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A comparison of usefulness of 2D and 3D representations of urban planning / Grant Herbert in Cartography and Geographic Information Science, Vol 42 n° 1 (January 2015)
[article]
Titre : A comparison of usefulness of 2D and 3D representations of urban planning Type de document : Article/Communication Auteurs : Grant Herbert, Auteur ; Xuwei Chen, Auteur Année de publication : 2015 Article en page(s) : pp 22 - 32 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] analyse comparative
[Termes IGN] Nouvelle-Zélande
[Termes IGN] ombre
[Termes IGN] représentation cartographique 2D
[Termes IGN] représentation cartographique 3D
[Termes IGN] urbanisme
[Termes IGN] visualisation
[Termes IGN] visualisation 3DRésumé : (auteur) Very little existing literature has addressed the issues of the perceived usefulness of 3D visualizations over 2D and the use of cartographic shadow representations in the planning community. Urban planning has moved toward a 3D, geographic-information-system-centric, and functional decision support framework. This study aims to examine the preferences of urban planning professionals with respect to 2D and 3D visualizations in a case study. The authors built a 3D representation of a proposed building along with the existing urban environment in Queenstown, New Zealand and conducted a usefulness test through a survey and interview. Based on the survey, the study evaluated the degree of task utility perceived in each visualization method, the effect on the mental image, and shadow representation preferences. The findings support the literature that the benefits of using a 2D or 3D model are closely related to the types of planning tasks undertaken. The findings also reveal a complex view of planning activities, suggesting that planners themselves cannot be treated as a single group for research purposes. Numéro de notice : A2015-231 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/15230406.2014.987694 En ligne : https://doi.org/10.1080/15230406.2014.987694 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76223
in Cartography and Geographic Information Science > Vol 42 n° 1 (January 2015) . - pp 22 - 32[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-2015011 RAB Revue Centre de documentation En réserve L003 Disponible Perceptually shaded slope maps for the visualization of digital surface models / Thomas J. Pingel in Cartographica, vol 49 n° 4 (Winter 2014)
[article]
Titre : Perceptually shaded slope maps for the visualization of digital surface models Type de document : Article/Communication Auteurs : Thomas J. Pingel, Auteur ; Keith C. Clarke, Auteur Année de publication : 2014 Article en page(s) : pp 225 - 240 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] analyse visuelle
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] estompage automatique
[Termes IGN] lisibilité perceptive
[Termes IGN] modèle numérique de surface
[Termes IGN] ombre
[Termes IGN] relief
[Termes IGN] représentation du relief
[Termes IGN] visualisation de donnéesRésumé : (Auteur) Although shaded relief, or hillshaded, images are a widely used method to represent high-resolution (~1-m) digital surfaces derived from airborne laser (or LiDAR) scans, such displays may become difficult to interpret when they include surface features like buildings, roadways, and natural vegetation. One possible alternative as a visualization of such surface models is a representation based on slope shading – the steeper, the darker – but attenuated to the perceptual bias of overestimation of slope. The empirical work presented here demonstrates that Perceptually Shaded Slope Maps (PSSMs) perform as well or better than either hillshaded or hypsometric images on map-reading tasks, including profile estimation and mental rotation. Numéro de notice : A2014-650 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.3138/carto.49.4.2141 En ligne : http://dx.doi.org/10.3138/carto.49.4.2141 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75098
in Cartographica > vol 49 n° 4 (Winter 2014) . - pp 225 - 240[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 031-2014041 RAB Revue Centre de documentation En réserve L003 Disponible Changing the light azimuth in shaded relief representation by clustering aspect / Fabio Veronesi in Cartographic journal (the), vol 51 n° 4 (November 2014)
[article]
Titre : Changing the light azimuth in shaded relief representation by clustering aspect Type de document : Article/Communication Auteurs : Fabio Veronesi, Auteur ; Lorenz Hurni, Auteur Année de publication : 2014 Article en page(s) : pp 291 - 300 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Rédaction cartographique
[Termes IGN] ArcGIS
[Termes IGN] estompage automatique
[Termes IGN] ombre
[Termes IGN] représentation du relief
[Termes IGN] segmentation d'image
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Manual shading, traditionally produced manually by specifically trained cartographers, is still considered superior to automatic methods, particularly for mountainous landscapes. However, manual shading is time-consuming and its results depend on the cartographer and as such difficult to replicate consistently. For this reason there is a need to create an automatic method to standardize its results. A crucial aspect of manual shading is the continuous change of light direction (azimuth) and angle (zenith) in order to better highlight discrete landforms. Automatic hillshading algorithms, widely available in many geographic information systems (GIS) applications, do not provide this feature. This may cause the resulting shaded relief to appear flat in some areas, particularly in areas where the light source is parallel to the mountain ridge. In this work we present a GIS tool to enhance the visual quality of hillshading. We developed a technique based on clustering aspect to provide a seamless change of lighting throughout the scene. We also provide tools to change the light zenith according to either elevation or slope. This way the cartographer has more room for customizing the shaded relief representation. Moreover, the method is completely automatic and this guarantees consistent and reproducible results. This method has been embedded into an ArcGIS toolbox. Numéro de notice : A2014-641 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/1743277414Y.0000000100 En ligne : https://doi.org/10.1179/1743277414Y.0000000100 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75086
in Cartographic journal (the) > vol 51 n° 4 (November 2014) . - pp 291 - 300[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 030-2014041 RAB Revue Centre de documentation En réserve L003 Disponible Restoration of information obscured by mountainous shadows through Landsat TM/ETM+ images without the use of DEM data : A new method / Yuan Zhou in IEEE Transactions on geoscience and remote sensing, vol 52 n° 1 tome 1 (January 2014)
[article]
Titre : Restoration of information obscured by mountainous shadows through Landsat TM/ETM+ images without the use of DEM data : A new method Type de document : Article/Communication Auteurs : Yuan Zhou, Auteur ; Jin Chen, Auteur ; Qinghua Guo, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 313 - 328 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] image Landsat-ETM+
[Termes IGN] image Landsat-TM
[Termes IGN] montagne
[Termes IGN] ombre
[Termes IGN] pixel
[Termes IGN] plus proche voisin, algorithme du
[Termes IGN] restauration d'image
[Termes IGN] valeur radiométriqueRésumé : (Auteur) Shadows in remotely sensed imagery occur when objects totally or partially occlude direct light from a source of illumination, generating great difficulty in land cover interpretation and classification because of the loss of spectral information of shaded pixels. In a mountainous environment with rough terrain, shadows are especially pronounced due to the differentiation of direct illumination between sunny and shady slopes. Topographic correction methods, which are widely used to adjust for differences in solar incidence angles, can partly alleviate the impacts of shadows. However, there are two limitations: one is that the contemporary topographic corrections have little effect on areas that have very low incidence angles and areas that are completely without direct solar illumination (cast shadow); another is that their effectiveness is restricted by the data quality and completeness, spatial resolution, and elevation accuracy of the Digital Elevation Model (DEM) data, which is not currently available in all parts of the world. Thus, noise and errors may be introduced in topographic correction during resampling and geometric registration of the target image. This paper proposes a new approach to restore the radiometric information of mountainous cast shadows using a spectral processing technique called “continuum removal” (CR) without the aid of DEM. The CR-based approach makes full use of the spectral information derived from both the shaded pixels and their neighboring nonshaded pixels of the same land cover type. Several Landsat TM images were used to assess the performance of the proposed method. Results indicated that the proposed method can effectively restore the spectral values of shaded pixels more accurately than the ATCOR_3 correction method, especially for very low incidence angle areas and cast shadows. By comparing data values of shaded pixels with nonshaded pixels (pure reference pixels) of their same class, images processed by the proposed method had the lowest average root mean square error (RMSE) between them in visible, NIR and SWIR bands, followed by the ATCOR_3 correction method and the original image. In addition, the proposed method achieved the best classification accuracy, higher than those from the original test image and the ATCOR_3 corrected image generated using 90 m or 30 m spatial resolution DEM. Therefore, the Continuum Removal method is a better alternative for restoring objects obscured by mountainous shadow when adequate DEM data are unavailable and the quality of DEM cannot satisfy the requirements of topographic correction algorithms. Numéro de notice : A2014-037 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2239651 En ligne : https://doi.org/10.1109/TGRS.2013.2239651 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32942
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 1 tome 1 (January 2014) . - pp 313 - 328[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014011A RAB Revue Centre de documentation En réserve L003 Disponible Automated detection of buildings from single VHR multispectral images using shadow information and graph cuts / Ali Ozgun Ok in ISPRS Journal of photogrammetry and remote sensing, vol 86 (December 2013)
[article]
Titre : Automated detection of buildings from single VHR multispectral images using shadow information and graph cuts Type de document : Article/Communication Auteurs : Ali Ozgun Ok, Auteur Année de publication : 2013 Article en page(s) : pp 21 - 40 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] détection de régions
[Termes IGN] détection du bâti
[Termes IGN] image à très haute résolution
[Termes IGN] image Geoeye
[Termes IGN] image multibande
[Termes IGN] ombre
[Termes IGN] segmentation d'imageRésumé : (Auteur) In this study, we propose a novel methodology for automated detection of buildings from single very-high-resolution (VHR) multispectral images. The methodology uses the principal evidence of buildings: the shadows that they cast. We model the directional spatial relationship between buildings and their shadows using a recently proposed probabilistic landscape approach. An effective shadow post-processing step is developed to focus on landscapes that belong to building regions. The building regions are detected using an original two-level graph theory approach. In the first level, each shadow region is addressed separately, and building regions are identified via iterative graph cuts designed in two-label partitioning. The final building regions are characterised in a second level in which the previously labelled building regions are subjected to a single-step multi-label graph optimisation performed over the entire image domain. Numerical assessments performed on 16 VHR GeoEye-1 images demonstrate that the proposed approach is highly robust and reliable. A distinctive specialty of the proposed approach is its applicability to buildings with diverse characteristics as well as to VHR images with significantly different illumination properties. Numéro de notice : A2013-703 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.09.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.09.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32839
in ISPRS Journal of photogrammetry and remote sensing > vol 86 (December 2013) . - pp 21 - 40[article]Use of shadows for detection of earthquake-induced collapsed buildings in high-resolution satellite imagery / Xiaohua Tong in ISPRS Journal of photogrammetry and remote sensing, vol 79 (May 2013)PermalinkDescription de la campagne aéroportée UMBRA : étude de l'impact anthropique sur les écosystèmes urnbains et naturels avec des images THR multispectrales et hyperspectrales / Karine R.M. Adeline in Revue Française de Photogrammétrie et de Télédétection, n° 202 (Avril 2013)PermalinkAutomated detection of arbitrarily shaped buildings in complex environments from monocular VHR optical satellite imagery / Ali Ozgun Ok in IEEE Transactions on geoscience and remote sensing, vol 51 n° 3 Tome 2 (March 2013)PermalinkMaterial reflectance retrieval in urban tree shadows with physics-based empirical atmospheric correction / Karine R.M. Adeline (2013)PermalinkA new 3-D solar radiation model for 3-D city models / Jaroslav Hofierka in Transactions in GIS, vol 16 n° 5 (October 2012)PermalinkVisualisation 3D de terrain texturé : préservation au niveau du pixel des qualités géométriques et colorimétriques, une méthode temps réel, innovante et simple / T.V. Lê in Revue internationale de géomatique, vol 22 n° 3 (septembre - novembre 2012)PermalinkEvaluating classification techniques for mapping vertical geology using field-based hyperspectral sensors / R.J. Murphy in IEEE Transactions on geoscience and remote sensing, vol 50 n° 8 (August 2012)PermalinkMultidirectional visibility index for analytical shading enhancement / T. Podobnikar in Cartographic journal (the), vol 49 n° 3 (August 2012)PermalinkSpatio-temporal MODIS EVI gap filling under cloud cover: An example in Scotland / L. Poggio in ISPRS Journal of photogrammetry and remote sensing, vol 72 (August 2012)PermalinkSt-Charles Parish and GNSS signal shadow issues: Satellite shadow reduction technology / K. Corbley in Geoinformatics, vol 15 n° 4 (01/06/2012)PermalinkReducing mis-registration and shadow effects on change detection in wetlands / Jinxia Zhu in Photogrammetric Engineering & Remote Sensing, PERS, vol 77 n° 4 (April 2011)PermalinkUse of high-resolution satellite imagery in an integrated model to predict the distribution of shade coffee tree hybrid zones / C. Gomez in Remote sensing of environment, vol 114 n° 11 (15/11/2010)PermalinkThe building shadow problem of airborne lidar / T.Y. Shih in Photogrammetric record, vol 24 n° 128 (December 2009 - February 2010)PermalinkUse Markov random fields for automatic cloud-shadow detection on high resolution / Sylvie Le Hégarat-Mascle in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 4 (July - August 2009)PermalinkHigh-sensitivity GPS: an availability, reliability and accuracy test / V. Schweiger in Bulletin des sciences géographiques, n° 23 (juin 2009)PermalinkPermalinkExtraction of land cover themes from aerial ortho-images in mountainous areas using external information / Arnaud Le Bris in Photogrammetric record, vol 23 n° 124 (December 2008 - February 2009)PermalinkInteractive responses of Quercus suber L. seedlings to light and mild water stress: effects on morphology and gas exchange traits / Jaime Puértolas in Annals of Forest Science, Vol 65 n° 6 (September 2008)PermalinkIntegrated use of SRM, Landsat ETM+ data and 3D perspective views to identify the tectonic geomorphology of Dehradun valley, India / A.K. Singh in International Journal of Remote Sensing IJRS, vol 28 n°11-12 (June 2007)PermalinkExtraction of landcover themes out of aerial orthoimages in mountainous areas using external information / Arnaud Le Bris (2007)Permalink