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A novel technique for the automatic detection of surface clutter returns in radar sounder data / Adam Ferro in IEEE Transactions on geoscience and remote sensing, vol 51 n° 5 Tome 2 (May 2013)
[article]
Titre : A novel technique for the automatic detection of surface clutter returns in radar sounder data Type de document : Article/Communication Auteurs : Adam Ferro, Auteur ; Alain Pascal, Auteur ; Lorenzo Bruzzone, Auteur Année de publication : 2013 Article en page(s) : pp 3037 - 3055 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] détection automatique
[Termes IGN] fouillis d'échos
[Termes IGN] image radar
[Termes IGN] Mars (planète)
[Termes IGN] méthode robuste
[Termes IGN] modèle numérique de surface
[Termes IGN] radargrammétrie
[Termes IGN] simulation
[Termes IGN] sondeur acoustique
[Termes IGN] surface du solRésumé : (Auteur) One of the most critical problems that affect the analysis of orbiting radar sounder data is the presence of spurious surface clutter returns. These are due to off-nadir echoes related to surface topography which may be detected as (or mask) actual subsurface targets. The detection of such returns is usually carried out manually through a visual comparison between actual radargrams and surface clutter simulations obtained using available digital elevation models (DEMs). This is an inherently subjective and time-consuming task, which may reduce the scientific return of the data. In this paper, we address this problem by proposing a novel technique for the automatic detection of surface clutter returns in radar sounder data. The proposed method is made up of three steps: 1) the simulation of surface clutter returns using available DEMs; 2) the automatic coregistration between radargrams and simulations; and 3) the extraction of surface clutter returns from the coregistered radargrams. The coregistration step is performed in two phases: 1) a coarse registration based on the detection of the first return line on both input radargrams and 2) a fine registration based on B-spline deformation. The proposed technique is robust to radargram geometric deformations (e.g., due to ionospheric effects) and allows the generation of different types of outputs (e.g., coregistered simulations, binary clutter maps, and false-color compositions) that can both greatly support the scientific community in the manual analyses of radar sounder data and drive the development of reliable automatic methods for high level processing. The effectiveness of the proposed method is proven on two data sets acquired on different areas of Mars by the Shallow Radar instrument. Numéro de notice : A2013-272 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2219315 En ligne : https://doi.org/10.1109/TGRS.2012.2219315 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32410
in IEEE Transactions on geoscience and remote sensing > vol 51 n° 5 Tome 2 (May 2013) . - pp 3037 - 3055[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2013051B RAB Revue Centre de documentation En réserve L003 Disponible The influence of scan mode and circle fitting on tree stem detection, stem diameter and volume extraction from terrestrial laser scans / Pyare Pueschel in ISPRS Journal of photogrammetry and remote sensing, vol 77 (March 2013)
[article]
Titre : The influence of scan mode and circle fitting on tree stem detection, stem diameter and volume extraction from terrestrial laser scans Type de document : Article/Communication Auteurs : Pyare Pueschel, Auteur ; Glenn J. Newnham, Auteur ; Gilles Rock, Auteur ; Thomas Udelhoven, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 44 - 56 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] détection automatique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Pseudotsuga menziesii
[Termes IGN] semis de points
[Termes IGN] tronc
[Termes IGN] volume (grandeur)Résumé : (Auteur) Terrestrial laser scanning (TLS) has been used to estimate a number of biophysical and structural vegetation parameters. Of these stem diameter is a primary input to traditional forest inventory. While many experimental studies have confirmed the potential for TLS to successfully extract stem diameter, the estimation accuracies differ strongly for these studies – due to differences in experimental design, data processing and test plot characteristics. In order to provide consistency and maximize estimation accuracy, a systematic study into the impact of these variables is required. To contribute to such an approach, 12 scans were acquired with a FARO photon 120 at two test plots (Beech, Douglas fir) to assess the effects of scan mode and circle fitting on the extraction of stem diameter and volume. An automated tree stem detection algorithm based on the range images of single scans was developed and applied to the data. Extraction of stem diameter was achieved by slicing the point cloud and fitting circles to the slices using three different algorithms (Lemen, Pratt and Taubin), resulting in diameter profiles for each detected tree. Diameter at breast height (DBH) was determined using both the single value for the diameter fitted at the nominal breast height and by a linear fit of the stem diameter vertical profile. The latter is intended to reduce the influence of outliers and errors in the ground level determination. TLS-extracted DBH was compared to tape-measured DBH. Results show that tree stems with an unobstructed view to the scanner can be successfully extracted automatically from range images of the TLS data with detection rates of 94% for Beech and 96% for Douglas fir. If occlusion of trees is accounted for stem detection rates decrease to 85% (Beech) and 84% (Douglas fir). As far as the DBH estimation is concerned, both DBH extraction methods yield estimates which agree with reference measurements, however, the linear fit based approach proved to be more robust for the single scan DBH extraction (RMSE range 1.39–1.74 cm compared to 1.47–2.43 cm). With regard to the different circle fit algorithms applied, the algorithm by Lemen showed the best overall performance (RMSE range 1.39–1.65 cm compared to 1.49–2.43 cm). The Lemen algorithm was also found to be more robust in case of noisy data. Compared to the single scans, the DBH extraction from the merged scan data proved to be superior with significant lower RMSE’s (0.66–1.21 cm). The influence of scan mode and circle fitting is reflected in the stem volume estimates, too. Stem volumes extracted from the single scans exhibit a large variability with deviations from the reference volumes ranging from -34% to 44%. By contrast volumes extracted from the merged scans only vary weakly (-2% to 6%) and show a marginal influence of circle fitting. Numéro de notice : A2013-114 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2012.12.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2012.12.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32252
in ISPRS Journal of photogrammetry and remote sensing > vol 77 (March 2013) . - pp 44 - 56[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-2013031 RAB Revue Centre de documentation En réserve L003 Disponible Automated delineation of individual tree crowns from lidar data by multi-scale analysis and segmentation / L. Jing in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 12 (December 2012)
[article]
Titre : Automated delineation of individual tree crowns from lidar data by multi-scale analysis and segmentation Type de document : Article/Communication Auteurs : L. Jing, Auteur ; B. Hu, Auteur ; J. Li, Auteur ; T. Noland, Auteur Année de publication : 2012 Article en page(s) : pp 1275 - 1284 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse multiéchelle
[Termes IGN] arbre (flore)
[Termes IGN] détection automatique
[Termes IGN] détection de contours
[Termes IGN] données lidar
[Termes IGN] segmentation d'imageRésumé : (Auteur) A canopy height model (chm) derived from lidar data can be segmented to obtain individual tree crowns. However, branches, tree crowns, and tree clusters usually have similar shapes and overlapping sizes. This causes current individual tree crown delineation methods for CHMs to work less effectively on closed canopy deciduous or mixed wood forests consisting of various-sized tree crowns. Based on mult-scale analysis and segmentation, an innovative tree crown delineation method was developed in this study. In this method, the scale levels of target tree crowns are first morphologically determined; the CHM is filtered at the multiple scale levels; and local maxima within each filtered CHM are taken as markers to segment the original chm using the marker-controlled watershed method. After tree crown segments are selected from the multiple resulting segmentation maps and integrated together, a complete tree crown map is generated. In an experiment on natural forests in Ontario, Canada, the proposed method yielded crown maps having a good consistency with manual and visual interpretation. For instance, when compared to a manually delineated forest map, the automated method correctly delineated about 69 percent, 65 percent, and 73 percent of the tree crowns from plots of closed canopy coniferous, deciduous, and mixed wood forests, respectively. Numéro de notice : A2012-645 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.78.11.1275 En ligne : https://doi.org/10.14358/PERS.78.11.1275 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32091
in Photogrammetric Engineering & Remote Sensing, PERS > vol 78 n° 12 (December 2012) . - pp 1275 - 1284[article]A wavelet spectral analysis technique for automatic detection of geomagnetic sudden commencements / E. Ghamry in IEEE Transactions on geoscience and remote sensing, vol 50 n° 11 Tome 1 (November 2012)
[article]
Titre : A wavelet spectral analysis technique for automatic detection of geomagnetic sudden commencements Type de document : Article/Communication Auteurs : E. Ghamry, Auteur ; A. Hafez, Auteur ; et al., Auteur Année de publication : 2012 Article en page(s) : pp 4503 - 4512 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géophysique interne
[Termes IGN] analyse spectrale
[Termes IGN] détection automatique
[Termes IGN] tempête magnétique
[Termes IGN] transformation en ondelettesRésumé : (Auteur) Maximal overlap discrete wavelet transform is used to perform spectral analysis of geomagnetic storm sudden commencements (SCs) (SSCs). This spectral analysis guided us in the development of an automatic SSC detection algorithm. The SC can be an indicator of the onset of a geomagnetic storm; in this case, it is called an SSC. The geomagnetic records used in this study were 3-s resolution data collected from the Circum-Pan Pacific Magnetometer Network. Using such high-resolution data enabled us to achieve a small detection error and short processing time. In addition to these technical merits, we introduce a new algorithm that automatically detects, for the first time, the SC from high-resolution data (sampled at the rate of 1 sample/3 s), unlike previous studies that focused on determining the SSC times automatically using 1-min data. Ninety-three geomagnetic storms were considered for testing the proposed algorithm; it was found that the average and maximum standard deviation of the errors in the detection times determined by the algorithm were 7 and 18 samples, respectively, of the corresponding manually determined arrival times. Numéro de notice : A2012-589 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2192279 Date de publication en ligne : 08/05/2012 En ligne : https://doi.org/110.1109/TGRS.2012.2192279 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32035
in IEEE Transactions on geoscience and remote sensing > vol 50 n° 11 Tome 1 (November 2012) . - pp 4503 - 4512[article]Automatic detection and segmentation of orchards using very high resolution imagery / Selim Aksoy in IEEE Transactions on geoscience and remote sensing, vol 50 n° 8 (August 2012)
[article]
Titre : Automatic detection and segmentation of orchards using very high resolution imagery Type de document : Article/Communication Auteurs : Selim Aksoy, Auteur ; I. Yalniz, Auteur ; K. Tasdemir, Auteur Année de publication : 2012 Article en page(s) : pp 3117 - 3131 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse texturale
[Termes IGN] détection automatique
[Termes IGN] image à très haute résolution
[Termes IGN] image Ikonos
[Termes IGN] image optique
[Termes IGN] image Quickbird
[Termes IGN] segmentation d'image
[Termes IGN] Turquie
[Termes IGN] vergerRésumé : (Auteur) Spectral information alone is often not sufficient to distinguish certain terrain classes such as permanent crops like orchards, vineyards, and olive groves from other types of vegetation. However, instances of these classes possess distinctive spatial structures that can be observable in detail in very high spatial resolution images. This paper proposes a novel unsupervised algorithm for the detection and segmentation of orchards. The detection step uses a texture model that is based on the idea that textures are made up of primitives (trees) appearing in a near-regular repetitive arrangement (planting patterns). The algorithm starts with the enhancement of potential tree locations by using multi-granularity isotropic filters. Then, the regularity of the planting patterns is quantified using projection profiles of the filter responses at multiple orientations. The result is a regularity score at each pixel for each granularity and orientation. Finally, the segmentation step iteratively merges neighboring pixels and regions belonging to similar planting patterns according to the similarities of their regularity scores and obtains the boundaries of individual orchards along with estimates of their granularities and orientations. Extensive experiments using Ikonos and QuickBird imagery as well as images taken from Google Earth show that the proposed algorithm provides good localization of the target objects even when no sharp boundaries exist in the image data. Numéro de notice : A2012-385 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2011.2180912 Date de publication en ligne : 31/01/2012 En ligne : https://doi.org/10.1109/TGRS.2011.2180912 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31831
in IEEE Transactions on geoscience and remote sensing > vol 50 n° 8 (August 2012) . - pp 3117 - 3131[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2012081 RAB Revue Centre de documentation En réserve L003 Disponible Extraction of vineyards out of aerial photo-image using texture information / Arnaud Le Bris in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol I-3 (2012)PermalinkBuilding detection in complex scenes thorough effective separation of buildings from trees / M. Awrangjeb in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 7 (July 2012)PermalinkA fuzzy index for detecting spatiotemporal outliers / George Grekousis in Geoinformatica, vol 16 n° 3 (July 2012)PermalinkA framework for automatic and unsupervised detection of multiple changes in multitemporal images / Francesca Bovolo in IEEE Transactions on geoscience and remote sensing, vol 50 n° 6 (June 2012)PermalinkA first set of techniques to detect radio frequency interferences and mitigate their impact on SMOS data / R. Castro in IEEE Transactions on geoscience and remote sensing, vol 50 n° 5 Tome 1 (May 2012)PermalinkAutomated detection of prehistorical rock art features aided by TLS and 2D data co-registration / Jean-Baptiste Lamontre (2012)PermalinkGiving the ‘right’ route directions : the requirements for pedestrian navigation systems / C. Schroder in Transactions in GIS, vol 15 n° 3 (July 2011)PermalinkEdge enhancement algorithm based on the wavelet transform for automatic edge detection InSAR images / Mariví Tello Alonso in IEEE Transactions on geoscience and remote sensing, vol 49 n° 1 Tome 1 (January 2011)PermalinkAutomatic detection and tracking of pedestrians from a moving stereo rig / Konrad Schindler in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 6 (November - December 2010)PermalinkDétection de dommages et évaluation des dégâts du réseau routier après un séisme, en utilisant des images QuickBird haute résolution / A. Haghighattalab in XYZ, n° 124 (septembre - novembre 2010)Permalink