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Refractive Geometry for Underwater Domes [article]

Mengkun She, David Nakath, Yifan Song, Kevin Köser
2021 arXiv   pre-print
We show that the overall camera system becomes an axial camera, even for thick domes as used for deep sea exploration and provide a non-iterative way to compute the center of refraction without requiring  ...  Spherical glass, a dome port, is well suited for high water pressures at great depth, allows for a large field of view, and avoids refraction if a pinhole camera is positioned exactly at the sphere's center  ...  Amit Agrawal for offering generous help when deriving the analytical forward projection for the thin dome model. The authors also would like to thank Mareike Kampmeier for providing the AUV  ... 
arXiv:2108.06575v2 fatcat:usucbeoz4rdkjfe5qhkjqh3lei

An Optical Digital Twin for Underwater Photogrammetry

David Nakath, Mengkun She, Yifan Song, Kevin Köser
2022 PFG – Journal of Photogrammetry Remote Sensing and Geoinformation Science  
Commonly, a flat window or a half-sphere of glass, called flat-port or dome-port, respectively is used to implement such kind of interface.  ...  AbstractMost parts of the Earth's surface are situated in the deep ocean. To explore this visually rather adversarial environment with cameras, they have to be protected by pressure housings.  ...  We are also grateful for support from the Chinese Scholarship Council (CSC) for M. She (202006050015).  ... 
doi:10.1007/s41064-021-00190-9 fatcat:2bax4v733zhfva374cbsygo5pq

Portable polarimetric underwater imaging system with a linear response

Nir Karpel, Yoav Y. Schechner, Dennis H. Goldstein, David B. Chenault
2004 Polarization: Measurement, Analysis, and Remote Sensing VI  
We aim to utilize this phenomenon in a new generation of underwater imaging systems in order to partially compensate for the loss of color and visibility.  ...  In order to obtain quantitative measurement of radiance and polarization, the imaging system should have a linear radiometric response and low noise.  ...  ACKNOWLEDGMENTS We are grateful to Yoav Fhiler for enabling the use of the Technion's swimming pool in preliminary experiments. We also wish to thank Naftalli Blau for his help in scuba dives.  ... 
doi:10.1117/12.542484 fatcat:tqvgs2pgxncmtpuydg3o6wiahy

ON SCALE DEFINITION WITHIN CALIBRATION OF MULTI-CAMERA SYSTEMS IN MULTIMEDIA PHOTOGRAMMETRY

O. Kahmen, R. Rofallski, N. Conen, T. Luhmann
2019 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
</strong> In multimedia photogrammetry, multi-camera systems often provide scale by a calibrated relative orientation.  ...  Camera calibration via bundle adjustment is a well-established standard procedure in single-medium photogrammetry.  ...  ACKNOWLEDGEMENT This work is based on three projects, funded by the European Regional Development Fund (EFRE, ZW 6-85003503 and 6-85007826) and by the Volkswagen Foundation, Germany (ZN3253).  ... 
doi:10.5194/isprs-archives-xlii-2-w10-93-2019 fatcat:z7klx42jkngcpfy7o3oupfk4kq

Perspective and Non-perspective Camera Models in Underwater Imaging – Overview and Error Analysis [chapter]

Anne Sedlazeck, Reinhard Koch
2012 Lecture Notes in Computer Science  
to compensate for the error induced by refraction at the camera housing.  ...  Secondly, the glass interface between air and water refracts the ray entering the camera housing because of a different index of refraction of water, hence the ray is also affected in a geometrical way  ...  In [27] , the usage of a perspective camera in an underwater scenario is examined as well as a flat port and dome port model.  ... 
doi:10.1007/978-3-642-34091-8_10 fatcat:fwcvmohiargylkhmnozyywez5q

Impact of Stereo Camera Calibration to Object Accuracy in Multimedia Photogrammetry

Oliver Kahmen, Robin Rofallski, Thomas Luhmann
2020 Remote Sensing  
Camera calibration via bundle adjustment is a well-established standard procedure in single-medium photogrammetry.  ...  Explicit modelling of the refractive interfaces is implemented into a bundle adjustment and is also used to analyse calibration parameters and deviations in object space.  ...  The separation is made between a single-camera and a multi-camera system and between hemispherical (dome) and flat port.  ... 
doi:10.3390/rs12122057 fatcat:bs7f5664orhzdikucjbdnagmz4

Image-Based Underwater 3D Reconstruction for Cultural Heritage: From Image Collection to 3D. Critical Steps and Considerations [chapter]

Dimitrios Skarlatos, Panagiotis Agrafiotis
2020 Springer Series on Cultural Computing  
algorithms to Structure from Motion (SfM) and Multi-View Stereo (MVS) techniques to produce an accurate, precise and complete 3D model for a number of applications.  ...  This chapter dis-cusses critical aspects of all phases of image based underwater 3D reconstruc-tion process, from data acquisition and data preparation using colour restora-tion and colour enhancement  ...  Demesticha for providing data from several underwater sites, and moreover challenging the authors to overcome problems and shortcomings of the 3D documentation process in underwater CH.  ... 
doi:10.1007/978-3-030-37191-3_8 fatcat:xd6jun7ihrhdpdnpmj3ldele5y

Underwater robotic system for reservoir maintenance

Piotr Kohut, Mariusz Giergiel, Patryk Cieslak, Michal Ciszewski, Tomasz Buratowski
2016 Journal of Vibroengineering  
Robots' design, mathematical models of kinematics and dynamics of the crawler robot, ROV's vision system architecture with image processing methods for surface crack detection and robot position and attitude  ...  His research interests focus on nonlinear modelling, dynamical simulation and control system design for various types of robots, especially underactuated, unstable and redundant, including underwater vehicle-manipulator  ...  R03005710 "Mechatronic Designing of Robots for Diagnostics and Maintenance of Tanks with Liquid".  ... 
doi:10.21595/jve.2016.17364 fatcat:3rzdf7zwpvbdrnfelgpuxkb3t4

Camera Calibration for Underwater 3D Reconstruction Based on Ray Tracing Using Snell's Law

Malte Pedersen, Stefan Hein Bengtson, Rikke Gade, Niels Madsen, Thomas B. Moeslund
2018 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition Workshops (CVPRW)  
The precision of the estimated 3D positions based on the underwater camera calibration and the ray tracing based approach were, on the other hand, almost identical.  ...  Three ways of performing 3D reconstruction on underwater objects are compared in this work: an approach relying solely on in-air camera calibration, an approach with the camera calibration performed under  ...  The latter also tries to account for the problem of refraction by mounting a dome port instead of a flat port in front of the camera.  ... 
doi:10.1109/cvprw.2018.00190 dblp:conf/cvpr/PedersenBGMM18 fatcat:rrhb74grwvax3lpfxxwcixiuhu

EVALUATION OF VISION-BASED LOCALIZATION AND MAPPING TECHNIQUES IN A SUBSEA METROLOGY SCENARIO

F. Menna, A. Torresani, E. Nocerino, M. M. Nawaf, J. Seinturier, F. Remondino, P. Drap, B. Chemisky
2019 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In this study, the authors investigate the use of state-of-art vision-based algorithms, i.e.  ...  In particular, the manuscript will focus on methods for assessing the accuracy of both trajectory and tie points provided by the tested approaches and evaluating whether the preliminary real time reconstruction  ...  The version tested in this study is the 3Kv rated to a depth of 3000m with camera pressure housings made of titanium and dome ports made of optical glass.  ... 
doi:10.5194/isprs-archives-xlii-2-w10-127-2019 fatcat:b3sbyuet3zg2ndh3ujqen4ccsy

Laser And Vision-Based Obstacle Avoidance For A Semi-Autonomous ROV

2019 Advanced Materials Proceedings  
Remotely operated vehicles (ROV) and Autonomous underwater vehicles (AUV) are increasingly being used for a large spectrum of maritime tasks for which human intervention is either dangerous or impossible  ...  In order for the ROV to take control, a C++ software was developed to receive ROV sensors data, process it and send commands using the same serial communications port the operator uses.  ...  Author's contributions Designed the Laser-based sensor: Developed a Matlab set of programs that calibrate the ROV camera and measures distances to obstacles; Developed a C++ program that interfers with  ... 
doi:10.5185/amp2019.1459 fatcat:q7a5442mezanfejaldopx4ls6a

Laser and Vision-Based Obstacle Avoidance for A Semi-Autonomous ROV

Gil Silva
2020 Advanced Materials Proceedings  
Remotely operated vehicles (ROV) and Autonomous underwater vehicles (AUV) are increasingly being used for a large spectrum of maritime tasks for which human intervention is either dangerous or impossible  ...  In order for the ROV to take control, a C++ software was developed to receive ROV sensors data, process it and send commands using the same serial communications port the operator uses.  ...  Acknowledgements This work was supported by IEETA -Institute of Electronics and Informatics Engineering of Aveiro, University of Aveiro, Portugal..  ... 
doi:10.5185/amp.2019.1459 fatcat:pjzzpsekljf4xjcwlcgwlbbxti

ITERATIVE REFINEMENT FOR UNDERWATER 3D RECONSTRUCTION: APPLICATION TO DISPOSED UNDERWATER MUNITIONS IN THE BALTIC SEA

Y. Song, K. Köser, T. Kwasnitschka, R. Koch
2019 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
</strong> With the rapid development and availability of underwater imaging technologies, underwater visual recording is widely used for a variety of tasks.  ...  At the end, this paper also shows its application results for 3D reconstruction of a dump site for underwater munition in the Baltic Sea for which a visual monitoring approach is desired.</p>  ...  The authors would also like to thank Mareike Kampmeier and the scientific divers for capturing the underwater image materials.  ... 
doi:10.5194/isprs-archives-xlii-2-w10-181-2019 fatcat:r4nlm2bse5dthlydfcrrn3hlei

IMAGE PRE-PROCESSING STRATEGIES FOR ENHANCING PHOTOGRAMMETRIC 3D RECONSTRUCTION OF UNDERWATER SHIPWRECK DATASETS

A. Calantropio, F. Chiabrando, B. Seymour, E. Kovacs, E. Lo, D. Rissolo
2020 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
This article focuses on the 3D model generation of underwater shipwrecks and intends explicitly to address the problem of dealing with sub-optimal datasets.  ...  This work focuses on the investigation of different strategies and approaches for balancing the quality of the photogrammetric products, without neglecting their reliability concerning the surveyed object  ...  ACKNOWLEDGEMENTS The authors would like to thank the Submerged Resources Center (SRC) of the US National Park Service (NPS), under the direction of Dave Conlin, for their availability and support in carrying  ... 
doi:10.5194/isprs-archives-xliii-b2-2020-941-2020 fatcat:7ffdnsog7vatlarq5t3rzbhw2e

Deep Sea Bubble Stream Characterization Using Wide-Baseline Stereo Photogrammetry [article]

Mengkun She, Yifan Song, Tim Weiß, Jens Greinert, Kevin Köser
2021 arXiv   pre-print
The dedicated instrument employs a high-speed deep sea stereo camera system that can record terabytes of bubble imagery when deployed at a seep site for later automated analysis.  ...  Beside reporting the steps to make bubble characterization robust and autonomous, we carefully evaluate the reachable accuracy and propose a novel calibration procedure that, due to the lack of point correspondences  ...  Acknowledgments The authors would like to thank Matthias Wieck, Jan Sticklus, Eduard Fabrizius and Thorsten Schott for co-designing and constructing the many components of the systems.  ... 
arXiv:2112.07414v2 fatcat:kjfycxm2gbhlndsclokdyxa7ae
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