23 research outputs found
IMAGE-2006 Mosaic: Product Description
This report describes the IMAGE-2006 mosaic products. Each product consists of a range of information layers grouped into three categories: base layers, mosaic layers, and quality layers. A mosaic product is available for each coverage and data/country region of interest combination.JRC.H.6-Digital Earth and Reference Dat
IMAGE-2006 Mosaic: Data Ingestion and Organisation v1.0
This report details how the IMAGE-2006 data has been ingested and organised in view of creating the IMAGE-2006 mosaic. In particular, it details the method developed for merging the two coverages (delivered on a country basis) into a unique pan-European coverage. The concept of data and country regions of interest is introduced and a method for compositing identical scenes originating from more than one country is detailed. The resulting reference coverage contains 3,533 unique scenes, starting from a total of 3,699 delivered scenes. While the number of received scenes matches those reported by the DLR/Metria report, it is not possible to check whether the received scenes actually match the IMAGE-2006 data set since to this date no master list is available.JRC.H.6-Digital Earth and Reference Dat
IMAGE-2006 Mosaic: Analysis of Image Footprints
This technical note presents an evaluation of the footprints of the IMAGE-2006 received imagery (as of April 15th 2008). The first coverage (2080 images) is nearly covering the full target territory (some small gaps, the largest one being the Porto Santo Island, Madeira, Portugal). The second coverage (1619 images) accounts for 96.5{\%} of the territory with Iceland and all Atlantic Islands missing plus a series of large gaps mainly in Scandinavia. Note that imagery was delivered as a union of country coverages rather than a truly European coverage. Consequently, some images overlapping two or more countries were delivered more than once. In addition, these duplicated images are not always exactly identical.JRC.H.6-Digital Earth and Reference Dat
Stochastic simulation to improve land-cover estimates derived from coarse spatial resolution satellite imagery = La simulation stochastique pour améliorer les estimations de la couverture des sols à partir d'images satellitales à résolution spatiale grossière
Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur
DEMIX Method Ranks COPDEM and FABDEM as Top 1'' Global DEMs
We present a practical approach to inter-compare a range of candidate digital
elevation models (DEMs) based on pre-defined criteria and statistically sound
ranking approach. The presented approach integrates the randomized complete
block design (RCBD) into a novel framework which has been named the DEMIX wine
contest. Ranking a collection of wines or a set of DEMs from a given set of
candidates leads to a mathematically similar problem. The method presented
provides a flexible, statistically sound and customizable tool for evaluating
the quality of any raster - in this case a DEM - by means of a ranking
approach, which takes into account a confidence level, and can use both
quantitative and qualitative criteria. The users can design their own criteria
for the quality evaluation in relation to their specific needs. The application
of the wine contest to six 1'' global DEMs, considering a wide set of study
sites, covering different morphological and landcover settings, highlights the
potentialities of the approach. We used a suite of criteria relating to the
differences in the elevation, slope, and roughness distributions compared to
reference DEMs aggregated from 1-5 m lidar-derived DEMs to 1 second DEM.
Results confirmed significant superiority of COPDEM and its derivative FABDEM
as the overall best 1'' global DEMs. They are slightly better than ALOS, and
clearly outperform NASADEM and SRTM, which are in turn much better than ASTER
Measurement of detector-corrected observables sensitive to the anomalous production of events with jets and large missing transverse momentum in pp collisions at √s=13 TeV using the ATLAS detector
Observables sensitive to the anomalous production of events containing hadronic jets and missing momentum in the plane transverse to the proton beams at the Large Hadron Collider are presented. The observables are defined as a ratio of cross sections, for events containing jets and large missing transverse momentum to events containing jets and a pair of charged leptons from the decay of a Z/γ ∗ boson. This definition minimises experimental and theoretical systematic uncertainties in the measurements. This ratio is measured differentially with respect to a number of kinematic properties of the hadronic system in two phase-space regions; one inclusive single-jet region and one region sensitive to vectorboson- fusion topologies. The data are found to be in agreement with the Standard Model predictions and used to constrain a variety of theoretical models for dark-matter production, including simplified models, effective field theory models, and invisible decays of the Higgs boson. The measurements use 3.2 fb−1 of proton–proton collision data recorded by the ATLAS experiment at a centre-of-mass energy of 13TeV and are fully corrected for detector effects, meaning that the data can be used to constrain new-physics models beyond those shown in this paper
Are You Being Served? Initial Findings of the Image2000 Website User Survey
Recently, the Image2000 user experience and satisfaction survey was made in order to identify and profile user communities, understand how the available data benefits the user communities and profile user requirements for future data holdings and services development. In this paper we present initial results and specifically we researched user communities, the perception of the availability of free spatial data, and the impact of the Image2000 access to data. The survey responses provided us with important information that could not be derived from server logs. It was possible to get a better idea of how users, especially European citizens became informed about the presence of geo-portals and the availability of public spatial information. A discussion is also made on the differences between 'users' and 'viewers' especially pertaining to the development of an automatic system to monitor usage patterns of people accessing publicly available geospatial data. An important conclusion of this survey is that most registered users were satisfied with the Image2000 data they downloaded and benefited from this access in some manner.JRC.H.6-Spatial data infrastructure
Adaptive Mosaicing: Principle and Application to the Mosaicing of Large Image Data Sets
Automatic image compositing of very large data sets is necessary for the creation of extensive mosaics based on high spatial resolution remotely sensed imagery. A novel morphological image compositing algorithm has been developed which adapts to salient images edges. This technique produces seam lines that are difficult to identify by the naked eye which is also a characteristic to measure the quality of the resulting seam line. This paper begins with a description of the methodology and results based on Landsat 7 TM imagery. It is also shown how updates to an already composited image data set can be easily made without having to reprocess the entire data set. Finally, ways of quantifying the quality of an automatically delineated cut line and future research directions are discussed.JRC.H.6-Spatial data infrastructure
A Mathematical Morphology Based Approach to Locating Spectral Endmembers
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 understanding of the spectral variability. Our ultimate
goal is to model the n-dimensional spectral space from the inside, out thereby providing a map of image spectral objects. The research presented in this paper are
initial findings applying mathematical morphology to imaging spectrometer data.
Mathematical morphology was applied in two ways: i) by measuring the morphological
hyperspectral scalar gradient at each pixel position using a structuring element
of predefined size and shape and ii) by determining whether this pixel falls within the
smallest enclosing hyperbox containing the pixels belonging to the structuring element
centred at this position. While the results are interesting in themselves, they
were unable to automatically provide the image endmembers. However, the results
provide a wealth of information on the local variations in spectral profiles which will
be used to model their behaviour within the spectral feature cloud.JRC.H.7-Land management and natural hazard
A First Look at Usage Patterns of Publicly Available Spatial Information
The development of Spatial Data Infrastructures (SDI) at global, national, and regional levels as well as the geo-portals to facilitate information sharing and access to web services has recently increased. Given the diverse geographical extents of these initiatives, from cross continental initiatives to neighbouring cities, one would expect to have access to solid evidence of the economic and social impacts of remotely accessible spatial data. Unfortunately, relatively few published studies have addressed this issue. Consequently, a study into the public use of freely available spatial data is necessary that is specifically focused on the experiences of the user. Our research into this topic will be based on the Image2000 (http://image2000.jrc.it/) and the European Soil (http://eusoils.jrc.it/) geo-portals. This paper summarises the initial results achieved during the first phase of our study and presents a plan of action for future studies aimed at filling the identified knowledge gaps.JRC.H.6-Spatial data infrastructure