Prof. Manfred Ehlers Profile

Prof. Manfred Ehlers

Director at Univ. Osnabrück

SPIE Involvement:

Editor | Author

Publications (23)

Proceedings Article | 25 October 2012 Paper

Integrated data processing of remotely sensed and vector data for building change detection

N. Sofina, M. Ehlers, U. Michel

Proc. SPIE. 8538, Earth Resources and Environmental Remote Sensing/GIS Applications III

KEYWORDS: Geographic information systems, Satellite imaging, Satellites, Earth observing sensors, Raster graphics, Feature extraction, Chlorine, Data processing, Remote sensing, Earthquakes

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Proceedings Article | 27 October 2011 Paper

Object-based change detection: dimension of damage in residential areas of Abu Suruj, Sudan

Timo Demharter, Ulrich Michel, Manfred Ehlers, Peter Reinartz

Proc. SPIE. 8181, Earth Resources and Environmental Remote Sensing/GIS Applications II

KEYWORDS: Image segmentation, Accuracy assessment, Software development, Algorithm development, Remote sensing, Satellites, Buildings, Aluminum, Analytical research, Image processing

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Proceedings Article | 27 October 2011 Paper

Object-based rapid change detection for disaster management

Holger Thunig, Ulrich Michel, Manfred Ehlers, Peter Reinartz

Proc. SPIE. 8181, Earth Resources and Environmental Remote Sensing/GIS Applications II

KEYWORDS: Algorithm development, Buildings, Remote sensing, Image segmentation, Accuracy assessment, Earthquakes, Floods, Vegetation, Earth observing sensors, Sensors

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Proceedings Article | 27 October 2011 Paper

Object-based detection of destroyed buildings based on remotely sensed data and GIS

Natalia Sofina, Manfred Ehlers, Ulrich Michel

Proc. SPIE. 8181, Earth Resources and Environmental Remote Sensing/GIS Applications II

KEYWORDS: Buildings, Raster graphics, Image segmentation, Geographic information systems, Earthquakes, Edge detection, Open source software, Computer programming, Algorithm development, Data processing

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Proceedings Article | 4 November 2010 Paper

Prototype application for web 3D routing in building

Manfred Ehlers, Ihab Hijazi

Proc. SPIE. 7840, Sixth International Symposium on Digital Earth: Models, Algorithms, and Virtual Reality

KEYWORDS: 3D modeling, Geographic information systems, Data modeling, Prototyping, Databases, Visualization, Visual process modeling, 3D visualizations, 3D applications, Network security

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Proceedings Article | 7 October 2009 Paper

Interpretability of TerraSAR-X fused data

Pablo Rosso, Manfred Ehlers, Sascha Klonus

Proc. SPIE. 7478, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IX

KEYWORDS: Image fusion, Image segmentation, Image resolution, Image classification, Earth observing sensors, High resolution satellite images, Synthetic aperture radar, Spatial resolution, Multispectral imaging, Data fusion

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Proceedings Article | 7 October 2009 Paper

From fuzzy and object based classification to fuzzy and object based uncertainty evaluation

Jochen Schiewe, Manfred Ehlers, Christoph Kinkeldey, Daniel Tomowski

Proc. SPIE. 7478, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IX

KEYWORDS: Fuzzy logic, Remote sensing, Data modeling, Classification systems, Quality measurement, Sensors, Data processing, Spatial resolution, Vegetation, Geoinformatics

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Proceedings Article | 14 October 2008 Paper

Multidirectional decomposition and directional contrast based remote sensing images fusion

Yan Na, Manfred Ehlers, Jie Meng, Zhe Yang

Proc. SPIE. 7110, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology VIII

KEYWORDS: Image fusion, Wavelet transforms, Remote sensing, Image resolution, Spatial resolution, Sensing systems, Visualization, Visual system, Image analysis, Image processing

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Proceedings Article | 10 October 2008 Paper

Quality assessment for multitemporal and multisensor image fusion

Manfred Ehlers, Sascha Klonus

Proc. SPIE. 7110, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology VIII

KEYWORDS: Image fusion, Multispectral imaging, Wavelets, Spatial resolution, Earth observing sensors, Image enhancement, High resolution satellite images, Visualization, Modulation transfer functions, Image resolution

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Proceedings Article | 12 November 2007 Paper

Contents correlation and genetic algorithm based remote sensing images fusion

Yan Na, Manfred Ehlers, Hongbin Ji, Lin Shi

Proc. SPIE. 6749, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology VII

KEYWORDS: Image fusion, Genetic algorithms, Multispectral imaging, Remote sensing, Image processing, Image analysis, Wavelet transforms, Principal component analysis, Optimization (mathematics), Earth observing sensors

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Proceedings Article | 3 October 2006 Paper

Visual perception-based different scale remote sensing images fusion with multiwavelet transform

Yan Na, Manfred Ehlers, Wanhai Yang

Proc. SPIE. 6366, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology VI

KEYWORDS: Image fusion, Visualization, Remote sensing, Wavelets, Landsat, Spatial resolution, Sensing systems, Wavelet transforms, Visual system, Earth observing sensors

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Proceedings Article | 3 October 2006 Paper

On image fusion and segmentation

Manfred Ehlers

Proc. SPIE. 6366, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology VI

KEYWORDS: Image segmentation, Image fusion, Image processing, Image resolution, Image classification, Data fusion, Data modeling, Spatial resolution, Image analysis, Multispectral imaging

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Proceedings Article | 29 October 2005 Paper

Semantic evaluation of high-resolution low-cost digital camera data for urban classification

Alexander Frangesch, Ansgar Greiwe, Manfred Ehlers

Proc. SPIE. 5983, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology V

KEYWORDS: Image segmentation, Digital imaging, Analog electronics, Image classification, Digital cameras, Cameras, Image fusion, Data fusion, Image resolution, Classification systems

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Proceedings Article | 29 October 2005 Paper

Adaptive remote sensing image fusion with multiwavelet transform

Yan Na, Manfred Ehlers, Wanhai Yang, Lin Shi

Proc. SPIE. 5983, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology V

KEYWORDS: Image fusion, Landsat, Remote sensing, Spatial resolution, Wavelet transforms, Principal component analysis, Wavelets, Multispectral imaging, Image processing, Earth observing sensors

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Proceedings Article | 22 October 2004 Paper

Spectral characteristics preserving image fusion based on Fourier domain filtering

Manfred Ehlers

Proc. SPIE. 5574, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IV

KEYWORDS: Image fusion, Image filtering, Transform theory, Image resolution, Data fusion, Linear filtering, Spatial resolution, Multispectral imaging, Optical filters, Earth observing sensors

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Proceedings Article | 22 October 2004 Paper

Segment-based classification algorithm For multisensor image data

Ansgar Greiwe, Manfred Ehlers

Proc. SPIE. 5574, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IV

KEYWORDS: Image segmentation, Spatial resolution, Image classification, Data fusion, Data modeling, Sensors, Library classification systems, RGB color model, Hyperspectral imaging, Image processing

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The motivation for data fusion is to reduce the limitations and uncertainties associated with data coming from a single sensor only. In the context of remotely sensed data the fusion is often performed by combining high spatial with high spectral resolution imagery at different levels. In contrast to pixel-based approaches like the IHS-transformation, in this paper we will focus on a fusion of data at the feature level. In high spatial resolution data the geometry of urban objects can be determined very accurately. But high spatial resolution data often contains low spectral information such as, for example, a three band RGB image. Thus, similar feature values for thematic classes like water, dark pavements or dark rooftops lead to classification errors. If hyperspectral data is used to classify urban materials, the definition of endmembers representing those materials is needed. The problem is that endmembers representing urban surface types are often the result of a mixture of spectral pure materials which leads to flat spectra. Consequently, those thematic endmembers can hardly be detected by standard algorithms like the Pixel Purity Index (PPI) so that standard classification procedures fail. In order to improve the classification process, our approach fuses hyperspectral data recorded by the HyMap sensor with high spatial resolution imagery (digital orthophotos) for a combined endmember selection, classification, and structural analysis. The endmember for the thematic classes will be determined in a semi-automatic process. After a segmentation of the high spatial resolution dataset the resulting segments will be used to detect those pixels in the hyperspectral data sets, which represent candidates for the definition of thematic endmembers. The endmembers are stored in a spectral library and are used for the classification of hyperspectral data. The segments in the high spatial resolution data will be processed based upon the classification of the hyperspectral dataset and the application of overlay rules.

Proceedings Article | 22 October 2004 Paper

Remote sensing image fusion with multiwavelet transform

Yan Na, Manfred Ehlers, Wanhai Yang

Proc. SPIE. 5574, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IV

KEYWORDS: Image fusion, Wavelet transforms, Principal component analysis, Spatial resolution, Remote sensing, Image enhancement, Multispectral imaging, Image processing, Wavelets, Earth observing sensors

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Proceedings Article | 13 February 2004 Paper

Fusion of multisensor remote sensing data for urban land cover classification

Ansgar Greiwe, Mathias Bochow, Manfred Ehlers

Proc. SPIE. 5239, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology III

KEYWORDS: Rutherfordium, Image segmentation, Spatial resolution, Remote sensing, Data fusion, Image resolution, Image classification, Image fusion, Geographic information systems, RGB color model

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The motivation for data fusion is to reduce the limitations and uncertainties associated with single sensor data. In the context of remotely sensed data this is often performed by combining images of high spatial resolution with those of high spectral resolution at different levels. In contrast to pixel-based approaches like Intensity-Hue-Saturation (IHS) or Principal Component (PC) we will focus on image fusion at feature level. The research of this paper was conducted within within the "HyScan" project which goal is to develop a GIS based analysis and mapping of surface characteristics in urban areas using hyperspectral images in combination with remote sensing data of very high spatial resolution. In most cases the classification of hyperspectral data is performed using methods like Spectral Angle Mapper (SAM) or Mixture Tuned Matched Filtering (MTMF). Reference spectra for those algorithms are stored in libraries which contain the spectra of pure materials so called endmembers. The problem is that endmembers that represent urban surface types often display a mixture of spectral pure materials and thus show flat spectra. As a result, those thematic endmembers can hardly be detected by standard algorithms like the Pixel Purity Index (PPI). As a consequence standard classification procedures fail. In order to improve the quality of results, we fuse hyperspectral data recorded by the DAIS sensor with high spatial resolution imagery (e.g. HRSC) for a combined endmember selection, classification, and structural analysis. After segmentation of the high spatial resolution data, appropriate thematic classes are manually defined. The resulting segments are used to detect a set of pure pixels in the hyperspectral data which represent thematic endmembers. The segments resulting from the spatial high resolution data are processed using the endmember abundances of the hyperspectral data through a combined classification. Method and initial results of our fusion method are presented for endmember selection and classification of urban surface characteristics.

Proceedings Article | 13 February 2004 Paper

Remote sensing for GIS applications: new sensors and analysis methods

Manfred Ehlers

Proc. SPIE. 5239, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology III

KEYWORDS: Remote sensing, Geographic information systems, Sensors, Satellites, Image resolution, Imaging systems, Spatial resolution, Sensing systems, Geoinformatics, Earth observing sensors

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Proceedings Article | 23 January 2002 Paper

New remote sensing concepts for environmental monitoring

Manfred Ehlers, Ronald Janowsky, Monika Gaehler

Proc. SPIE. 4545, Remote Sensing for Environmental Monitoring, GIS Applications, and Geology

KEYWORDS: Remote sensing, Geographic information systems, Vegetation, Satellites, Scanners, Environmental monitoring, Imaging systems, Cameras, Geoinformatics, Earth observing sensors

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Proceedings Article | 30 December 1994 Paper

Determining uncertainties and their propagation in classified remotely sensed image-based dynamic change detection

Wenzhong Shi, Manfred Ehlers

Proc. SPIE. 2315, Image and Signal Processing for Remote Sensing

KEYWORDS: Probability theory, Image classification, Photovoltaics, Data processing, Visualization, 3D visualizations, Zirconium, Mathematical modeling, Earth observing sensors, Modeling

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Proceedings Article | 30 December 1994 Paper

High-precision geometric correction of airborne remote sensing revisited: the multiquadric interpolation

Manfred Ehlers, David Fogel

Proc. SPIE. 2315, Image and Signal Processing for Remote Sensing

KEYWORDS: Scanners, Image processing, Image registration, Photography, Remote sensing, Data modeling, Airborne remote sensing, Satellites, Visual process modeling, Digital imaging

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Proceedings Article | 17 August 1994 Paper

Modeling image interpretation in remote sensing through a virtual GIS shell (VGIS)

Manfred Ehlers, Hartmut Broesamle, Jochen Albrecht

Proc. SPIE. 2357, ISPRS Commission III Symposium: Spatial Information from Digital Photogrammetry and Computer Vision

KEYWORDS: Geographic information systems, Data modeling, Human-machine interfaces, Remote sensing, Image processing, Visualization, Image analysis, Data hiding, Systems modeling, Data processing

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Showing 5 of 23 publications

Proceedings Volume Editor (17)

SPIE Conference Volume | 10 January 2017

Earth Resources and Environmental Remote Sensing/GIS Applications VII

SPIE Conference Volume | 10 November 2015

Earth Resources and Environmental Remote Sensing/GIS Applications VI

SPIE Conference Volume | 21 November 2014

Earth Resources and Environmental Remote Sensing/GIS Applications V

SPIE Conference Volume | 11 November 2013

Earth Resources and Environmental Remote Sensing/GIS Applications IV

SPIE Conference Volume | 14 November 2012

Earth Resources and Environmental Remote Sensing/GIS Applications III

Showing 5 of 17 publications

Conference Committee Involvement (17)