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

A morphological algorithm for improving radio-frequency interference detection

A technique is described that is used to improve the detection of radio-frequency interference in astronomical radio observatories. It is applied on a two-dimensional interference mask after regular detection in the time-frequency domain with existing techniques. The scale-invariant rank (SIR) operator is defined, which is a one-dimensional mathematical morphology technique that can be used to find adjacent intervals in the time or frequency domain that are likely to be affected by RFI. The technique might also be applicable in other areas in which morphological scale-invariant behaviour is desired, such as source detection. A new algorithm is described, that is shown to perform quite well, has linear time complexity and is fast enough to be applied in modern high resolution observatories. It is used in the default pipeline of the LOFAR observatory.Comment: Accepted for publication in A&

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

MORPHOLOGICAL SPATIAL PATTERN ANALYSIS: OPEN SOURCE RELEASE

Abstract. The morphological segmentation of binary patterns provides an effective method for characterising spatial patterns with emphasis on connections between their parts as measured at varying analysis scales. The method is widely used for the analysis of landscape patterns such as those related to the fragmentation of forests or other natural land cover classes. This can be explained by its effectiveness at capturing the complexity of binary patterns and their connections by partitioning the foreground pixels of the corresponding binary images into mutually exclusive classes. While the principles of the method are conceptually simple, the definition of the classes relies on a series of advanced mathematical morphology operations whose actual implementation is not straightforward. In this paper, we propose an open source code for MSPA and detail its main components in the form of pseudo-code. We demonstrate its effectiveness for asynchronous processing of tera-pixel images and the synchronous exploratory analysis and rendering with Jupyter notebooks

Morphological feature extraction for statistical learning with applications to solar image data

Abstract: Many areas of science are generating large volumes of digital image data. In order to take full advantage of the high-resolution and high-cadence images modern technology is producing, methods to automatically process and analyze large batches of such images are needed. This involves reducing complex images to simple representations such as binary sketches or numerical summaries that capture embedded scientific information. Using techniques derived from mathematical morphology, we demonstrate how to reduce solar images into simple ‘sketch ’ representations and numerical summaries that can be used for statistical learning. We demonstrate our general techniques on two specific examples: classifying sunspot groups and recognizing coronal loop structures. Our methodology reproduces manual classifications at an overall rate of 90 % on a set of 119 magnetogram and white light images of sunspot groups. We also show that our methodology is competitive with other automated algorithms at producing coronal loop tracings and demonstrate robustness through noise simulations. 2013 Wile

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: 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