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W. Schindler, Alexander. « Reflections on Photogrammetry ». Membrana Journal of Photography, Vol. 3, no. 1 (2018) : 34–41. http://dx.doi.org/10.47659/m4.034.art.
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This article presents an overview of the history, principles, and current developments in the media technological field of photogrammetry. By chronicling the isomorphic shift taking place in image capturing, we seek to show that photogrammetry has led the way forward in seeing technical images not only as two dimensional projections, but as three-dimensional model-based images. In the mid-nineteenth century, photogrammetry was first used for the documentation of architectural objects and it later became a standard technique in aerial photography. Although its fields of application have become more extensive, photogrammetry’s basic principle hasn’t fundamentally changed: it is still defined as the three- dimensional geometric reconstruction of two-dimensional photographs through the measuring of reference points. With digital technological standards and advances in camera technology, photogrammetric imaging nowadays is intensively used for object recognition in machine vision and robotics. Beside this, photogrammetry is also opening new possibilities for documentation in the fields of investigative arts, this being explored with a discussion on the “Ground Truth” project from Forensic Architecture. Keywords: investigative art, machine vision, object recognition, photogrammetry, photography
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Gruen, Armin W., et Horst A. Beyer. « REAL-TIME PHOTOGRAMMETRY AT THE DIGITAL PHOTOGRAMMETRIC STATION (DIPS) OF ETH ZURICH ». Canadian Surveyor 41, no 2 (juin 1987) : 181–99. http://dx.doi.org/10.1139/tcs-1987-0014.
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Real-time photogrammetry (RTP) is a non-contact three-dimensional measurement technique with a response time of one video cycle. As part of a research and development program for digital and real-time photogrammetry, the Institute of Geodesy and Photogrammety at the Swiss Federal Institute of Technology, Zurich, Switzerland, has established the Digital Photogrammetric Station (DIPS). The hardware and software of this development system is explained. Hardware aspects of solid-state cameras relevant to camera calibration for RTP are discussed. An off-line bundle adjustment program with additional parameters has been installed. An initial calibration and point positioning test using this program and existing image processing algorithms has been performed. The processing steps and results are analyzed. Accuracies, as computed from object space check points, in planimetry of 1:5000 or 0.09 pixel pitch, in depth of 0.08%c of object distance, have been achieved.
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Teo, T. A. « 3D DEFORMATION MEASUREMENT OF CONCRETE WALL USING CLOSE-RANGE PHOTOGRAMMETRY ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2020 (14 août 2020) : 1175–79. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2020-1175-2020.
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Abstract. Due to the development of digital image processing, digital photogrammetry is becoming an interesting research area in the field of structural monitoring in civil engineering. This study presents a photogrammetric measurement technique for concrete wall deformation monitoring in the destructive experiment. The non-contact photogrammetric measurement technique which provides surface deformation, is more flexible than the contacted single-point measurement technique (e.g., linear variable displacement transducers, LVDT). The major steps of the proposed scheme include (1) camera calibration, (2) orientation modeling, (3) 3D dense matching, and (4) filtering and interpolation for surface deformation. This experiment used two non-metric digital cameras to measure the deformation of a concrete wall in destructive experiment. The validation compared the image-derived and ranger-derived displacements during the experiment with mean error and standard errors of 32 epochs were −0.02mm and 0.81mm, respectively. The correlation between image-derived displacement and LVDT-derived displacement was 0.9803. The advantage of photogrammetry is to derive surface deformation which covered the whole wall during the experiment. In summary, this study demonstrated that photogrammetry is a useful measurement technique for concrete wall destructive experiment.
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Galantucci, L. M., R. Ferrandes et G. Percoco. « Digital Photogrammetry for Facial Recognition ». Journal of Computing and Information Science in Engineering 6, no 4 (30 mai 2006) : 390–96. http://dx.doi.org/10.1115/1.2356499.
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In this paper, the authors present a biometric low-cost 3D acquisition system, based on a digital photogrammetry technique. The aim of the work is to analyze the suitability of this system for facial recognition purposes. The facial data of a set of 20 people were acquired with the photogrammetric system developed by the authors, and different CAD 3D models were reconstructed for each person. The results are quantified by aligning the models and calculating mean distances and standard deviations between them using two different methods. The former considers the entire face; the latter is based on a few fiducial points of the face.
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Nishiyama, Satoshi, Nao Minakata, Teruyuki Kikuchi et Takao Yano. « Improved digital photogrammetry technique for crack monitoring ». Advanced Engineering Informatics 29, no 4 (octobre 2015) : 851–58. http://dx.doi.org/10.1016/j.aei.2015.05.005.
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Elhalawani, Mariem A., Zaki M. Zeidan et Ashraf A. A. Beshr. « IMPLEMENTATION OF CLOSE RANGE PHOTOGRAMMETRY USING MODERN NON-METRIC DIGITAL CAMERAS FOR ARCHITECTURAL DOCUMENTATION ». Geodesy and cartography 47, no 1 (26 avril 2021) : 45–53. http://dx.doi.org/10.3846/gac.2021.11269.
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The development of applied geodetic techniques for mapping and documentation of historical structures, buildings and sites is an important and vital purpose for contribution of any recording of cultural heritage for any country such as Egypt. This is done to preserve and restore any valuable architectural or other cultural monument, as a support to architectural, archaeological and other art-historical research throughout the ages. The purpose of this paper is to use close range photogrammetry technique (CRP) to reconstruct 3D model of architectural and historical mosque facade and comparing the accuracy of using digital commercial non-metric cameras with different resolutions and metric camera with flatbed scanner and photogrammetric scanner for architectural building documentation. El-Nasr Mosque façade in Mansoura city, Egypt was chosen as a case study in this paper. At first, twenty five points were selected at mosque façade at different elevations and distributed at different façade surfaces and observed using total station. Some of these points were selected as control points and the others were selected as check points to validate the results. Effect of control point’s number on image processing and analysis is also studied. Three cameras positions were selected for imaging to get the full details of mosque façade. Close range Digital Workstation (CDW) program was used for processing and analysis of multiple images. The results are indicated that close range photogrammetry using metric camera with photogrammetry scanner instead of flatbed scanner in technique is accurate enough to be beneficial in 3D architectural building documentation. Digital cameras with CRP technique give up different accuracy that depends mainly on the resolution of cameras and camera specifications.
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Alsadik, B., M. Gerke et G. Vosselman. « Visibility analysis of point cloud in close range photogrammetry ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences II-5 (28 mai 2014) : 9–16. http://dx.doi.org/10.5194/isprsannals-ii-5-9-2014.
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The ongoing development of advanced techniques in photogrammetry, computer vision (CV), robotics and laser scanning to efficiently acquire three dimensional geometric data offer new possibilities for many applications. The output of these techniques in the digital form is often a sparse or dense point cloud describing the 3D shape of an object. Viewing these point clouds in a computerized digital environment holds a difficulty in displaying the visible points of the object from a given viewpoint rather than the hidden points. This visibility problem is a major computer graphics topic and has been solved previously by using different mathematical techniques. However, to our knowledge, there is no study of presenting the different visibility analysis methods of point clouds from a photogrammetric viewpoint. The visibility approaches, which are surface based or voxel based, and the hidden point removal (HPR) will be presented. Three different problems in close range photogrammetry are presented: camera network design, guidance with synthetic images and the gap detection in a point cloud. The latter one introduces also a new concept of gap classification. Every problem utilizes a different visibility technique to show the valuable effect of visibility analysis on the final solution.
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EL-ASHMAWY, Khalid L. A. « USING SMART PHONES FOR DEFORMATIONS MEASUREMENTS OF STRUCTURES ». Geodesy and cartography 43, no 2 (25 juin 2017) : 66–72. http://dx.doi.org/10.3846/20296991.2017.1330770.
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The present work tests the suitability of using the digital cameras of smart phones for close range photogrammetry applications. For this purpose two cameras of smart phones Lumia 535 and Lumia 950 XL were used. The resolutions of the two cameras are 5 and 20 Mpixels respectively. The tests consist of (a) self calibration of the two cameras, (b) the implementation of close-range photogrammetry using the cameras of the two smart phones, theodolite intersection with LST method, and linear variable displacement transducers (LVDTs) for the measurement of vertical deflections, and (c) accuracy of photogrammetric determination of object space coordinates. The results of using Lumia 950 XL are much better than using Lumia 535 and are better or comparable to the results of theodolite intersection with least squares technique (LST). Finally, it can be stated that the digital cameras of smart phones are suitable for close range photogrammetry applications according to accuracy, costs and flexibility.
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Jo, Y. H., et J. Y. Kim. « THREE-DIMENSIONAL DIGITAL DOCUMENTATION OF HERITAGE SITES USING TERRESTRIAL LASER SCANNING AND UNMANNED AERIAL VEHICLE PHOTOGRAMMETRY ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W5 (18 août 2017) : 395–98. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w5-395-2017.
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Three-dimensional digital documentation is an important technique for the maintenance and monitoring of cultural heritage sites. This study focuses on the three-dimensional digital documentation of the Magoksa Temple, Republic of Korea, using a combination of terrestrial laser scanning and unmanned aerial vehicle (UAV) photogrammetry. Terrestrial laser scanning mostly acquired the vertical geometry of the buildings. In addition, the digital orthoimage produced by UAV photogrammetry had higher horizontal data acquisition rate than that produced by terrestrial laser scanning. Thus, the scanning and UAV photogrammetry were merged by matching 20 corresponding points and an absolute coordinate system was established using seven ground control points. The final, complete threedimensional shape had perfect horizontal and vertical geometries. This study demonstrates the potential of integrating terrestrial laser scanning and UAV photogrammetry for three-dimensional digital documentation. This new technique is expected to contribute to the three-dimensional digital documentation and spatial analysis of cultural heritage sites.
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Shahbazi, M. « Hybrid 3D Dynamic Measurement by Particle Swarm Optimization and Photogrammetric Tracking ». Measurement Science Review 13, no 6 (1 décembre 2013) : 298–304. http://dx.doi.org/10.2478/msr-2013-0044.
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Abstract High-accuracy motion modeling in three dimensions via digital images has been increasingly the matter of interest in photogrammetry and computer vision communities. Although accurate sub-pixel image registration techniques are the key elements of measurement, they still demand enhanced intelligence, autonomy, and robustness. In this paper, a new correlationbased technique of stereovision is proposed to perform inter-frame feature tracking, inter-camera image registration, and to measure the 3D state vector of features simultaneously. The developed algorithm is founded on population-based intelligence (particle swarm optimization) and photogrammetric modeling. The proposed technique is mainly aimed at reducing the computational complexities of non-linear optimization methods of digital image registration for deformation measurement, and passing through 2D image correlation to 3D motion modeling. The preliminary results have illustrated the feasibility of this technique to detect and measure sub-millimeter deformations by performing accurate, sub-pixel image registration.
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Kumar, Umesh. « Replacement of Professional Photogrammetric Workstations with Low Cost or Free of Charge Photogrammetric Software and Services for Image Triangulation and Image Matching ». Journal on Geoinformatics, Nepal 12 (31 octobre 2013) : 42–48. http://dx.doi.org/10.3126/njg.v12i0.9072.
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In the modern context of digital technology in the field of surveying and mapping, the technique of digital photogrammetry plays crucial role in all steps of mapping. There are some very expensive as well as low cost and free softwares are available in the market for professional photogrammetric work stations. The image triangulation and image matching is one of the very important steps of photogrammetry for which LPS as a commercial software is available in market. There are some low cost and free software as 123D Catch and Patch Boased Multi View Stereo Softwear (PMVS) also available. So, this paper mainly deals with the accuracy as well as the performance of those software for aerial triangulation and image matching for airborne image data to substitute commercial software for photogrammetric workstations. The accuracy assessment of image orientation, points cloud as well as DSM generated from those points cloud are also performed and compared with all products of LPS as commercial software. Nepalese Journal on Geoinformatics -12, 2070 (2013AD): 42-48
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Waite, Jason N., Wendy J. Schrader, Jo-Ann E. Mellish et Markus Horning. « Three-dimensional photogrammetry as a tool for estimating morphometrics and body mass of Steller sea lions (Eumetopias jubatus) ». Canadian Journal of Fisheries and Aquatic Sciences 64, no 2 (1 février 2007) : 296–303. http://dx.doi.org/10.1139/f07-014.
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A technique was developed to estimate morphometrics and body mass of Steller sea lions (Eumetopias jubatus) using three-dimensional (3D) photogrammetry. 3D photogrammetry reduces many of the problems associated with camera and body position encountered with two-dimensional photogrammetric techniques, allowing body mass estimation of free-ranging, active sea lions, without sedation, heavy weighing equipment, and disturbance. 3D computer wireframes of 53 Steller sea lions of various age classes were generated from multiple time-synchronous digital photos and used to estimate length, girth, and volume. Average estimates of standard length and axillary girth were within ±2.5% and ±4.0% of physically measured dimensions, respectively. Average estimates of standard length and axillary girth using only wireframes based on ideal body postures were within ±1.7% and ±3.1% of physically measured dimensions, respectively. Regressions of physically measured mass on photogrammetrically estimated body volume yielded a predictive model. Body mass estimates using this model were on average within 9.0% (95% confidence interval = ±1.7%) of the physically measured mass. This technique was also successfully applied to reptiles and fish.
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Kennie, T. J. M., et W. M. McKay. « Monitoring of geotechnical processes by close range photogrammetry ». Geological Society, London, Engineering Geology Special Publications 4, no 1 (1987) : 163–70. http://dx.doi.org/10.1144/gsl.eng.1987.004.01.19.
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AbstractThe role of close range photogrammetry (CRP) in engineering geology is described, the relative advantages and limitations of the technique being outlined. A comprehensive literature review reports on the use of CRP for in situ monitoring of earth and rockfill dams, retaining walls, rockfaces and landslides, channel and gully erosion and, also, laboratory based experiments. The historical development of analytical CRP and the types of project where such a technique would be appropriate are subsequently discussed. Two case histories illustrating the use of analytical CRP for monitoring a series of eroded slopes in southern England are reported. The paper also examines the benefits which occur when digital photogrammetric data of this type are integrated with suitable ground modelling software.
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Ismail, Rifky, Rilo Berdin Taqriban, Mochammad Ariyanto, Ali Tri Atmaja, Sugiyanto, Wahyu Caesarendra, Adam Glowacz, Muhammad Irfan et Witold Glowacz. « Affordable and Faster Transradial Prosthetic Socket Production Using Photogrammetry and 3D Printing ». Electronics 9, no 9 (7 septembre 2020) : 1456. http://dx.doi.org/10.3390/electronics9091456.
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This study aims to invent a new, low-cost, and faster method of prosthetic socket fabrication, especially in Indonesia. In this paper, the photogrammetry with the 3D printing method is introduced as the new applicative way for transradial prosthetic making. Photogrammetry is used to retrieve a 3D model of the amputated hand stump using a digital camera. A digital camera is used for photogrammetry technique and the resulting 3D model is printed using a circular 3D printer with Polylactic acid (PLA) material. The conventional casting socket fabrication method was also conducted in this study as a comparison. Both prosthetic sockets were analyzed for usability, and sectional area conformities to determine the size deviation using the image processing method. This study concludes that the manufacturing of transradial prosthetic sockets incorporating the photogrammetry technique reduces the total man-hour production. Based on the results, it can be implied that the photogrammetry technique is a more efficient and economical method compared to the conventional casting method. The 3D printed socket resulting from the photogrammetry method has a 5–19% area deviation to the casting socket but it is still preferable and adjustable for the transradial amputee when applied to the stump of the remaining hand.
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Pottler, Klaus, Eckhard Lu¨pfert, Glen H. G. Johnston et Mark R. Shortis. « Photogrammetry : A Powerful Tool for Geometric Analysis of Solar Concentrators and Their Components ». Journal of Solar Energy Engineering 127, no 1 (1 février 2005) : 94–101. http://dx.doi.org/10.1115/1.1824109.
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Digital close range photogrammetry has proven to be a precise and efficient measurement technique for the assessment of shape accuracies of solar concentrators and their components. The combination of high quality mega-pixel digital still cameras, appropriate software, and calibrated reference scales in general is sufficient to provide coordinate measurements with precisions of 1:50,000 or better. The extreme flexibility of photogrammetry to provide high accuracy 3D coordinate measurements over almost any scale makes it particularly appropriate for the measurement of solar concentrator systems. It can also provide information for the analysis of curved shapes and surfaces, which can be very difficult to achieve with conventional measurement instruments. The paper gives an overview of quality indicators for photogrammetric networks, which have to be considered during the data evaluation to augment the measurement precision. A selection of measurements done on whole solar concentrators and their components are presented. The potential of photogrammetry is demonstrated by presenting measured effects arising from thermal expansion and gravitational forces on selected components. The measured surface data can be used to calculate slope errors and undertake ray-trace studies to compute intercept factors and assess concentrator qualities.
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Lavorgna, Luca, Gabriele Cervino, Luca Fiorillo, Giovanni Di Leo, Giuseppe Troiano, Marco Ortensi, Luigi Galantucci et Marco Cicciù. « Reliability of a Virtual Prosthodontic Project Realized through a 2D and 3D Photographic Acquisition : An Experimental Study on the Accuracy of Different Digital Systems ». International Journal of Environmental Research and Public Health 16, no 24 (16 décembre 2019) : 5139. http://dx.doi.org/10.3390/ijerph16245139.
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Aims: The study aims to assess the accuracy of digital planning in dentistry, evaluating the characteristics of different intraoral 3D scanners and comparing it with traditional imaging 2D recording methods. Specifically, using computer aided design (CAD) software and measuring inside CAD software, authors want to verify the reliability of different models obtained with different techniques and machines. Methods: 12 patients that needed aesthetic restorative treatment were enrolled in the study. All the patients underwent recording data of the height and width dental elements 1.1, 1.2, and 1.3 size using different technologies and comparing 2D with 3D methods. A T test was then applied in order to verify whether there was a statistically significant difference between the measurements obtained, comparing the different tools data (Emerald, TRIOS, Photogrammetry and DSS (Digital Smile System)) with the reference values. Results: No significant differences emerged in the measurements made with the different scanners (Trios 3Shape ®, Planmeca Emerald ®) and photogrammetry. Therefore, what should be underlined regarding the 2D measurements is the speed and simplicity compared to all 3D techniques, so this work can help to better define the field of application and the limits connected to 2D techniques, giving a good window of the technique. Conclusions: The low number of patients is not sufficient to provide statistically significant results, but the digital planning future prospects seem to be promising. This study results highlighted how a photogrammetric scanner for dental arches would only have a much smaller shooting field size and greater accuracy. Despite these considerations, the photogrammetric facial scanner provided excellent results for the measurement of individual teeth, showing a great versatility of use.
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Edelmers, Edgars, Dzintra Kazoka, Katrina Bolocko et Mara Pilmane. « Different Techniques of Creating Bone Digital 3D Models from Natural Specimens ». Applied System Innovation 5, no 4 (22 août 2022) : 85. http://dx.doi.org/10.3390/asi5040085.
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The choice of technique for the creation of a 3D digital human bone model from natural specimens has a critical impact on the final result and usability of the obtained model. The cornerstone factor in 3D modeling is the number of faces of polygon mesh, along with topological accuracy, as well as resolution and level of detail of the texture map. Three different techniques (3D scanning, photogrammetry, and micro-computed tomography) have been used to create a digital 3D model of the human zygomatic bone. As implementation and use of 3D models can be divided into three main categories—visualization, simulation, and physical replication to obtain a functioning model (implant or prothesis)—the obtained models have been evaluated by the density and topological accuracy of the polygonal mesh, as well as by visual appearance by inspecting the obtained texture map. The obtained data indicate that for biomedical applications and computer biomechanical simulation the most appropriate technique of 3D model obtainment is micro-computed tomography, in its turn for visualization and educational purposes, the photogrammetry technique is a more preferable choice.
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D'Urso, Maria Grazia, et Costantino Luis Marino. « AN APPLICATION OF CLOSE-UP PHOTOGRAMMETRY IN VITICULTURE ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (24 juin 2016) : 1243–50. http://dx.doi.org/10.5194/isprs-archives-xli-b8-1243-2016.
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Within the context of Geomatic-based Agriculture an application of close-up photogrammetry is illustrated with reference to precision farming. The application has been carried out in a particularly attractive archaeological site and concerns some viticulture species produced in situ by following a farming technique dated about two thousand years. Specifically we illustrate and comment the photogrammetric close-range acquisitions, carried out both outdoor and indoor, aimed at producing a digital botanic atlas that can adequately replace the traditional ones drawn by hand. High precision geometric measurements of vineyard leaves and grapes, are suitable indices of their growth rate and an objective estimate of the relevant repening degree.
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D'Urso, Maria Grazia, et Costantino Luis Marino. « AN APPLICATION OF CLOSE-UP PHOTOGRAMMETRY IN VITICULTURE ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (24 juin 2016) : 1243–50. http://dx.doi.org/10.5194/isprsarchives-xli-b8-1243-2016.
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Within the context of Geomatic-based Agriculture an application of close-up photogrammetry is illustrated with reference to precision farming. The application has been carried out in a particularly attractive archaeological site and concerns some viticulture species produced in situ by following a farming technique dated about two thousand years. Specifically we illustrate and comment the photogrammetric close-range acquisitions, carried out both outdoor and indoor, aimed at producing a digital botanic atlas that can adequately replace the traditional ones drawn by hand. High precision geometric measurements of vineyard leaves and grapes, are suitable indices of their growth rate and an objective estimate of the relevant repening degree.
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Ruzgienė, Birutė, Česlovas Aksamitauskas, Ignas Daugėla, Šarūnas Prokopimas, Virgaudas Puodžiukas et Donatas Rekus. « UAV photogrammetry for road surface modelling ». Baltic Journal of Road and Bridge Engineering 10, no 2 (25 juin 2015) : 151–58. http://dx.doi.org/10.3846/bjrbe.2015.19.
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Recently, the interest of Unmanned Aerial Vehicle application in photogrammetric environment for roads observation and monitoring has increased in many countries, in Lithuania as well. The experimental object for demonstration of capability and efficiency of aerial vehicle-based remote sensing technology for road data collection was a western bypass of Vilnius. The platform of the model UX5 Trimble with mounted camera Sony NEX-5R was applied for gaining images. The implemented means are mobile and not expensive. Photogrammetric technique with software package Business Center Photogrammetry Module was applied for the modelling of images. The correctness of digital surface model generally depends on camera resolution, flight height and accuracy of ground control points. The coordinates of control points were determined using Global Positioning System Trimble R4. Paper demonstrates results of a new technology application possibilities for linear object (road) mapping and accuracy evaluation of spatial models. The road points positioning accuracy investigation was carried out in consideration with geodetic control measurements. The average root mean square error for the points coordinates is 2.94 cm, and standard deviations – 2.78 cm. Analyzing coincidence or mismatches of Vilnius western bypass project data with photogrammetric product, not significant discrepancies of road section features were determined. The cost consideration of Unmanned Aerial Vehicle in conjunction with photogrammetry employment at experimental object is presented.
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Fedele, Alessandro, Renato Somma, Claudia Troise, Karen Holmberg, Giuseppe De Natale et Fabio Matano. « Time-Lapse Landform Monitoring in the Pisciarelli (Campi Flegrei-Italy) Fumarole Field Using UAV Photogrammetry ». Remote Sensing 13, no 1 (31 décembre 2020) : 118. http://dx.doi.org/10.3390/rs13010118.
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The utility of new imaging technologies to better understand hazardous geological environments cannot be overstated. The combined use of unmanned aerial vehicles (UAV) and digital photogrammetry (DP) represents a rapidly evolving technique that permits geoscientists to obtain detailed spatial data. This can aid in rapid mapping and analyses of dynamic processes that are modifying contemporary landscapes, particularly through the creation of a time series of digital data to help monitor the geomorphological evolution of volcanic structures. Our study comprises a short-term (in geological terms) monitoring program of the dynamic and diffuse Pisciarelli degassing structure caused by the interplay between intensive rainfall and hydrothermal activity. This area, an unstable fumarole field located several hundred meters east of the Solfatara Crater of the Campi Flegrei caldera (southern Italy), is characterized by consistent soil degassing, fluid emission from ephemeral vents, and hot mud pools. This degassing activity is episodically accompanied by seismic swarms and macroscopic morphology changes such as the appearance of vigorously degassing vents, collapsing landslides, and bubbling mud. In late-2019 and 2020, we performed repeated photogrammetric UAV surveys using the Structure from Motion (SfM) technique. This approach allowed us to create dense 3D point clouds and digital orthophotos spanning one year of surveys. The results highlight the benefits of photogrammetry data using UAV for the accurate remote monitoring and mapping of active volcanoes and craters in harsh and dangerous environments.
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Ma, Shuying, et Kai Zhang. « Low-Altitude Photogrammetry and Remote Sensing in UAV for Improving Mapping Accuracy ». Mobile Information Systems 2022 (14 juillet 2022) : 1–8. http://dx.doi.org/10.1155/2022/5809991.
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The low-altitude photogrammetry technology of unmanned aerial vehicles (UAVs) is widely used in many fields, but the absence of analysis and research affects the accuracy of its data products. At the same time, low-altitude photogrammetry faces the problem of low elevation positioning accuracy. The network space triangulation adjustment in the beam technique region is considered to eliminate perspective distortion in non-overlapping areas. This paper explains the key technologies of low-altitude photography and remote sensing mapping of UAVs, rectifies the distortion difference of remote sensing images, and then carries out grid division on the image according to the improved APAP (as-projective-as-possible warp) matching method. Next, it solves each grid homography matrix, linearizes the homography matrix, and carries out image matching according to the linearized homography matrix, which can effectively weaken the ghosting phenomenon during image matching. The network space triangulation adjustment in the beam technique region is considered to eliminate perspective distortion in non-overlapping areas. The two measurement areas’ accuracy level is analyzed using digital line drawing and digital orthophoto images (DOIs). Finally, the experimental results indicate that the image matching algorithm proposed in this paper has strong reliability and can substantially increase photogrammetric elevation positioning.
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Rickard, William D. A., Jéssica Fernanda Ramos Coelho, Joshua Hollick, Susannah Soon et Andrew Woods. « Application of Photogrammetric 3D Reconstruction to Scanning Electron Microscopy : Considerations for Volume Analysis ». Electronic Imaging 2021, no 18 (18 janvier 2021) : 60404–1. http://dx.doi.org/10.2352/issn.2470-1173.2021.18.3dia-102.
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Photogrammetric three-dimensional (3D) reconstruction is an image processing technique used to develop digital 3D models from a series of two-dimensional images. This technique is commonly applied to optical photography though it can also be applied to microscopic imaging techniques such as scanning electron microscopy (SEM). The authors propose a method for the application of photogrammetry techniques to SEM micrographs in order to develop 3D models suitable for volumetric analysis. SEM operating parameters for image acquisition are explored and the relative effects discussed. This study considered a variety of microscopic samples, differing in size, geometry and composition, and found that optimal operating parameters vary with sample geometry. Evaluation of reconstructed 3D models suggests that the quality of the models strongly determines the accuracy of the volumetric measurements obtainable. In particular, they report on volumetric results achieved from a laser ablation pit and discuss considerations for data acquisition routines.
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Fais, Silvana, Francesco Cuccuru, Giuseppe Casula, Maria Giovanna Bianchi et Paola Ligas. « Characterization of Rock Samples by A High-Resolution Multi-Technique Non-Invasive Approach ». Minerals 9, no 11 (29 octobre 2019) : 664. http://dx.doi.org/10.3390/min9110664.
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Three different non-invasive techniques, namely Structure from Motion (SfM) photogrammetry, Terrestrial Laser Scanner (TLS) and ultrasonic tomography integrated with petrographic data, were applied to characterize two rock samples of a different nature: A pyroclastic rock and a carbonate rock. We started a computation of high-resolution 3D models of the two samples using the TLS technique supported by a digital SfM photogrammetry survey. The resulting radiometric information available, such as reflectivity maps, SfM photogrammetry textured models and patterns of geometrical residuals, were interpreted in order to detect and underline surface materials anomalies by a comparison of reflectance and natural colour anomalies. Starting from the 3D models from previous techniques, a 3D ultrasonic tomography on each rock sample was accurately planned and carried out in order to detect internal defects or sample heterogeneity. The integration of the above three geophysical non-invasive techniques with petrographical data—especially with the textural characteristics of such materials—represents a powerful method for the definition of the heterogeneity of the rocks at a different scale and for calibrating in situ measurements.
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Lane, S. N., K. S. Richards et J. H. Chandler. « Developments in photogrammetry ; the geomorphological potential ». Progress in Physical Geography : Earth and Environment 17, no 3 (septembre 1993) : 306–28. http://dx.doi.org/10.1177/030913339301700302.
Texte intégralRésumé :
Current emphasis in geomorphology recognizes the need for the accurate representation of topographic form, reflected in the growth of digital terrain and elevation modelling. A key requirement of such strategies is the efficient acquisition of information in an appropriate form and at an appropriate resolution to the landform under consideration. The traditional use of photographs in geomorphology has been for interpretation, but developments in photogrammetry may allow the full advantages of the photograph as a means of acquiring and storing quantitative information to be used. The photograph can provide information on all areas visible on a photograph; the information is acquired retrodictively; the photograph preserves the spatial relationship of morphological units; the collection of photographs requires minimal landform contact; the photograph records extra explanatory information; and photographs can be obtained at an appropriate temporal resolution to the landform under investigation. However, optical and mechanical limitations imposed by traditional photogrammetric approaches have prevented its rigorous and widespread application to geomorphology. Developments within photogrammetry, notably the analytical approach, now open up wider geomorphological possibilities. The analytical approach overcomes these limitations through the use of an interactive mathematical model at the stage of photographic analysis. The obtained information is in a form directly suited to the construction of digital terrain or elevation models. This technique can be used both for landform monitoring and for the analysis of archival photographs to reconstruct historical landform change.
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Wong, Julielynn Y., Albert K. Oh, Eiichi Ohta, Anne T. Hunt, Gary F. Rogers, John B. Mulliken et Curtis K. Deutsch. « Validity and Reliability of Craniofacial Anthropometric Measurement of 3D Digital Photogrammetric Images ». Cleft Palate-Craniofacial Journal 45, no 3 (mai 2008) : 232–39. http://dx.doi.org/10.1597/06-175.
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Background: Direct anthropometry performed during a patient examination is the standard technique for quantifying craniofacial dysmorphology, as well as for surgical planning and outcome assessment. Several new technologies have been designed to computerize anthropometric measurements, including three-dimensional (3D) digital photogrammetry. These digital systems have the advantage of acquiring patient craniofacial surface images quickly and noninvasively. Before morphometry using digital photogrammetry can be applied in clinical and research practice, it must be assessed against direct anthropometry. Objective: To evaluate the validity and reliability of facial anthropometric linear distances imaged by 3D digital photogrammetry with respect to direct anthropometry. Design, Setting, Participants, Measures: Standard craniofacial distances were directly measured twice on 20 normal adult volunteers. Craniofacial surfaces were also imaged using the 3dMDface digital photogrammetry system, and distances were digitally measured twice for each subject. Validity measures of accuracy and bias (for direct versus digital measurements) and reproducibility measures of precision and test-retest reliability (for repeated sets of digital measurements) were computed. Results: Seventeen of the 18 direct measurements correlated highly with digital values (mean r = 0.88). The correlation for one measurement (upper prolabial width) was not statistically significant. The overall precision of all 17 digital measurements was less than 1 mm, and the reliability was high (mean r = 0.91). Conclusions: Craniofacial anthropometry using the 3dMDface System is valid and reliable. Digital measurements of upper prolabial width may require direct marking, prior to imaging, to improve landmark identification.
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Sturzenegger, M., et D. Stead. « Quantifying discontinuity orientation and persistence on high mountain rock slopes and large landslides using terrestrial remote sensing techniques ». Natural Hazards and Earth System Sciences 9, no 2 (3 mars 2009) : 267–87. http://dx.doi.org/10.5194/nhess-9-267-2009.
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Abstract. This paper describes experience gained in the application of terrestrial digital photogrammetry and terrestrial laser scanning for the characterization of the structure of high mountain rock slopes and large landslides. A methodology allowing the creation and registration of 3-D models with limited access to high mountain rock slopes is developed and its accuracy verified. The importance of occlusion, ground resolution, scale and reflectivity are discussed. Special emphasis is given to the concept of observation scale and resulting scale bias and its influence on discontinuity characterization. The step-path geometry of persistent composite surfaces and its role in remote sensing measurements are described. An example of combined terrestrial digital photogrammetry and terrestrial laser scanning applied in the generation of a 3-D model of the South Peak of Turtle Mountain, the location of the Frank Slide, is presented. The advantages gained from the combined use of these techniques and the potential offered through long-range terrestrial digital photogrammetry, using high focal length lenses up to 400 mm is illustrated. Special emphasis is given to the potential of this specific technique, which has to the authors knowledge rarely been documented in the geotechnical literature.
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Salagean-Mohora, Irina, Anamaria Andreea Anghel et Flaviu Mihai Frigura-Iliasa. « Photogrammetry as a Digital Tool for Joining Heritage Documentation in Architectural Education and Professional Practice ». Buildings 13, no 2 (20 janvier 2023) : 319. http://dx.doi.org/10.3390/buildings13020319.
Texte intégralRésumé :
Given the accelerated technological advance in all fields, vast knowledge of digital tools becomes mandatory for future interior designers and architects. Thus, experimenting with as many such methods and technologies must become a priority for the teaching process. Noticing a high demand for digitalization during the COVID-19 pandemic, the Polytechnic University of Timisoara has decided to encourage the implementation of digital teaching throughout disciplines, preparing students for their future careers. Photogrammetry as a study method, among others, has the potential to outrank traditional documentation techniques currently applied in architectural education and practice. The presented research was divided into two main phases: an educational, experimental workshop and a project restoration application. After learning, testing, and refining the close-range photogrammetry workflow, the authors and students took the best practices and applied them to an ongoing facade restoration project in Timisoara, scanning original and restored plaster ornaments and finally 3D printing one of the models. The article aims to show that, unlike traditional teaching methods, using photogrammetry as a documentation process creates a coherent link between theoretical education and restoration practice. Consequently, the exercise brings students closer to the applicable side of their careers through a contemporary digital technique.
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Turchini, John, Michael E. Buckland, Anthony J. Gill et Shane Battye. « Three-Dimensional Pathology Specimen Modeling Using “Structure-From-Motion” Photogrammetry : A Powerful New Tool for Surgical Pathology ». Archives of Pathology & ; Laboratory Medicine 142, no 11 (30 mai 2018) : 1415–20. http://dx.doi.org/10.5858/arpa.2017-0145-oa.
Texte intégralRésumé :
Context.— Three-dimensional (3D) photogrammetry is a method of image-based modeling in which data points in digital images, taken from offset viewpoints, are analyzed to generate a 3D model. This modeling technique has been widely used in the context of geomorphology and artificial imagery, but has yet to be used within the realm of anatomic pathology. Objective.— To describe the application of a 3D photogrammetry system capable of producing high-quality 3D digital models and its uses in routine surgical pathology practice as well as medical education. Design.— We modeled specimens received in the 2 participating laboratories. The capture and photogrammetry process was automated using user control software, a digital single-lens reflex camera, and digital turntable, to generate a 3D model with the output in a PDF file. Results.— The entity demonstrated in each specimen was well demarcated and easily identified. Adjacent normal tissue could also be easily distinguished. Colors were preserved. The concave shapes of any cystic structures or normal convex rounded structures were discernable. Surgically important regions were identifiable. Conclusions.— Macroscopic 3D modeling of specimens can be achieved through Structure-From-Motion photogrammetry technology and can be applied quickly and easily in routine laboratory practice. There are numerous advantages to the use of 3D photogrammetry in pathology, including improved clinicopathologic correlation for the surgeon and enhanced medical education, revolutionizing the digital pathology museum with virtual reality environments and 3D-printing specimen models.
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Costa, E., C. Balletti, C. Beltrame, F. Guerra et P. Vernier. « DIGITAL SURVEY TECHNIQUES FOR THE DOCUMENTATION OF WOODEN SHIPWRECKS ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B5 (15 juin 2016) : 237–42. http://dx.doi.org/10.5194/isprs-archives-xli-b5-237-2016.
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Nowadays, researchers widely employ the acquisition of point clouds as one of the principal type of documentation for cultural heritage. In this paper, different digital survey techniques are employed to document a wooden ancient shipwreck, a particular and difficult kind of archaeological finding due to its material characteristics. The instability of wood and the high costs of restoration do not always offer the opportunity of recovering and showing the hull to researchers and public and three-dimensional surveys are fundamental to document the original conditions of the wood. The precarious conditions of this material in contact with air could modify the structure and the size of the boat, requiring a fast and accurate recording technique. The collaboration between Ca' Foscari University and the Laboratory of Photogrammetry of Iuav University of Venice has given the possibility to demonstrate the utility of these technology. We have surveyed a sewn boat of Roman age through multi-image photogrammetry and laser scanner. Point clouds were compared and a residual analysis was done, to verify the characteristics and the opportunity of the two techniques, both of them have allowed obtaining a very precise documentation from a metrical point of view.
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Costa, E., C. Balletti, C. Beltrame, F. Guerra et P. Vernier. « DIGITAL SURVEY TECHNIQUES FOR THE DOCUMENTATION OF WOODEN SHIPWRECKS ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B5 (15 juin 2016) : 237–42. http://dx.doi.org/10.5194/isprsarchives-xli-b5-237-2016.
Texte intégralRésumé :
Nowadays, researchers widely employ the acquisition of point clouds as one of the principal type of documentation for cultural heritage. In this paper, different digital survey techniques are employed to document a wooden ancient shipwreck, a particular and difficult kind of archaeological finding due to its material characteristics. The instability of wood and the high costs of restoration do not always offer the opportunity of recovering and showing the hull to researchers and public and three-dimensional surveys are fundamental to document the original conditions of the wood. The precarious conditions of this material in contact with air could modify the structure and the size of the boat, requiring a fast and accurate recording technique. The collaboration between Ca' Foscari University and the Laboratory of Photogrammetry of Iuav University of Venice has given the possibility to demonstrate the utility of these technology. We have surveyed a sewn boat of Roman age through multi-image photogrammetry and laser scanner. Point clouds were compared and a residual analysis was done, to verify the characteristics and the opportunity of the two techniques, both of them have allowed obtaining a very precise documentation from a metrical point of view.
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Berteška, Tautvydas, et Birutė Ruzgienė. « PHOTOGRAMMETRIC MAPPING BASED ON UAV IMAGERY ». Geodesy and Cartography 39, no 4 (18 décembre 2013) : 158–63. http://dx.doi.org/10.3846/20296991.2013.859781.
Texte intégralRésumé :
Unmanned Aerial Vehicle (UAV) and Digital Photogrammetry is an up-to-date area mapping technology. Implemented features are low-cost, mobile and simple. UAV (fixed-wing EPP-FPV) with mounted digital camera (Canon S100) was used for imagery while digital photogrammetry processing (with lisa software application) was applied for cartographic data collection. High imagery quality is a significant factor for the efficiency and quality of standard mapping products, such as Digital Elevation Model and Ortho Images. DEM and Orthophoto quality mainly depends on camera resolution, flight height and accuracy of Ground Control Points (GCP). In experimental investigations, GCP coordinates were gained interactively from the Internet. Application of the appropriate DEM checking technique showed that DEM error was up to 0.5 m.
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Hairuddin, A., S. Azri, U. Ujang, M. G. Cuétara, G. M. Retortillo et S. Mohd Salleh. « DEVELOPMENT OF 3D CITY MODEL USING VIDEOGRAMMETRY TECHNIQUE ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W16 (1 octobre 2019) : 221–28. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w16-221-2019.
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Abstract. 3D city model is a representation of urban area in digital format that contains building and other information. The current approaches are using photogrammetry and laser scanning to develop 3D city model. However, these techniques are time consuming and quite costly. Besides that, laser scanning and photogrammetry need professional skills and expertise to handle hardware and tools. In this study, videogrammetry is proposed as a technique to develop 3D city model. This technique uses video frame sequences to generate point cloud. Videos are processed using EyesCloud3D by eCapture. EyesCloud3D allows user to upload raw data of video format to generate point clouds. There are five main phases in this study to generate 3D city model which are calibration, video recording, point cloud extraction, 3D modeling and 3D city model representation. In this study, 3D city model with Level of Detail 2 is produced. Simple query is performed from the database to retrieve the attributes of the 3D city model.
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Ahmed, Mahmoud, C. T. Haas et Ralph Haas. « Using digital photogrammetry for pipe-works progress tracking1This paper is one of a selection of papers in this Special Issue on Construction Engineering and Management. » Canadian Journal of Civil Engineering 39, no 9 (septembre 2012) : 1062–71. http://dx.doi.org/10.1139/l2012-055.
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Pipe-works are among the most complicated items to be tracked in the course of monitoring construction project progress. Traditionally, the tracking of pipe-works progress is conducted either manually or using laser scanning technology. While laser scanning is a 3D imaging technique, and commercial software exists to construct 3D CAD models of piping based on such images, it suffers from portability, purchase cost, and other disadvantages. This paper describes digital photogrammetry technology as an alternative for pipe-works reconstruction and as a cost effective tracking tool. For validation, data was collected using a handheld digital camera to acquire images inside a new building under construction. Progress of the pipe-work networks of different types and sizes in the new building was monitored during the construction phases. In addition to the known accuracy and robustness of photogrammetry, it was found that the use of digital photogrammetry provided a practical and low-cost approach.
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López-Menchero Bendicho, Víctor Manuel, Ángel Marchante Ortega, Matthew Vincent, Ángel Javier Cárdenas Martín-Buitrago et Jorge Onrubia Pintado. « Uso combinado de la fotografía digital nocturna y de la fotogrametría en los procesos de documentación de petroglifos : el caso de Alcázar de San Juan (Ciudad Real, España) ». Virtual Archaeology Review 8, no 17 (26 juillet 2017) : 64. http://dx.doi.org/10.4995/var.2017.6820.
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For decades, the documentation of rock art has been the backbone of the research on this cultural practice. However, traditional techniques used for this purpose have proved to be imprecise and subjective. With the advent of the digital age there has been a revolution in the field of rock art documentation in general and in particular for petroglyphs. Techniques such as digital nightlight photography or three-dimensional (3D) photogrammetry have opened a world of possibilities. In the case of nightlight photography, its use goes back to the second half of the 20th century. However, in recent years the emergence of high-power digital cameras along with new lighting systems unthinkable decades ago, such as tactical flashlights, have rejuvenated a technique that seems incombustible. After the numerous tests carried out by the DIPAR (Integral Rock Art Documentation System) project team, it has become evident that, correctly employed, this technique still has immense potential in the field of rock art documentation, especially if we take into consideration its low cost and ease of use. Photogrammetry, on the other hand, is shown as the perfect complement to the records obtained through digital nightlight photography. The possibility of applying filters or shaders that increase the visibility of the digitized petroglyphs, within a metric scheme, is a great advance in their documentation. This paper explores the advantages associated with these techniques with a case study: unpublished petroglyphs of Alcázar de San Juan (Spain).
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Farah, Ashraf, Ashraf Talaat et Farrag Farrag. « Accuracy Assessment of Digital Elevation Models Using GPS ». Artificial Satellites 43, no 4 (1 janvier 2008) : 151–61. http://dx.doi.org/10.2478/v10018-009-0014-7.
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Accuracy Assessment of Digital Elevation Models Using GPSA Digital Elevation Model (DEM) is a digital representation of ground surface topography or terrain with different accuracies for different application fields. DEM have been applied to a wide range of civil engineering and military planning tasks. DEM is obtained using a number of techniques such as photogrammetry, digitizing, laser scanning, radar interferometry, classical survey and GPS techniques. This paper presents an assessment study of DEM using GPS (Stop&Go) and kinematic techniques comparing with classical survey. The results show that a DEM generated from (Stop&Go) GPS technique has the highest accuracy with a RMS error of 9.70 cm. The RMS error of DEM derived by kinematic GPS is 12.00 cm.
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Pavelka, Karel, et Jan Řezníček. « New Low-Cost Automated Processing of Digital Photos for Documentation and Visualisation of the Cultural Heritage ». Geoinformatics FCE CTU 6 (21 décembre 2011) : 249–58. http://dx.doi.org/10.14311/gi.6.31.
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The 3D scanning is nowadays a commonly used and fast technique. A variety of type’s 3D scanners is available, with different precision and aim of using. From normal user´s point of view, all the instruments are very expensive and need special software for processing the measured data. Also transportation of 3D scanners – poses a problem, because duty or special taxes for transport out of the EU have to be paid and there is a risk of damage to dismantling of these very expensive instruments and calibration will be needed. For this reason, a simple and automated technique using close range photogrammetry documentation is very important. This paper describes our experience with the software solution for automatic image correlation techniques and their utilization in close range photogrammetry and historical objects documentation. Non-photogrammetrical approach, which often gives very good outputs, is described the last part of this contribution. An image correlation proceeds well only on appropriate parts of documented objects and depends on the number of images, their overlapping and configuration, radiometrical quality of photos, and surface texture.
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Cullen, Sean, Ruth Mackay, Amir Mohagheghi et Xinli Du. « The Use of Smartphone Photogrammetry to Digitise Transtibial Sockets : Optimisation of Method and Quantitative Evaluation of Suitability ». Sensors 21, no 24 (16 décembre 2021) : 8405. http://dx.doi.org/10.3390/s21248405.
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The fit of a lower limb prosthetic socket is critical for user comfort and the quality of life of lower limb amputees. Sockets are conventionally produced using hand-crafted patient-based casting techniques. Modern digital techniques offer a host of advantages to the process and ultimately lead to improving the lives of amputees. However, commercially available scanning equipment required is often expensive and proprietary. Smartphone photogrammetry could offer a low cost alternative, but there is no widely accepted imaging technique for prosthetic socket digitisation. Therefore, this paper aims to determine an optimal imaging technique for whole socket photogrammetry and evaluate the resultant scan measurement accuracy. A 3D printed transtibial socket was produced to create digital and physical twins, as reference models. The printed socket was photographed from 360 positions and simplified genetic algorithms were used to design a series of experiments, whereby a collection of photos were processed using Autodesk ReCap. The most fit technique was used to assess accuracy. The accuracy of the socket wall volume, surface area and height were 61.63%, 99.61% and 99.90%, respectively, when compared to the digital reference model. The scanned model had a wall thickness ranging from 2.075 mm at the top to 7.758 mm towards the base of the socket, compared to a consistent thickness of 2.025 mm in the control model. The technique selected did not show sufficient accuracy for clinical application due to the degradation of accuracy nearer to the base of the socket interior. However, using an internal wall thickness estimation, scans may be of sufficient accuracy for clinical use; assuming a uniform wall thickness.
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Betlem, Peter, Thomas Birchall, Kei Ogata, Joonsang Park, Elin Skurtveit et Kim Senger. « Digital Drill Core Models : Structure-from-Motion as a Tool for the Characterisation, Orientation, and Digital Archiving of Drill Core Samples ». Remote Sensing 12, no 2 (19 janvier 2020) : 330. http://dx.doi.org/10.3390/rs12020330.
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Structure-from-motion (SfM) photogrammetry enables the cost-effective digital characterisation of seismic- to sub-decimetre-scale geoscientific samples. The technique is commonly used for the characterisation of outcrops, fracture mapping, and increasingly so for the quantification of deformation during geotechnical stress tests. We here apply SfM photogrammetry using off-the-shelf components and software, to generate 25 digital drill core models of drill cores. The selected samples originate from the Longyearbyen CO2 Lab project’s borehole DH4, covering the lowermost cap rock and uppermost reservoir sequences proposed for CO2 sequestration onshore Svalbard. We have come up with a procedure that enables the determination of bulk volumes and densities with precisions and accuracies similar to those of such conventional methods as the immersion in fluid method. We use 3D printed replicas to qualitatively assure the volumes, and show that, with a mean deviation (based on eight samples) of 0.059% compared to proven geotechnical methods, the photogrammetric output is found to be equivalent. We furthermore splice together broken and fragmented core pieces to reconstruct larger core intervals. We unwrap these to generate and characterise 2D orthographic projections of the core edge using analytical workflows developed for the structure-sedimentological characterisation of virtual outcrop models. Drill core orthoprojections can be treated as directly correlatable to optical borehole-wall imagery data, enabling a direct and cost-effective elucidation of in situ drill core orientation and depth, as long as any form of borehole imagery is available. Digital drill core models are thus complementary to existing physical and photographic sample archives, and we foresee that the presented workflow can be adopted for the digitisation and digital storage of other types of geological samples, including degradable and dangerous ice and sediment cores and samples.
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Truong Nguyen, G., et N. Seube. « FORMAP : A SIMPLE AND FAST PHOTOGRAMMETRY FRAMEWORK FOR DIRECT GEO-REFERENCING SYSTEMS ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W17 (29 novembre 2019) : 385–91. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w17-385-2019.
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Abstract. This paper presents FORMap (Fast Ortho Mapping) a simple, automatic, fast and accurate commercial photogrammetry processing software for Unmanned Aerial Vehicles (UAV) imagery equiped with Direct Georeferencing (DG) technology. DG technique allows user to directly geo-reference the acquisition without the use of Ground Control Points (GCP) by providing image external orientation (EO) parameters in a mapping frame. However, it requires a sensor of relatively high quality to provide an accurate EO with each image shot, which is somehow limited by the light weight of UAV payloads. FORMap makes use of EO information delivered by DG as an a priori information to accelerate its photogrammetric processing. We present the functionalities and some application of FORMap in the field of UAV mapping. We evaluate its accuracy and its robustness on several datasets. Test result shows that FORMap is robust for 3D scene reconstruction despite of inaccuracies of DG input data. It is also faster than standard digital photogrammetry solution based on SfM (Structure from Motion) approach and can provide orthophotos and dense point cloud in quasi real-time.
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Knyaz, V. A., A. A. Maksimov, M. M. Novikov et A. V. Urmashova. « AUTOMATIC ANTHROPOLOGICAL LANDMARKS RECOGNITION AND MEASUREMENTS ». International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIV-2/W1-2021 (15 avril 2021) : 137–42. http://dx.doi.org/10.5194/isprs-archives-xliv-2-w1-2021-137-2021.
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Abstract. Many anthropological researches require identification and measurement of craniometric and cephalometric landmarks which provide valuable information about the shape of a head. This information is necessary for morphometric analysis, face approximation, craniafacial identification etc. Traditional techniques use special anthropological tools to perform required measurements, identification of landmarks usually being made by an expert-anthropologist. Modern techniques of optical 3D measurements such as photogrammetry, computer tomography, laser 3D scanning provide new possibilities for acquiring accurate 2D and 3D data of high resolution, thus creating new conditions for anthropological data analysis. Traditional anthropological manual point measurements can be substituted by analysis of accurate textured 3D models, which allow to retrieve more information about studied object and easily to share data for independent analysis. The paper presents the deep learning technique for anthropological landmarks identification and accurate 3D measurements. Photogrammetric methods and their practical implementation in the automatic system for accurate digital 3D reconstruction of anthropological objects are described.
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Altman, S., W. Xiao et B. Grayson. « EVALUATION OF LOW-COST TERRESTRIAL PHOTOGRAMMETRY FOR 3D RECONSTRUCTION OF COMPLEX BUILDINGS ». ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-2/W4 (13 septembre 2017) : 199–206. http://dx.doi.org/10.5194/isprs-annals-iv-2-w4-199-2017.
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Terrestrial photogrammetry is an accessible method of 3D digital modelling, and can be done with low-cost consumer grade equipment. Globally there are many undocumented buildings, particularly in the developing world, that could benefit from 3D modelling for documentation, redesign or restoration. Areas with buildings at risk of destruction by natural disaster or war could especially benefit. This study considers a range of variables that affect the quality of photogrammetric results. Different point clouds of the same building are produced with different variables, and they are systematically tested to see how the output was affected. This is done by geometrically comparing them to a laser scanned point cloud of the same building. It finally considers how best results can be achieved for different applications, how to mitigate negative effects, and the limits of this technique.
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Zhao, Hu, San Gen Wang et Da Ke Wu. « Application of Digital Close Range Photogrammetry in Mechanical Three-Dimensional Modeling ». Advanced Materials Research 189-193 (février 2011) : 1973–77. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.1973.
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It is usually a time-consuming process to set up three-dimensinal(3D) model of mechanical components with complex surface. In order to solve the problem, this paper adopts consumer cameras and the technique of digital close range photogrammetry ( DCRP ) to establish 3D model, and export the data to 3D mechanical design software (SolidWorks) for further simulation and reconstruction. This method has been proved very effective in practise.
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Su, Fa. « The Fast Measuring and Processing Method of 3D Measuring System in Reverse Designing ». Advanced Materials Research 291-294 (juillet 2011) : 2471–75. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.2471.
Texte intégralRésumé :
The paper introduce that composing, principle and application example of a 3D Measuring system. It mainly applies technique of digital image processing, photogrammetry, optical grating measuring technique , in order to measure rapidly and correctly geometric data of a 3D –Object’ surface,Spots clouds data can be processed by ATOS system’s soft. The system supplys a rapid method to product fast measuring.
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Tohme, Hani, Ghida Lawand, Rita Eid, Khaled E. Ahmed, Ziad Salameh et Joseph Makzoume. « Accuracy of Implant Level Intraoral Scanning and Photogrammetry Impression Techniques in a Complete Arch with Angled and Parallel Implants : An In Vitro Study ». Applied Sciences 11, no 21 (22 octobre 2021) : 9859. http://dx.doi.org/10.3390/app11219859.
Texte intégralRésumé :
(1) Background: Stereophotogrammetry has recently been investigated showing high accuracy in complete implant supported cases but has scarcely been investigated in cases of tilted implants. The aim of this in vitro study was to compare the accuracy of digital impression techniques (intraoral scanning and photogrammetry) at the level of intraoral scan bodies in terms of angular deviations and 3D discrepancies. (2) Methods: A stone master cast representing an edentulous maxilla using four implant analogs was fabricated. The two anterior implants were parallel to each other, and the two posterior implants were at an angulation of 17 degrees. Digital intraoral scanning (DIOS) impressions were taken after connecting implant level scan bodies to the master cast and STL files were exported (n = 15). Digital photogrammetry (DPG) impressions were captured using a PiC Camera after tightening implant level PiC optical markers and STL files were exported (n = 15). Superimposition was carried out by a software for determining the accuracy of both. (3) Results: Significant angular discrepancies (ΔA) and 3D deviations of scan bodies were found among the groups in trueness with lower deviations for the DPG (p value < 0.001). However, trueness within ISBs varied between angular and 3D deviations and outcomes were not specific to determine the effect of implant angulation. In precision, no significant differences were detected within ISBs and among both groups in terms of angular deviation. However, DPG had less deviations than DIOS group in terms of 3D deviations (p value < 0.001). (4) Conclusion: Digital photogrammetry technique conveyed the utmost accuracy in both trueness and precision for the intraoral scan bodies among both impression methods assessed. In addition, implant angulation did not influence the precision of the impression techniques but affected their trueness without explicit conclusions.
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Waheed, Zarinah, Daniella Han et Muhammad Ali Syed Hussein. « Mapping coral reef using photogrammetry technique : A preliminary study at Pulau Udar Besar, Sabah, Malaysia. » Borneo Journal of Marine Science and Aquaculture (BJoMSA) 5, no 2 (31 décembre 2021) : 70–74. http://dx.doi.org/10.51200/bjomsa.v5i2.2604.
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Mapping of coral reefs is useful for understanding, monitoring and tracking their development. However, studies on reef mapping in the Southeast Asian region are limited. The main objectives of this study were to 1) map the coral reefs using photogrammetry in order to create a 3D map of the reef, and 2) determine the coral growth forms and identify the corals to the lowest possible taxa from the images. Data collection was conducted on 19 and 24 January 2018. All images were captured by applying photogrammetry technique using a digital camera with waterproof housing. Image reconstruction process was performed in Agisoft Photoscan and Blender, using the structure-from-motion (SfM) algorithms to reconstruct the 2-Dimensional images into a 3D model. The reef map generated from Agisoft Photoscan is of medium quality. Coral growth forms were determined and identified to the lowest possible taxa through the images. From the images, free-living corals of the family Fungiidae were the most common coral observed in the study site. In conclusion, the output of this study shows that reef mapping is possible using a photogrammetry approach and images can be used to identify coral growth forms.
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Li, Hao, Yun Cai, Biao Yang et Ming Fei Wu. « A Fast Geological Logging Technique of Underground Coal Mines Based on Photogrammetry ». Advanced Materials Research 663 (février 2013) : 661–67. http://dx.doi.org/10.4028/www.scientific.net/amr.663.661.
Texte intégralRésumé :
Aiming at the deficiency of current geological logging method on the coal working face, the geological logging information system for coal mines based on digital camera is developed, integrating techniques of photogrammetry, graphic and image processing, and GIS. Emphasis is mainly placed on the fast acquisition of images from coal mining and excavation faces, photographic information processing and geological logging method, thus achieving the integrated work pattern of data acquisition, computer-aided processing and logging mapping. The experiment shows that by applying the fast geological logging technique of coal mines, the logging result which is accurate, authentic, reliable and satisfies the current requirements can be obtained, improving the work efficiency and result quality, therefore providing a new means and approach for geological logging of underground coal mines.
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Li, Ming Ming, Jian Gong Chen et Yong Xing Zhang. « The Application of Close-Range Digital Photogrammetry Based on the Neural Network in Crack-Monitoring ». Applied Mechanics and Materials 90-93 (septembre 2011) : 2875–80. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.2875.
Texte intégralRésumé :
Based on the two-dimensional Direct Linear Transformation (DLT) principle of close-range digital photogrammetry and mathematical principle of the linear neuron, the equivalent relationship between linear neural network and the two-dimensional DLT of close-range digital photogrammetry is discussed. A neural network with 2 linear neurons, 6 input parameters and 2 output parameters is established to simulate the two-dimensional DLT. The network can be trained using a set of grid points in the control coordinate system with known world coordinates and pixel coordinates. The weights and biases of trained network contain camera interior and exterior parameters. A new digital photographic technique is put forward combined camera self-calibration based on neural network with non-linear pixel coordinates correction of lens distortion. The indoor survey test indicates that measurement is more accuracy. Meanwhile, the new technology is successfully used in crack monitor of a bridge pier.
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Badr, Ahmed Mangoud, Wael M. Mubarak Refai, Mohamed Gaber El-Shal et Ahmed Nasef Abdelhameed. « Accuracy and Reliability of Kinect Motion Sensing Input Device’s 3D Models : A Comparison to Direct Anthropometry and 2D Photogrammetry ». Open Access Macedonian Journal of Medical Sciences 9, no D (14 mai 2021) : 54–60. http://dx.doi.org/10.3889/oamjms.2021.6006.
Texte intégralRésumé :
AIM: This study aims to evaluate the accuracy and reliability of Kinect motion sensing input device’s three-dimensional (3D) models by comparing it with direct anthropometry and digital 2D photogrammetry. MATERIALS AND METHODS: Six profiles and four frontal parameters were directly measured on the faces of 80 participants. The same measurements were repeated using two-dimensional (2D) photogrammetry and (3D) images obtained from Kinect device. Another observer made the same measurements for 30% of the images obtained with 3D technique, and interobserver reproducibility was evaluated for 3D images. Intraobserver reproducibility was evaluated. Statistical analysis was conducted using the paired samples t-test, interclass correlation coefficient, and Bland-Altman limits of agreement. RESULTS: The highest mean difference was 0.0084 mm between direct measurement and photogrammetry, 0.027 mm between direct measurement and 3D Kinect’s models, and 0.018 mm between photogrammetry and 3D Kinect’s. The lowest agreement value was 0.016 in the all parameter between the photogrammetry and 3D Kinect’s methods. Agreement between the two observers varied from 0.999 Sn-Me to 1 with the rest of linear measurements. CONCLUSION: Measurements done using 3D Images obtained from Kinect device indicate that it may be an accurate and reliable imaging method for use in orthodontics. It also provides an easy low-cost 3D imaging technique that has become increasingly popular in clinical settings, offering advantages for surgical planning and outcome evaluation.
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Banfi, Fabrizio, et Alessandro Mandelli. « Computer Vision Meets Image Processing and UAS PhotoGrammetric Data Integration : From HBIM to the eXtended Reality Project of Arco della Pace in Milan and Its Decorative Complexity ». Journal of Imaging 7, no 7 (16 juillet 2021) : 118. http://dx.doi.org/10.3390/jimaging7070118.
Texte intégralRésumé :
This study aims to enrich the knowledge of the monument Arco della Pace in Milan, surveying and modelling the sculpture that crowns the upper part of the building. The statues and the decorative apparatus are recorded with the photogrammetric technique using both a terrestrial camera and an Unmanned Aerial Vehicle (UAV). Research results and performance are oriented to improve computer vision and image processing integration with Unmanned Aerial System (UAS) photogrammetric data to enhance interactivity and information sharing between user and digital heritage models. The vast number of images captured from terrestrial and aerial photogrammetry will also permit to use of the Historic Building Information Modelling (HBIM) model in an eXtended Reality (XR) project developed ad-hoc, allowing different types of users (professionals, non-expert users, virtual tourists, and students) and devices (mobile phones, tablets, PCs, VR headsets) to access details and information that are not visible from the ground.