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Seeing the trees in the forest: Using Lidar and multispectral data fusion with local filtering and variable window size for estimating tree height / S.C. Pospecu in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 5 (May 2004)
[article]
Titre : Seeing the trees in the forest: Using Lidar and multispectral data fusion with local filtering and variable window size for estimating tree height Type de document : Article/Communication Auteurs : S.C. Pospecu, Auteur ; R. Wynne, Auteur Année de publication : 2004 Article en page(s) : pp 589 - 604 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] couvert forestier
[Termes IGN] données lidar
[Termes IGN] estimation statistique
[Termes IGN] feuillu
[Termes IGN] fusion d'images
[Termes IGN] hauteur des arbres
[Termes IGN] identification automatique
[Termes IGN] image multibande
[Termes IGN] modèle de régression
[Termes IGN] Pinus (genre)Résumé : (Auteur) The main study objective was to develop robust processing and analysis techniques to facilitate the use of small-footprint lidar data for estimating plot-level tree height by measuring individual trees identifiable on the three-dimensional lidar surface. Lidar processing techniques included data fusion with multispectral optical data and local filtering with both square and circular windows of variable size. The lidar system used for this study produced an average footprint of 0.65 m and an average distance between laser shots of 0.7 m. The lidar data set was acquired over deciduous and coniferous stands with settings typical of the southeastern United States. The lidar-derived tree measurements were used with regression models and cross-validation to estimate tree height on 0.017-ha plots. For the pine plots, lidar measurements explained 97 percent of the variance associated with the mean height of dominant trees. For deciduous plots, regression models explained 79 percent of the mean height variance for dominant trees. Filtering for local maximum with circular windows gave better fitting models for pines, while for deciduous trees, filtering with square windows provided a slightly better model fit. Using lidar and optical data fusion to differentiate between forest types provided better results for estimating average plot height for pines. Estimating tree height for deciduous plots gave superior results without calibrating the search window size based on forest type. Numéro de notice : A2004-181 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.70.5.589 En ligne : https://doi.org/10.14358/PERS.70.5.589 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26708
in Photogrammetric Engineering & Remote Sensing, PERS > vol 70 n° 5 (May 2004) . - pp 589 - 604[article]Refinement of wavelength calibrations of hyperspectral imaging data using a spectrum-machine technique / B.C. Gao in Remote sensing of environment, vol 90 n° 4 (30/04/2004)
[article]
Titre : Refinement of wavelength calibrations of hyperspectral imaging data using a spectrum-machine technique Type de document : Article/Communication Auteurs : B.C. Gao, Auteur ; M.J. Montes, Auteur ; C.O. Davis, Auteur Année de publication : 2004 Article en page(s) : pp 424 - 433 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] capteur multibande
[Termes IGN] étalonnage radiométrique
[Termes IGN] étalonnage spectral
[Termes IGN] image hyperspectrale
[Termes IGN] longueur d'onde
[Termes IGN] spectre électromagnétique
[Termes IGN] spectromètre imageurRésumé : (Auteur) The concept of imaging spectrometry, or hyperspectral imaging, is becoming increasingly popular in scientific communities in recent years. Hyperspectral imaging data covering the spectral region between 0.4 and 2.5 um and collected from aircraft and satellite platforms have been used in the study of the earth's atmosphere, land surface, and ocean color properties, as well as on planetary missions. In order to make such quantitative studies, accurate radiometric and spectral calibrations of hyperspectral imaging data are necessary. Calibration coefficients for all detectors in an imaging spectrometer obtained in a laboratory may need to be adjusted when applied to data obtained from an aircraft or a satellite platform. Shifts in channel center wavelengths and changes in spectral resolution may occur when an instrument is airborne or spaceborne due to vibrations, and to changes in instrument temperature and pressure. In this paper, we describe an algorithm for refining spectral calibrations of imaging spectrometer data using observed features in the data itself. The algorithm is based on spectrum-matching of atmospheric water vapor, oxygen, and carbon dioxide bands, and solar Fraunhofer lines. It has been applied to real data sets acquired with airborne and spaceborne imaging spectrometers. Numéro de notice : A2004-189 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.09.002 En ligne : https://doi.org/10.1016/j.rse.2003.09.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26716
in Remote sensing of environment > vol 90 n° 4 (30/04/2004) . - pp 424 - 433[article]A comparative assessment on the use of SAR and high-resolution optical images in ocean dynamics studies / D.A. Gagliardini in International Journal of Remote Sensing IJRS, vol 25 n° 7 (April 2004)
[article]
Titre : A comparative assessment on the use of SAR and high-resolution optical images in ocean dynamics studies Type de document : Article/Communication Auteurs : D.A. Gagliardini, Auteur ; A.C. Colon, Auteur Année de publication : 2004 Article en page(s) : pp 1271 - 1275 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] image à haute résolution
[Termes IGN] image multitemporelle
[Termes IGN] image optique
[Termes IGN] radar à antenne synthétiqueRésumé : (Auteur) A comparison of Synthetic Aperture Radar (SAR) images acquired by the ERS-2 and RADARSAT-1 satellites with Landsat Thematic Mapper (TM) images acquired close in time is presented. Similarities and differences on the kind of ocean information they provide are discussed. The images were acquired over the Brazil-Malvinas (Falkland) Confluence under different solar elevation and azimuth angles. Ocean features observed by both types of sensors are discussed. These observations show that (1) at high solar angles, sun glint prevails over upwelled water-leaving radiance resulting in optical images that tend to provide dynamical information similar to that obtained from SAR imagery and (2) at low solar zenith and azimuth angles, upwelled radiation tends to prevail over sun glint, providing typical ocean colour and water quality information that can still complement and aid in the interpretation of SAR observations. Numéro de notice : A2004-090 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160310001592166 En ligne : https://doi.org/10.1080/01431160310001592166 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26617
in International Journal of Remote Sensing IJRS > vol 25 n° 7 (April 2004) . - pp 1271 - 1275[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-04071 RAB Revue Centre de documentation En réserve L003 Exclu du prêt SeaWIFS validation in European coastal waters using optical and bio-geochemical measurements / S.J. Lavender in International Journal of Remote Sensing IJRS, vol 25 n° 7 (April 2004)
[article]
Titre : SeaWIFS validation in European coastal waters using optical and bio-geochemical measurements Type de document : Article/Communication Auteurs : S.J. Lavender, Auteur ; M.H. Pinkerton, Auteur ; J.M. Froidefond, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 1481 - 1488 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bande visible
[Termes IGN] biologie
[Termes IGN] chlorophylle
[Termes IGN] eaux côtières
[Termes IGN] géochimie
[Termes IGN] image optique
[Termes IGN] image Seawifs
[Termes IGN] océanographie spatialeRésumé : (Auteur) The National Aeronautics & Space Administration (NASA) Sea viewing Wide Field of view Sensor (SeaWiFS) began operational measurement of ocean colour in September 1997. Upgrades to the SeaWiFS data processing system (SeaDAS) have occurred frequently and the effects of these revisions on the remotely sensed estimates of chlorophyll-a concentration (chl-a) have been significant. Measurements of chl-a from research work in the Bay of Biscay and Gulf of Cadiz during 1998-1999 are used to validate the SeaWiFS chl-a product generated using the current version of SeaDAS (version 4.1). The validation data cover coastal and offshore waters, including those dominated by inorganic suspended sediment, and an intense dinoflagellate bloom where shipboard chl-a measurements exceeded 50mgm-3. The standard SeaWiFS chlorophyll algorithm (OC4v4) generally performed well, but significantly over-estimated chl-a where inorganic suspended sediment was present. The algorithm is only applicable to chl-a values up to 64mgm-3, which was less than chl-a at the centre of the bloom. A novel algorithm for chl-a, which first estimates the inherent optical properties of the water, was applied to the SeaWiFS measurements but failed on over 90% of the pixels, perhaps because SeaWiFS is under-estimating water reflectance at the extreme blue end of the visible spectrum. Numéro de notice : A2004-095 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160310001592481 En ligne : https://doi.org/10.1080/01431160310001592481 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26622
in International Journal of Remote Sensing IJRS > vol 25 n° 7 (April 2004) . - pp 1481 - 1488[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-04071 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Classification of remotely sensed imagery stochastic gradient boosting as a refinement of classification tree analysis / R. Lawrence in Remote sensing of environment, vol 90 n° 3 (15/04/2004)
[article]
Titre : Classification of remotely sensed imagery stochastic gradient boosting as a refinement of classification tree analysis Type de document : Article/Communication Auteurs : R. Lawrence, Auteur ; A. Bunn, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 331 - 336 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] classification
[Termes IGN] décomposition d'image
[Termes IGN] image hyperspectrale
[Termes IGN] image Ikonos
[Termes IGN] image Landsat-ETM+
[Termes IGN] image PROBE
[Termes IGN] précision de la classification
[Termes IGN] sylvicultureRésumé : (Auteur) Classification tree analysis (CTA) provides an effective suite of algorithms for classifying remotely sensed data, but it has the limitations of (1) not searching for optimal tree structures and (2) being adversely affected by outliers, inaccurate training data, and unbalanced data sets. Stochastic gradient boosting (SGB) is a refinement of standard CTA that attempts to minimize these limitations by (1) using classification errors to iteratively refine the trees using a random sample of the training data and (2) combining the multiple trees iteratively developed to classify the data. We compared traditional CTA results to SGB for three remote sensing based data sets, an IKONOS image from the Sierra Nevada Mountains of California, a Probe-1 hyperspectral image from the Virginia City mining district of Montana, and a series of Landsat ETM+ images from the Greater Yellowstone Ecosystem (GYE). SGB improved the overall accuracy of the IKONOS classification from 84% to 95% and the Probe-1 classification from 83% to 93%. The worst performing classes using CTA exhibited the largest increases in class accuracy using SGB. A slight decrease in overall classification accuracy resulted from the SGB analysis of the Landsat data. Numéro de notice : A2004-200 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.01.007 En ligne : https://doi.org/10.1016/j.rse.2004.01.007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26727
in Remote sensing of environment > vol 90 n° 3 (15/04/2004) . - pp 331 - 336[article]Hyperspectral vegetation indices and novel algorithms for predicting green LAI of crop canopies: modelling and validation in the context of precision agriculture / D. Haboudane in Remote sensing of environment, vol 90 n° 3 (15/04/2004)PermalinkClassifying land development in high-resolution panchromatic satellite images using straight-line statistics / C. Unsalan in IEEE Transactions on geoscience and remote sensing, vol 42 n° 4 (April 2004)PermalinkLinear mixture analysis-based compression for hyperspectral image analysis / Q. Du in IEEE Transactions on geoscience and remote sensing, vol 42 n° 4 (April 2004)PermalinkThe determination of the atmospheric optical thickness over western Europe using SeaWiFS imagery / A.A. Kokhanovsky in IEEE Transactions on geoscience and remote sensing, vol 42 n° 4 (April 2004)PermalinkCloud screening in IRS-P4 OCM satellite data: potential of spatial coherence method in the absence of thermal channel information / S.K. Nair in Remote sensing of environment, vol 90 n° 2 (30/03/2004)PermalinkGeometric correction accuracy of IRS-1D PAN imagery using topographic map versus GPS control points / M. Turker in International Journal of Remote Sensing IJRS, vol 25 n° 6 (March 2004)PermalinkIntegrating imaging spectroscopy and neural networks to map grass quality in the Kruger National Park, South Africa / Onisimo Mutanga in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkAutomated extraction of coastline from satellite imagery by integrating canny edge detection and locally adaptative thresholding methods / H. Liu in International Journal of Remote Sensing IJRS, vol 25 n° 5 (March 2004)PermalinkLa télédétection avec ENVI / Françoise de Blomac in SIG la lettre, n° 55 (mars 2004)PermalinkA wavelet approach to road extraction from high spatial resolution remotely-sensed imagery / Qiaoping Zhang in Geomatica, vol 58 n° 1 (March 2004)Permalink