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An unsupervised approach based on the generalized Gaussian model to automatic change detection in multitemporal SAR images / Y. Bazi in IEEE Transactions on geoscience and remote sensing, vol 43 n° 4 (April 2005)
[article]
Titre : An unsupervised approach based on the generalized Gaussian model to automatic change detection in multitemporal SAR images Type de document : Article/Communication Auteurs : Y. Bazi, Auteur ; Lorenzo Bruzzone, Auteur ; F. Melgani, Auteur Année de publication : 2005 Article en page(s) : pp 874 - 887 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] chatoiement
[Termes IGN] détection de changement
[Termes IGN] distribution de Gauss
[Termes IGN] filtrage numérique d'image
[Termes IGN] image ERS-SAR
[Termes IGN] image multitemporelle
[Termes IGN] image radar
[Termes IGN] seuillage d'imageRésumé : (Auteur) In this paper, we present a novel automatic and unsupervised change-detection approach specifically oriented to the analysis of multitemporal single-channel single-polarization synthetic aperture radar (SAR) images. This approach is based on a closed-loop process made up of three main steps: 1) a novel preprocessing based on a controlled adaptive iterative filtering; 2) a comparison between multitemporal images carried out according to a standard log-ratio operator; and 3) a novel approach to the automatic analysis of the log-ratio image for generating the change-detection map. The first step aims at reducing the speckle noise in a controlled way in order to maximize the discrimination capability between changed and unchanged classes. In the second step, the two filtered multitemporal images are compared to generate a log-ratio image that contains explicit information on changed areas. The third step produces the change-detection map according to a thresholding procedure based on a reformulation of the Kittler-Illingworth (KI) threshold selection criterion. In particular, the modified KI criterion is derived under the generalized Gaussian assumption for modeling the distributions of changed and unchanged classes. This parametric model was chosen because it is capable of better fitting the conditional densities of classes in the log-ratio image. In order to control the filtering step and, accordingly, the effects of the filtering process on change-detection accuracy, we propose to identify automatically the optimal number of despeckling filter iterations [Step 1)] by analyzing the behavior of the modified KI criterion. This results in a completely automatic and self-consistent change-detection approach that avoids the use of empirical methods for the selection of the best number of filtering iterations. Experiments carried out on two sets of multitemporal images (characterized by different levels of speckle noise) acquired by the European Remote Sensing 2 satellite SAR sensor confirm the effectiveness of the proposed unsupervised approach, which results in change-detection accuracies very similar to those that can be achieved by a manual supervised thresholding. Numéro de notice : A2005-194 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2004.842441 En ligne : https://doi.org/10.1109/TGRS.2004.842441 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27331
in IEEE Transactions on geoscience and remote sensing > vol 43 n° 4 (April 2005) . - pp 874 - 887[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-05042 RAB Revue Centre de documentation En réserve L003 Disponible Real-time speed limit sign recognition based on locally adaptive thresholding and depth-first-search / J. Wu in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 4 (April 2005)
[article]
Titre : Real-time speed limit sign recognition based on locally adaptive thresholding and depth-first-search Type de document : Article/Communication Auteurs : J. Wu, Auteur ; Y.J. Tsai, Auteur Année de publication : 2005 Article en page(s) : pp 405 - 414 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] acquisition de données
[Termes IGN] image vidéo
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] reconnaissance de caractères
[Termes IGN] réseau routier
[Termes IGN] segmentation d'image
[Termes IGN] seuillage d'image
[Termes IGN] signalisation routière
[Termes IGN] temps réel
[Termes IGN] Visual C++
[Termes IGN] zone d'intérêtRésumé : (Auteur) Stop signs and speed limit signs (SLS) are the most popular and significant traffic signs on roadways. Unlike extracting stop signs with a distinct red color, extracting SLS in a realtime environment is much more challenging. This paper presents an algorithm for recognizing SLS from video imaging and extracting the numerical numbers of SLS to support real-time road inventory data collection operations. The algorithm consists of color segmentation based on locally adaptive thresholding extraction of regions of interest (ROI) using a depth-first-search algorithm, followed by speed limit sign detection and speed limit number extraction by means of optical character recognition and 2D correlation. The algorithm was implemented in Visual C++ language and tested on a non-Hyper-Threading Pentium IV PC with 3.06GHZ CPU using the images taken in the field with different image sizes. The average processing time for an image of 1200 X 800 pixels is about 125 ms. Experimental results from 1,401 video images show 0 percent false positives out of 1,278 images containing no SLS, and 3 percent false negatives out of 123 images containing SLS. Numéro de notice : A2005-159 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.71.4.405 En ligne : https://doi.org/10.14358/PERS.71.4.405 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27297
in Photogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 4 (April 2005) . - pp 405 - 414[article]Remote sensing image thresholding methods for determining landslide activity / P.L. Rosin in International Journal of Remote Sensing IJRS, vol 26 n° 6 (March 2005)
[article]
Titre : Remote sensing image thresholding methods for determining landslide activity Type de document : Article/Communication Auteurs : P.L. Rosin, Auteur ; J. Hervas, Auteur Année de publication : 2005 Article en page(s) : pp 1075 - 1092 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse comparative
[Termes IGN] analyse de groupement
[Termes IGN] effondrement de terrain
[Termes IGN] filtrage numérique d'image
[Termes IGN] image satellite
[Termes IGN] Italie
[Termes IGN] orthorectification
[Termes IGN] seuillage d'imageRésumé : (Auteur) Detecting landslides and monitoring their activity is of great relevance for disastrer prevention, preparedness and mitigation in hilly areas. To this end, change detection techniques were developed and applied to multi-temporal digital aerial photographs, simulating the very high spatial resolution of new satellite sensor optical imagery, over the Tessina complex landslide in north-eastern Italy. Several automatic thresholding algorithms are compared on the difference orthorectified and radiometrically normalized images, including some standard methods based on clustering, statistics, moment and entropy, as well as some more novel techniques previously developed by the authors. In addition, a variety of filters were employed to eliminate much of the underisable residual clutter in the thresholded difference image, mainly as a result of natural vegetation and man-land cover changes. These filters are based on shape and size properties of the connected sets of pixels in the threshold maps. This has enabled us discriminate most ground surface changes related to the movement of a pre-existing landslide. Numéro de notice : A2005-144 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160512331330481 En ligne : https://doi.org/10.1080/01431160512331330481 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27282
in International Journal of Remote Sensing IJRS > vol 26 n° 6 (March 2005) . - pp 1075 - 1092[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-05061 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Automatic detection of earthquake-damaged buildings using DEMs created from pre- and post-earthquake stereo aerial photographs / M. Turker in International Journal of Remote Sensing IJRS, vol 26 n° 4 (February 2005)
[article]
Titre : Automatic detection of earthquake-damaged buildings using DEMs created from pre- and post-earthquake stereo aerial photographs Type de document : Article/Communication Auteurs : M. Turker, Auteur ; B. Cetinkaya, Auteur Année de publication : 2005 Article en page(s) : pp 823 - 832 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse diachronique
[Termes IGN] bati
[Termes IGN] couple stéréoscopique
[Termes IGN] détection automatique
[Termes IGN] dommage matériel
[Termes IGN] hauteur du bâti
[Termes IGN] image numérisée
[Termes IGN] modèle numérique de terrain
[Termes IGN] photographie aérienne
[Termes IGN] séisme
[Termes IGN] seuillage d'image
[Termes IGN] TurquieRésumé : (Auteur) This study presents detection of the collapsed buildings caused by earthquakes using digital elevation models (DEMs) created from pre- and post-earthquake stereo aerial photographs. It is based on the idea that changes in the heights of collapsed buildings can be detected. The study was conducted using aerial photographs taken before (1994) and after (1999) the Izmit earthquake in Turkey. DEMs were created automatically from both pre- and post-earthquake aerial photographs at 5m spatial resolution. The DEMs created from the two epochs were then differenced and the difference DEM obtained was analysed building by building to detect those buildings whose height difference between pre- and post-earthquake exceeded a specified threshold level. The producer's accuracy for detecting the collapsed buildings was found to be 84%. The results show that the difference DEM of the pre- and post-earthquake aerial images can reveal successfully the collapsed buildings caused by the earthquake. It was found that determining an optimum threshold level between change and no change pixels of the difference DEM is important. Numéro de notice : A2005-056 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160512331316810 En ligne : https://doi.org/10.1080/01431160512331316810 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27194
in International Journal of Remote Sensing IJRS > vol 26 n° 4 (February 2005) . - pp 823 - 832[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-05041 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Automated quality control for orthoimages and DEMs / J.K. Höhle in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 1 (January 2005)
[article]
Titre : Automated quality control for orthoimages and DEMs Type de document : Article/Communication Auteurs : J.K. Höhle, Auteur ; Markéta Potůčková, Auteur Année de publication : 2005 Article en page(s) : pp 81 - 87 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] appariement d'images
[Termes IGN] contrôle qualité automatique
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] modèle numérique de surface
[Termes IGN] orthoimage
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] seuillage d'imageRésumé : (Auteur) The checking of the geometric accuracy of orthoimages and digital elevation models (DEMs) is discussed. As a reference, an existing orthoimage and a second orthoimage derived from an overlapping aerial image, are used. The proposed automated procedures for checking the orthoimages and DEMs are based on matching of corresponding image patches. Existing topographic databases are additionally used in order to select time-invariant objects as checkpoints. In order to avoid blunders in the correlation, thresholds for similarity measures are applied. Detailed studies show that a combination of thresholds for the maximum correlation coefficient, the average mutual information, and distance can reduce the number of blunders in the automated measurements considerably and should therefore be applied. The calculation of DEM errors is carried out by an improved-formula. The new methods and procedures are applied to two practical examples, and the results are presented. Numéro de notice : A2005-012 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.71.1.81 En ligne : https://doi.org/10.14358/PERS.71.1.81 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27151
in Photogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 1 (January 2005) . - pp 81 - 87[article]Road extraction using SVM and image segmentation / M. Song in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 12 (December 2004)PermalinkComparison 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)PermalinkCouplage de données optiques et radar pour la caractérisation de paysages urbains amazoniens : application à l'île de Cayenne / Jean-François Faure in Revue internationale de géomatique, vol 14 n° 3 - 4 (septembre 2004 – février 2005)PermalinkMonitoring surface soil moisture in post-harvest rice areas using C-band radar imagery in NorthEast Thailand / S. Kaojarern in Geocarto international, vol 19 n° 3 (September - November 2004)PermalinkNighttime polar cloud detection with MODIS / Y. Liu in Remote sensing of environment, vol 92 n° 2 (15/08/2004)PermalinkDerivation of a threshold function for the advanced very high resolution radiometer 3, 75um channel and its application in automatic cloud discrimination over snow/ice surfaces / X. Xiong in International Journal of Remote Sensing IJRS, vol 25 n° 15 (August 2004)PermalinkChange detection techniques / Dong Lu in International Journal of Remote Sensing IJRS, vol 25 n° 12 (June 2004)PermalinkCartographie de la densité du bâti par analyse granulométrique des images de télédetection / Franck Chopin in Revue Française de Photogrammétrie et de Télédétection, n°173-174 (Juin 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)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)PermalinkQualité des eaux superficielles et assolement dans le bassin versant du Madon (Lorraine) / F. Masutti (2004)PermalinkWavelets applied to simplification of digital terrain models / J.T. Bjorke in International journal of geographical information science IJGIS, vol 17 n° 7 (october 2003)PermalinkDynamique des marais salés et changements environnementaux / Frédéric Bertrand in Photo interprétation, vol 39 n° 3 - 4 (Septembre 2003)PermalinkA comparative analysis of scanned maps and imagery for mapping applications / Costas Armenakis in ISPRS Journal of photogrammetry and remote sensing, vol 57 n° 5-6 (April - May 2003)PermalinkL'évaluation de la généralisation / Sylvain Bard in Géomatique expert, n° 22 (01/01/2003)PermalinkPluriGaussian simulations in geosciences with cd-rom / M. Armstrong (2003)PermalinkTraitement et analyse des images numériques / S. Bres (2003)PermalinkChange detection for thematic mapping by means of airborne multitemporal polarimetric SAR imagery / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 40 n° 3 (March 2002)PermalinkGeostatistical modelling of spatial uncertainty using P-field simulation with conditional probability fields / P. Goovaerts in International journal of geographical information science IJGIS, vol 16 n° 2 (march 2002)PermalinkDevelopment of daily spatial heat unit mapping from monthly climatic surfaces for the Australian continent / Nicholas C. Coops in International journal of geographical information science IJGIS, vol 15 n° 4 (june 2001)Permalink