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A parallel scheme for large-scale polygon rasterization on CUDA-enabled GPUs / Chen Zhou in Transactions in GIS, vol 21 n° 3 (June 2017)
[article]
Titre : A parallel scheme for large-scale polygon rasterization on CUDA-enabled GPUs Type de document : Article/Communication Auteurs : Chen Zhou, Auteur ; Zhenjie Chen, Auteur ; Yuzhe Pian, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 608 – 631 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] données massives
[Termes IGN] maillage
[Termes IGN] polygone
[Termes IGN] processeur
[Termes IGN] processeur graphique
[Termes IGN] rastérisation
[Termes IGN] temps
[Termes IGN] traitement parallèleRésumé : (Auteur) This research develops a parallel scheme to adopt multiple graphics processing units (GPUs) to accelerate large-scale polygon rasterization. Three new parallel strategies are proposed. First, a decomposition strategy considering the calculation complexity of polygons and limited GPU memory is developed to achieve balanced workloads among multiple GPUs. Second, a parallel CPU/GPU scheduling strategy is proposed to conceal the data read/write times. The CPU is engaged with data reads/writes while the GPU rasterizes the polygons in parallel. This strategy can save considerable time spent in reading and writing, further improving the parallel efficiency. Third, a strategy for utilizing the GPU's internal memory and cache is proposed to reduce the time required to access the data. The parallel boundary algebra filling (BAF) algorithm is implemented using the programming models of compute unified device architecture (CUDA), message passing interface (MPI), and open multi-processing (OpenMP). Experimental results confirm that the implemented parallel algorithm delivers apparent acceleration when a massive dataset is addressed (50.32 GB with approximately 1.3 × 108 polygons), reducing conversion time from 25.43 to 0.69 h, and obtaining a speedup ratio of 36.91. The proposed parallel strategies outperform the conventional method and can be effectively extended to a CPU-based environment. Numéro de notice : A2017-626 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12213 En ligne : http://dx.doi.org/10.1111/tgis.12213 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86941
in Transactions in GIS > vol 21 n° 3 (June 2017) . - pp 608 – 631[article]Total 3D-viewshed map : quantifying the visible volume in digital elevation models / Antonio Rodriguez Cervilla in Transactions in GIS, vol 21 n° 3 (June 2017)
[article]
Titre : Total 3D-viewshed map : quantifying the visible volume in digital elevation models Type de document : Article/Communication Auteurs : Antonio Rodriguez Cervilla, Auteur ; Siham Tabik, Auteur ; Jesús Vías, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 591 - 607 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] densité du bâti
[Termes IGN] données localisées 3D
[Termes IGN] lasergrammétrie
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique du bâti
[Termes IGN] perception
[Termes IGN] système d'information géographique
[Termes IGN] volume (grandeur)Résumé : (Auteur) The 3D perception of the human eye is more impressive in irregular land surfaces than in flat land surfaces. The quantification of this perception would be very useful in many applications. This article presents the first approach to determining the visible volume, which we call the 3D-viewshed, in each and all the points of a DEM (Digital Elevation Model). Most previous visibility algorithms in GIS (Geographic Information Systems) are based on the concept of a 2D-viewshed, which determines the number of points that can be seen from an observer in a DEM. Extending such a 2D-viewshed to 3D space, then to all the DEM-points, is too expensive computationally since the viewshed computation per se is costly. In this work, we propose the first approach to compute a new visibility metric that quantifies the visible volume from every point of a DEM. In particular, we developed an efficient algorithm with a high data and calculation re-utilization. This article presents the first total-3D-viewshed maps together with validation results and comparative analysis. Using our highly scalable parallel algorithm to compute the total-3D-viewshed of a DEM with 4 million points on a Xeon Processor E5-2698 takes only 1.3 minutes. Numéro de notice : A2017-625 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12216 En ligne : http://dx.doi.org/10.1111/tgis.12216 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86940
in Transactions in GIS > vol 21 n° 3 (June 2017) . - pp 591 - 607[article]A simplified linear feature matching method using decision tree analysis, weighted linear directional mean, and topological relationships / Ick-Hoi Kim in International journal of geographical information science IJGIS, vol 31 n° 5-6 (May-June 2017)
[article]
Titre : A simplified linear feature matching method using decision tree analysis, weighted linear directional mean, and topological relationships Type de document : Article/Communication Auteurs : Ick-Hoi Kim, Auteur ; Chen-Chieh Feng, Auteur ; Yi-Chen Wang, Auteur Année de publication : 2017 Article en page(s) : pp 1042 - 1060 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] appariement de données localisées
[Termes IGN] axe médian
[Termes IGN] base de données historiques
[Termes IGN] classification par arbre de décision
[Termes IGN] conflation
[Termes IGN] distance de Hausdorff
[Termes IGN] données anciennes
[Termes IGN] objet géographique linéaire
[Termes IGN] relation topologique
[Termes IGN] réseau routier
[Termes IGN] similitude
[Termes IGN] valeur moyenneRésumé : (auteur) Linear feature matching is one of the crucial components for data conflation that sees its usefulness in updating existing data through the integration of newer data and in evaluating data accuracy. This article presents a simplified linear feature matching method to conflate historical and current road data. To measure the similarity, the shorter line median Hausdorff distance (SMHD), the absolute value of cosine similarity (aCS) of the weighted linear directional mean values, and topological relationships are adopted. The decision tree analysis is employed to derive thresholds for the SMHD and the aCS. To demonstrate the usefulness of the simple linear feature matching method, four models with incremental configurations are designed and tested: (1) Model 1: one-to-one matching based on the SMHD; (2) Model 2: matching with only the SMHD threshold; (3) Model 3: matching with the SMHD and the aCS thresholds; and (4) Model 4: matching with the SMHD, the aCS, and topological relationships. These experiments suggest that Model 2, which considers only distance, does not provide stable results, while Models 3 and 4, which consider direction and topological relationships, produce stable results with levels of accuracy around 90% and 95%, respectively. The results suggest that the proposed method is simple yet robust for linear feature matching. Numéro de notice : A2017-241 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2016.1267736 En ligne : http://dx.doi.org/10.1080/13658816.2016.1267736 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85177
in International journal of geographical information science IJGIS > vol 31 n° 5-6 (May-June 2017) . - pp 1042 - 1060[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2017031 RAB Revue Centre de documentation En réserve L003 Disponible Absolute orientation based on line coordinates / Qing H. Sheng in Photogrammetric record, vol 32 n° 157 (March - May 2017)
[article]
Titre : Absolute orientation based on line coordinates Type de document : Article/Communication Auteurs : Qing H. Sheng, Auteur ; Bing Zhang, Auteur Année de publication : 2017 Article en page(s) : pp 12 - 32 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] contour
[Termes IGN] coordonnées géographiques
[Termes IGN] espace image
[Termes IGN] espace objet
[Termes IGN] géoréférencement direct
[Termes IGN] orientation absolue
[Termes IGN] point d'appui
[Termes IGN] segment de droite
[Termes IGN] système de coordonnéesRésumé : (auteur) Absolute orientation based on points is a common method of precise georeferencing in photogrammetry. In images of urban areas, straight-line features such as buildings are prominent. A new absolute orientation approach dependent on line coordinates is proposed in this paper. An arbitrary spatial line can be described by its orientation vector and moment vector. Using the helical scaling displacement operator, the transformation of straight lines in model space and their corresponding control straight lines in object space can be achieved. Experimental results show that with eight control straight lines, the proposed approach is comparable to the precision of absolute orientation using four control points. Furthermore, the endpoints of corresponding line segments in the two spaces are not required to be conjugate points. Numéro de notice : A2017-195 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/phor.12178 En ligne : http://dx.doi.org/10.1111/phor.12178 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84869
in Photogrammetric record > vol 32 n° 157 (March - May 2017) . - pp 12 - 32[article]Refining geometry from depth sensors using IR shading images / Gyeongmin Choe in International journal of computer vision, vol 122 n° 1 (March 2017)
[article]
Titre : Refining geometry from depth sensors using IR shading images Type de document : Article/Communication Auteurs : Gyeongmin Choe, Auteur ; Jaesik Park, Auteur ; Yu-Wing Tai, Auteur ; In So Kweon, Auteur Année de publication : 2017 Article en page(s) : pp 1 – 16 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] albedo
[Termes IGN] bande infrarouge
[Termes IGN] décomposition d'image
[Termes IGN] géométrie affine
[Termes IGN] image optique
[Termes IGN] Kinect
[Termes IGN] maille triangulaire
[Termes IGN] ombreRésumé : (auteur) We propose a method to refine geometry of 3D meshes from a consumer level depth camera, e.g. Kinect, by exploiting shading cues captured from an infrared (IR) camera. A major benefit to using an IR camera instead of an RGB camera is that the IR images captured are narrow band images that filter out most undesired ambient light, which makes our system robust against natural indoor illumination. Moreover, for many natural objects with colorful textures in the visible spectrum, the subjects appear to have a uniform albedo in the IR spectrum. Based on our analyses on the IR projector light of the Kinect, we define a near light source IR shading model that describes the captured intensity as a function of surface normals, albedo, lighting direction, and distance between light source and surface points. To resolve the ambiguity in our model between the normals and distances, we utilize an initial 3D mesh from the Kinect fusion and multi-view information to reliably estimate surface details that were not captured and reconstructed by the Kinect fusion. Our approach directly operates on the mesh model for geometry refinement. We ran experiments on our algorithm for geometries captured by both the Kinect I and Kinect II, as the depth acquisition in Kinect I is based on a structured-light technique and that of the Kinect II is based on a time-of-flight technology. The effectiveness of our approach is demonstrated through several challenging real-world examples. We have also performed a user study to evaluate the quality of the mesh models before and after our refinements. Numéro de notice : A2017-174 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007%2Fs11263-016-0937-y En ligne : https://doi.org/10.1007/s11263-016-0937-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85921
in International journal of computer vision > vol 122 n° 1 (March 2017) . - pp 1 – 16[article]A spatial zoning approach to calibrate and validate urban growth models / Ali Kazemzadeh-Zow in International journal of geographical information science IJGIS, vol 31 n° 3-4 (March-April 2017)PermalinkUsing vector building maps to aid in generating seams for low-attitude aerial orthoimage mosaicking: Advantages in avoiding the crossing of buildings / Dongliang Wang in ISPRS Journal of photogrammetry and remote sensing, vol 125 (March 2017)PermalinkCaractérisation de la végétation de Rennes Métropole par relevé LiDAR en vue de sa modélisation / Clément Doceul (2017)PermalinkContinuously generalizing buildings to built-up areas by aggregating and growing / Dongliang Peng (2017)PermalinkEléments de géodésie et de la théorie des moindres carrés / Abdelmajid Ben Hadj Salem (2017)PermalinkPermalinkPermalinkExtracting building patterns with multilevel graph partition and building grouping / Shihong Du in ISPRS Journal of photogrammetry and remote sensing, vol 122 (December 2016)PermalinkmR-V: Line simplification through mnemonic rasterization / Emmanuel Stefanakis in Geomatica, vol 70 n° 4 (December 2016)PermalinkSymbolize map distortion with inscribed circles in polygons / Shipeng Sun in International journal of cartography, vol 2 n° 2 (December 2016)Permalink