Centre de documentation
scientifique

Dépouillements

On improving navigation accuracy of GPS/INS systems / Dorota A. Grejner-Brzezinska in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 4 (April 2005)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 4 (April 2005) Titre : On improving navigation accuracy of GPS/INS systems Type de document : Article/Communication Auteurs : Dorota A. Grejner-Brzezinska, Auteur ; Charles K. Toth, Auteur ; Y. Yi, Auteur Année de publication : 2005 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale [Termes IGN] capteur à balayage [Termes IGN] capteur imageur [Termes IGN] centrale inertielle [Termes IGN] élément d'orientation externe [Termes IGN] filtrage du bruit [Termes IGN] géoréférencement direct [Termes IGN] GPS-INS [Termes IGN] modèle d'erreur [Termes IGN] modèle stochastique [Termes IGN] orientation du capteur [Termes IGN] pesanteur terrestre [Termes IGN] point d'appui [Termes IGN] positionnement par GPS [Termes IGN] précision de localisation [Termes IGN] système de numérisation mobile Résumé : (Auteur) Direct georeferencing, also referred to as direct platform orientation (DPO), is defined as direct measurement of the imaging sensor external orientation parameters (EOP), using positioning and orientation sensors, such as the Global Positioning System (GPS) and Inertial Navigation System (INS) or Inertial Measurement Unit (Imu). Imaging sensors, most frequently supported by the Dpo technique, are digital cameras, lidar systems, multi-spectral or hyper-spectral scanners, or interferometric synthetic aperture radar (INSAR). While for scanning sensors, the use of Dpo is compulsory, frame digital cameras can also directly benefit from this modern technique of sensor orientation. With direct sensor orientation, the requirement for ground control, tie-point matching and aerotriangulation (AT) is significantly reduced, or even entirely eliminated, resulting in shorter times of data acquisition and processing, and streamlined and highly automated data workflow and quality control. Most of the time, the requirement for ground control points is limited to periodic system calibrations and quality control check. Direct georeferencing is considered a fundamental technology of conventional mobile mapping systems (MMS). Despite significant progress in GSP/INS-based direct georeferencing technology in the last decade, there is still room for improvement in terms of better accuracy and better tolerance to GPS outages. This paper is focused on three error modeling and compensation techniques that could potentially improve GPS/INS system's performance on both land-based and airborne platforms : (1) extended gravity compensation, (2) IMU signal de-noising, and (3) stochastic modeling of IMU errors. Numéro de notice : A2005-158 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.14358/PERS.71.4.377 En ligne : https://doi.org/10.14358/PERS.71.4.377 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27296 [article]

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)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 4 (April 2005) . - pp 405 - 414 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'intérêt Résumé : (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 [article]

Updating a digital geographic database using Vehicle-borne Laser scanners and line cameras / H. Zhao in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 4 (April 2005)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 4 (April 2005) . - pp 415 - 424 Titre : Updating a digital geographic database using Vehicle-borne Laser scanners and line cameras Type de document : Article/Communication Auteurs : H. Zhao, Auteur ; Ryosuke Shibasaki, Auteur Année de publication : 2005 Article en page(s) : pp 415 - 424 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique [Termes IGN] 1:2.000 [Termes IGN] base de données localisées [Termes IGN] caméra numérique [Termes IGN] cartographie 3D [Termes IGN] chambre DTC [Termes IGN] données multitemporelles [Termes IGN] fusion de données [Termes IGN] géoréférencement direct [Termes IGN] GPS-INS [Termes IGN] instrument embarqué [Termes IGN] milieu urbain [Termes IGN] mise à jour de base de données [Termes IGN] signalisation routière [Termes IGN] système de numérisation mobile [Termes IGN] télémètre laser terrestre [Termes IGN] télémétrie laser terrestre [Termes IGN] texture d'image [Termes IGN] Tokyo (Japon) Résumé : (Auteur) The Vehicle-borne Laser Measurement System (VLMS) is a mobile mapping system where three single-row laser range scanners, six line CCD cameras, and a GPS/INS-based navigation unit are mounted on a van to measure object geometry and texture along a street. This paper contributes to a method of fusing the data output of VLMS with existing geographic data sources where the focus is on the rectification of the vehicle's motion data derived from GPS/INS, which may be quite erroneous in an urban area. An algorithm is developed to correct the four variables of the vehicle's motion data, i.e., x, y, and z coordinates of the vehicle position and yaw angle of orientation by registering the laser points of the VLMS with an existing data source, e.g., a DSM. The algorithm was examined using the VLMS data that were taken in the Ginza District, Tokyo. By manually assigning 18 sets of tie-points, the vehicle's motion data were corrected automatically and efficiently, such that the laser points of VLMS were matched to a DSM. In data fusion, a set of objects, which contained commercial signboards, traffic signs and signals, road boundaries, and road lights were extracted from the corrected VLMS data using an interface described in a previous paper. They were integrated with a 1:2500 3D map that consists of only building frames. In addition, line images from the VLMS were projected onto the building facades of the 3D Map, and textures were generated automatically. Copyright ASPRS Numéro de notice : A2005-160 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.71.4.415 En ligne : https://doi.org/10.14358/PERS.71.4.415 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27298 [article]

Integration of mobile GIS and wireless technology for coastal management and decision-making / X. Niu in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 4 (April 2005)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 4 (April 2005) . - pp 453 - 459 Titre : Integration of mobile GIS and wireless technology for coastal management and decision-making Type de document : Article/Communication Auteurs : X. Niu, Auteur ; R. Ma, Auteur ; T. Ali, Auteur ; R. Li, Auteur Année de publication : 2005 Article en page(s) : pp 453 - 459 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG [Termes IGN] aménagement du littoral [Termes IGN] architecture de système [Termes IGN] érosion côtière [Termes IGN] internet [Termes IGN] outil d'aide à la décision [Termes IGN] positionnement par GPS [Termes IGN] SIG nomade [Termes IGN] surveillance géologique [Termes IGN] système d'information géographique [Termes IGN] télécommunication sans fil Résumé : (Auteur) Geographic Information Systems (Gis) have become a crucial support tool for governmental decision makers at many levels. Intemet-based Gis applications provide unique services for the presentation of spatial data and mapping products to a broad range of audiences. Furthermore, compact and portable mapping devices provide new opportunities for the expansion of Internet-based Gis applications. In this paper, we present results of the research and development of a web-based, mobile, spatial system for coastal management, and decision-making that integrates these technologies. The developed system consists of an on-site mobile spatial subsystem, a web-based shoreline erosion awareness subsystem, and a coastal structures permit subsystem. The system is designed and developed for applications in the Lake Erie area and has the potential to be adapted and applied in other coastal areas. Numéro de notice : A2005-161 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.14358/PERS.71.4.453 En ligne : https://doi.org/10.14358/PERS.71.4.453 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27299 [article]

Hierarchical recovery of digital terrain models from single and multiple return lidar data / Y. Hu in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 4 (April 2005)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 71 n° 4 (April 2005) . - pp 425 - 433 Titre : Hierarchical recovery of digital terrain models from single and multiple return lidar data Type de document : Article/Communication Auteurs : Y. Hu, Auteur ; V. Tao, Auteur Année de publication : 2005 Article en page(s) : pp 425 - 433 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes IGN] approche hiérarchique [Termes IGN] classification par seuillage sur la limite la plus proche [Termes IGN] convolution (signal) [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] interpolation [Termes IGN] lasergrammétrie [Termes IGN] modèle numérique de terrain Résumé : (Auteur) A hierarchical terrain recovery approach for generating digital terrain models (DTM) from single and multiple returns lidar data is presented in this paper. The algorithm can intelligently discriminate between terrain and non-terrain points by using adaptive and robust filtering and interpolation techniques. It processes the image pyramid, bottom-up and top-down, to estimate high-quality terrain surfaces from lidar data with varying point densities and scene complexities. Using road and vegetation information, the algorithm is able to adaptively adjust thresholds to be suited to process changing contents in a large scene. The algorithms have been tested extensively using multiple medium - and high - resolution lidar datasets. The worst-case error is below 25 cm Linear Error (LE) 90 comparing the derived DTMs and the raw range images on bare surfaces when testing several lidar datasets. Copyright ASPRS Numéro de notice : A2005-589 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : https://doi.org/10.14358/PERS.71.4.425 En ligne : https://doi.org/10.14358/PERS.71.4.425 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27724 [article]