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Georeferencing with self-calibration for airborne full-waveform Lidar data using digital elevation model / Qinghua Li in Photogrammetric Engineering & Remote Sensing, PERS, vol 87 n° 1 (January 2021)
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Titre : Georeferencing with self-calibration for airborne full-waveform Lidar data using digital elevation model Type de document : Article/Communication Auteurs : Qinghua Li, Auteur ; Jie Shan, Auteur Année de publication : 2021 Article en page(s) : pp 43 - 52 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes descripteurs IGN] autoétalonnage
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] étalonnage de capteur (imagerie)
[Termes descripteurs IGN] forme d'onde pleine
[Termes descripteurs IGN] géoréférencement
[Termes descripteurs IGN] modèle géométrique de prise de vue
[Termes descripteurs IGN] modèle numérique de surface
[Termes descripteurs IGN] optimisation (mathématiques)
[Termes descripteurs IGN] point d'appui
[Termes descripteurs IGN] synchronisationRésumé : (Auteur) Precise georeferencing of airborne full-waveform lidar is a complex process. On one hand, no ground control points are visible due to heavy canopy. While on the other hand, precise georeferencing relies on ground control. As an alternative, we propose to use an available digital elevation model (DEM ) as control. The mathematical framework minimizes the difference between the lidar DEM and the reference DEM. Our solution consists of two steps: initial optimization to find reliable ground points through iterative filtering and georeferencing, and fine optimization to achieve precise georeferencing and lidar system calibration. Through this approach, the wave-form-derived DEM can best fit the reference DEM, with a mean of 0.937 m and standard deviation of 0.792 m, while the time-synchronization offset and boresight angles are simultaneously determined, i.e., self-calibrated. This development provides a novel georeferencing approach with self-calibration for lidar data without using conventional ground control points. Numéro de notice : A2021-056 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14358/PERS.87.1.43 date de publication en ligne : 01/01/2021 En ligne : https://doi.org/10.14358/PERS.87.1.43 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96766
in Photogrammetric Engineering & Remote Sensing, PERS > vol 87 n° 1 (January 2021) . - pp 43 - 52[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 105-2021011 SL Revue Centre de documentation Revues en salle Disponible Geometric modelling and calibration of a spherical camera imaging system / Derek D. Lichti in Photogrammetric record, vol 35 n° 170 (June 2020)
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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 descripteurs IGN] acquisition d'images
[Termes descripteurs IGN] autoétalonnage
[Termes descripteurs IGN] chambre 3D
[Termes descripteurs IGN] colinéarité
[Termes descripteurs IGN] distorsion radiale
[Termes descripteurs IGN] instrument de photogrammétrie
[Termes descripteurs IGN] modélisation géométrique de prise de vue
[Termes descripteurs IGN] orientation relative
[Termes descripteurs IGN] reconstruction 3D
[Termes descripteurs 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]Method for real-time self-calibrating GLONASS code inter-frequency bias and improvements on single point positioning / Liang Chen in GPS solutions, vol 22 n° 4 (October 2018)
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Titre : Method for real-time self-calibrating GLONASS code inter-frequency bias and improvements on single point positioning Type de document : Article/Communication Auteurs : Liang Chen, Auteur ; Min Li, Auteur ; Zhigang Hu, Auteur ; et al., Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] autoétalonnage
[Termes descripteurs IGN] données GLONASS
[Termes descripteurs IGN] données GPS
[Termes descripteurs IGN] erreur systématique
[Termes descripteurs IGN] positionnement ponctuel précis
[Termes descripteurs IGN] temps réelMots-clés libres : code inter-frequency bias (cIFB) Résumé : (Auteur) Utilization of frequency-division multiple access (FDMA) leads to GLONASS pseudorange and carrier phase observations suffering from variable levels inter-frequency bias (IFB). The bias related with carrier phase can be absorbed by ambiguities. However, the unequal code inter-frequency bias (cIFB) will degrade the accuracy of pseudorange observations, which will affect positioning accuracy and convergence of precise point positioning (PPP) when including GLONASS satellites. Based on observations made on un-differenced (UD) ionospheric-free combinations, GLONASS cIFB parameters are estimated as a constant to achieve GLONASS cIFB real-time self-calibration on a single station. A total of 23 stations, with different manufacturing backgrounds, are used to analyze the characteristics of GLONASS cIFB and its relationship with variable receiver hardware. The results show that there is an obvious common trend in cIFBs estimated using broadcast ephemeris for all of the different manufacturers, and there are unequal GLONASS inter-satellite cIFB that match brand manufacture. In addition, a particularly good consistency is found between self-calibrated receiver-dependent GLONASS cIFB and the IFB products of the German Research Centre for Geosciences (GFZ). Via a comparative experiment, it is also found that the algorithm of cIFB real-time self-calibration not only corrects receiver-dependent cIFB, but can moreover eliminate satellite-dependent cIFB, providing more stable results and further improving global navigation satellite system (GNSS) point positioning accuracy. The root mean square (RMS) improvements of single GLONASS standard point positioning (SPP) reach up to 54.18 and 53.80% in horizontal and vertical direction, respectively. The study’s GLONASS cIFB self-estimation can realize good self-consistency between cIFB and stations, working to further promote convergence efficiency relative to GPS + GLONASS PPP. An average improvement percentage of 19.03% is observed, realizing a near-consistent accuracy with GPS + GLONASS fusion PPP. Numéro de notice : A2018-378 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-018-0774-2 date de publication en ligne : 17/08/2018 En ligne : https://doi.org/10.1007/s10291-018-0774-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90782
in GPS solutions > vol 22 n° 4 (October 2018)[article]Self-calibration of omnidirectional multi-cameras including synchronization and rolling shutter / Thanh-Tin Nguyen in Computer Vision and image understanding, vol 162 (September 2017)
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Titre : Self-calibration of omnidirectional multi-cameras including synchronization and rolling shutter Type de document : Article/Communication Auteurs : Thanh-Tin Nguyen, Auteur ; Maxime Lhuillier, Auteur Année de publication : 2017 Article en page(s) : pp 166 - 184 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes descripteurs IGN] autoétalonnage
[Termes descripteurs IGN] compensation par faisceaux
[Termes descripteurs IGN] image vidéo
[Termes descripteurs IGN] séquence d'images
[Termes descripteurs IGN] structure-from-motion
[Termes descripteurs IGN] synchronisationRésumé : (auteur) 360° and spherical cameras become popular and are convenient for applications like immersive videos. They are often built by fixing together several fisheye cameras pointing in different directions. However their complete self-calibration is not easy since the consumer fisheyes are rolling shutter cameras which can be unsynchronized. Our approach does not require a calibration pattern. First the multi-camera model is initialized thanks to assumptions that are suitable to an omnidirectional camera without a privileged direction: the cameras have the same setting and are roughly equiangular. Second a frame-accurate synchronization is estimated from the instantaneous angular velocities of each camera provided by monocular structure-from-motion. Third both inter-camera poses and intrinsic parameters are refined using multi-camera structure-from-motion and bundle adjustment. Last we introduce a bundle adjustment that estimates not only the usual parameters but also a sub-frame-accurate synchronization and the rolling shutter. We experiment using videos taken by consumer cameras mounted on a helmet and moving along trajectories of several hundreds of meters or kilometers, and compare our results to ground truth. Numéro de notice : A2017-562 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.cviu.2017.08.010 En ligne : https://doi.org/10.1016/j.cviu.2017.08.010 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86643
in Computer Vision and image understanding > vol 162 (September 2017) . - pp 166 - 184[article]Camera self-calibration with lens distortion from a single image / Dan Liu in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 5 (May 2016)
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Titre : Camera self-calibration with lens distortion from a single image Type de document : Article/Communication Auteurs : Dan Liu, Auteur ; Xuejun Liu, Auteur ; Meizhen Wang, Auteur Année de publication : 2016 Article en page(s) : pp 325 - 334 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes descripteurs IGN] autoétalonnage
[Termes descripteurs IGN] contrainte géométrique
[Termes descripteurs IGN] étalonnage de capteur (imagerie)
[Termes descripteurs IGN] photogrammétrie terrestreRésumé : (Auteur) This paper presents an effective approach for self-calibration with lens distortion using a single image combined with geometric constraints including vanishing points and ellipses. To improve the accuracy of self-calibration, radial distortion and distortion center are included in the calibration procedure. First, assuming image center as the symmetric center, the first radial distortion coefficient and vanishing points are simultaneously optimized from line segments in the image. Second, by utilizing the optimized vanishing points and extracted ellipse, principal distance and principal point are estimated. Last, distortion center is set as the current calculated principal point, and the above steps are then repeated until the principal point reaches a stable solution. Extensive quantitative and qualitative studies of the approach are performed. The experiments pertaining to simulated and real images demonstrate that the approach is effective and suitable and that the approach obtains satisfactory results. Numéro de notice : A2016-409 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article En ligne : http://dx.doi.org/10.14358/PERS.82.5.325 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81274
in Photogrammetric Engineering & Remote Sensing, PERS > vol 82 n° 5 (May 2016) . - pp 325 - 334[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 105-2016051 SL Revue Centre de documentation Revues en salle Disponible Improved area-based deformation analysis of a radio telescope’s main reflector based on terrestrial laser scanning / Christoph Holst in Journal of applied geodesy, vol 9 n° 1 (March 2015)
PermalinkIn-flight photogrammetric camera calibration and validation via complementary lidar / A.S. Gneeniss in ISPRS Journal of photogrammetry and remote sensing, vol 100 (February 2015)
PermalinkMétrologie par photogrammétrie aéroportée légère : application au suivi d'évolution de digues / Vincent Tournadre (2015)
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)
PermalinkGeometric analysis and self-calibration of ADS40 imagery / Sara Gonzalez in Photogrammetric record, vol 28 n° 142 (June - August 2013)
PermalinkAutomatic camera calibration in close range photogrammetry / Clive Simpson Fraser in Photogrammetric Engineering & Remote Sensing, PERS, vol 79 n° 4 (April 2013)
PermalinkAccuracy assessment of commercial self-calibrating bundle adjustment routines applied to archival aerial photography / Manuel Angel Aguilar in Photogrammetric record, vol 28 n° 141 (March - May 2013)
PermalinkCorrelation analysis of camera self-calibration in close range photogrammetry / Rongfu Tang in Photogrammetric record, vol 28 n° 141 (March - May 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)
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