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Some issues in the classification of DAIS hyperspectral data / M. Pal in International Journal of Remote Sensing IJRS, vol 27 n°12-13-14 (July 2006)
[article]
Titre : Some issues in the classification of DAIS hyperspectral data Type de document : Article/Communication Auteurs : M. Pal, Auteur ; Paul M. Mather, Auteur Année de publication : 2006 Article en page(s) : pp 2895 - 2916 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] classificateur paramétrique
[Termes IGN] classification dirigée
[Termes IGN] classification par arbre de décision
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] classification par réseau neuronal
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] Espagne
[Termes IGN] image DAIS
[Termes IGN] image hyperspectrale
[Termes IGN] précision de la classification
[Termes IGN] qualité du processus
[Termes IGN] transformation orthogonaleRésumé : (Auteur) Classification accuracy depends on a number of factors, of which the nature of the training samples, the number of bands used, the number of classes to be identified relative to the spatial resolution of the image and the properties of the classifier are the most important. This paper evaluates the effects of these factors on classification accuracy using a test area in La Mancha, Spain. High spectral and spatial resolution DAIS data were used to compare the performance of four classification procedures (maximum likelihood, neural network, support vector machines and decision tree). There was no evidence to support the view that classification accuracy inevitably declines as the data dimensionality increases. The support vector machine classifier performed well with all test data sets. The use of the orthogonal MNF transform resulted in a decline in classification accuracy. However, the decision-tree approach to feature selection worked well. Small increases in classifier accuracy may be obtained using more sophisticated techniques, but it is suggested here that greater attention should be given to the collection of training and test data that represent the range of land surface variability at the spatial scale of the image. Copyright Taylor & Francis Numéro de notice : A2006-309 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500185227 En ligne : https://doi.org/10.1080/01431160500185227 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28033
in International Journal of Remote Sensing IJRS > vol 27 n°12-13-14 (July 2006) . - pp 2895 - 2916[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-06071 RAB Revue Centre de documentation En réserve L003 Disponible Study of tectonics in relation to the seismic activity of the Davalt area, Nasik district, Maharashtra, India using remote sensing and GIS techniques / J. Sarup in International Journal of Remote Sensing IJRS, vol 27 n°12-13-14 (July 2006)
[article]
Titre : Study of tectonics in relation to the seismic activity of the Davalt area, Nasik district, Maharashtra, India using remote sensing and GIS techniques Type de document : Article/Communication Auteurs : J. Sarup, Auteur ; M. Muthukumaran, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 2371 - 2387 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] classification dirigée
[Termes IGN] géologie locale
[Termes IGN] géomorphologie locale
[Termes IGN] image IRS
[Termes IGN] image multitemporelle
[Termes IGN] Inde
[Termes IGN] séisme
[Termes IGN] système d'information géographique
[Termes IGN] tectoniqueRésumé : (Auteur) Well-documented geological data (from both field and satellite) in the Deccan Volcanic Provinces (DVP) in and around the Dalvat region, Nasik District, India has been analysed by Geographic Information System (GIS) techniques and reported in this paper so as to relate the geology and structures with recent seismicity. It has been the belief among earth scientists that the Deccan Traps in Maharashtra, India is tectonically stable as the region attained solidity long ago. However, recent activity in the study area altered this concept and it is now accepted that seismic activity is still continuing on a mild scale. As such, the need has arisen to take into consideration historical as well as recent geological data to study in detail the tectonic setup in the Deccan Traps.
Using the well-known relationship between the shear zone, lineaments, and geomorphology, and incorporating these with tectonic events, an attempt has been made to explore the geology and structures in and around the Dalvat region. Field observations and signatures on remote sensing data show that there is evidence of fault traces in the form of shear zones and slickensides in the Deccan Traps near the Kosurde, Dhanoli, Chikhli, and Manchandar villages of the Nasik District. The study has further been incorporated with seismic density data. Magnitudes of 3.9 were recorded as the maximum micro-epicentres, and they fell on the shear fractures detected in the area of study.
In order to identify seismically vulnerable areas, seismic hazard zonation (SHZ) mapping has been carried out. Different data layers, including structural, lithological, geomorphological, drainage, and soil have been visually interpreted, scanned, and rectified. A rose diagram of the lineaments shows trends in the NNE–SSW to NS falling on major seismic zones of the study area, showing weaker zones beneath the surface. Raster images were digitized for conversion to a vector coverage using ERDAS 8.6. and ArcGIS 8.3. The ordinal scale (qualitative) relative weighting rating technique was used to give a seismic hazard index (SHI) value to delineate various seismic hazard zones; namely very low, low, moderate, high, and very high. Copyright Taylor & FrancisNuméro de notice : A2006-306 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500497846 En ligne : https://doi.org/10.1080/01431160500497846 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28030
in International Journal of Remote Sensing IJRS > vol 27 n°12-13-14 (July 2006) . - pp 2371 - 2387[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-06071 RAB Revue Centre de documentation En réserve L003 Disponible A technique for generating natural colour images from false colour composite images / S.K. Patra in International Journal of Remote Sensing IJRS, vol 27 n°12-13-14 (July 2006)
[article]
Titre : A technique for generating natural colour images from false colour composite images Type de document : Article/Communication Auteurs : S.K. Patra, Auteur ; M. Shekher, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 2977 - 2989 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] bande spectrale
[Termes IGN] couleur (variable spectrale)
[Termes IGN] couleur à l'écran
[Termes IGN] image en couleur composée
[Termes IGN] point d'appui
[Termes IGN] superposition d'imagesRésumé : (Auteur) Colour is widely used in remote sensing work. In many instances, the use of colour conveys additional information both visually and scientifically. Remote sensing satellites view the earth in different spectral bands, viz. near infrared (NIR), red, green, and blue bands, in a conventional multispectral imaging system. In the absence of a blue channel, colour images can be generated using near infrared, red, and green bands in what is known as a false colour composite (FCC) and does not look natural, like the image we see with the naked eye. For a trained interpreter, this does not pose any problems. However, when the intended use is a fly-through of a draped terrain, visual interpretation, or a display, meant for the non-remote sensing professional, this becomes a handicap. To overcome this, there is a requirement to generate natural colour composites (NCC) from the given false colour composite, which demands the simulation of a blue band to be combined with green and red bands. This paper describes a unique method of generating a blue band to form natural colour images from a given false colour image set. We use a spectral transformation method to establish a relationship between the false colour and true colour image pairs provided by a sensor with all the four bands, which has a broader spectral coverage. A transformation function is fitted by selecting radiometric control points along the line of geometric registration to find a set of coefficients to be used for simulating a blue band. This blue band, along with the green and red bands, provides a near true colour or ‘natural colour’ on the display. In this paper, we present a set of adjustable radiometric transformation coefficients to accommodate variation in spatial and dynamic range offered by sensors to generate natural colour. These coefficients seem to work on a large number of images of different seasons, provided similar spectral bands and terrain are used. The proposed ‘natural colour generator’ can be used in changing false colour images to natural colour images with the aim of ‘what you get is what you would have seen’. Copyright Taylor & Francis Numéro de notice : A2006-311 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160600554322 En ligne : https://doi.org/10.1080/01431160600554322 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28035
in International Journal of Remote Sensing IJRS > vol 27 n°12-13-14 (July 2006) . - pp 2977 - 2989[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-06071 RAB Revue Centre de documentation En réserve L003 Disponible Angular resolution of terrestrial laser scanners / Derek D. Lichti in Photogrammetric record, vol 21 n° 114 (June - August 2006)
[article]
Titre : Angular resolution of terrestrial laser scanners Type de document : Article/Communication Auteurs : Derek D. Lichti, Auteur ; S. Jamtsho, Auteur Année de publication : 2006 Article en page(s) : pp 141 - 160 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] crénelage
[Termes IGN] dégradation d'image
[Termes IGN] échantillonnage d'image
[Termes IGN] fonction de transfert de modulation
[Termes IGN] incertitude de position
[Termes IGN] indicateur de résolution
[Termes IGN] limite de résolution géométrique
[Termes IGN] modélisation 3D
[Termes IGN] semis de points
[Termes IGN] signal laser
[Termes IGN] télémètre laser terrestreRésumé : (Auteur) II est nécessaire de connaître la résolution spatiale des scanneurs à laser pour éviter des dégradations de type aliasing et estimer le niveau de détail que l'on peut obtenir à partir d'un nuage de points scannés. On peut identifier dans la résolution spatiale une composante en distance et une angulaire. Cette dernière, qui fait l'objet de cet article, est essentiellement tributaire de l'intervalle d'échantillonnage et de la largeur du faisceau laser. Mais on considère généralement que c'est seulement l'intervalle d'échantillonnage qui constitue l'indicateur unique de résolution. Or les deux facteurs affectent la résolution de tout nuage de points scannés, de sorte que si l'on en examine un indépendamment de l'autre, on peut aboutir à une mauvaise estimation des possibilités du système. On a même pu démontrer que c'était tout à fait inadéquat, sauf dans certains cas particuliers. C'est pourquoi on propose un nouveau moyen, mieux adapté, pour déterminer la résolution des scanneurs à laser, en se basant sur le cône d'analyse instantané efficace (EIFOV). On dérive ce dernier par une modélisation faisant intervenir la variance de glissement du processus incrémental d'échantillonnage équi-angulaire, l'incertitude du positionnement provoqué par la largeur du faisceau laser et la quantification angulaire observée et en mêlant les fonctions de transfert de modulation moyennes de l'ensemble (AMTFs). On a ainsi pu modéliser et analyser plusieurs systèmes de scanneurs terrestres à laser du commerce en ce qui concerne leurs possibilités de résolution angulaire grâce à cette notion d'ElFOV. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2006-192 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2006.00367.x En ligne : https://doi.org/10.1111/j.1477-9730.2006.00367.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27919
in Photogrammetric record > vol 21 n° 114 (June - August 2006) . - pp 141 - 160[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-06021 RAB Revue Centre de documentation En réserve L003 Disponible Co-registration and inter-sensor comparison of MODIS and LANDSAT 7 ETM+ data aimed at NDVI calculation / P. Boccardo in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)
[article]
Titre : Co-registration and inter-sensor comparison of MODIS and LANDSAT 7 ETM+ data aimed at NDVI calculation Type de document : Article/Communication Auteurs : P. Boccardo, Auteur ; Enrico Borgogno Mondino, Auteur ; et al., Auteur Année de publication : 2006 Conférence : ISPRS 2006, Commission 1 Symposium, From sensors to imagery 03/07/2006 06/07/2006 Champs-sur-Marne [Paris Marne-la-Vallée] France OA ISPRS Archives Article en page(s) : pp 74 - 79 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] erreur systématique
[Termes IGN] homologie
[Termes IGN] image Landsat-ETM+
[Termes IGN] image Terra-MODIS
[Termes IGN] limite de résolution géométrique
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] superposition d'imagesRésumé : (Auteur) To evaluate accuracy of low resolution vegetation mapping for hydrological purposes, a comparative study of NDVI images derived from MODIS and Landsat 7 ETM+ data has been done. Main goal is to understand how effective MODIS images can be for vegetation characterization on large areas, as compared to the Landsat 7 ETM+ ones. In this paper a methodology is proposed with the aim of measuring the difference between NDVI values derived from the two different data, considering synthetic parameters and investigating their dependency on the geometric resolution of the images. Great attention was paid to the problem of the geometric co-registration of the two types of data. This is a very sensitive parameter for the subsequent analysis. A mixed approach was adopted: images were firstly orthoprojected to eliminate sensor geometry and relief displacement effects; subsequently, a refining image-to-image co-registration procedure was carried out through a homographic transformation implemented in a self-developed routine. Two pairs of contemporary images (MODIS and Landsat 7) were used as benchmarks for our tests. Simplified procedures aimed at calibrating images and at removing atmospheric noise were performed. The resulting corrected images were used to calculate NDVI images. These ones (two pairs) were then compared through a statistical approach in order to investigate how a different geometric resolution can influence the NDVI values. The proposed approach is not a traditional image based (matrix comparison) but a new one. NDVI value correspondences were considered between the MODIS pixel and the group of Landsat pixels belonging to the polygon which represents the considered MODIS pixel in the Landsat image space. Statistics extracted on-the-fly from these Landsat pixels were used to investigate in depth the relationship between them and NDVI value of the corresponding MODIS pixel. NDVI differences were calculated between the single NDVI MODIS values and a synthetic parameter (mean value) of the homologous Landsat pixel group. A direct comparison between the NDVI values obtained from MODIS and Landsat 7 images has shown a systematic error that can be read as bias (MODIS NDVI over estimation). This led the authors to determine a suitable model in order to eliminate the bias, whose presence would have conditioned later comparisons. Original MODIS image was then corrected through the defined model. This has been designed to be suitable for any MODIS image acquired over the same area (parameterization was used). New NDVI differences were calculated using the corrected MODIS images and the previous Landsat 7 ones. In order to investigate the nature of the residual differences and to try to recognize the critical MODIS pixels, some considerations were made concerning the statistics of each corresponding group of Landsat pixels. A classification of the MODIS pixel was generated according to the behaviour of their differences with respect to the adopted statistics. Copyright SFPT Numéro de notice : A2006-624 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : sans En ligne : https://www.isprs.org/proceedings/XXXVI/part1/Papers/PS1-04.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28347
in Revue Française de Photogrammétrie et de Télédétection > n° 182 (Juin 2006) . - pp 74 - 79[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 018-06021 RAB Revue Centre de documentation En réserve L003 Disponible Enhancing a sequence of facial images combining multiple undersampled and compressed images / G. Scarmana in Photogrammetric record, vol 21 n° 114 (June - August 2006)PermalinkMatching topographic surfaces : application to lidar and photogrammetric surfaces / Frédéric Bretar in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)PermalinkA new intensity-hue-saturation fusion approach to image fusion with a tradeoff parameter / M. Choi in IEEE Transactions on geoscience and remote sensing, vol 44 n° 6 (June 2006)PermalinkLe symposium de l'ISPRS / Anonyme in Géomatique expert, n° 51 (01/06/2006)PermalinkUtilisation des images satellites à haute résolution pour la surveillance d'une zone côtière / Valerio Baiocchi in Géomatique expert, n° 51 (01/06/2006)PermalinkHigh-resolution image fusion: methods to preserve spectral and spatial resolution / A. Svab in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 5 (May 2006)PermalinkMTF-tailored multiscale fusion of high-resolution multispectral and panchromatic imagery / B. Aiazzi in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 5 (May 2006)PermalinkConsideration of smoothing techniques for hyperspectral remote sensing / C. Vaiphasa in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 2 (April 2006)PermalinkDetermination and improvement of spatial resolution of the CCD-line-scanner system ADS40 / R. Reulke in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 2 (April 2006)PermalinkRelevance of hyperspectral data for natural resources management / T.V. Ramachandra in GIS development, vol 10 n° 4 (April 2006)Permalink