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Sea ice deformation state from Synthetic Aperture Radar Imagery: part 2 Effects of spatial resolution and noise level / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 46 n° 8 (August 2008)
[article]
Titre : Sea ice deformation state from Synthetic Aperture Radar Imagery: part 2 Effects of spatial resolution and noise level Type de document : Article/Communication Auteurs : W. Dierking, Auteur ; J. Dall, Auteur Année de publication : 2008 Article en page(s) : pp 2197 - 2207 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] filtrage du bruit
[Termes IGN] glace de mer
[Termes IGN] image aérienne
[Termes IGN] image ALOS-PALSAR
[Termes IGN] image Envisat-ASAR
[Termes IGN] image ERS-SAR
[Termes IGN] image radar
[Termes IGN] pouvoir de résolution géométrique
[Termes IGN] radargrammétrie
[Termes IGN] rapport signal sur bruitRésumé : (Auteur) C- and L-band airborne synthetic aperture radar (SAR) imagery acquired at like- and cross-polarizations over sea ice under winter conditions is examined with the objective to study the discrimination between level ice and ice deformation features. High-resolution low-noise data were analyzed in the first paper. In this second paper, the main topics are the effects of spatial resolution and signal-to-noise ratio. Airborne high-resolution SAR scenes are used to generate a sequence of images with increasingly coarser spatial resolution from 5 to 25 m, keeping the number of looks constant. The signal-to-noise ratio is varied between typical noise levels for airborne imagery and satellite data. Areal fraction of deformed ice and average deformation distance are determined for each image product. At L-band, the retrieved values of the areal fraction get larger as the image resolution is degraded. The areal fraction at C-band remains constant. The retrieved average distance between deformation features increases both at C- and L-bands as the image resolution gets coarser. The influence of noise becomes noticeable if its level is equal or larger than the average intensity backscattered from the level ice. The retrieval of deformation parameters using simulated images that resemble ERS-2 SAR, Envisat ASAR, and ALOS PALSAR data products is discussed. Basic differences between real and simulated ERS-2 SAR images are analyzed. Copyright IEEE Numéro de notice : A2008-398 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2008.917267 En ligne : https://doi.org/10.1109/TGRS.2008.917267 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29487
in IEEE Transactions on geoscience and remote sensing > vol 46 n° 8 (August 2008) . - pp 2197 - 2207[article]Voir aussiRéservation
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Code-barres Cote Support Localisation Section Disponibilité 065-08081 RAB Revue Centre de documentation En réserve L003 Disponible Assimilation of remote sensed data for improved latent and sensible heat flux prediction: a comparative synthetic study / R. Pipunic in Remote sensing of environment, vol 112 n° 4 (15/04/2008)
[article]
Titre : Assimilation of remote sensed data for improved latent and sensible heat flux prediction: a comparative synthetic study Type de document : Article/Communication Auteurs : R. Pipunic, Auteur ; J. Walker, Auteur ; A. Western, Auteur Année de publication : 2008 Article en page(s) : pp 1295 - 1305 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse comparative
[Termes IGN] chaleur
[Termes IGN] filtre de Kalman
[Termes IGN] flux de rayonnement
[Termes IGN] humidité du sol
[Termes IGN] image Terra-MODIS
[Termes IGN] modèle numérique de surface
[Termes IGN] SMOSRésumé : (Auteur) Predicted latent and sensible heat fluxes from Land Surface Models (LSMs) are important lower boundary conditions for numerical weather prediction. While assimilation of remotely sensed surface soil moisture is a proven approach for improving root zone soil moisture, and presumably latent (LE) and sensible (H) heat flux predictions from LSMs, limitations in model physics and over-parameterisation mean that physically realistic soil moisture in LSMs will not necessarily achieve optimal heat flux predictions. Moreover, the potential for improved LE and H predictions from the assimilation of LE and H observations has received little attention by the scientific community, and is tested here with synthetic twin experiments. A one-dimensional single column LSM was used in 3-month long experiments, with observations of LE, H, surface soil moisture and skin temperature (from which LE and H are typically derived) sampled from truth model run outputs generated with realistic data inputs. Typical measurement errors were prescribed and observation data sets separately assimilated into a degraded model run using an Ensemble Kalman Filter (EnKF) algorithm, over temporal scales representative of available remotely sensed data. Root Mean Squared Error (RMSE) between assimilation and truth model outputs across the experiment period were examined to evaluate LE, H, and root zone soil moisture and temperature retrieval. Compared to surface soil moisture assimilation as will be available from SMOS (every 3 days), assimilation of LE and/or H using a best case MODIS scenario (twice daily) achieved overall better predictions for LE and comparable H predictions, while achieving poorer soil moisture predictions. Twice daily skin temperature assimilation achieved comparable heat flux predictions to LE and/or H assimilation. Fortnightly (Landsat) assimilations of LE, H and skin temperature performed worse than 3-day moisture assimilation. While the different spatial resolutions of these remote sensing data have been ignored, the potential for LE and H assimilation to improve model predicted LE and H is clearly demonstrated. Copyright Elsevier Numéro de notice : A2008-089 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2007.02.038 En ligne : https://doi.org/10.1016/j.rse.2007.02.038 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29084
in Remote sensing of environment > vol 112 n° 4 (15/04/2008) . - pp 1295 - 1305[article]Retrieving soil temperature profile by assimilating MODIS LST products with ensemble Kalman filter / C. Huang in Remote sensing of environment, vol 112 n° 4 (15/04/2008)
[article]
Titre : Retrieving soil temperature profile by assimilating MODIS LST products with ensemble Kalman filter Type de document : Article/Communication Auteurs : C. Huang, Auteur ; X. Li, Auteur ; L. Lu, Auteur Année de publication : 2008 Article en page(s) : pp 1320 - 1336 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] chaleur terrestre
[Termes IGN] filtre de Kalman
[Termes IGN] image Aqua-MODIS
[Termes IGN] mise à jour automatique
[Termes IGN] Mongolie
[Termes IGN] prédiction
[Termes IGN] température au solRésumé : (Auteur) Proper estimation of initial state variables and model parameters are vital importance for determining the accuracy of numerical model prediction. In this work, we develop a one-dimensional land data assimilation scheme based on ensemble Kalman filter and Common Land Model version 3.0 (CoLM). This scheme is used to improve the estimation of soil temperature profile. The leaf area index (LAI) is also updated dynamically by MODIS LAI production and the MODIS land surface temperature (LST) products are assimilated into CoLM. The scheme was tested and validated by observations from four automatic weather stations (BTS, DRS, MGS, and DGS) in Mongolian Reference Site of CEOP during the period of October 1, 2002 to September 30, 2003. Results indicate that data assimilation improves the estimation of soil temperature profile about 1 K. In comparison with simulation, the assimilation results of soil heat fluxes also have much improvement about 13 W m- 2 at BTS and DGS and 2 W m- 2 at DRS and MGS, respectively. In addition, assimilation of MODIS land products into land surface model is a practical and effective way to improve the estimation of land surface variables and fluxes. Copyright Elsevier Numéro de notice : A2008-091 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2007.03.028 En ligne : https://doi.org/10.1016/j.rse.2007.03.028 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29086
in Remote sensing of environment > vol 112 n° 4 (15/04/2008) . - pp 1320 - 1336[article]Use of a Kalman filter for the retrieval of surface BRDF coefficients with a time-evolving model based on the ECOCLIMAP land cover classification / O. Samain in Remote sensing of environment, vol 112 n° 4 (15/04/2008)
[article]
Titre : Use of a Kalman filter for the retrieval of surface BRDF coefficients with a time-evolving model based on the ECOCLIMAP land cover classification Type de document : Article/Communication Auteurs : O. Samain, Auteur ; J.L. Roujeau, Auteur ; Bernhard Geiger, Auteur Année de publication : 2008 Article en page(s) : pp 1337 - 1346 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Afrique occidentale
[Termes IGN] cohérence des données
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] filtre de Kalman
[Termes IGN] image SPOT-Végétation
[Termes IGN] image Terra-MODIS
[Termes IGN] occupation du sol
[Termes IGN] réflectance de surface
[Termes IGN] réflectance directionnelle
[Termes IGN] variation saisonnièreRésumé : (Auteur) The goal of this study is to demonstrate the asset in using a Kalman filter to improve the spatial coherence and time consistency of surface Bidirectional Reflectance Distribution Function (BRDF) and albedo retrievals from moderate resolution sensor data sets. For this purpose, we use a simple surface model describing BRDF seasonal evolution for the land cover classes of the ECOCLIMAP database. The application of temporal composition windows used so far for BRDF retrieval is limited in regions characterized by a high frequency of cloud coverage, which induces a lot of gaps in the temporal series. Instead, the present method ensures a continuous production of surface BRDF parameters thanks to the Kalman filter recursive data processing. An application of the method is performed with SPOT/VEGETATION data over the western Africa equatorial region for the year 2003. Compared to presently available products from VEGETATION and MODIS instruments, this new approach allows to fill the gaps and improves the retrieved parameters time consistency. Another interesting possibility of the Kalman filter is the production of surface biophysical variables in quasi-real-time for applications that require a frequent update of the surface parameters. Copyright Elsevier Numéro de notice : A2008-092 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2007.07.007 En ligne : https://doi.org/10.1016/j.rse.2007.07.007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29087
in Remote sensing of environment > vol 112 n° 4 (15/04/2008) . - pp 1337 - 1346[article]Applications of ICA for the enhancement and classification of polarimetric SAR images / H. Wang in International Journal of Remote Sensing IJRS, vol 29 n° 6 (March 2008)
[article]
Titre : Applications of ICA for the enhancement and classification of polarimetric SAR images Type de document : Article/Communication Auteurs : H. Wang, Auteur ; Y. Pi, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 1649 - 1663 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] analyse en composantes indépendantes
[Termes IGN] couleur à l'écran
[Termes IGN] données polarimétriques
[Termes IGN] filtre de déchatoiement
[Termes IGN] image en couleur composée
[Termes IGN] image radar moirée
[Termes IGN] image RVBRésumé : (Auteur) Independent components analysis (ICA) based methods for polarimetric synthetic aperture radar (SAR) image speckle reduction and ground object classification are studied. Several independent components can be extracted from polarimetric SAR images using ICA directly. The component with lowest speckle index is regarded as the scene after speckle reduction. The disadvantage of this method is that only one image is kept and most polarization information will be lost. In this paper, we use ICA-sparse-coding shrinkage (ICA-SPS) based speckle reduction method, which is implemented on each individual image and can keep polarization information. It is carried out on the combined channels obtained by Pauli-decomposition rather than original polarization channels in order to keep relative phase information among polarization channels and get better performance. After ICA-SPS, the effect of speckle suppression on SAR image classification can be compared favourably with other methods by combining the channels into a false colour image. At last, a new ICA-based classification method is presented. In this method, four independent components are separated by ICA from five polarization and combined channels. One of these independent components which includes little ground object information is regarded as speckle noise and therefore be discarded. The remaining three components can be treated as subordination coefficients of three kinds of targets. A classified image can be obtained based on the components. And by composing these three channels in RGB colour pattern, a false colour image can be constructed. Numéro de notice : A2008-085 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701395211 En ligne : https://doi.org/10.1080/01431160701395211 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29080
in International Journal of Remote Sensing IJRS > vol 29 n° 6 (March 2008) . - pp 1649 - 1663[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-08041 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Texture feature fusion with neighborhood oscillating tabu search for high resolution image classification / L. Zhang in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 3 (March 2008)PermalinkPermalinkEtude sur la restitution fine de l'axe de visée d'un instrument optronique embarqué / Adeline Coupé (2008)PermalinkGPS composite clock analysis / James R. Wright in International Journal of Navigation and Observation, vol 2008 (01/01/2008)PermalinkImagerie spatiale / P. Lier (2008)PermalinkKalman filtering, theory and practice using MATLAB / Mohinder S. Grewal (2008)PermalinkPrinciples of GNSS, inertial, and multisensor integrated navigation systems / Paul D. Groves (2008)PermalinkDespeckle and geographical feature extraction in SAR images by wavelet transform / Karunesh K. Gupta in ISPRS Journal of photogrammetry and remote sensing, vol 62 n° 6 (November-December 2007)PermalinkComputation of random errors in digital terrain models / J. Bjorke in Geoinformatica, vol 11 n° 3 (September - November 2007)PermalinkNetwork RTK: getting ready for GNSS modernization / H. Landau in GPS world, vol 18 n° 4 (April 2007)Permalink