scholarly journals 3D RECONSTRUCTION OF AN UNDERWATER ARCHAELOGICAL SITE: COMPARISON BETWEEN LOW COST CAMERAS

2015 ◽  
Vol XL-5/W5 ◽  
pp. 67-72 ◽  
Author(s):  
A. Capra ◽  
M. Dubbini ◽  
E. Bertacchini ◽  
C. Castagnetti ◽  
F. Mancini
Keyword(s):  
3D Reconstruction ◽  
Low Cost ◽  
3D Models ◽  
Digital Cameras ◽  
Discussion Section ◽  
Sea Bottom ◽  
Digital Format ◽  
Starting Point ◽  
Submerged Objects ◽  
Submerged Area

The 3D reconstruction with a metric content of a submerged area, where objects and structures of archaeological interest are found, could play an important role in the research and study activities and even in the digitization of the cultural heritage. The reconstruction of 3D object, of interest for archaeologists, constitutes a starting point in the classification and description of object in digital format and for successive fruition by user after delivering through several media. The starting point is a metric evaluation of the site obtained with photogrammetric surveying and appropriate 3D restitution. The authors have been applying the underwater photogrammetric technique since several years using underwater digital cameras and, in this paper, digital low cost cameras (off-the-shelf). Results of tests made on submerged objects with three cameras are presented: © Canon Power Shot G12, © Intova Sport HD e © GoPro HERO 2. The experimentation had the goal to evaluate the precision in self-calibration procedures, essential for multimedia underwater photogrammetry, and to analyze the quality of 3D restitution. Precisions obtained in the calibration and orientation procedures was assessed by using three cameras, and an homogeneous set control points. Data were processed with © Agisoft Photoscan. Successively, 3D models were created and the comparison of the models derived from the use of different cameras was performed. Different potentialities of the used cameras are reported in the discussion section. The 3D restitution of objects and structures was integrated with sea bottom floor morphology in order to achieve a comprehensive description of the site. A possible methodology of survey and representation of submerged objects is therefore illustrated, considering an automatic and a semi-automatic approach.

scholarly journals A Low-Cost and Ultralight Unmanned Aerial Vehicle-Borne Multicamera Imaging System Based on Smartphones

2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Huachao Yang ◽  
Hefang Bian ◽  
Bin Li ◽  
Weihua Bi ◽  
Xingtao Zhao
Keyword(s):  
Imaging System ◽  
Low Cost ◽  
3D Models ◽  
Digital Cameras ◽  
Typical Application ◽  
Textural Quality ◽  
Small Device ◽  
Aerial Vehicle ◽  
Automatic Capture ◽  
Imaging Sensor

Newly developed oblique photogrammetry (OP) techniques based on unmanned aerial vehicles (UAVs) equipped with multicamera imaging systems are widely used in many fields. Smartphones cost less than the cameras commonly used in the existing UAV OP system, providing high-resolution images from a built-in imaging sensor. In this paper, we design and implement a novel low-cost and ultralight UAV OP system based on smartphones. Firstly, five digital cameras and their accessories detached from the smartphones are then fitted into a very small device to synchronously shoot images at five different perspective angles. An independent automatic capture control system is also developed to realize this function. The proposed smartphone-based multicamera imaging system is then mounted on a modified version of an existing lightweight UAV platform to form a UAV OP system. Three typical application examples are then considered to evaluate the performance of this system through practical experiments. Our results indicate that both horizontal and vertical location accuracy of the generated 3D models in all three test applications achieve centimeter-level accuracy with respect to different ground sampling distances (GSDs) of 1.2 cm, 2.3 cm, and 3.1 cm. The accuracy of the two types of vector maps derived from the corresponding 3D models also meet the requirements set by the surveying and mapping standards. The textural quality reflected by the 3D models and digital ortho maps (DOMs) are also distinguishable and clearly represent the actual color of different ground objects. Our experimental results confirm the quality and accuracy of our system. Although flight efficiency and the accuracy of our designed UAV OP system are lower than that of the commercial versions, it provides several unique features including very low-cost, ultralightweight, and significantly easier operation and maintenance.

scholarly journals Modelling and Visualization of Three Dimensional Objects Using Inexpensive Digital Cameras

2018 ◽  
Author(s):  
Ismail Elkhrachy
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Point Clouds ◽  
3D Models ◽  
Bundle Adjustment ◽  
Control Points ◽  
Digital Cameras ◽  
Three Dimensional Objects ◽  
Spatial Positioning ◽  
And Control

This paper analyses and evaluate the precision and the accuracy the capability of low-cost terrestrial photogrammetry by using many digital cameras to construct a 3D model of an object. To obtain the goal, a building façade has imaged by two inexpensive digital cameras such as Canon and Pentax camera. Bundle adjustment and image processing calculated by using Agisoft PhotScan software. Several factors will be included during this study, different cameras, and control points. Many photogrammetric point clouds will be generated. Their accuracy will be compared with some natural control points which collected by the laser total station of the same building. The cloud to cloud distance will be computed for different comparison 3D models to investigate different variables. The practical field experiment showed a spatial positioning reported by the investigated technique was between 2-4cm in the 3D coordinates of a façade. This accuracy is optimistic since the captured images were processed without any control points.

Low-cost Photogrammetry for Culture Heritage

2017 ◽  
Author(s):  
Roman Shults ◽  
Petro Krelshtein ◽  
Iulia Kravchenko ◽  
Olga Rogoza ◽  
Oleksandr Kyselov
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
3D Models ◽  
Theory And Practice ◽  
Quality Data ◽  
Digital Cameras ◽  
High Quality ◽  
Culture Heritage ◽  
Practical Guidelines ◽  
Close Range

Culture heritage will always remain one of the priorities of any state. Taking a cultural or historical object under protection is impossible without inventory. The best technology, which allows getting high-quality inventory, is close-range photogrammetry. Unfortunately, the full capabilities of this technology is fully owned by professionals only. The situation changed significantly with the advent of mobile devices that are equipped with digital cameras and low-cost software that does not require any special knowledge in the theory and practice of photogrammetry. These developments have been called lowcost photogrammetry technologies. In the present study, we examined the use of smartphones and nano UAV and PhotoScan software for solve the problem fortifications II World War inventory near the city of Kiev. For qualitative data, the calibration of digital cameras in smartphones and ultra-light UAV was performed on calibration bench. One of the features of this project was the integration of the terrestrial photos and photos captured by nano UAVs. As a result of work performed were obtained 3D models of fortifications. Results showed high efficiency of the low-cost photogrammetry technologies. At the end of work some practical guidelines were provided, how to get high-quality data using low-cost photogrammetry technologies.

scholarly journals 3D LOW-COST ACQUISITION FOR THE KNOWLEDGE OF CULTURAL HERITAGE: THE CASE STUDY OF THE BUST OF SAN NICOLA DA TOLENTINO

2019 ◽  
Vol XLII-2/W17 ◽  
pp. 93-100
Author(s):  
A. Cardaci ◽  
A. Versaci ◽  
P. Azzola
Keyword(s):  
3D Reconstruction ◽  
Cultural Heritage ◽  
Low Cost ◽  
Three Dimensional ◽  
3D Models ◽  
Photographic Images ◽  
Reconstruction Software ◽  
Cultural Sphere ◽  
Three Dimensional Models

Abstract. The creation of three-dimensional models for the cataloguing and documentation of cultural heritage is today an emerging need in the cultural sphere and, above all, for museums. The cultural heritage is still catalogued and documented based on descriptive files assorted of photographic images which, however, fail to outline its spatial richness, possible only through the use of 3D artefacts. The essay aims to propose a methodology of digitalization by low-cost and easy-to-use systems, to be employed even by non-expert survey and photogrammetry’s operators. The case study of the statue of San Nicola da Tolentino, preserved at the Sant’Agostino complex in Bergamo, offered the possibility of a comparison between 3D models acquired with different digitalization tools (professional/action/amateur cameras and smartphone) and processed by several image-based 3D Reconstruction software and methods.

scholarly journals INITIAL EVALUATION OF 3D RECONSTRUCTION OF CLOSE OBJECTS WITH SMARTPHONE STEREO VISION

2018 ◽  
Vol XLII-1 ◽  
pp. 289-293 ◽  
Author(s):  
A. Masiero ◽  
F. Fissore ◽  
M. Piragnolo ◽  
A. Guarnieri ◽  
F. Pirotti ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Mobile Devices ◽  
Stereo Vision ◽  
Vision System ◽  
Focal Length ◽  
Low Cost ◽  
3D Models ◽  
Discrimination Ability ◽  
Depth Discrimination ◽  
Small Baseline

<p><strong>Abstract.</strong> The Worldwide spread of relatively low cost mobile devices embedded with dual rear cameras enables the possibility of exploiting smartphone stereo vision for producing 3D models. Despite such idea is quite attractive, the small baseline between the two cameras restricts the depth discrimination ability of this kind of stereo vision systems. This paper presents the results obtained with a smartphone stereo vision system by using two rear cameras with different focal length: this operating condition clearly reduces the matchable area. Nevertheless, 3D reconstruction is still possible and the obtained results are evaluated for several camera-object distances.</p>

scholarly journals THE USE OF THE UAV IMAGES FOR THE BUILDING 3D MODEL GENERATION

2018 ◽  
Vol XLII-4/W8 ◽  
pp. 217-223 ◽  
Author(s):  
G. Vacca ◽  
G. Furfaro ◽  
A. Dessì
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
3D Model ◽  
Low Cost ◽  
Laser Scanner ◽  
3D Models ◽  
Digital Cameras ◽  
Dense Matching ◽  
Uav Images ◽  
The University

<p><strong>Abstract.</strong> The growing interest in recent years in Unmanned Aerial Vehicles (UAVs) by the scientific community, software developers, and geomatics professionals, has led these systems to be used more and more widely, in different fields of engineering and architecture. This is thanks, above all, to their flexibility of use and low cost compared to traditional photogrammetric flights using expensive metric digital cameras or LiDAR sensors. In recent years, UAVs have also been used in the field of monitoring and inspection of public or private buildings that are remarkable in terms of size and architecture. This is mainly due to the focus a sustainability and resource efficiency in the building and infrastructure sector, which aims to extend their lifetimes. Through the use of remote checking using UAVs, the monitoring and inspection of buildings can be brought to a new level of quality and saving.</p><p> This paper focuses on the processing and study of 3D models obtained from images captured by an UAV. In particular, the authors wanted to study the accuracy gains achieved in the building 3D model obtained with both nadir and oblique UAV flights. The images from the flights were processed using Structure-for Motion-based approach for point cloud generation using dense image-matching algorithms implemented in an open source software. We used the open source software VisualSfM, developed by Chanchang Wu in collaboration with the University of Washington and Google. The dense matching plug-in integrated in its interface, PMVS/CMVS, made by Yasutaka Furukawa, was employed to generate the dense cloud. The achieved results were compare with those gained by Photoscan software by Agisoft and with 3D model from the Terrestrial Laser Scanner (TLS) survey.</p>

scholarly journals 3D Reconstruction of Exposed Underground Utilities Using Photogrammetric Methods

2021 ◽  
Author(s):  
Wensong Hu
Keyword(s):  
3D Reconstruction ◽  
Digital Images ◽  
Low Cost ◽  
Three Dimensional ◽  
Lookup Table ◽  
Image Point ◽  
Digital Cameras ◽  
Study Results ◽  
Underground Utilities ◽  
3D Information

This thesis addresses the topic of three-dimensional (3D) reconstruction of exposed underground utilities using photogrammetric methods. Research on this topic is mainly motivated by the need for improved information on the location of underground utilities and, thus, to provide reliable information for the management of buried assets. In this thesis, a system of photogrammetric software programs is developed for 3D reconstruction of underground utilities. Camera calibration programs are used for computing interior elements and lens distortion coefficients of digital cameras and saving them in a lookup table (LUT). The accuracy of calibrated image coordinates satisfies the photogrammetric processing demand. An automatic image point detection method is proposed and achieved in these programs. External orientation programs are used for calculating exterior elements of the digital images. Based on geographic information system (GIS) and global positioning system (GPS) techniques, a new ground control points (GCPs) collection method is proposed and implemented in these programs. A 3D reconstruction program provides corresponding functions to obtain and edit 3D information of underground utilities. Epipolar lines are employed as an assisting tool that helps operators easily find homologous points from different digital images. The study results indicate that photogrammetric methods for reconstructing 3D information of underground utilities are effective and low cost.

scholarly journals TOWARDS COMPLETE, GEO-REFERENCED 3D MODELS FROM CROWD-SOURCED AMATEUR IMAGES

2016 ◽  
Vol III-3 ◽  
pp. 51-58 ◽  
Author(s):  
W. Hartmann ◽  
M. Havlena ◽  
K. Schindler
Keyword(s):  
3D Reconstruction ◽  
Structure From Motion ◽  
Small Proportion ◽  
3D Models ◽  
Digital Cameras ◽  
Partial Reconstruction ◽  
Image Correspondence ◽  
Repetitive Structure ◽  
Architectural Models ◽  
The Individual

Despite a lot of recent research, photogrammetric reconstruction from crowd-sourced imagery is plagued by a number of recurrent problems. (i) The resulting models are chronically incomplete, because even touristic landmarks are photographed mostly from a few “canonical” viewpoints. (ii) Man-made constructions tend to exhibit repetitive structure and rotational symmetries, which lead to gross errors in the 3D reconstruction and aggravate the problem of incomplete reconstruction. (iii) The models are normally not geo-referenced. In this paper, we investigate the possibility of using sparse GNSS geo-tags from digital cameras to address these issues and push the boundaries of crowd-sourced photogrammetry. A small proportion of the images in Internet collections (&asymp;&thinsp;10&thinsp;%) do possess geo-tags. While the individual geo-tags are very inaccurate, they nevertheless can help to address the problems above. By providing approximate geo-reference for partial reconstructions they make it possible to fuse those pieces into more complete models; the capability to fuse partial reconstruction opens up the possibility to be more restrictive in the matching phase and avoid errors due to repetitive structure; and collectively, the redundant set of low-quality geo-tags can provide reasonably accurate absolute geo-reference. We show that even few, noisy geo-tags can help to improve architectural models, compared to puristic structure-from-motion only based on image correspondence.

scholarly journals La Torre della Marina di Vietri sulla Costa d’Amalfi: test statistico-predittivi di dati fotogrammetrici

X ◽  
2020 ◽  
Author(s):  
Sara Morena ◽  
Salvatore Barba
Keyword(s):  
Single Case ◽  
Low Cost ◽  
Relative Effectiveness ◽  
Three Dimensional ◽  
3D Models ◽  
Predictive Test ◽  
Historical Building ◽  
Starting Point ◽  
Propagation Law ◽  
The Individual

The Tower of Marina di Vietri on Amalfi Coast: a statistical-predictive test of photogrammetric dataThe focus of the work is on close-range photogrammetry and mainly on the low-cost technologies, experimented in the survey of Tower of Marina di Vietri, a historical building erected in the sixteenth century at Vietri sul Mare in the Province of Salerno. The general objective is to codify a methodology for objectifying the comparisons of the results; hence, the research starts from an original analysis conducted on the returned orthophotos by several photogrammetric paradigms. To estimate its reliability and precision, we proceeded, at first, with the extension and application of an error propagation law and then with the validation of the comparison according to a predictive type test. The first results are presented here after a study on raster images generated according to different algorithms. Subsequently, on each graphic product, 73 points were identified and for each of the relative coordinates the deviation are evaluated by verifying them with the value of the standard deviation. Consequently, for the purpose of greater validation of the methodology, a predictive test was implemented with the aim to confirm the criterion used for the comparison and to guarantee, in probabilistic terms, the values analysed; finally, a further three-dimensional analysis was conducted directly on the 3D models. It is banal to observe that aleatory –subjectivity, etc.– which often characterizes already known approaches, in any case assumed as a starting point, does not always allow to obtain generally valid results and, therefore, extendable beyond the single case study. The implementation of this first test, otherwise, proved to be extremely valid in the survey for architecture, both for an absolute evaluation of the quality of the individual results and for the possibility to estimate, also predictively, the relative effectiveness of the method used. This guarantees the evaluation of the relative percentages of errors in probabilistic terms.

scholarly journals 3D Reconstruction of Exposed Underground Utilities Using Photogrammetric Methods

2021 ◽  
Author(s):  
Wensong Hu
Keyword(s):  
3D Reconstruction ◽  
Digital Images ◽  
Low Cost ◽  
Three Dimensional ◽  
Lookup Table ◽  
Image Point ◽  
Digital Cameras ◽  
Study Results ◽  
Underground Utilities ◽  
3D Information

This thesis addresses the topic of three-dimensional (3D) reconstruction of exposed underground utilities using photogrammetric methods. Research on this topic is mainly motivated by the need for improved information on the location of underground utilities and, thus, to provide reliable information for the management of buried assets. In this thesis, a system of photogrammetric software programs is developed for 3D reconstruction of underground utilities. Camera calibration programs are used for computing interior elements and lens distortion coefficients of digital cameras and saving them in a lookup table (LUT). The accuracy of calibrated image coordinates satisfies the photogrammetric processing demand. An automatic image point detection method is proposed and achieved in these programs. External orientation programs are used for calculating exterior elements of the digital images. Based on geographic information system (GIS) and global positioning system (GPS) techniques, a new ground control points (GCPs) collection method is proposed and implemented in these programs. A 3D reconstruction program provides corresponding functions to obtain and edit 3D information of underground utilities. Epipolar lines are employed as an assisting tool that helps operators easily find homologous points from different digital images. The study results indicate that photogrammetric methods for reconstructing 3D information of underground utilities are effective and low cost.

Sign in / Sign up

Export Citation Format

Share Document