This position paper highlights current problems linked to the aspects of the multi-agency collaboration during disaster response. The coordination and cooperation depend on the information sharing and use which must face up to interoperability, access rights, and quality problems. The research project aims at providing an assessment of information impact on the disaster response in order to support the decisionmaking about what information shared or what quality of data used to improve the response efficiency. Our research approach propose to combine an information system able to integrate heterogeneous data and a simulation system to assess different strategies of information sharing, dissemination and use. A knowledge base is used as a bridge between information system and simulation system. This knowledge base allows for designing dynamically a simulation according to open data and for managing the own knowledge and information known by each agent.

Experts’ knowledge about optical technologies for spatial and spectral recording is logically structured and stored in an ontology-based knowledge representation with the aim to provide objective recommendations for recording strategies. Besides operational functionalities and technical parameters such as measurement principles, instruments, and setups further factors such as the targeted application, data, physical characteristics of the object, and external influences are considered creating a holistic view on spectral and spatial recording strategies. Through this approach impacting factors on the technologies and generated data are identified. Semantic technologies allow to flexibly store this knowledge in a hierarchical class structure with dependencies, interrelations and description logic statements. Through an inference system the knowledge can be retrieved adapted to individual needs.

Im Jahresbericht werden die Aktivitäten des i3mainz in komprimierter Form vorgestellt.

Ontologies have traditionally been used to represent knowledge of a specific domain. They are also used to provide a base to infer the knowledge present inside them. However, the applications of ontologies within the Cultural Heritage (CH) community have been restricted to providing standard documentation for significant heritage objects. E.g., widely used ontology within CH disciplines, International Committee for Documentation Conceptual Reference Model (CIDOC CRM) is designed to provide standards in documenting archival information of physical CH object. There has been hardly any work relating the objects to their documentation purposes. In this paper, we present the Colour and Space in Cultural Heritage Knowledge Representation (= COSCHKR) ontology – a multi-faceted ontology. With COSCHKR, we present a system that infers inter-woven descriptive semantics of different involved CH disciplines in recording CH objects to recommend optimal spatial and spectral technical solutions to humanities experts and guide through the underlying complexities while recording their objects. It takes numbers of facts into consideration including physical characteristics of the CH objects, the characteristics of their surroundings and even other relevant facts such as budget or staff competence to infer against the characteristics of the technologies for a proper recommendation. In contrast to a typical Recommender System, which does the same for web-based content through stochastic methods, we use descriptive semantics at the concept level.

The paper presents work on implementation of semantic technologies within a geospatial environment to provide a common base for further semantic interpretation. The work adds on the current works in similar areas where priorities are more on spatial data integration. We assert that having a common unified semantic view on heterogeneous datasets provides a dimension that allows us to extend beyond conventional concepts of searchability, reusability, composability and interoperability of digital geospatial data. It provides contextual understanding on geodata that will enhance effective interpretations through possible reasoning capabilities.  We highlight this through use cases in disaster management and planned land use that are significantly different. This paper illustrates the work that firstly follows existing Semantic Web standards when dealing with vector geodata and secondly extends current standards when dealing with raster geodata and more advanced geospatial operations.

Traditionally stone inscriptions or drawings are documented through pictures or rubbings. The latter ones represent an analogue copy of the stone’s surface and its features which are reproduced on paper. The disadvantage of this technique is the physical impact to the stone and the contained elements. Images reproduce the surface without contact. However, they might be affected by geometrical distortions and need appropriate lighting conditions to show the signs properly.

These problems will be avoided by means of non-contact 3D measuring techniques, like fringe projection. Such high resolution 3D techniques provide an exact geometrical copy of the original petroglyph, offering better results in legibility compared to traditional techniques. Moreover, it gives a more objective base for analysis and has less impact on the sometimes sensitive and eroded surfaces. Furthermore 3D data allows more extensive and further possibilities in processing and gives better preconditions for the interpretation.

However, depending on factors like resolution, scanned surface and degree of overlap between individual scans original 3D datasets may represent large up to really massive volumes of data. An effective use of such datasets can only be realised if they are condensed and prepared in a suitable way. This means reduction of the data volume, minimising any disturbing influence emerging from the spatial shape of the surface and emphasizing relevant information. The corresponding preparation of the data will then be a good base for a interpretation performed by the human science specialist through an adapted visualization. In addition the data should be prepared for high performance presentation to a wider community via the internet.

Processed digital copies of the Petroglyphs are visualised in order to enable the user to inspect the processed scans of the objects. By inspecting the scans the application provides a mass of functionality for achieving different views into the Petroglyphs and their appearance. This comprises on the one hand a simple 2D viewer for the processed data, and on the other hand a 3D viewer with interactive changeable light positions and water levels as well as a viewer for applying various lookup tables (colour), predefined image filters (convolution) and template matching (matching) regarding individual characters.

Provided functionality of the 3D viewer is based on features of 3D computer graphics. Surface normal vectors from the grey values of the processed scans and a light direction vector from an interactively changeable light source are computed. In addition shading is complemented by water filling, whereby the gray values are limited by the water level selected. Individual modifications are possible to improve the subjective impression by the user, trying to support him in his process of interpretation. Interactive changes of the light source directly affect the shading of the surface and provide a better idea of the 3D surface of the inscription board. Dynamic virtual water filling enables the user to obtain an even better impression of the depth of the individual characters and emphasise weathered characters.

The paper will explain the developed techniques and document its potential at selected data sets.

Modern instruments like laser scanner and 3D cameras or image based techniques like structure from motion produce huge point clouds as base for further object analysis. This has considerably changed the way of data compilation away from selective manually guided processes towards automatic and computer supported strategies. However it’s still a long way to achieve the quality and robustness of manual processes as data sets are mostly very complex. Looking at existing strategies 3D data processing for object detections and reconstruction rely heavily on either data driven or model driven approaches. These approaches come with their limitation on depending highly on the nature of data and inability to handle any deviation. Furthermore, the lack of capabilities to integrate other data or information in between the processing steps further exposes their limitations. This restricts the approaches to be executed with strict predefined strategy and does not allow deviations when and if new unexpected situations arise. We propose a solution that induces intelligence in the processing activities through the usage of semantics. The solution binds the objects along with other related knowledge domains to the numerical processing to facilitate the detection of geometries and then uses experts’ inference rules to annotate them. The solution was tested within the prototypical application of the research project “Wissensbasierte Detektion von Objekten in Punktwolken für Anwendungen im Ingenieurbereich (WiDOP)”. The flexibility of the solution is demonstrated through two entirely different USE Case scenarios: Deutsche Bahn (German Railway System) for the outdoor scenarios and Fraport (Frankfort Airport) for the indoor scenarios. Apart from the difference in their environments, they provide different conditions, which the solution needs to consider. While locations of the objects in Fraport were previously known, that of DB were not known at the beginning. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Plane circular targets are widely used within calibrations of optical sensors through photogrammetric set-ups. Due to this popularity, their advantages and disadvantages are also well studied in the scientific community. One main disadvantage occurs when the projected target is not parallel to the image plane. In this geometric constellation, the target has an elliptic geometry with an offset between its geometric and its projected center. This difference is referred to as ellipse eccentricity and is a systematic error which, if not treated accordingly, has a negative impact on the overall achievable accuracy. The magnitude and direction of eccentricity errors are dependent on various factors. The most important one is the target size. The bigger an ellipse in the image is, the bigger the error will be. Although correction models dealing with eccentricity have been available for decades, it is mostly seen as a planning task in which the aim is to choose the target size small enough so that the resulting eccentricity error remains negligible. Besides the fact that advanced mathematical models are available and that the influence of this error on camera calibration results is still not completely investigated, there are various additional reasons why bigger targets can or should not be avoided. One of them is the growing image resolution as a by-product from advancements in the sensor development. Here, smaller pixels have a lower S/N ratio, necessitating more pixels to assure geometric quality. Another scenario might need bigger targets due to larger scale differences whereas distant targets should still contain enough information in the image. In general, bigger ellipses contain more contour pixels and therefore more information. This supports the target-detection algorithms to perform better even at non-optimal conditions such as data from sensors with a high noise level.

In contrast to rather simple measuring situations in a stereo or multi-image mode, the impact of ellipse eccentricity on image blocks cannot be modeled in a straight forward fashion. Instead, simulations can help make the impact visible, and to distinguish critical or less critical situations. In particular, this might be of importance for calibrations, as undetected influence on the results will affect further projects where the same camera will be used. This paper therefore aims to point out the influence of ellipse eccentricities on camera calibrations, by using two typical calibration bodies: planar and cube shaped calibration. In the first step, their relevance and influence on the image measurements, object- and camera geometry is shown with numeric examples. Differences and similarities between both calibration bodies are identified and discussed. In the second step, practical relevance of a correction is proven in a real calibration. Finally, a conclusion is drawn followed by recommendations to handle ellipse eccentricity in the practice.

Abstract.  Accurate recognition of airborne pollen taxa is crucial for understanding and treating allergic diseases which affect an important proportion of the world population. Modern computer vision techniques enable the detection of discriminant characteristics. Apertures are among the important characteristics which have not been adequately explored until now. A flexible method of detection, localization, and counting of apertures of different pollen taxa with varying appearances is proposed. Aperture description is based on primitive images following the bag-of-words strategy. A confidence map is estimated based on the classification of sampled regions. The method is designed to be extended modularly to new aperture types employing the same algorithm by building individual classifiers. The method was evaluated on the top five allergenic pollen taxa in Germany, and its robustness to unseen particles was verified.

This paper documents the formulation of an international, interdisciplinary study, on a concerted European level, to prepare an innovative, reliable, independent and global knowledge base facilitating the use of today’s and future optical measuring techniques for the documentation of  cultural heritage. Cultural heritage professionals, color engineers and scientists share similar goals for the documentation, curation, long-term preservation and representation of cultural heritage artifacts. Their focus is on accuracy in the digital capture and remediation of artefacts through a range of temporal, spatial and technical constraints. A shared vocabulary to interrogate these shared concerns will transform mutual understanding and facilitate an agreed movement forward in cultural heritage documentation here proposed in the work of the COST Action Color and Space in Cultural Heritage (COSCH). The goal is a model that captures the shared concerns of professionals for a standards-based solution with an organic Linked Data model. The knowledge representation proposed here invokes a GUI interface for non-expert users of capture technologies, facilitates, and formulates their engagement with key questions for the field.

Constant technological progress results in new possibilities to produce reliable and rich spatial data of cultural heritage objects. In order to make optimal use of these capabilities, it is important to identify and name the information required to best serve the reasoning processes in these application fields. Correspondingly it is necessary to know about the characteristics of digitization techniques producing the content adapted to the needs of the applications. Due to the considerable complexity of instruments and processes producing the data, it is helpful to have a clear structure which relates the capabilities of the instruments to the requirements of the applications. This paper addresses this topic and shows a way of structuring spatial techniques as well as how this structure can be related to applications in the field of cultural heritage.

Due to the increasing availability of large unstructured point clouds obtained from laser scanning and/or photogrammetric data, there is a growing demand for automatic processing methods. Given the complexity of the underlying problems, several new methods try to using semantic knowledge in particular for supporting object detection and classification. In this paper, we present a novel approach which makes use of advanced algorithms to benefit from intelligent knowledge management strategies for the processing of 3D point clouds and for object classification in scanned scenes. In particular, our method extends the use of semantic knowledge to all stages of the processing, including the guidance of the 3D processing algorithms. The complete solution consists in a multi-stage iterative concept based on three factors: the modelled knowledge, the package of algorithms, and the classification engine. Two case studies illustrating our approach are presented in this paper. The studies were carried out on scans of the waiting area of an airport and along the tracks of a railway. In both cases the goal was to detect and identify objects within a defined area. With our results we demonstrate the applicability of our approach.

Automatische Detektion und Klassifikation von Objekten in Punktwolken unter Nutzung mehrschichtiger Semantik. Infolge der zunehmenden Verfügbarkeit großer unstrukturierter Punktwolken aus Laserscanning und Photogrammetrie entsteht wachsender Bedarf für automatisierte Auswerteverfahren. Angesichts der häufig hohen Komplexität der in den Punktwolken enthaltenen Objekte stoßen rein datengetriebene Ansätze an ihre Grenzen. Es entstehen vermehrt Konzepte, die auf verschiedene Weise auch Gebrauch von der Semantik machen. Semantik und Algorithmik sind dabei oft eng miteinander verwoben und führen zu Limitationen in Art und Umfang der nutzbaren Semantik. Mit der vorgestellten Lösung werden Algorithmik und Semantik klar getrennt und mit den exakt auf diese Domänen zugeschnittenen Werkzeugen behandelt. Deren prozedurale Verknüpfung führt dann zu einem neuen Verarbeitungskonzept, das eine nach unserem Kenntnisstand bislang nicht erreichte Flexibilität und Vielseitigkeit in der Nutzung unterschiedlichster Semantiken besitzt und auch die Steuerung der Algorithmen integriert. Die iterative Gesamtlösung fußt auf drei Säulen, nämlich dem modellierten Wissen, dem Pool der Algorithmen und dem Identifikationsprozess. Erreichbare Resultate werden an zwei Beispielen dokumentiert. Ein Beispiel befasst sich mit der Analyse von Punktwolken aus dem Bereich der Lichtraumvermessung an Bahntrassen, das zweite mit Räumlichkeiten in einem Flughafen. In beiden Fällen müssen bestimmte Objektarten aufgefunden und klassifiziert werden.

The emergence of the Semantic Web and its underlying knowledge technologies has brought changes in data handling. Transferring expert knowledge to machines through knowledge formalization provides us the required support in managing huge datasets like the information in the World Wide Web. In the field of geospatial technology semantic technologies not only entail the capability to achieve higher degree of data integration but also infer semantics to discover new and hidden knowledge. This is of particular interest in the field of archaeology, where complex interrelations among heterogeneous datasets exist. Although researches on semantics are active areas in geospatial communities, their initial use is mainly for spatial data integration. This article tries to go one step further and imply semantics for spatial knowledge discovery through spatial built-ins within SWRL and SPARQL. The work resembles the approach of the Open Geospatial Consortium (OGC) to define standards for ­GeoSPARQL.

In this paper we present a novel approach for 3D point cloud processing with the aim of annotating objects in a scanned scene. Our method is based on human cognition to guide the 3D processing algorithms and uses semantic knowledge to manage data and identify immediate situation-dependent objectives. In particular, we have built a system that allows an automatic and flexible selection of algorithms. The selection strategy exploits knowledge to identify the geometrical features to be detected as well as the objects to be annotated at each stage of the 3D processing of the point cloud.

Over the last few years, formal ontologies has been suggested as a solution for several engineer problems, since it can efficiently replace standard data bases and relational one with more flexibility and reliability. In fact, well designed ontologies own lots of positive aspects, like those related to defining a controlled vocabulary of terms, inheriting and extending existing terms, declaring a relationship between terms, and inferring relationships by reasoning on existent ones. Ontologies are used to represent formally the knowledge of a domain where the basic idea was to present knowledge using graphs and logical structure to make computers able to understand and process it, (Boochs, et al., 2011). As most recent works, the tendency related to the use of semantic has been explored, (Ben Hmida, et al., 2010) (Hajian, et al., 2009) (Whiting, 2006) where the automatic data extraction from 3D point clouds presents one of the new challenges, especially for map updating, passenger safety and security improvements. However such domain is characterized by a specific vocabulary containing different type of object. In fact, the assumption that knowledge will help the improvement of the automation, the accuracy and the result quality is shared by specialists of the point cloud processing.

We present a novel method to register multispectral acquisitions on a 3D model. The method is based on the external tracking of the acquisition systems using close-range photogrammetric techniques: multiple calibrated cameras simultaneously observe the successive acquisition systems in use. The views from these cameras are used to precisely determine the position of each acquisition system. All datasets can then be projected in the same coordinate system. The registration is thus independent from the quality and content of the data. This method is well suited to the study of cultural heritage or any other application where we do not wish to place targets on the object. We describe the method and the simulation pipeline used to find an adequate setup for two case studies.

Buddhist stone inscriptions of the 8th to 12th centuries ad are important cultural assets of China that need to be documented, analysed and interpreted archaeologically, art-historically and linguistically. On the one hand, such Buddhist stone inscriptions have to be conserved for future generations, but on the other hand, further possibilities for analysing the data could be achieved if the inscriptions were made accessible to a wider community, for instance, for understanding of the historical growth of Buddhism in China. In this paper, innovative techniques for the documentation of stone inscriptions located in the province of Sichuan, in the south-west of China, are demonstrated. The tasks to be performed include capturing the stone inscriptions by using high precision measuring techniques to generate copies of the original inscriptions, together with processing of the data enabling improvement in the legibility of characters and thus aiding the interpretation of the inscriptions. The concept and features of image processing as applied to the captured inscriptions are outlined. In order to present the outcome to as many people as possible and to allow individual interpretations of the results of the stone inscription reconstruction, their current interpretation and additional 2D/3D maps are published within an interactive web platform.

Object reconstruction is an important task in many fields of application as it allows to generate digital representations of our physical world used as base for analysis, planning, construction, visualization or other aims. A reconstruction itself normally is based on reliable data (images, 3D point clouds for example) expressing the object in his complete extent. This data then has to be compiled and analyzed in order to extract all necessary geometrical elements, which represent the object and form a digital copy of it. Traditional strategies are largely based on manual interaction and interpretation, because with increasing complexity of objects human understanding is inevitable to achieve acceptable and reliable results. But human interaction is time consuming and expensive, why many researches has already been invested to use algorithmic support, what allows to speed up the process and to reduce manual work load.

Presently most of such supporting algorithms are datadriven and concentrate on specific features of the objects, being accessible to numerical models. By means of these models, which normally will represent geometrical (flatness, roughness, for example) or physical features (color, texture), the data is classified and analyzed. This is successful for objects with low complexity, but gets to its limits with increasing complexness of objects. Then purely numerical strategies are not able to sufficiently model the reality.

Therefore, the intention of our approach is to take human cognitive strategy as an example, and to simulate extraction processes based on available human defined knowledge for the objects of interest. Such processes will introduce a semantic structure for the objects and guide the algorithms used to detect and recognize objects, which will yield a higher effectiveness. Hence, our
research proposes an approach using knowledge to guide the algorithms in 3D point cloud and image processing.

This paper presents our experience regarding the creation of 3D semantic facility model out of unorganized 3D point clouds. Thus, a knowledge-based detection approach of objects using the OWL ontology language is presented. This knowledge is used to define SWRL detection rules. In addition, the combination of 3D processing built-ins and topological Built-Ins in SWRL rules aims at combining geometrical analysis of 3D point clouds and specialist’s knowledge. This combination allows more flexible and intelligent detection and the annotation of objects contained in 3D point clouds. The created WiDOP prototype takes a set of 3D point clouds as input, and produces an indexed scene of colored objects visualized within VRML language as output. The context of the study is the detection of railway objects materialized within the Deutsche Bahn scene such as signals, technical cupboards, electric poles, etc. Therefore, the resulting enriched and populated domain ontology, that contains the annotations of objects in the point clouds, is used to feed a GIS system.

3D objects modelling from 2D images is a major task in many application fields including robotics, virtual and augmented reality, and entertainment. According to the equipment used to acquire and process data, a reconstruction process can be based on laser or optical scanners or on digital images. Laser scanner provides a highly detailed and accurate representation of even complex surface shapes but generally, they are expensive, the data processing consumes much time and requires expert interaction with the machine. On the other hand, image based multi-view stereovision techniques provide nowadays an exciting alternative for 3D scene reconstruction because images can be easily obtained. Given a set of 2D images, we propose a novel approach for 3D urban scene reconstruction with low cost by extending unstructured spatial data normally generated by stereovision approaches by linear structures found in the same images. Our suggested system try to resolve two proposed issues: (1) The generation of dense 3D point clouds from 2D images (2) The integration of the available structured 2D data for the improvement of the detection/reconstruction of urban structures.

This paper presents a knowledge-based detection of objects approach using the OWL ontology language, the Semantic Web Rule Language, and 3D processing built-ins aiming at combining geometrical analysis of 3D point clouds and specialist’s knowledge. Here, we share our experience regarding the creation of 3D semantic facility model out of unorganized 3D point clouds. Thus, a knowledge-based detection approach of objects using the OWL ontology language is presented. This knowledge is used to define SWRL detection rules. In addition, the combination of 3D processing built-ins and topological Built-Ins in SWRL rules will allows more flexible and intelligent detection, and the annotation of objects contained in 3D point clouds. The created WiDOP prototype takes a set of 3D point clouds as input, and produces as output a populated ontology corresponding to an indexed scene visualized within VRML language. The context of the study is the detection of railway objects materialized within the Deutsche Bahn scene such as signals, technical cupboards, electric poles, etc. Thus, the resulting enriched and populated ontology, that contains the annotations of objects in the point clouds, is used to feed a GIS system or an IFC file for architecture purposes.

Bild- und Scandaten verfügen über komplementäre Eigenschaften, sodass ihre Fusion einen Informationsgewinn verspricht. Ihre gemeinsame Nutzung erfordert jedoch die Herstellung einer Korrespondenz zwischen den heterogenen Datentypen. Diese lässt sich mit natürlichen Objektinformationen nur schwer realisieren, insbesondere wenn die relative Orientierung von Kamera und Scanner unbekannt ist. Zur Verknüpfung der Bild- und Scandaten sowie zur Registrierung der Scandaten sollen deshalb spezielle Passkörper zum Einsatz kommen.

Buddhistic stone inscriptions (8th-12th centuries) are important cultural assets of China which need to be documented, analyzed, interpreted and visualized archaeologically, art-historically and text-scientifically. On one hand such buddhistic stone inscriptions have to be conserved for future generations but on the other hand further possibilities for analyzing the data could be enabled when the inscriptions would be accessible to a larger community, for instance the understanding of the historical growth of Buddhism in China could In this article we show innovative techniques for the documentation of stone inscriptions located in the province of Sichuan - southwest of china. The tasks to be performed comprise capturing of stone inscriptions by using high precision measuring techniques to generate copies of the original inscriptions and the processing of the data enabling the improvement of the legibility of characters and thus supporting the interpretation of the inscriptions. We show the concept and features of the image processing applied on the captured inscription. In order to present the outcome to a large community and to allow individual interpretations, the results of the stone inscription reconstruction, the interpretation and additional 2D / 3D maps are published within an interactive web platform.

The reconstruction of 3D objects from point clouds and images is a major task in many application fields. The processing of such spatial data, especially 3D point clouds from terrestrial laser scanners, generally consumes time and requires extensive interaction between a human and the machine to yield a promising result. Presently, algorithms for an automatic processing are usually datadriven and concentrate on geometric feature extraction. Robust and quick methods for complete object extraction or identification are still an ongoing research topic and suffer from the complex structure of the data, which cannot be sufficiently modelled by purely numerical strategies. Therefore, the intention of our approach is to take human cognitive strategy as an example, and to simulate these processes based on available knowledge for the objects of interest. Such processes will first, introduce a semantic structure for the objects and second, guide the algorithms used to detect and recognize objects, which will yield a higher effectiveness. Hence, our research proposes an approach using knowledge to guide the algorithms in 3D point cloud and image processing.

Modern optical measuring systems are able to record objects with high spatial and spectral precision. The acquisition of spatial data is possible with resolutions of a few hundredths of a millimeter using active projection-based camera systems, while spectral data can be obtained using filter-based multispectral camera systems that can capture surface spectral reflectance with high spatial resolution. We present a methodology for combining data from these two discrete optical measuring systems by registering their individual measurements into a common geometrical frame. Furthermore, the potential for its application as a tool for the non-invasive monitoring of paintings and polychromy is evaluated. The integration of time-referenced spatial and spectral datasets is beneficial to record and monitor cultural heritage. This enables the type and extent of surface and colorimetric change to be precisely characterized and quantified over time. Together, these could facilitate the study of deterioration mechanisms or the efficacy of conservation treatments by measuring the rate, type, and amount of change over time. An interdisciplinary team of imaging scientists and art scholars was assembled to undertake a trial program of repeated data acquisitions of several valuable historic surfaces of cultural heritage objects. The preliminary results are presented and discussed.

This paper presents a photogrammetric solution for the tracking of a robot head. First the need and aims of such a tracking process are explained, followed by a description of actual solutions and their restrictions. Then the potential of photogrammetric solutions for such purposes are outlined, followed by a detailed description of the system developed here. Finally, practical tests  are shown, underlining that the design and realization are able to hold the challenging aims and improve the absolute accuracy of a robot by a factor of 20.

Der zunehmende Einsatz des terrestrischen 3D-Laserscannings (TLS) für die Bereiche Bauwesen, Architektur und Archäologie liefert immer umfangreichere TLS-Punktmengen in immer kürzerer Messzeit vor Ort. Auf der Auswerteseite erfordern diese per se unstrukturierten Datenmengen in zunehmendem Maße Softwaremodule, die ebenso eine zügige und bequeme, somit auch effiziente, Verarbeitung erlauben. In diesem Artikel werden verschiedene Konzepte und Ansätze zur Konstruktion von halb- und vollautomatisierten Auswertealgorithmen für 3D-Punktmengen vorgestellt. Dabei werden die zu bewältigenden Aufgabenstellungen, wie z.B. Kugel- und Gebäuderekonstruktion, auf spezielle exakt formulierte Detailprobleme begrenzt, sodass das Ziel eines automatisierten Auswertungsprozesses auch in der Praxis erreicht wird. Die Algorithmen arbeiten entweder auf rein geometrischer Basis oder unter Zuhilfenahme von Vorwissen in Form einer Ontologie. Die Verarbeitungsprozesse sind sowohl daten- als auch modellgetrieben. Die Anwendungsbeispiele beschäftigen sich u.a. mit der Passkugelextraktion, der Querprofilableitung bei Schienenverkehrsanlagen und der Modellierung von Gebäudeinnenräumen. Teilweise lassen sich die dargestellten Lösungen durch einfache Variation der Eingangsparameter auf vergleichbare Anwendungsbereiche übertragen.

This paper shows the potential to improve the absolute positional accuracy of a robot guided effector when applying photogrammetric strategies. First the need and aims of such a tracking process are explained, followed by a description of actual solutions and their restrictions. Then the potential of photogrammetric solutions for such purposes are outlined, followed by a detailed description of the system developed here. Finally, practical tests are shown, underlining that the design and realization are able to hold the challenging aims and improve the absolute accuracy of a robot by a factor of 20.

Cet article présente une méthode de reconstruction 3D de bâtiment à partir de nuages de points provenant de la mesure d’un scanner laser 3D. L’objectif est d’avoir, au final, une définition sémantique associée au modèle géométrique reconstruit afin d’être exploitable rapidement dans les logiciels CAO/DAO. Cette méthode se fonde sur l’idée qu’il est possible d’améliorer la reconstruction d’une scène 3D à partir d’un nuage de points de manière automatique, si le contexte sémantique de la scène est défini. Pour atteindre ces objectifs, les recherches entreprises depuis plusieurs années sont pluridisciplinaires. En effet, les techniques de reconstruction 3D font appel aux méthodes de vision artificielle de l’équipe M2D+ du laboratoire Le2i situé à Dijon et de l’institut de recherche appliquée i3mainz situé à Mayence en Allemagne. Concernant la partie gestion de la connaissance, celle-ci fait appel aux techniques des systèmes d’information et bases de données de l’équipe SISI du laboratoire Le2i, située également à Dijon.
 

Shifting from conventional approaches to an unusual approach in industrial archaeology, we suggest the use of a web platform based on semantic web technologies and knowledge management. This platform is used to store data during the excavation process and to manage knowledge acquired during the identification process of the findings. The principle of our approach consists in using semantic annotations in order to have a semantic view on data sets. The shared ontology that defines an index on the semantic annotations allows us to build a global schema between data sources. This global schema allows annotating, indexing, searching and retrieving data and documents.

Shifting from conventional approaches to an unusual approach in industrial archaeology, we suggest the use of a web platform based on semantic web technologies and knowledge management. This platform is used to store data during the excavation process and to manage knowledge acquired during the identification process of the findings. The principle of our approach consists in using semantic annotations in order to have a semantic view on data sets. The shared ontology that defines an index on the semantic annotations allows us to build a global schema between data sources. This global schema allows annotating, indexing, searching and retrieving data and documents.

Beschrieben wird ein aktives stereoskopisches Messkonzept zur Rekonstruktion von 3DObjektgeometrien. Durch automatische Adaption des projizierten Musters erfolgt dabei eine Anpassung der Punktdichte an die Objektgeometrie bereits während der Erfassung. Das Resultat des Prozesses ist ein optimiertes 3D-Model, welches das vermessene Objekt mit einem Minimum an Punkten beschreibt. Es wird gezeigt, dass mit der von uns entwickelten Methode ein derart optimiertes Model ohne Genauigkeitseinbußen gewonnen werden kann.

Das Institut ist als wissenschaftliche Einrichtung der Lehreinheit Geoinformatik und Vermessung der Fachhochschule Mainz mit der Wahrnehmung von Aufgaben im Bereich der angewandten Forschung und Entwicklung sowie des Technologietransfers im fachlichen Umfeld der Geoinformatik und Vermessung beauftragt. Der größte Teil der Projekte befasst sich mit der Gewinnung, Verarbeitung und Visualisierung raumbezogener Daten verschiedenartigster Objekte.

As it is widely known documentation is an important issue within the tasks of conservation, preservation and restoration of Cultural Heritage objects. In this context high-tech measuring methods which, at the same time, are located in the low-cost price segment, are of special interest. In this paper a special solution is presented, which preserves the potential of state-of-the-art photogrammetry and is simple enough to be used by non-technical experts on their own. The design of the system enables, e.g., scientists of the humanities to benefit from modern 3D measuring methods in their daily work without needing permanent support by technical professionals. The system consists of off-the-shelf digital cameras which actually have reached a high level of resolution, of image quality and of functionality, all at a reasonable price. Ease of use for measuring purposes is guaranteed by mounting one or two cameras on a specially developed space bar. The corresponding evaluation software allows for stereo-viewing on standard PC hardware, for various methods of stereophotogrammetric model referencing, for object digitizing as vector features, for data export as CAD data, for production of orthophotos and of true-scale object representations of curved surfaces. Two projects are reported for illustration of the system’s application. The first project deals with the documentation of 500 caves in the Ukrainian area of Crimea, the second one gives an example for the application in the field of preservation of historical monuments in Germany. In both projects the stereophotogrammetric system was used as an integrated part within the full spectrum of modern metrology methods, comprising laser scanning, tacheometry, GPS and more.

In this paper we show a solution dedicated to measure spatial contours by means of multiple cameras. The contours allow to derive position and orientation, if necessary, of objects which have to be measured very precisely. The use of multiple cameras makes the system very flexible and robust. Set up, processing tasks and results of the system are presented.

Introduced at IWAA 2004, the conceptual design of the alignment system RALF, Remote Alignment on the Fly, has been advanced in the past two years. The goal of RALF is to provide high-precision survey and alignment at inaccessible areas of  FAIR, the new international accelerator 'Facility for Antiproton and Ion Research' at GSI, Darmstadt. A photogrammetric approach was chosen for this purpose, facing problems and limitations like high radiation, little space and denial of any human access to the affected areas. This paper will present the status quo of the concept and give an overview of the previous work. This includes the development of a basic concept, evaluation of camera specifications and geometric camera tests. With regard to the expected radiation environment investigations concerning radiation hardness of CCDs were carried out as well as practical camera tests at radioactive conditions. Furthermore simulations of potential camera configurations have been accomplished and possible constraints for the accelerator design have been evaluated. A RALF test installation under realistic conditions is planned for the upcoming months. First parts of FAIR will be commissioned around 2010.

Digital reconstruction of archaeological objects may serve for different purposes and accordingly vary in the information provided. Simple web-based visualisations primarily need textural data combined with more or less accurate spatial geometry, classical documentations require complete and precise 3d-models allowing to eventually rebuild the object in case of damage, whereas basic research to the object itself, the history of its edification, the origin of the material used and the analysis of exiting damages demands a maximum of textural and geometrical information. In correspondence to these aims techniques for the data collection have to be selected, which will result in higher effort and higher demands to performance and versatility when more complex reconstructions are needed.

Looking at the actual technological progress, 3D-scanning, both structured light and laser based, and digital photogrammetry, for example, are providing possibilities to collect maximal information at a large spectrum. On the other hand, the potential of these new technologies sometimes will be overestimated, whereas effort and need for an adopted processing of data and a customised use of instruments often is  underestimated. If therefor seems necessary to give a look into an interdisciplinary project of historians and surveyors dedicated to evaluate  he value of these new sensing technologies.

A solution for industrial inspection purposes will be shown. The conception is based on digital colour images taken from numerous perspectives around the object to be controlled. The process of image orientation is simplified and improved by the use of spatial reference objects. In contrast to conventional planar targets they are visible from all views and allow a better concatenation of the images. In addition, they can introduce a scale information what simplifies preparatory actions to be done within object space and can contribute with their spatial shape. For the inspection the object will be marked by a laser projection system with point or line
patterns. The main aspects of the solution will be shown together with first test results.

Ein einfaches digitales Mess- und Aufnahmesystem für die Gewinnung der dreidimensionalen Geometrie von Objekten wird vorgestellt. Es beruht auf der Nutzung herkömmlicher Digitalkameras, die zu einem stereofähigen Aufbau verbunden werden und die Gewinnung direkt nutzbarer stereoskopischer Bildpaare erlauben. Die Auswertung der Stereobilder erfolgt an einem herkömmlichen, mit einer Stereographikkarte ausgerüstetem PC und gestattet die Erfassung von Objektgeometrien, die anschließend im DXF-Format abgespeichert werden.

A precise and true geometrical description of built objects is a fundamental base of most applications and is a must in the field of CAD. Such a geometry is in general expressed by a large number of individual points placed on the geo-object in consideration. The total quantity of these object points is called digital object model and is generated by a data collection process. Several different techniques are known for the collection of points and a very common one is the use of metric stereo images. Then special equipment like stereo plotters have to be used. The technology of such instruments has been developed permanently and has led to very productive and flexible computer assisted plotting systems. Recently, the big technological step to pure digital systems has been undertaken. However, the need of having the image information digitally available is a very demanding constraint for digital plotting systems. In many geo-applications images with a size of 23 by 23 cm2 have to be used, what results in very huge data sets. Therefore most digital plotting systems have special hard- and software components for the handling and display of such large images.

A photogrammetric evaluation system used for the precise determination of 3D-coordinates from blocks of large metric images will be presented. First, the motivation for the development is shown, which is placed in the field of processing tools for photogrammetric evaluation tasks. As the use and availability of metric images of digital type rapidly increases corresponding equipment for the measuring process is needed. Systems which have been developed up to now are either very special ones, founded on high end graphics workstations with an according pricing or simple ones with restricted measuring functionality. A new conception will be shown, avoiding special high end graphics hardware but providing a complete processing chain for all elementary photogrammetric tasks ranging from preparatory steps over the formation of image blocks up to the automatic and interactive 3D-evaluation within digital stereo models. The presented system is based on PC-hardware equipped with off the shelf graphics boards and uses an object oriented design. The specific needs of a flexible measuring system and the corresponding requirements which have to be met by the system are shown. Important aspects as modularity and hardware independence and their value for the solution are shown. The design of the software will be presented and first results with a prototype realised on a powerful PC-hardware configuration will be featured.

Der Beitrag stellt ein Verfahren vor, mit dessen Hilfe kubische Verknüpfungsobjekte in terrestrischen Messbildern erkannt und für die Orientierung der Messbilder eingesetzt werden können. Mit dem Verfahren wird das Ziel verfolgt, Einschränkungen hinsichtlich der Verknüpfung von Messbildern aufzuheben, die durch Sichtbarkeits- und Abbildungsprobleme bei den heute üblicherweise eingesetzten ebenen Signalen entstehen können. Dazu ist eine Lösung entwickelt worden, die in Farbbildern räumliche Signale erkennt und die Koordinaten der Targets für die Zuordnung und Bildorientierung bereitstellt. Im Beitrag wird das Vorgehen im Zusammenhang mit der Bildanalyse beschrieben und an Bildbeispielen
dokumentiert.

This paper introduces a new approach to edge-preserving smoothing of digital images. It is designed for an effective elimination of the image noise within digital images what is an essential step in applications like edge detection or image segmentation.
The approach presented here tries to overcome some of the disadvantages of existing smoothing filters and is conceived as an extension of the edge-preserving Maximum Homogeneity Neighbour Filter. The algorithm cleans up the image noise in the homogeneous areas, but preserves all image structures like edges or corners. It is shown that the new filter algorithm combines the advantageous features of different types of filters. The algorithm is not only applicable to grayscale images, but can be extended to multi-channel data, like color images too. The performance of the algorithm is achieved by a more complex and differentiating treatment of the image data compared to conventional concepts.

A stereo system designed and used for the measurement of 3D-coordinates within metric stereo image pairs will be
presented. First, the motivation for the development allowing to evaluate stereo images is shown. As the use and availability of digital metric images rapidly increases corresponding equipment for the evaluation and measuring process is needed. Systems which have been developed up to now are either very special ones, founded on high end graphics workstations with an according pricing or simple ones with restricted measuring functionality. A new conception will be shown, avoiding special high end graphics hardware but providing the measuring functionality required. The presented stereo system is based on PC-hardware equipped with a graphic board, uses an object-oriented programming technique and allows a connection to CAD packages like AutoCAD®. The specific conception of the system are shown. The key role of OpenGLTM is described, which supplies some elementary graphic functions, being directly supported by graphic boards and thus provides the performance needed. Further important aspects as modularity and hardware independence and their value for the solution are shown. Finally some sample functions concerned with image display and handling are presented in more detail.

In the following article a solution will be presented which is designed for the mutual geometric restitution of multispectral satellite images with subpixel accuracy. The chosen technique is found on an area based matching procedure using a local description of geometric distortions between the images. The process generates a grid of corresponding points covering the common area of the images. By means of this grid the content of the image to be referenced is transformed into the other one.
The procedure is applicable to data sets coming from multiple sensors or multiple dates. Motivation for the development, the structure of the algorithm and some results of practical examples are shown in the article.

The paper describes a procedure designed for the determination and visualization of surfaces from objects having full 3D-extent. The procedure is based on digital images captured from all sides around the object. The images will be triangulated and evaluated by means of image matching techniques, resulting in the generation of a large number of individual surface points densely scattered over the object surface. From this point field, the surface will be derived by triangulating all points into a TIN data structure. When the data structure is established, attribute information is incorporated, describing aspects being of interest for further usage of the data. Finally, the object surface will be visualized interactively, allowing for a user controlled inspection of the object. The visualization software is based on graphic standards and allows to display the object in 3D-perspectives which are generated from the object geometry, the visual information of the digital images and the coded presentation of the attribute values.

Die präzise und vollständige geometrische Erfassung von Objekten jeglicher Art wie auch deren Visualisierung und metrisch korrekte Abbildung ist eine der wesentlichen Aufgaben des Vermessungswesen (bzw. Geodäsie: Wissenschaft von der Ausmessung und Abbildung der Erdoberfläche). Üblicherweise hat man es dabei mit dem Objekt Erde (Geo-) und den damit fest verbundenen Teilen zu tun. Die Arbeitstechniken lassen sich allerdings auch auf andere Objekte anwenden, deren Oberfläche metrisch exakt beschrieben werden muß. Dies gilt besonders, wenn zur Vermessung digitale Datensätze gewonnen und rechnergestützte Verfahrenstechniken eingesetzt werden können.
Das vorliegende Beispiel dokumentiert einen Anwendungsfall, der die Einsatzmöglichkeiten von Vermessungsmethoden auf dem Gebiet der Archäologie beschreibt. Insbesondere stehen neue Techniken im Mittelpunkt, die hinsichtlich der Datenerfassung mit digitalen Bilddatensätzen und bezüglich der Objektpräsentation mit digitalen Vektor- und Rasterdatensätzen arbeiten. Die vollständige metrische und inhaltliche Beschreibung des Objektes erfolgt unter Verwendung eines digitalen Objektmodelles, das eine numerische Codierung der Oberfläche bedeutet. Zur Codierung wird eine große Menge einzelner, in der Oberfläche liegender Objektpunkte verwendet, deren Koordinaten vermessen und zusammen mit topologischer und Sachinformation in einer geeigneten Datenstruktur abgelegt werden.
Durch den so gewählten Lösungsweg wird die Anwendung auch zum typischen Beispiel für den Einsatz von Methoden der Geoinformatik, die benötigt werden, um Objekte in geeigneter Weise numerisch codieren zu können. Neben den zentralen Fragen der Datenstrukturen, der Verwaltung und des Umgangs mit objektbezogenen Daten spielen dabei natürlich auch die Vermessungstechniken eine wichtige Rolle, mit deren Hilfe die Objektbeschreibung gewonnen wird.
Der Aufsatz soll einen Einblick in diese Thematik geben und am konkreten Beispiel die verschiedenen Verfahrensschritte beschreiben.

The paper shows the conception and the achieved results for an archaelogical project aiming at the description and reproduction of a 3D surface body by means of digital photogrammetric techniques. Therein it is of main interest, to make full use of the 3D characteristic of the object surface. That means the collection, storage, organization and extraction of all discrete surface points as individual 3D elements within a unique 3D coordinate frame. The paper shows the actual stage of development, allowing for the complete description of the body surface and the use of the data for visualization purposes.

The data collection will be done by application of an image matching process onto each stereo model, resulting in a local Z=Z(X,Y) description. Due to the known geometric relation to the object bounded coordinate frame the local surface description can be transformed into a S=S(X,Y,Z) representation, taking some qualtity measures and geometrical parameters as additional attributes. Finally all transformed data sets will be merged into a unique object description, taking into account the supression or aggregation of individual point data within the overlapping areas.

As actual use of the surface data some graphical reproductions will be shown, using a selection process collecting all individual points which have to be considered, followed by the necessary geometric and radiometric transformations to achieve the desired surface representation.