—Users of remotely sensed imagery are often faced with the need to stitch two or more overlapping scenes together. This is generally referred to as image composition and the outcome is a single image with no overlapping regions which is also called an image mosaic. The most difficult part of image composition however, is deciding where to place the cut line… (More)
1 Introduction Spatially distributed estimates of ecological variables are generally required for use in geographic information systems (GIS) and models when dealing with many environmental phenomena . In particular, the quality of GIS products depends often on local properties that vary in space. In this context, increased interest has been demonstrated… (More)
We present Ontop-spatial, a geospatial extension of the well-known OBDA system Ontop, that leverages the technologies of geospatial databases and enables GeoSPARQL-to-SQL translation. We showcase the functionalities of the system in real-world use cases which require data integration of different geospatial sources.
This paper is about an initiative to produce an INSPIRE compliant pan-European image data set of known spatial accuracy. Two major motivations are behind developing this product. One is to have a trusted reference for any other rasterised data which is already orthorectified or requires orthorectification. The other is to have a gap-free and seamless image… (More)
Spectral endmembers are needed in order to apply Spectral Mixture Analysis (SMA) based on imaging spectrometer data. Currently there are several techniques able to find image endmembers in N spectral dimensions and are wholly based on the spectral feature space. However, modelling only the outside 'hull' of the spectral scatter provides only a basic… (More)