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A combined object- and pixel-based image analysis framework for urban land cover classification of VHR imagery / Bahram Salehi in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 11 (November 2013)
[article]
Titre : A combined object- and pixel-based image analysis framework for urban land cover classification of VHR imagery Type de document : Article/Communication Auteurs : Bahram Salehi, Auteur ; Yun Zhang, Auteur ; Ming Zhong, Auteur Année de publication : 2013 Article en page(s) : pp 999 - 1014 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] carte d'occupation du sol
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] image Ikonos
[Termes IGN] image Quickbird
[Termes IGN] image Worldview
[Termes IGN] Nouveau-Brunswick (Canada)
[Termes IGN] occupation du sol
[Termes IGN] segmentation d'image
[Termes IGN] transformation en ondelettesRésumé : (Auteur) This paper aims at exploiting the advantages of pixel-based and object-based image analysis approaches for urban land cover classification of very high resolution ( VHR ) satellite imagery through a combined object- and pixel-based image analysis framework. The framework starts with segmenting the image resulting in several spectral and spatial features of segments. To overcome the curse of dimensionality, a wavelet- based feature extraction method is proposed to reduce the number of features. The wavelet-based method is automatic, fast, and can preserve local variations in objects' spectral/ spatial signatures. Finally, the extracted features together with the original bands of the image are classified using the conventional pixel-based Maximum Likelihood classification. The proposed method was tested on the WorldView-2, QuickBird, and Ikonos images of the same urban area for comparison purposes. Results show up to 17 percent, 10 percent, and 11 percent improvement in kappa coefficients compared to the case in which only the original bands of the image are used for WV - 2 , QB , and IK , respectively. Furthermore, the objects' spectral features contribute more to increasing classification accuracy than spatial features. Numéro de notice : A2013-596 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.79.11.999 En ligne : https://doi.org/10.14358/PERS.79.11.999 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32732
in Photogrammetric Engineering & Remote Sensing, PERS > vol 79 n° 11 (November 2013) . - pp 999 - 1014[article]Utility of the wavelet transform for LAI estimation using hyperspectral data / Asim Banskota in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 7 (July 2013)
[article]
Titre : Utility of the wavelet transform for LAI estimation using hyperspectral data Type de document : Article/Communication Auteurs : Asim Banskota, Auteur ; Randolph H. Wynne, Auteur ; Shawn P. Serbin, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : 662 p. ; pp 653 - 662 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] algorithme génétique
[Termes IGN] forêt tempérée
[Termes IGN] image AVIRIS
[Termes IGN] image hyperspectrale
[Termes IGN] Leaf Area Index
[Termes IGN] transformation en ondelettes
[Termes IGN] Wisconsin (Etats-Unis)Résumé : (Auteur) We employed the discrete wavelet transform to reflectance spectra obtained from hyperspectral data to improve estimation of LAi in temperate forests. We estimated LAl for 32 plots across a range afforest types in Wisconsin using hemispherical photography. Plot spectra were extracted from AVIRIS data and transformed into wavelet features using the Haar wavelet. Separately, subsets of spectral bands and the Haar features selected by a genetic algorithm were used as independent variables in linear regressions. Models using wavelet coefficients explained the most variance for both broadleaf plots (R2 = 0.90 for wavelet features versus R2 = 0.80 for spectral bands) and all plots independent afforest type (R2 = 0.79 for wavelet features vs. R2 = 0.58 for spectral bands). The forest-type specific models were better than the models using all plots combined. Overall, wavelet features appear superior to band reflectances alone for estimating temperate forest LAI using hyperspectral data. Numéro de notice : A2013-394 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.79.7.653 En ligne : https://doi.org/10.14358/PERS.79.7.653 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32532
in Photogrammetric Engineering & Remote Sensing, PERS > vol 79 n° 7 (July 2013) . - 662 p. ; pp 653 - 662[article]New constraints on the origin of the Hawaiian swell from wavelet analysis of the geoid-to-topography ratio / Cécilia Cadio in Earth and planetary science letters, vol 359–360 (15 December 2012)
[article]
Titre : New constraints on the origin of the Hawaiian swell from wavelet analysis of the geoid-to-topography ratio Type de document : Article/Communication Auteurs : Cécilia Cadio, Auteur ; Maxim D. Ballmer, Auteur ; Isabelle Panet , Auteur ; Michel Diament , Auteur ; Neil Ribe, Auteur Année de publication : 2012 Article en page(s) : pp 40 - 54 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] anomalie de pesanteur
[Termes IGN] convection
[Termes IGN] géoïde local
[Termes IGN] Hawaii (Etats-Unis)
[Termes IGN] houle
[Termes IGN] lithosphère
[Termes IGN] ondelette
[Termes IGN] transformation en ondelettes
[Termes IGN] volcanRésumé : (Auteur) Analyzing the formation mechanism of hotspot swells enhances our understanding of intraplate volcanism and the underlying geodynamical processes. The two main hypotheses for the origin of the archetypal Hawaiian swell are thermal lithospheric thinning, and dynamic support by an ascending plume. Any successful model would have to be able to simultaneously explain the swell topography and the corresponding geoid anomaly. In simple models of isostatic compensation, the geoid-to-topography ratio (GTR) is linearly related to the depth of the compensating mass; therefore it is often considered a fundamental parameter to assess swell support mechanisms. Previous estimates for the geoid-to-topography ratio (GTR) of the Hawaiian swell however are biased towards low values by incomplete removal of the effects of volcanic loading and lithospheric flexure. In order to resolve these issues, we here apply a continuous wavelet transform, which allows resolution of lateral variations of the GTR at various spatial scales. In a series of synthetic tests, the robustness of this approach and its power to identify the origin of hotspot swells are established. With 8 m/km on the youngest part of the chain, the recovered GTR agrees well with the predictions for dynamic support, therefore ruling out thermal rejuvenation as an important mechanism. We also find that the depth of the compensating mass decays by 20 km over a distance of 500 km from Hawaii to Kauai, and identify sublithospheric erosion by small-scale convection in the ponded plume material as a viable mechanism to support this decay. Numéro de notice : A2012-740 Affiliation des auteurs : LAREG+Ext (1991-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.epsl.2012.10.006 Date de publication en ligne : 05/11/2012 En ligne : https://doi.org/10.1016/j.epsl.2012.10.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91475
in Earth and planetary science letters > vol 359–360 (15 December 2012) . - pp 40 - 54[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]Information fusion in the redundant-wavelet-transform domain for noise-robust hyperspectral classification / S. Prasad in IEEE Transactions on geoscience and remote sensing, vol 50 n° 9 (October 2012)
[article]
Titre : Information fusion in the redundant-wavelet-transform domain for noise-robust hyperspectral classification Type de document : Article/Communication Auteurs : S. Prasad, Auteur ; J. Fowler, Auteur ; L. Bruce, Auteur ; W. Li, Auteur Année de publication : 2012 Article en page(s) : pp 3474 - 3486 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] classification dirigée
[Termes IGN] filtrage du bruit
[Termes IGN] fusion de données
[Termes IGN] image hyperspectrale
[Termes IGN] méthode robuste
[Termes IGN] partitionnement
[Termes IGN] redondance de données
[Termes IGN] transformation en ondelettesRésumé : (Auteur) Hyperspectral imagery comprises high-dimensional reflectance vectors representing the spectral response over a wide range of wavelengths per pixel in the image. The resulting high-dimensional feature spaces often result in statistically ill-conditioned class-conditional distributions. Conventional methods for alleviating this problem typically employ dimensionality reduction such as linear discriminant analysis along with single-classifier systems, yet these methods are suboptimal and lack noise robustness. In contrast, a divide-and-conquer approach is proposed to address the high dimensionality of hyperspectral data for effective and noise-robust classification. Central to the proposed framework is a redundant wavelet transform for representing the data in a feature space amenable to noise-robust multiscale analysis as well as a multiclassifier and decision-fusion system for classification and target recognition in high-dimensional spaces under small-sample-size conditions. The proposed partitioning of this feature space assigns a collection of all coefficients across all scales at a particular spectral wavelength to a dedicated classifier. It is demonstrated that such a partitioning of the feature space for a multiclassifier system yields superior noise performance for classification tasks. Additionally, validation studies with experimental hyperspectral data show that the proposed system significantly outperforms conventional denoising and classification approaches. Numéro de notice : A2012-451 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2185053 Date de publication en ligne : 06/03/2012 En ligne : https://doi.org/10.1109/TGRS.2012.2185053 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31897
in IEEE Transactions on geoscience and remote sensing > vol 50 n° 9 (October 2012) . - pp 3474 - 3486[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2012091 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Wavelet‐based directional analysis of the gravity field : evidence for large‐scale undulations / M. Hayn in Geophysical journal international, vol 189 n° 3 (June 2012)PermalinkA nonlocal SAR image denoising algorithm based on LLMMSE wavelet shrinkage / S. Parrilli in IEEE Transactions on geoscience and remote sensing, vol 50 n° 2 (February 2012)PermalinkEffect of climatic cycles in Pacific Ocean on mean sea level variations over the Southwest Pacific Ocean and Tasman Sea / Anthony Wiart (2012)PermalinkFlexible dataset combination and modelling by domain decomposition approaches / Isabelle Panet (2012)PermalinkInterference suppression algorithm for SAR based on time-frequency transform / S. Zhang in IEEE Transactions on geoscience and remote sensing, vol 49 n° 10 Tome 1 (October 2011)PermalinkOndelettes et théorie des évidences pour la classification orientée-objet : Caractérisation et suivi des changements d’occupation des sols de la métropole de Rennes / A. Lefebvre in Revue internationale de géomatique, vol 21 n° 3 (septembre - novembre 2011)PermalinkTLS data denoising by range image processing / Eddy Smigiel in Photogrammetric record, vol 26 n° 134 (June - August 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)PermalinkWavelet modelling of the gravity field by domain decomposition methods: an example over Japan / Isabelle Panet in Geophysical journal international, vol 184 n° 1 (January 2011)PermalinkWavelets and notch filtering: innovative techniques for mitigating RF interference / M. Paonni in Inside GNSS, vol 6 n° 1 (January - February 2011)PermalinkMathématiques pour le traitement du signal / M. Bergounioux (2010)PermalinkUtilisation conjointe d'mageries optique et radar haute résolution spatiale pour la cartographie de l'occupation du sol dans un contexte tropical / Mohamed Sebane (2010)PermalinkClassical globally reflected gravity field determination in modern locally oriented multiscale framework / W. Freeden in Journal of geodesy, vol 83 n° 12 (December 2009)PermalinkWavelet modeling of the gravity field over Japan / Isabelle Panet in Bulletin of the Geographical survey institute, vol 57 (December 2009)PermalinkAdvanced full-waveform lidar data echo detection: assessing quality of derived terrain and tree height models in an alpine coniferous forest / Adrien Chauve in International Journal of Remote Sensing IJRS, vol 30 n° 19 (October 2009)PermalinkA Wavelet and IHS integration method to fuse high resolution SAR with moderate resolution multispectral images / G. Hong in Photogrammetric Engineering & Remote Sensing, PERS, vol 75 n° 10 (October 2009)PermalinkMerging hyperspectral and panchromatic image data: qualitative and quantitative analysis / M. Cetin in International Journal of Remote Sensing IJRS, vol 30 n° 7 (April 2009)PermalinkA wavelet based technique for sea wind extraction from SAR images / S. Zecchetto in IEEE Transactions on geoscience and remote sensing, vol 46 n° 10 Tome 1 (October 2008)PermalinkOptimizing the high-pass filter addition technique for image fusion / U.G. Gangkofner in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 9 (September 2008)PermalinkComparison of nine fusion techniques for very high resolution data / K.G. Nikolapoulos in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 5 (May 2008)Permalink