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Assessing the feasibility of a global model for multi-temporal burned area mapping using Spot-Vegetation data / J.M. Silva in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 25 n° 22 (November 2004) . - pp 4889 - 4913 Titre : Assessing the feasibility of a global model for multi-temporal burned area mapping using Spot-Vegetation data Type de document : Article/Communication Auteurs : J.M. Silva, Auteur ; J.F. Cadima, Auteur ; J.M. Pereira, Auteur ; J.M. Gregoire, Auteur Année de publication : 2004 Article en page(s) : pp 4889 - 4913 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] bande infrarouge [Termes IGN] cartographie thématique [Termes IGN] étude de faisabilité [Termes IGN] forêt tropicale [Termes IGN] image SPOT-Végétation [Termes IGN] incendie [Termes IGN] Normalized Difference Vegetation Index [Termes IGN] zone boréale [Termes IGN] zone intertropicale [Termes IGN] zone tempérée Résumé : (Auteur) The possibility of using the Système Probatoire de l'Observation de la Terre (SPOT)-VEGETATION (VGT) data for global burned area mapping with a single algorithm was investigated. Using VGT images from south-eastern Africa, the Iberian Peninsula and south-eastern Siberia/north-eastern China, we analysed the variability of the spectral signature of burned areas and its relationship with land cover, and performed the selection of the best variables for burned area mapping. The results show that in grasslands and croplands, near-infrared (NIR) and short-wave infrared (SWIR) reflectance always decreases as a result of fire. In forests and woodlands, there may occur a simultaneous decrease of SWIR and NIR or an increase of SWIR and a decrease of NIR. Burning of green vegetation (high values of the Normalized Difference Vegetation Index (NDVI)) tends to result in an increase of the SWIR. The best variables for burned area mapping are different in each region. Only the NIR allows a good discrimination of burned areas in all study areas. We derived a logistic regression model for multi-temporal burned area mapping in tropical, temperate and boreal regions, which handles the spectral variability of burned areas dependent on the type of vegetation. The results underline the feasibility of a single model for global burned area mapping. Numéro de notice : A2004-486 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27004 [article]

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Comparison of different speckle-reduction techniques in SAR images using wavelet transform / A. Vidal-Pantaleoni in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 25 n° 22 (November 2004) . - pp 4915 - 4932 Titre : Comparison of different speckle-reduction techniques in SAR images using wavelet transform Type de document : Article/Communication Auteurs : A. Vidal-Pantaleoni, Auteur ; D. Marti, Auteur Année de publication : 2004 Article en page(s) : pp 4915 - 4932 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] analyse comparative [Termes IGN] filtrage du bruit [Termes IGN] filtre de déchatoiement [Termes IGN] filtre de Wiener [Termes IGN] image ERS-SAR [Termes IGN] seuillage d'image [Termes IGN] transformation en ondelettes Résumé : (Auteur) Speckle noise is always present in Synthetic Aperture Radar (SAR) images. Many methods that reduce speckle noise while preserving texture and detail have been presented previously. In this paper, a comparison of different methods using wavelet decomposition is performed and new improvements for traditional methods are introduced. These techniques are: Wiener filtering, classical soft threshold, a new adaptive soft threshold and Bayesian reconstruction. First, speckle noise in a SAR image was analysed statistically. Then, a simulated image following these characteristics was created in order to evaluate noise reduction. The mean squared error was classified depending on the spatial characteristics of a local region. This tool gave valuable information for algorithm assessment. In the comparison, the new adaptive soft threshold method provided excellent results concerning noise reduction and detail preservation compared with classical soft threshold and Wiener methods. In addition, it gave as much noise reduction as the most sophisticated Bayesian method, but much more efficiently. Hence, the adaptive version of soft thresholding outperformed the other techniques. This study also presents a rigorous framework for speckle noise simulation and noise reduction evaluation. Numéro de notice : A2004-487 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27005 [article]

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Discrimination potential of X-band polarimetric SAR data / Nicolas Baghdadi in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 25 n° 22 (November 2004) . - pp 4933 - 4943 Titre : Discrimination potential of X-band polarimetric SAR data Type de document : Article/Communication Auteurs : Nicolas Baghdadi, Auteur ; N. Holah, Auteur ; P. Dubois-Fernandez, Auteur ; L. Prevot, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 4933 - 4943 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications [Termes IGN] analyse discriminante [Termes IGN] anisotropie [Termes IGN] Avignon [Termes IGN] bande X [Termes IGN] données polarimétriques [Termes IGN] image radar moirée [Termes IGN] image RAMSES [Termes IGN] Radar Aéroporté Multi-Spectral d'Etude des Signatures [Termes IGN] sol nu Résumé : (Auteur) In anticipation of X-band polarimetric Synthetic Aperture Radar (SAR) data from future sensors, we investigated the potential of X-band fully polarimetric data for discriminating between the principal classes present in a study site near Avignon, France. Decomposition and analysis techniques have been applied to a dataset acquired by the ONERA airborne RAMSES (Radar Aéroporté Multi-Spectral d'Etude des Signatures) SAR. Results show that X-band provides some discrimination capability. The polarimetric parameters, entropy and Ü-angle, show clearly that these signature classes are grouped into five clusters corresponding to physical scattering characteristics. The introduction of the anisotropy parameter does not increase our ability to distinguish between different classes whose clusters are in the same entropy/Ü-angle zone. The correlation observed between the radar signal and the surface roughness over bare soils is very low. Numéro de notice : A2004-488 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27006 [article]

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An automatic nonlinear correlation approach for processing of hyperspectral images / R.N. Ingram in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 25 n° 22 (November 2004) . - pp 4981 - 4998 Titre : An automatic nonlinear correlation approach for processing of hyperspectral images Type de document : Article/Communication Auteurs : R.N. Ingram, Auteur ; A.S. Lewis, Auteur ; R.L. Tutwiler, Auteur Année de publication : 2004 Article en page(s) : pp 4981 - 4998 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] corrélation automatique de points homologues [Termes IGN] équation non linéaire [Termes IGN] image AVIRIS [Termes IGN] image hyperspectrale [Termes IGN] méthode robuste [Termes IGN] traitement parallèle Résumé : (Auteur) Hyperspectral imaging technology demands sophisticated processing techniques that offer precise characterizations of complex spectral signatures. A nonlinear correlator structure is implemented for interference mitigation and object recognition. A key asset is the correlator's applicability to both the spatial (two-dimensional) and spectral (one-dimensional) domains, thus ideal for hyperspectral processing. The process consists of a standard convolution summed with a nonlinear adaptive term. The premise is the same in each case but the mathematical implementation is different. By performing the correlation calculations in the frequency domain, the processing algorithm is efficient, robust, and well suited for implementation on a parallel processing computational architecture. The nonlinear correlator depends on two parameters and an algorithm to determine these parameters based only on the input image (two-dimensional) or spectral signature (one-dimensional) is presented. Based on the results with the selected spatial and spectral templates, a target is identified and the spatial coordinates as well as the spectral signature are input to the final fusion stage, which analyses both spectral and spatial signatures for a correct target identification. Several examples are given and insights to template (mask) selection are provided. Numéro de notice : A2004-489 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27007 [article]

Exemplaires (1)

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True orthoimage generation in urban areas with very tall buildings / G. Zhou in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 25 n° 22 (November 2004) . - pp 5163 - 5180 Titre : True orthoimage generation in urban areas with very tall buildings Type de document : Article/Communication Auteurs : G. Zhou, Auteur ; W. Schickler, Auteur ; A. Thorpe, Auteur Année de publication : 2004 Article en page(s) : pp 5163 - 5180 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Orthophotographie, orthoimage [Termes IGN] bâtiment [Termes IGN] Denver [Termes IGN] milieu urbain [Termes IGN] modèle 3D de l'espace urbain [Termes IGN] modèle numérique de surface [Termes IGN] modèle numérique de sursol [Termes IGN] modèle numérique de terrain [Termes IGN] New York (Etats-Unis ; ville) [Termes IGN] orthoimage intégrale Résumé : (Auteur) The orthoirnage usually serves as a valuable base layer in GIS. With an increasing demand in many urban GIS applications, orthoimages in urban areas are required to represent spatial objects in their true positions. However, the traditional methods for orthoimage generation did not consider features (e.g. occlusion, shadow. etc.) of spatial objects (e.g. bridges and buildings), resulting in that spatial objects in the created orthoimages cannot be located in their true positions. This paper presents our research and experimental results of true orthoimage generation in extremely tall urban areas using lidar and multi-view large-scale aerial images. Lidar data are used for the extraction of an urban digital surface model (DSM), further for the extraction of a digital building model (DBM) and a digital terrain model (DTM). Data structure and a data model for managing urban spatial objects, such as buildings and bridges, are developed. The photogrammetric geometry is used for the detection of occluded and shadowed areas in true orthoimage generation. For the occluded and shadowed areas, lost information is compensated from a conjugate area in adjacent images, for which a new mosaicking method, which automatically chooses the 'best' imagery and automatically optimizes the seam line, has been developed. Experimental results from central Denver, Colorado and Lower Manhattan, New York City demonstrated that the proposed true orthoimage generation scheme in this paper is capable of truly orthorectifying the relief displacement in aerial images and significantly reducing occlusion and shadow defects. Numéro de notice : A2004-491 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27008 [article]

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DSM generation and evaluation from QuickBird stereo imagery with 3D physical modelling / Thierry Toutin in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)

Public [article]  inInternational Journal of Remote Sensing IJRS > vol 25 n° 22 (November 2004) . - pp 5181 - 5193 Titre : DSM generation and evaluation from QuickBird stereo imagery with 3D physical modelling Type de document : Article/Communication Auteurs : Thierry Toutin, Auteur Année de publication : 2004 Article en page(s) : pp 5181 - 5193 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique [Termes IGN] compensation par faisceaux [Termes IGN] couvert végétal [Termes IGN] données altimétriques [Termes IGN] données lidar [Termes IGN] image Quickbird [Termes IGN] modèle numérique de surface [Termes IGN] modèle numérique de terrain [Termes IGN] modèle stéréoscopique [Termes IGN] occupation du sol [Termes IGN] Québec (Québec ; ville) [Termes IGN] stéréoscopie Résumé : (Auteur) A digital terrain model (DTM) extracted from QuickBird in-track stereo images using a three-dimensional (3D) multisensor physical model developed at the Canada Centre for Remote Sensing, Natural Resources Canada was evaluated. Firstly. the stereo photogrammetric bundle adjustment was set-up with about 10 accurate ground control points and 1-2 m errors in the three axes were obtained over 48 independent checkpoints. The DTM was then generated using an area-based multi-scale image matching method and 3D semi-automatic editing tools and then compared to lidar elevation data with 0.2-m accuracy. An elevation error with 68% confidence level (LE68) of 6.4m was achieved over the full area. Since the DTM is in fact a digital surface model where the height, or a part, of land cover (trees, houses) is included, the accuracy depends on the land cover types. Using 3D visual classification of the stereo QuickBird images, different classes (deciduous, conifer, mixed and sparse forests, residential areas, bare soils and lakes) were generated to take into account the height of the surfaces (natural and human-made) in the accuracy evaluation. LE68 values of 3.4 m to 6.7 m were thus obtained depending on the land cover types with biases representative of the surface heights. On the other hand, LE68 values of 0.5m and 1.3 m with no bias were obtained for lakes and bare soils respectively. These last results are more representative of the real stereo QuickBird potential for DTM and 5-m contour line generation, compliant with the highest topographic standard. Since the images were acquired in wintertime and the lidar data in summertime, better results could thus be expected when using stereo images acquired in summertime, mainly in deciduous forests to integrate the full canopy height into the DSM. Numéro de notice : A2004-492 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27009 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
080-04201	RAB	Revue	Centre de documentation	En réserve 3L	Exclu du prêt