (Digital Terrain Model, DTM) from the man-made objects and trees (Normal Digital Surface Model, nDSM). FME and BREC software have been used to reconstruct the 3D city model. The output results from FME and BREC have been analyzed qualitatively and quantitatively. The comparison between the models generated from photogrammetric and LiDAR DSMs have been performed. The results show that buildings generated by satellite images have poorest quality compared with buildings from LiDAR and airborne data. In particular, the performed tests will be shown that among the Level of Details (LoD), a LoD1 and LoD2 3D city models can be generated using a DSM by image matching. A deeper study should be done in order to analyze the level of detail qualitatively.

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Mills, Jonathan Philip. "The implementation of a digital photogrammetric system and its application in civil engineering." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481736.

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Davis, Dexter Justin Ainsley. "The development of a digital photogrammetric map revision system for use in developing countries." Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387477.

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Hochstöger, Franz. "Ein Beitrag zur Anwendung und Visualisierung digitaler Geländemodelle : Veröffentlichung des Institutes für Photogrammetrie u. Fernerkundung /." Wien : Inst. für Photogrammetrie u. Fernerkundung, 1989. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=001770679&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Morgado, Ana M. de O. "Automated procedures for orientation of digital images." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339803.

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Meneguette, Arlete Aparecida Correia. "Cartographic accuracy and information content of space imagery for digital map compilation and map revision." Thesis, University College London (University of London), 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295491.

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Gyftakis, Sotirios. "Image-based Change Detection of Geospatial Objects Using Positional Uncertainty." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/GyftakisS2005.pdf.

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Fey, Matthew F. "Digital outcrop mapping of a reservoir-scale incised valley fill, Sego Sandstone, Book Cliffs, Utah." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1794.

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Arslaner, Ege Candeniz. "Integration of 3D data from the ancient city of Karkemish by Digital Photogrammetry." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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The thesis addresses the topic of rigorous reconstruction of an archaeological context, no longer existing, by using 3D models generated by a modern photogrammetric approach. The case of study is the ancient city of Karkemish, in Turkey. This beautiful city was forgotten for more than a thousand years. Then it was finally rediscovered more than a hundred years ago; unfortunately, many beautiful historical artifacts of the city scattered to London, Paris, Ankara, and many other places in the world. In order to demonstrate original appearance of the Long Wall of the Sculpture, digital photogrammetry method is applied, with a Structure from Motion Multi-View approach derived from Computer Vision. Thank to these recent methodologies, digital photogrammetry is more and more a universal technique for 3D model generation, applied in a wide range of interdisciplinary fields and very useful in surveying archaeological sites. During the thesis work, the 3D model of the Karkemish site was generated by ContextCapture software; the 3D model of the orthostats of the Long Wall of the Sculpture was instead created by PhotoScan software. After generation process, the models of the orthostats were modified by Blender software in order to create a realistic appearance. A similar process was applied for the 3D model of the city. Georeferencing was performed thanks to topographical surveys carried out on the site and the Digital Elevation Model. As the last step, all the orthostats have been imported one by one into their original positions, recreating the situation before their transfer in the Anatolian Civilizations Museum in Ankara.

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Lakshmi, Sia S. "Improved material characterisation of anisotropic automotive aluminium alloys using digital close range photogrammetry." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490098.

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It is necessary to select appropriate constitutive material models, and evaluate required parameters for materials used in full-vehicle FE simulations. The parameters for these constitutive material models are usually evaluated by monitoring uniaxial force-extension data from small-scale parallel gauge section specimens. During the material model/parameter verification process, discrepancies between experimental and FE data have been observed. The predictive performance of material models has been held responsible for this discrepancy, however a number of other issues are known to accentuate this disagreement, and the focus of this thesis lies here.

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Telles, Sandra Stephan de Souza [UNESP]. "Um Modelo para calibração de câmaras digitais baseado em linhas retas." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/86774.

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Made available in DSpace on 2014-06-11T19:22:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2004Bitstream added on 2014-06-13T20:28:45Z : No. of bitstreams: 1 telles_sss_me_prud.pdf: 1366929 bytes, checksum: 8f13eb812304d2c1702fcb81ecb51119 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Com o aumento do uso das câmaras digitais não métricas em aplicações fotogramétricas, tem crescido a necessidade pela calibração destas câmaras e pela freqüência de realização desta. Com o objetivo de tornar mais simples a utilização e a automação desta etapa, foi desenvolvido um modelo matemático para calibração que usa feições retas, baseado no modelo dos planos equivalentes, com estimação dos parâmetros pelo método combinado. O modelo foi implementado em linguagem C++ em conjunto com o método convencional que usa as equações de colinearidade, de modo a permitir tanto a calibração com pontos quanto com retas. O método foi testado com dados simulados e dados reais e apresentou resultados satisfatórios, compatíveis com o modelo convencional. Para os experimentos com dados reais, foi ainda implementado um programa de extração de bordas com precisão subpixel.
Nowadays, digital cameras have been more and more employed in photogrammetric applications. However, the geometric of common camera is not rigid as metric cameras. Therefore, the need for camera calibration has been increasing; moreover it is important to be frequent. The use of straight lines can lead to an easy and fast camera calibration process due to the promising possibility of automation in the line extraction process. Following this thought, a mathematical model, based on the model of equivalent planes, was developed to include inner orientation parameters, using straight lines. This model was implemented using the unified method of adjustment with weight constraint to the parameters. The implemented program was tested using simulate and real data. The results have shown the developed model is comparable to the conventional one using control points. A feature extraction method aiming sub-pixel precision was implemented as well.

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Browbank, Ian. "Intraoperative registration for robotic-assisted orthopaedic surgery : a digital X-ray photogrammetry based technique." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/12934.

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Changes in orthopaedic practice have led to an increased reliance upon fluoroscopic image-guidance during fracture fixation (osteosynthesis) procedures. The resulting complexity of surgical techniques, and concerns over X-ray radiation exposure levels to orthopaedic surgeons, has prompted an investigation of robotic-assisted orthopaedic surgery, with a view to improving the precision, repeatability and radiation safety of existing fluoroscopically-guided bone drilling procedures. A prerequisite for such an application is to establish the patient's location with respect to the robotic manipulator. Owing to the inherent nature of osteosynthesis procedures, this intraoperative registration process can only be performed by quantifying the existing fluoroscopic examination process. A digital X-ray photogrammetry based registration technique, which uses a radiolucent robot-mounted X-ray calibration frame, has therefore been investigated. When this calibration frame is simultaneously imaged with the patient, discrete registration markers, corresponding to radiopaque fiducials embedded in the frame, are superimposed into the standard intraoperative X-ray images. Digitising these images, using a PC-based frame grabber card, has allowed semi-automatic image analysis routines to be implemented. Applying correction-calibration software, which provides on-line compensation for image distortion effects, then allows the imaged part of the patient's skeleton to be located, with respect to the calibration frame's coordinate system, thus establishing intraoperative registration. In vitro laboratory-based trials of this registration technique indicate that reconstruction errors are in the sub-millimetre range. As such, this new approach represents a low cost non-invasive registration option, which fully adheres to "operating room compatibility" criteria, and is applicable to a wide range of osteosynthesis procedures. Significantly, by extending the technique to include quantification of the trajectory plarming process, it has also been possible to demonstrate major improvements over existing surgical techniques.

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Gooch, Michael J. "Accuracy optimisation and error detection in automatically generated elevation models derived using digital photogrammetry." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/7347.

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Users of current Digital Photogrammetric Systems (DPS) can now rapidly generate dense Digital Elevation Models (DEMs) with a minimal amount of training. This procedure is controlled through a set of strategy parameters embedded in the software. Previous research into the effect of these parameters on the resulting DEMs produc'ed mixed results, with some researchers finding that significant changes to the DEM can be made through manipulation of the parameters whilst others suggested that they have little effect. This thesis builds upon this early work to develop two systems that provide assistance for novice users. The first technique optimises the parameters with respect to DEM accuracy and takes the form of an expert system and compares the output from the DEM with a knowledge base to prescribe an improved set of parameters. The results suggest that the system works and can produce improvements in the accuracy of a DEM. It was found that in certain circumstances, changes to the parameters can have a significant effect on the resulting DEM, but this change does not occur across the entire DEM. The second aspect of the thesis details the development of a completely new approach that automatically detects low accuracy areas of the DEM and presents this information graphically. This is an important development since, as documented in the current literature, few quality control procedures are offered to users. The user can use this information to assist in the manual checking and editing of the final DEM, thus speeding up the workflow and improving the accuracy of the output. The results of tests (using the ERDAS Imagine OrthoMAX software) on a wide variety of imagery are presented and show that the technique reliably detects areas of a DEM with high errors. More significantly, the technique has also been tested on two other DPSs (Zeiss Phodis TS and VirtuoZo) and it was found that it worked well for the Zeiss system but could not be applied to the VirtuoZo software. This demonstrates that the research is not limited to the users of one software package and is of interest to the wider photogrammetric community.

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Sieberth, Till. "Motion blur in digital images : analys, detection and correction of motion blur in photogrammetry." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/20212.

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Unmanned aerial vehicles (UAV) have become an interesting and active research topic for photogrammetry. Current research is based on images acquired by an UAV, which have a high ground resolution and good spectral and radiometrical resolution, due to the low flight altitudes combined with a high resolution camera. UAV image flights are also cost effective and have become attractive for many applications including, change detection in small scale areas. One of the main problems preventing full automation of data processing of UAV imagery is the degradation effect of blur caused by camera movement during image acquisition. This can be caused by the normal flight movement of the UAV as well as strong winds, turbulence or sudden operator inputs. This blur disturbs the visual analysis and interpretation of the data, causes errors and can degrade the accuracy in automatic photogrammetric processing algorithms. The detection and removal of these images is currently achieved manually, which is both time consuming and prone to error, particularly for large image-sets. To increase the quality of data processing an automated process is necessary, which must be both reliable and quick. This thesis proves the negative affect that blurred images have on photogrammetric processing. It shows that small amounts of blur do have serious impacts on target detection and that it slows down processing speed due to the requirement of human intervention. Larger blur can make an image completely unusable and needs to be excluded from processing. To exclude images out of large image datasets an algorithm was developed. The newly developed method makes it possible to detect blur caused by linear camera displacement. The method is based on human detection of blur. Humans detect blurred images best by comparing it to other images in order to establish whether an image is blurred or not. The developed algorithm simulates this procedure by creating an image for comparison using image processing. Creating internally a comparable image makes the method independent of additional images. However, the calculated blur value named SIEDS (saturation image edge difference standard-deviation) on its own does not provide an absolute number to judge if an image is blurred or not. To achieve a reliable judgement of image sharpness the SIEDS value has to be compared to other SIEDS values of the same dataset. This algorithm enables the exclusion of blurred images and subsequently allows photogrammetric processing without them. However, it is also possible to use deblurring techniques to restor blurred images. Deblurring of images is a widely researched topic and often based on the Wiener or Richardson-Lucy deconvolution, which require precise knowledge of both the blur path and extent. Even with knowledge about the blur kernel, the correction causes errors such as ringing, and the deblurred image appears muddy and not completely sharp. In the study reported in this paper, overlapping images are used to support the deblurring process. An algorithm based on the Fourier transformation is presented. This works well in flat areas, but the need for geometrically correct sharp images for deblurring may limit the application. Another method to enhance the image is the unsharp mask method, which improves images significantly and makes photogrammetric processing more successful. However, deblurring of images needs to focus on geometric correct deblurring to assure geometric correct measurements. Furthermore, a novel edge shifting approach was developed which aims to do geometrically correct deblurring. The idea of edge shifting appears to be promising but requires more advanced programming.

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38

Hsia, Jung-Sheng. "A new method for the automated production of digital terrain models using a combination of feature points, grid points and filling back points." Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337379.

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39

Mountrakis, Georgios. "Image-Based Change Detection Using An Integrated Spatiotemporal Gazetteer." Fogler Library, University of Maine, 2000. http://www.library.umaine.edu/theses/pdf/Mountrakis2000.pdf.

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40

Park, David W. G. "Using linear features for absolute and exterior orientation." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323256.

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41

Oliveira, Rafael Montanhini Soares de. "Extração de rodovias utilizando SNAKES /." Presidente Prudente : [s.n.], 2003. http://hdl.handle.net/11449/88544.

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Orientador: Aluir Porfírio dal Poz
Resumo: A obtenção de informações a partir da extração de feições em fotos aéreas e imagens de satélite é um dos principais objetivos da nova tecnologia de automação em Fotogrametria Digital. Este trabalho propõe a extração de rodovias, e a conexão de segmentos de rodovias extraidos por outros extratores de feições, utilizando modelos de contorno ativo ou snakes. Snakes foi introduzido há quase duas décadas e consiste em uma curva representada parametricamente e controlada por injunções fotométricas e geométricas: fotométricas, chamadas de força da imagem que atraem a curva snakes para a feição a ser extraída (rodovia); geométricas, geradas pelas forças internas que controlam a forma da curva snakes garantindo sua suavidade. Por ser um método de extração semi-automático, inicialmente o operador deve descrever a rodovia de maneira grosseira utilizando no mínimo seis pontos sementes. A partir desta posição inicial a curva snakes evolui a cada iteração fazendo com que a mesma se posicione sobre a borda da rodovia (feição a ser extraída) onde sua energia é minimizada. O método snakes foi implementado em linguagem C e testado na extração e conexão de segmentos de rodovia em imagens de alta (pixels menores 0.7m), média (pixels entre 0.7m e 2.0m) e baixa (pixels maiores 2.0m) resolução, mostrando-se bastante eficiente em todos os casos, mesmo na presença de obstáculos que perturbam o perfeito delineamento da rodovia. Através da extração de bordas de rodovia, em imagens de alta e média resolução, foi gerado um eixo interpolado e comparado com o eixo de referência utilizado para avaliação. Utilizando avaliações visuais e numéricas foi possível comprovar a boa acuracia do processo de extração e conexão de segmentos utilizando snakes.
Abstract: Obtaining information from the extraction of aspects from aerial photographs and satellite images is one of the main purposes of the new technology in Digital Photogrammetry. This study proposes extracting roads and linking the segments of the extracted roads by means of other extractors of aspects, by using models of active contour, or snakes. Snakes was introduced almost two decades ago, and it consists in a parametrically represented curve, controlled by photometric and geometric injunctions: photometric injunctions, called image power, that attract the snakes curve for the aspect to be extracted (road); geometric injunctions, generated by internal powers that control the shape of the snakes curve, thus insuring its smoothness. As it is a semi-automatic extraction process, the operator shall initially describe the road roughly, using at least six seed points. From this initial position, the snakes curve evolves at each iteration, placing itself over the road edge (aspect to be extracted), where its power is minimized. The snakes method was implemented in language C and tested in the extraction and link of road segments in images of high resolution (pixels lower than 0.7m), medium resolution (pixels between 0.7m and 2.0m) and low resolution (pixels higher than 2.0m), and it turned out to be very efficient in both cases, even in the presence of obstacles that disturb the perfect road outlining. With the extraction of road edges in high and medium resolution images, one interpolated axis was generated, and it was compared to the reference axis used in the evaluation. By using visual and numerical evaluations, it was possible to prove the accuracy provided by the process of extraction and link of segments that uses the snakes method.
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42

Naim, W. M. W. M. "An evalution of low-cost digital photogrammetry and GIS in a landfill site selection process." Thesis, University of Edinburgh, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.659855.

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This study concerns the use of particular technologies and of Geographical Information System (GIS) as tools to aid effective planning and decision making in the context of a Developing Country such as Malaysia. As in other Developing Countries, the main problems of using GIS within small organisations such as local authorities and planning authorities in Malaysia are associated with the availability of data, the availability of skilled personnel and the constraints of budgets. A low-cost digital data acquisition method that includes the use of low-cost scanners and a low-cost digital photogrammetric workstation (DPW) are proposed for generating some of the necessary data. The proposed low-cost method includes the use of low-cost A4 format desktop publishing scanners (DTP) and the Desktop Mapping System (DMS) version 3.1, which is a PC-based digital photogrammetric workstation (DPW). The ARC/INFO version 6.1 software has been employed as the data integration, data visualisation and data analysis tool. A series of tests on DTP scanners and digital photogrammetric products generated from a low-cost DPW have been carried out to confirm that these low-cost data acquisition methods are suitable for generating the required digital data accurately, quickly and without the need for highly skilled personnel. Results from accuracy assessment of DTP scanners have indicated that, while the distortion errors introduced by DTP scanner imperfection are significant, they can be minimised using proper calibration procedures. Results for accuracy assessment have further indicated that high quality DEMs and orthoimages can be produced with a low-cost DPW provided high quality aerial photo images and ground control points are available. The Petaling District in the Klang Valley Region, Malaysia has been used as the study area to demonstrate the role of digital photogrammetry, satellite remote sensing and GIS in the stage-by stage site selection process.

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43

Barrand, Nicholas Edward. "Changes in volume and extent of NW Svalbard glaciers using airborne lidar and digital photogrammetry." Thesis, Swansea University, 2007. https://cronfa.swan.ac.uk/Record/cronfa43028.

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Monitoring fluctuations in the mass of the Earth's ice-sheets, ice-caps and glaciers is of fundamental societal importance due to their direct and measurable effects on global sea-levels. Uncertainty in the sea-level rise contribution from small glaciers and ice-sheets exists in part due to problems of sample size, distribution and scaling of long-term mass balance measurements. Photogrammetric processing of aerial photography archives offers the opportunity to reconstruct historical mass changes for regions where no such data are available. The ability to derive DEM measurements of glacier volume from photogrammetry is dependent on image texture for surface-matching and good quality, well-distributed ground reference data, which are often difficult to acquire. The aim of this research was to examine the quality (vertical elevation accuracy) of airborne laser scanning (lidar) data in order to utilise raw point data as ground control in historical photogrammetric models. This technique was then used to measure volume changes at NW Svalbard glaciers, thus circumventing the need to measure control in the field. Precision and accuracy of lidar data were found to vary both within and between the lidar swaths, and large numbers of raw lidar points were successfully used to control photogrammetric models. DEMs produced using lidar-derived points were optimised to produce volume change measurements comparable to those from lidar-lidar model differencing. Poorly controlled photogrammetry was shown to overestimate changes in glacier volume by as much as 50%. Two glaciers in NW Svalbard were shown to be losing mass at an accelerating rate, since 1966 and 1990 respectively, in response in increases in average summer air temperatures. Average present-day mass loss was greater than previously estimated, suggesting an increased contribution to sea-level rise from Svalbard glaciers. This method provides a powerful tool for exploiting image archives and may be used in the future to generate high-quality measurements of glacier mass balance.

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44

Wan, Mohd Wan Mohd Naim. "An evaluation of low-cost digital photogrammetry and GIS in a landfill site selection process." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/22720.

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45

Jaafar, Jasmee. "An evaluation of the generation and potential applications of digital surface models." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326567.

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46

Oliveira, Rafael Montanhini Soares de [UNESP]. "Extração de rodovias utilizando SNAKES." Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/88544.

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Made available in DSpace on 2014-06-11T19:23:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T19:09:22Z : No. of bitstreams: 1 oliveira_rms_me_prud.pdf: 2936252 bytes, checksum: 250c550ac7923d26a59bbd1cb2bb5287 (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A obtenção de informações a partir da extração de feições em fotos aéreas e imagens de satélite é um dos principais objetivos da nova tecnologia de automação em Fotogrametria Digital. Este trabalho propõe a extração de rodovias, e a conexão de segmentos de rodovias extraidos por outros extratores de feições, utilizando modelos de contorno ativo ou snakes. Snakes foi introduzido há quase duas décadas e consiste em uma curva representada parametricamente e controlada por injunções fotométricas e geométricas: fotométricas, chamadas de força da imagem que atraem a curva snakes para a feição a ser extraída (rodovia); geométricas, geradas pelas forças internas que controlam a forma da curva snakes garantindo sua suavidade. Por ser um método de extração semi-automático, inicialmente o operador deve descrever a rodovia de maneira grosseira utilizando no mínimo seis pontos sementes. A partir desta posição inicial a curva snakes evolui a cada iteração fazendo com que a mesma se posicione sobre a borda da rodovia (feição a ser extraída) onde sua energia é minimizada. O método snakes foi implementado em linguagem C e testado na extração e conexão de segmentos de rodovia em imagens de alta (pixels menores 0.7m), média (pixels entre 0.7m e 2.0m) e baixa (pixels maiores 2.0m) resolução, mostrando-se bastante eficiente em todos os casos, mesmo na presença de obstáculos que perturbam o perfeito delineamento da rodovia. Através da extração de bordas de rodovia, em imagens de alta e média resolução, foi gerado um eixo interpolado e comparado com o eixo de referência utilizado para avaliação. Utilizando avaliações visuais e numéricas foi possível comprovar a boa acuracia do processo de extração e conexão de segmentos utilizando snakes.
Obtaining information from the extraction of aspects from aerial photographs and satellite images is one of the main purposes of the new technology in Digital Photogrammetry. This study proposes extracting roads and linking the segments of the extracted roads by means of other extractors of aspects, by using models of active contour, or snakes. Snakes was introduced almost two decades ago, and it consists in a parametrically represented curve, controlled by photometric and geometric injunctions: photometric injunctions, called image power, that attract the snakes curve for the aspect to be extracted (road); geometric injunctions, generated by internal powers that control the shape of the snakes curve, thus insuring its smoothness. As it is a semi-automatic extraction process, the operator shall initially describe the road roughly, using at least six seed points. From this initial position, the snakes curve evolves at each iteration, placing itself over the road edge (aspect to be extracted), where its power is minimized. The snakes method was implemented in language C and tested in the extraction and link of road segments in images of high resolution (pixels lower than 0.7m), medium resolution (pixels between 0.7m and 2.0m) and low resolution (pixels higher than 2.0m), and it turned out to be very efficient in both cases, even in the presence of obstacles that disturb the perfect road outlining. With the extraction of road edges in high and medium resolution images, one interpolated axis was generated, and it was compared to the reference axis used in the evaluation. By using visual and numerical evaluations, it was possible to prove the accuracy provided by the process of extraction and link of segments that uses the snakes method.

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47

Klingmann, Scot. "The application of a digital photogrammetry system to structural mapping at a large open pit mine." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37959.pdf.

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48

Wilson, Stuart B. "Morphological analysis and mapping of Loch Lomond Stadial moraines using digital photogrammetry and geographical information systems." Thesis, University of Glasgow, 2005. http://theses.gla.ac.uk/4403/.

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Morphological analysis and mapping of Loch Lomond Stadial moraines at five key sites, Torridon, Rannoch Moor, Tyndrum and Strath Fillan, the upper Forth Valley and the east Loch Lomond basin has allowed the genetic interpretation and inferences of climatic significance to made. Hummocky moraine is found at three of these sties, Torridon, Rannoch Moor and Tyndrum, where they are interpreted as polygenetic in origin. The spatial organisation and morphology of hummocky features investigated in Torridon allows the differentiation of cross-valley orientated marginal moraines and the more numerous streamlined features with a down-valley orientation interpreted as flutings. As the flutings are superimposed on the cross-valley moraines they are thought to post-date moraine formation. The spatial organisation of glacial landforms in Torridon therefore represents a palimpsest landscape. Mapping of moraines in the Rannoch Moor basin suggests that this was a major centre of ice convergence rather than accumulation during the Loch Lomond Stadial. Ice mainly accumulated in the corries in the mountains to the west of moor from where it flowed to coalesce as an upland icefield. Ice is thought to have reached a sufficient volume in the Rannoch Moor basin to flow down valleys as outlet glaciers. Hummocky features found at Tyndrum and Strath Fillan have a polygenetic origin and include the remnants of eskers, hummocks produced by local ice stagnation, marginal moraines, and lateral moraines which have been modified by paraglacial debris flow. Large terraces at this sites are interpreted as kame terraces with pitted and channelled surfaces. Local ice stagnation is thought to have occurred during a regional pattern of active deglaciation.

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Telles, Sandra Stephan de Souza. "Um Modelo para calibração de câmaras digitais baseado em linhas retas /." Presidente Prudente : [s.n.], 2004. http://hdl.handle.net/11449/86774.

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Orientador: Antonio Maria Tommaselli
Resumo: Com o aumento do uso das câmaras digitais não métricas em aplicações fotogramétricas, tem crescido a necessidade pela calibração destas câmaras e pela freqüência de realização desta. Com o objetivo de tornar mais simples a utilização e a automação desta etapa, foi desenvolvido um modelo matemático para calibração que usa feições retas, baseado no modelo dos planos equivalentes, com estimação dos parâmetros pelo método combinado. O modelo foi implementado em linguagem C++ em conjunto com o método convencional que usa as equações de colinearidade, de modo a permitir tanto a calibração com pontos quanto com retas. O método foi testado com dados simulados e dados reais e apresentou resultados satisfatórios, compatíveis com o modelo convencional. Para os experimentos com dados reais, foi ainda implementado um programa de extração de bordas com precisão subpixel.
Abstract: Nowadays, digital cameras have been more and more employed in photogrammetric applications. However, the geometric of common camera is not rigid as metric cameras. Therefore, the need for camera calibration has been increasing; moreover it is important to be frequent. The use of straight lines can lead to an easy and fast camera calibration process due to the promising possibility of automation in the line extraction process. Following this thought, a mathematical model, based on the model of equivalent planes, was developed to include inner orientation parameters, using straight lines. This model was implemented using the unified method of adjustment with weight constraint to the parameters. The implemented program was tested using simulate and real data. The results have shown the developed model is comparable to the conventional one using control points. A feature extraction method aiming sub-pixel precision was implemented as well.
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50

Azizi, Ali. "The design and implementation of a purely digital stereo-photogrammetric system on the IBM 3090 multi-user mainframe computer." Thesis, University of Glasgow, 1990. http://theses.gla.ac.uk/3727/.

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This thesis is concerned with an investigation into the possibilities of implementing various aspects of a purely digital stereo-photogrammetric (DSP) system on the IBM 3090 150E mainframe multi-user computer. The main aspects discussed within the context of this thesis are:-i) Mathematical modelling of the process of formation of digital images in the space and frequency domains.ii) Experiments on improving the pictorial quality of digital aerial photos using Inverse and Wiener filters.iii) Devising and implementing an approach for the automatic sub-pixel measurement of cross-type fiducial marks for the inner orientation, using the Gradient operator and image modelling least squares (IML) approach.iv) Devising and implementing a method for the digital rectification of overlapping aerial photos and the formation of the stereo-model.v) Design and implementation of a digital stereo-photogrammetric system (DSP) and the generation of a DTM using visual measurement.vi) Investigating the feasibility of stereo-viewing of binary images and the possibility of performing measurements on such images.vii) Implementing a method for the automatic generation of a DTM using a one-dimensional image correlation along epipolar lines and experimentally optimizing the size of the correlation window.viii) Assessment of the accuracy of the DTM data generated both by the DSP and the automatic correlation method.ix) Vectorization of the rectification and correlation programs to achieve higher speed-up factors in the computational process.

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Dissertations / Theses on the topic 'Digitale Photogrammetrie'

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