Eberhard Gülch and Hardo Müller and Thomas Läbe, "Integration of Automatic Processes Into Semi-Automatic Building Extraction", In Proceedings of ISPRS Conference "Automatic Extraction Of GIS Objects From Digital Imagery". 1999.

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The modeling of three-dimensional objects is a current topic in digital photogrammetric research. The modeling of buildings in digital imagery or digital surface models involving automation processes has reached a level where it can compete with classical photogrammetric stereo measurements. There are many different ways on how to integrate automation. We describe our system and its automated features that support the operator in the adaption of parametric models to multiple overlapping images. There do exist tools to automate the measurement of heights, to automate the estimation of the form parameters or for the handling of building aggregates. With such tools we can reach about 20 seconds for the modeling of a volumetric primitive which is fully comparable to the currently used photogrammetric methods.

@inproceedings{Gulch1999Integration,
  author = {G\"ulch, Eberhard and M\"uller, Hardo and L\"abe, Thomas},
  title = {Integration of Automatic Processes Into Semi-Automatic Building Extraction},
  booktitle = {Proceedings of ISPRS Conference "Automatic Extraction Of GIS Objects From Digital Imagery"},
  year = {1999}
}

Eberhard Gülch and Hardo Müller and Thomas Läbe and Lemonia Ragia, "On the performance of semi-automatic building extraction", In Proceedings of ISPRS Commission III Symposium. Columbus, Ohio 1998.

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A Semi-Automatic Building Extraction system using two or more digitized overlapping aerial images has been enhanced by increased automation for the measurement of saddle-back-roof buildings, hip-roof buildings and boxes. All newly developed modules have been incorporated in the object oriented design of the system. The new methods consist of a ground-point and roof-top matching tool and a robust determination of shape parameters, like e.g. gutter length and width. The current performance of building extraction is quantitatively and qualitatively evaluated. We examine the increased efficiency using the automated tools, the success rate of individual modules and the overall success rate using a combination of methods. A methodology for quantitative comparison is tested on footprints of buildings from classical stereo measurements and from semi-automatic measurements. A qualitative comparison in 3D of multiple measurements of complete buildings is performed on three different datasets.

@inproceedings{Gulch1998performance,
  author = {G\"ulch, Eberhard and M\"uller, Hardo and L\"abe, Thomas and Ragia, Lemonia},
  title = {On the performance of semi-automatic building extraction},
  booktitle = {Proceedings of ISPRS Commission III Symposium},
  year = {1998}
}

Eberhard Gülch and Hardo Müller, "Virtuelle Staedte aus digitalen Bildern", In Proceedings of Virtual GIS. Rostock 1998.

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Der Übergang von der klassischen Photogrammetrie mit analogen Bildern zur Digitalen Photogrammetrie mit digitalen Bildern und der Automation von Messprozessen eröffnet vielfältige Möglichkeiten zur effizienten Erfassung von 3D-Information in urbanen Gebieten. Es ist ein zunehmender Bedarf an realen 3D-Daten für eine Vielfalt von Anwendungen zu beobachten. Diese reichen von Managementaufgaben in Stadtplanung und Städtebau bis hin zu Funknetzsimulationen, Werbung und Spieleindustrie. 3D-Stadtmodelle eignen sich nicht nur zur Analyse und Simulation, sondern auch zur computeranimierten Darstellung bis hin zur Virtuellen Realität. Das hier vorgestellte System wird zur geometrischen Modellierung aus Mono-, Stereo- oder mehrfachüberdeckenden Luftbildern eingesetzt. Verschiedene automatisierte Module unterstützen den Operateur. Neben einer detaillierten geometrischen Erfassung spielt die Visualisierung von Texturen eine immer größere Rolle. Mit dem hier vorgestellten System können orientierte Luft- und Nahbereichsaufnahmen gleichermaßen zur automatischen Texturierung von erfaßten 3D-Objektmodellen eingesetzt werden. Integraler Bestandteil ist eine Entzerrung und die Wahl der Texturelementgröße im Objektraum, womit verschiedene Detaillierungsgrade (Level-of-Detail) der virtuellen Darstellung erzeugt werden können.

@inproceedings{Gulch1998Virtuelle,
  author = {G\"ulch, Eberhard and M\"uller, Hardo},
  title = {Virtuelle Staedte aus digitalen Bildern},
  booktitle = {Proceedings of Virtual GIS},
  year = {1998}
}

Hardo Müller, "Object-oriented modeling for the extraction of geometry, texture and reflectance from digital images", In Proceedings of ISPRS Commission IV Symposium. Stuttgart, Germany 1998.

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A semi-automatic system for extracting topographic features is being migrated to an object-oriented design for better maintainability. For that purpose an object-oreinted model of the extracted objects and the extraction methods is required. Moreover an appropriate software component model for the exchange with other systems is needed. We have modeled a class hierarchy for objects, that can be semi-automatically extracted from digital images. These objects are characterized by geometric, textural and reflectance properties. We have classified the extraction methods and modeled the message transfer of an interactive extraction mehtod. The component technologies CORBA and JavaBeans (TM) were used to make the extracted objects and system components available for other systems. We found out that an access to the objcets of the Semi-Automatic System by operation calls allows a more flexible data transfer and control of the system than standard file transfer. Therefore Geographic Information Systems (GIS) should support appropriate software component models to co-operate optimally with interactive or semi-automatic feature extraction systems.

@inproceedings{Muller1998Object,
  author = {M\"uller, Hardo},
  title = {Object-oriented modeling for the extraction of geometry, texture and reflectance from digital images},
  booktitle = {Proceedings of ISPRS Commission IV Symposium},
  year = {1998}
}

Eberhard Gülch and Hardo Müller, "Object-oriented software design in semiautomatic building extraction", In Proceedings Integrating Photogrammetric Techniques with Scene Analysis and Machine Vision III. Orlando, USA 1997.

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Developing a system for semiautomatic building acquisition is a complex process, that requires constant integration and updating of software modules and user interfaces. To facilitate these processes we apply an object-oriented design not only for the data but also for the software involved. We use the Unified Modeling Language (UML) to describe the object-oriented modeling of the system in different levels of detail. We can distinguish between use cases from the users point of view, that represent a sequence of actions, yielding in an observable result and the use cases for the programmers, who can use the system as a class library to integrate the acquisition modules in their own software. The structure of the system is based on the Model-View-Controller (MVC) design pattern. An example from the integration of automated texture extraction for the visualization of results demonstrate the feasibility of this approach.

@inproceedings{Gulch1997Object,
  author = {G\"ulch, Eberhard and M\"uller, Hardo},
  title = {Object-oriented software design in semiautomatic building extraction},
  booktitle = {Proceedings Integrating Photogrammetric Techniques with Scene Analysis and Machine Vision III},
  year = {1997},
  doi = {10.1117/12.281043}
}

Hardo Müller, "Designing an object-oriented matching tool", In IAPRS: 3D Reconstruction and Modeling of Topographic Objects. Stuttgart 1997.

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A semiautomatic building extraction system has been extended by an automatic matching tool. It is used for an automatic measurement of building-heights and a semiautomatic determination of ground-heights. The object-oriented design of this matching tool gives the motivation for a design pattern of a general matching tool. This design pattern describes the object-oriented design of implementing several matching techniques within one system. It is able to be applied to several kinds of topographic objects, if a matching technique is known. We show as an example the implementation of a point matching tool, which uses the matching techniques Intensity Correlation and Gradient Correlation as a refinement of Feature Vector Matching.

@inproceedings{Muller1997Designing,
  author = {M\"uller, Hardo},
  title = {Designing an object-oriented matching tool},
  booktitle = {IAPRS: 3D Reconstruction and Modeling of Topographic Objects},
  year = {1997}
}