Détail de l'auteur
Auteur Derek D. Lichti |
Documents disponibles écrits par cet auteur (22)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externes
Automated calibration of smartphone cameras for 3D reconstruction of mechanical pipes / Reza Maalek in Photogrammetric record, vol 36 n° 174 (June 2021)
[article]
Titre : Automated calibration of smartphone cameras for 3D reconstruction of mechanical pipes Type de document : Article/Communication Auteurs : Reza Maalek, Auteur ; Derek D. Lichti, Auteur Année de publication : 2021 Article en page(s) : pp 124 - 146 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] appariement de formes
[Termes IGN] auto-étalonnage
[Termes IGN] canalisation
[Termes IGN] compensation par faisceaux
[Termes IGN] ellipse
[Termes IGN] étalonnage d'instrument
[Termes IGN] reconstruction 3D
[Termes IGN] structure-from-motion
[Termes IGN] téléphone intelligent
[Termes IGN] triangulationRésumé : (auteur) This paper outlines a new framework for the calibration of optical instruments, in particular smartphone cameras, using highly redundant circular black-and-white target fields. New methods were introduced for (i) matching targets between images; (ii) adjusting the systematic eccentricity error of target centres; and (iii) iteratively improving the calibration solution through a free-network self-calibrating bundle adjustment. The proposed method effectively matched circular targets in 270 smartphone images, taken within a calibration laboratory, with robustness to type II errors (false negatives). The proposed eccentricity adjustment, which requires only camera projective matrices from two views, behaved comparably to available closed-form solutions, which require additional a priori object-space target information. Finally, specifically for the case of mobile devices, the calibration parameters obtained using the framework were found to be superior compared to in situ calibration for estimating the 3D reconstructed radius of a mechanical pipe (approximately 45% improvement on average). Numéro de notice : A2021-512 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/phor.12364 Date de publication en ligne : 06/06/2021 En ligne : https://doi.org/10.1111/phor.12364 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97929
in Photogrammetric record > vol 36 n° 174 (June 2021) . - pp 124 - 146[article]Geometric modelling and calibration of a spherical camera imaging system / Derek D. Lichti in Photogrammetric record, vol 35 n° 170 (June 2020)
[article]
Titre : Geometric modelling and calibration of a spherical camera imaging system Type de document : Article/Communication Auteurs : Derek D. Lichti, Auteur ; David Jarron, Auteur ; Wynand Tredoux, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 123 - 142 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] acquisition d'images
[Termes IGN] auto-étalonnage
[Termes IGN] caméra 3D
[Termes IGN] colinéarité
[Termes IGN] distorsion radiale
[Termes IGN] instrument de photogrammétrie
[Termes IGN] modélisation géométrique de prise de vue
[Termes IGN] orientation relative
[Termes IGN] reconstruction 3D
[Termes IGN] système de numérisation mobileRésumé : (auteur) The Ladybug5 is an integrated, multi‐camera system that features a near‐spherical field of view. It is commonly deployed on mobile mapping systems to collect imagery for 3D reality capture. This paper describes an approach for the geometric modelling and self‐calibration of this system. The collinearity equations of the pinhole camera model are augmented with five radial lens distortion terms to correct the severe barrel distortion. Weighted relative orientation stability constraints are added to the self‐calibrating bundle adjustment solution to enforce the angular and positional stability between the Ladybug5’s six cameras. Centimetre‐level 3D reconstruction accuracy can be achieved, with image‐space precision and object‐space accuracy improved by 92% and 93% , respectively, relative to a two‐term lens distortion model. Sub‐pixel interior orientation stability and millimetre‐level relative orientation stability were also demonstrated over a 10‐month period. Numéro de notice : A2020-401 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/phor.12315 Date de publication en ligne : 29/06/2020 En ligne : https://doi.org/10.1111/phor.12315 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95438
in Photogrammetric record > vol 35 n° 170 (June 2020) . - pp 123 - 142[article]Validation and verification procedures for defining legal 3D boundaries using terrestrial laser scanners / Sam Rondeel in Survey review, Vol 52 n°370 (January 2020)
[article]
Titre : Validation and verification procedures for defining legal 3D boundaries using terrestrial laser scanners Type de document : Article/Communication Auteurs : Sam Rondeel, Auteur ; Michael Barry, Auteur ; Derek D. Lichti, Auteur Année de publication : 2020 Article en page(s) : pp 69 - 75 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] délimitation de frontière
[Termes IGN] données localisées 3D
[Termes IGN] données TLS (télémétrie)
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] géomètre
[Termes IGN] instrument de mesure
[Termes IGN] semis de points
[Termes IGN] tachéomètre électronique
[Termes IGN] topographieRésumé : (auteur) A gap exists in law and practice with respect to calibrating terrestrial laser scanners (TLS) for legal boundary surveying. Laws, calibration infrastructure and calibration procedures have long existed for electronic distance measurement units used for boundary surveys, but laser scanners present new challenges. The aim of this paper is to present a practical, inexpensive procedure for validating laser scanner calibration and for verifying surface information extracted from terrestrial laser scanner data. The methodology verifies the TLS calibration parameters and extracted surfaces using total station measurements. The results indicate that total stations and TLS are complimentary tools and should both be used where complicated 3D boundaries exist. Numéro de notice : A2020-026 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2018.1518800 Date de publication en ligne : 08/09/2018 En ligne : https://doi.org/10.1080/00396265.2018.1518800 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94474
in Survey review > Vol 52 n°370 (January 2020) . - pp 69 - 75[article]Explanation for the seam line discontinuity in terrestrial laser scanner point clouds / Derek D. Lichti in ISPRS Journal of photogrammetry and remote sensing, vol 154 (August 2019)
[article]
Titre : Explanation for the seam line discontinuity in terrestrial laser scanner point clouds Type de document : Article/Communication Auteurs : Derek D. Lichti, Auteur ; Craig L. Glennie, Auteur ; Kaleel Al-Durgham, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 59 - 69 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] angle de visée
[Termes IGN] discontinuité
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestreRésumé : (Auteur) The so-called seam line discontinuity is a phenomenon that can be observed in point clouds captured with some panoramic terrestrial laser scanners. It is an angular discontinuity that is most apparent where the lower limit of the instrument’s angular field-of-view intersects the ground. It appears as step discontinuities at the start (0° horizontal direction) and end (180°) of scanning. To the authors’ best knowledge, its cause and its impact, if any, on point cloud accuracy have not yet been reported. This paper presents the results of a rigorous investigation into several hypothesized causes of this phenomenon: differences between the lower and upper elevation angle scanning limits; the presence of a vertical circle index error; and changes in levelling during scanning. New models for the angular observations have been developed and simulations were performed to independently study the impact of each hypothesized cause and to guide the analyses of real datasets. In order to scrutinize each of the hypothesized causes, experiments were conducted with seven real datasets captured with six different instruments: one hybrid-architecture scanner and five panoramic scanners, one of which was also operated as a hybrid instrument. This study concludes that the difference between the elevation angle scanning limits is the source of the seam line discontinuity phenomenon. Accuracy assessment experiments over real data captured in an indoor test facility demonstrate that the seam line discontinuity has no metric impact on the point clouds. Numéro de notice : A2019-264 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.05.012 Date de publication en ligne : 06/06/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.05.012 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93078
in ISPRS Journal of photogrammetry and remote sensing > vol 154 (August 2019) . - pp 59 - 69[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2019081 RAB Revue Centre de documentation En réserve L003 Disponible 081-2019083 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2019082 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt Digital preservation, social history, and the Quon Sang Lung Laundry building : a case study from Fort Macleod, Alberta, Canada / Peter Dawson in Applied geomatics, vol 10 n° 4 (December 2018)
[article]
Titre : Digital preservation, social history, and the Quon Sang Lung Laundry building : a case study from Fort Macleod, Alberta, Canada Type de document : Article/Communication Auteurs : Peter Dawson, Auteur ; Alireza Farrokhi, Auteur ; Allan Rowe, Auteur ; Farzan Baradaran, Auteur ; Derek D. Lichti, Auteur Année de publication : 2018 Article en page(s) : pp 361 - 375 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Alberta (Canada)
[Termes IGN] conservation du patrimoine
[Termes IGN] histoire
[Termes IGN] immigration
[Termes IGN] reconstruction 3D du bâti
[Termes IGN] semis de pointsRésumé : (Auteur) Social history focuses on understanding the everyday lives of ordinary people (Richardson 2011, Social history, local history, and historiography: collected essays). The ethnic minorities that made up immigrant communities in North American towns and cities during the late nineteenth and early twentieth centuries have been of particular interest to social historians (Tosh 2017, From the ‘cape of despair’ to the Cape of Good Hope: letters of the emigrant poor in early nineteenth-century England. Social History 42:480–500). However, language barriers and low rates of literacy often limit the number of first person accounts written by people who belonged to such communities. This paper explores how terrestrial laser scanning (TLS) and 3D reconstructive modeling of heritage buildings can provide new insights into the social history of Chinese immigrants in Alberta during the nineteenth and early twentieth centuries. These technologies were used to rapidly and accurately document the Quon Sang Lung Laundry shop in Fort Macleod, Alberta, prior to its scheduled demolition. The resulting digital data sets were used to construct detailed architectural plans of the building, as well as photorealistic 3D reconstructions of the shop, as it would have appeared at different points in history. The resulting point clouds were further explored to detect and extract evidence of the lived experiences of its occupants. For example, the conflicts and tensions surrounding Chinese laundries, and the discriminatory bylaws that resulted, may be subtly reflected in specific architectural details of the laundry shop, such as evidence for the presence of walls no longer standing. The ability to return to accurate digital models, over and over again, provides unique opportunities to construct social histories of buildings long after they are gone. Numéro de notice : A2018-591 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s12518-018-0232-4 Date de publication en ligne : 11/07/2018 En ligne : https://doi.org/10.1007/s12518-018-0232-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92515
in Applied geomatics > vol 10 n° 4 (December 2018) . - pp 361 - 375[article]The practical application of 3D vision in the field: Measuring reindeer (rangifer tarandus) antler growth velocities / Derek D. Lichti in Photogrammetric record, vol 31 n° 156 (December 2016 - February 2017)PermalinkA rigorous cylinder-based self-calibration approach for terrestrial laser scanners / Ting On Chan in ISPRS Journal of photogrammetry and remote sensing, vol 99 (January 2015)PermalinkStructural dynamic deflection measurement with range cameras / Xiaojuan Qi in Photogrammetric record, vol 29 n° 145 (March - May 2014)PermalinkMulti-feature based boresight self-calibration of a terrestrial mobile mapping system / Ting On Chan in ISPRS Journal of photogrammetry and remote sensing, vol 82 (August 2013)PermalinkInner constraints for planar features / Derek D. Lichti in Photogrammetric record, vol 28 n° 141 (March - May 2013)PermalinkRange camera self-calibration with scattering compensation / Derek D. Lichti in ISPRS Journal of photogrammetry and remote sensing, vol 74 (Novembrer 2012)PermalinkAn integrated bundle adjustment approach to range camera geometric self-calibration / Derek D. Lichti in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 4 (July - August 2010)PermalinkTerrestrial laser scanner self-calibration: correlation sources and their mitigation / Derek D. Lichti in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 1 (January - February 2010)PermalinkA method to test differences between additional parameter sets with a case study in terrestrial laser scanner self-calibration stability analysis / Derek D. Lichti in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 2 (March - April 2008)PermalinkA method for automated registration of unorganised point clouds / K. Bae in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 1 (January - February 2008)Permalink