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Auteur Jack C.P. Cheng |
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Development of a mixed pixel filter for improved dimension estimation using AMCW laser scanner / Qiang Wang in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)
[article]
Titre : Development of a mixed pixel filter for improved dimension estimation using AMCW laser scanner Type de document : Article/Communication Auteurs : Qiang Wang, Auteur ; Hoon Sohn, Auteur ; Jack C.P. Cheng, Auteur Année de publication : 2016 Article en page(s) : pp 246 - 258 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] classification pixellaire
[Termes IGN] données localisées 3D
[Termes IGN] filtre numérique
[Termes IGN] métrologie dimensionelle
[Termes IGN] précision des mesuresRésumé : (Auteur) Accurate dimension estimation is desired in many fields, but the traditional dimension estimation methods are time-consuming and labor-intensive. In the recent decades, 3D laser scanners have become popular for dimension estimation due to their high measurement speed and accuracy. Nonetheless, scan data obtained by amplitude-modulated continuous-wave (AMCW) laser scanners suffer from erroneous data called mixed pixels, which can influence the accuracy of dimension estimation. This study develops a mixed pixel filter for improved dimension estimation using AMCW laser scanners. The distance measurement of mixed pixels is firstly formulated based on the working principle of laser scanners. Then, a mixed pixel filter that can minimize the classification errors between valid points and mixed pixels is developed. Validation experiments were conducted to verify the formulation of the distance measurement of mixed pixels and to examine the performance of the proposed mixed pixel filter. Experimental results show that, for a specimen with dimensions of 840 mm × 300 mm, the overall errors of the dimensions estimated after applying the proposed filter are 1.9 mm and 1.0 mm for two different scanning resolutions, respectively. These errors are much smaller than the errors (4.8 mm and 3.5 mm) obtained by the scanner’s built-in filter. Numéro de notice : A2016-784 Affiliation des auteurs : non IGN Autre URL associée : Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.06.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2016.06.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82497
in ISPRS Journal of photogrammetry and remote sensing > vol 119 (September 2016) . - pp 246 - 258[article]Automatic transformation of different levels of detail in 3D GIS city models in CityGML / Yichuan Deng in International journal of 3-D information modeling, vol 4 n° 3 (July - September 2015)
[article]
Titre : Automatic transformation of different levels of detail in 3D GIS city models in CityGML Type de document : Article/Communication Auteurs : Yichuan Deng, Auteur ; Jack C.P. Cheng, Auteur Année de publication : 2015 Article en page(s) : pp 1 - 21 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] carte d'intérieur
[Termes IGN] CityGML
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] façade
[Termes IGN] niveau de détail
[Termes IGN] SIG 3D
[Termes IGN] visualisation 3DRésumé : (Auteur) 3D Geographic Information System (GIS) models are increasingly used for planning and analyses on a city level. Defining 3D GIS city models in different levels of detail (LoD) is often needed to browse and handle large models more efficiently. In this paper, a methodology framework for automatic transformation of different LoDs in CityGML is presented and illustrated. A new exterior shell extraction algorithm was developed from the Ray Tracing algorithm for classifying building surfaces as interior or exterior. A transformation framework among each LoD was developed based on the new exterior shell extraction algorithm. The transformation framework also includes an additional LoD called LoD3.5 that the authors proposed in this paper. The new LoD can satisfy the needs of applications which require information about interior rooms while maintaining a small data storage. The results show that the new exterior shell extraction algorithm can help achieve an automatic derivation of LoDs in CityGML. Numéro de notice : A2016-563 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.4018/ij3dim.2015070101 En ligne : http://doi.org/10.4018/ij3dim.2015070101 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81697
in International journal of 3-D information modeling > vol 4 n° 3 (July - September 2015) . - pp 1 - 21[article]Réservation
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