Seamless Mosaicing of Very High Resolution Satellite Data at Continental Scale: A Case-Study for Big Data Science from Space

The seamless mosaicing of massive very high resolution imagery addresses several aspects related to big data from space. Data volume is directly proportional to the size the input data, i.e., order of several TeraPixels for a continent. Data velocity derives from the fact that the input data is delivered over several years to meet maximum cloud contamination constraints with the considered satellites. Data variety results from the need to collect and integrate various ancillary data for cloud detection, land/sea mask delineation, and adaptive colour balancing. This paper details how these 3 aspects of big data are handled and illustrate them for the creation of a seamless pan-European mosaic from 2.5m imagery.JRC.G.2 - Global security and crisis managemen

Quality Assessment of Hydrogeomorphological Features Derived from Digital Terrain Models

Digital terrain models (DTM) provide a model for representing the continuous earth elevation surface that can contain errors introduced by the main phases of generation and modelling. Uncertainty of the model is rarely considered by users. Assessment of uncertainty require information on the nature, amount and spatial structure of the errors. DTMs of di®erent original resolution were compared in order to assess the quality of derived hydrological and morphological features. SRTM dataset with resolution of 100m, DEM dataset mosaic from various sources with a resolution of 60m and ASTER derived dataset with a resolution of 30m were used. The error propagation was modelled with a stochastic approach. The probabilistic distribution of extracted hydrological features was drawn considering the spatial structure of errors in the datasets. The features considered were stream network and watershed divides net. The distribution of the Strahler order of the features was studied. An analysis of the overall probability of features extracted from variously prepared datasets was carried in order to get information on where is the most probable stream network or watershed divides net.JRC.H.6-Spatial data infrastructure

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: Automatic Seam Line Delineation

This report details the methodology developed for automatically composing the IMAGE-2006 imagery. The method is based on the automatic definition of seam lines in the regions where two or more images overlap. This is achieved thanks to morphological image compositing. A parallel algorithm enables the timely mosaicing of large data sets on a grid engine.JRC.H.6 - Digital Earth and Reference Dat

Contents lists available at ScienceDirect Pattern Recognition

journal homepage: www.elsevier.com/locate/pr Edge-preserving smoothing using a similarity measure in adaptive geodesi

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: Geometric and Radiometric Consistency of Input Imagery

Within their domain of overlap, two images may differ in both geometry and radiometry. Consequently, when they are mosaiced, these differences may reveal the position of the seam lines even if they follow salient image structures such as roads and streams. A pair of overlapping images is said to be consistent if they are in agreement to one another in both geometry and radiometry. In this report, the consistency is measured using correlation computations and linear regressions. Measurements are produced for all existing pairs of overlapping images (given the 3,699 IMAGE-2006 input images, there are 29,447 such pairs). The quality layers of the IMAGE-2006 mosaics rely directly on these measurements. Indeed, the agreement between any pair of adjacent pieces of the mosaic is determined by the consistency measurements calculated within the domain of overlap of the two images leading to these two mosaic pieces.JRC.H.6-Digital Earth and Reference Dat

The Alpha-Tree Algorithm

A new multi-scale graph-space connectivity framework is presented. It is based upon a measure of dissimilarity between adjacent elements of the graph that is used to construct a hierarchy of partitions. Connected components or partition cells are either preserved or rejected based on a set of attribute criteria that are enumerated through logical predicates. Enforcing attribute constraints generates a dichotomy of the partition hierarchy that can be used for image segmentation and other related applications. The framework is supported by an efficient union-find based algorithm that delivers a tree representation of the totally ordered set of graph-space partitions. It is referred to as the Alpha-Tree. The practical complexity of the algorithm is linear with respect to the number of pixels. Processes on the tree can be launched interactively and in real-time, from a separate module detached from the tree construction phase. The type of attributes and attribute thresholds can be set and adjusted interactively. Timed experiments on highly complicated and massive satellite image tiles are presented, complemented by comparisons to the standard method.JRC.G.2 - Global security and crisis managemen

Rubble detection from VHR aerial imagery data using differential morphological profiles

Rubble detection is a key element in post disaster crisis assessment and response procedures. In this paper we present an automated method for rapid detection and quantification of rubble from very high resolution (VHR) aerial imagery of urban regions. It is a two step procedure in which the input image is projected on to a hierarchical representation structure for efficient mining and decomposition. Image features matching the geometric and chromatic properties of rubble are fused into a rubble layer that can be re-adjusted interactively. The targeted objects are evaluated based on a density metric given by spatial aggregation. The method is tested on a small-scale exercise on the publically available aerial imagery of Port-au-Prince, Haiti. Performance and preliminary results are discussed.JRC.G.2-Global security and crisis managemen

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