Mathias Kneubühler

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The organised storage of spectral data described by metadata is important for long-term use and data sharing with other scientists. Metadata describing the sampling environment, geometry and measurement process serves to evaluate the suitability of existing data sets for new applications. There is a need for spectral databases that serve as repositories for(More)
The airborne ESA-APEX (Airborne Prism Experiment) hyperspectral mission simulator is described with its distinct specifications to provide high quality remote sensing data. The concept of an automatic calibration, performed in the Calibration Home Base (CHB) by using the Control Test Master (CTM), the In-Flight Calibration facility (IFC), quality flagging(More)
Directional effects in airborne imaging spectrometer (IS) data are mainly caused by anisotropic reflectance behavior of surfaces, commonly described by bi-directional reflectance distribution functions (BRDF). The radiometric and spectral accuracy of IS data is known to be highly influenced by such effects, which prevents consistent comparison of products.(More)
On August 18, 2002, the Hyperion hyperspectral imager onboard the EO-1 platform recorded data over an intensively used agricultural area in north western Switzerland, the Limpach Valley. The sensor’s 198 spectral bands between 400 and 2500 nm (Level 1B1) and a spatial resolution of 30 m bear the potential for both a detailed land use classification and an(More)
In spectrodirectional Remote Sensing (RS) the Earth's surface reflectance characteristics are studied by means of their angular dimensions. Almost all natural surfaces exhibit an individual anisotropic reflectance behaviour due to the contrast between the optical properties of surface elements and background and the geometric surface properties of the(More)
Almost all natural surfaces exhibit an individual anisotropic reflectance characteristic due to contrasting optical properties of surface elements and background as well as an uneven distribution of illuminated and shadowed areas. The bidirectional reflectance distribution function BRDF is a basic quantity which describes the reflectance characteristic.(More)
The spaceborne ESA-mission CHRIS/PROBA (Compact High Resolution Imaging SpectrometerProject for On-board Autonomy) provides hyperspectral and multidirectional data of selected targets spread over the world. While the spectral information content of CHRIS/PROBA data is able to assess the biochemistry of a vegetation canopy, the directional information can(More)
Field and laboratory goniometers are widely used in the remote sensing community to assess spectrodirectional reflection properties of selected targets. Even when the same target and goniometer system are used, field and laboratory results cannot directly be compared due to inherent differences, mainly in the illumination conditions since actual goniometers(More)
The organised storage of spectral data described by according metadata is important for long term use and data sharing with other scientists. The recently redesigned SPECCHIO system acts as a repository for spectral field campaign and reference signatures. An analysis of metadata space has resulted in a non-redundant relational data model and efficient(More)
This paper presents a water quality study performed on five small domestic ponds and one bayou of the Ganga river in the State of West Bengal, India. The concept of eutrophication is used to describe water quality by using chlorophyll as an indicator for the presence of algae in the water. During a field campaign in May 2003, reflectance spectra were(More)