| 1. |
- Menna, Fabio, et al.
(författare)
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Improving Underwater Accuracy by Empirical Weighting of Image Observations
- 2018
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Ingår i: ISPRS Technical Commission II Symposium 2018. - : ISPRS. ; , s. 699-705
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Konferensbidrag (refereegranskat)abstract
- An underwater imaging system with camera and lens behind a flat port does not behave as a standard pinhole camera with additional parameters. Indeed, whenever the entrance pupil of the lens is not in contact with the flat port, the standard photogrammetric model is not suited anymore and an extended mathematical model that considers the different media would be required. Therefore, when dealing with flat ports, the use of the classic photogrammetric formulation represents a simplification of the image formation phenomenon, clearly causing a degradation in accuracy. Furthermore, flat ports significantly change the characteristics of the enclosed imaging device and negatively affect the image quality, introducing heavy curvilinear distortions and optical aberrations. With the aim of mitigating the effect of systematic errors introduced by a combination of (i) image quality degradation, induced by the flat ports, and (ii) a non-rigorous modelling of refraction, this paper presents a stochastic model for image observations that penalises those that are more affected by aberrations and departure from the pinhole model. Experiments were carried out at sea and in pools showing that the use of the proposed stochastic model is beneficial for the final accuracy with improvements up to 50 %.
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| 2. |
- Dell'Unto, Nicolo, et al.
(författare)
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The Use of 3D Models for Intra-Site Investigation in Archaeology
- 2014
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Ingår i: 3D Recording and Modeling in Archaeology and Cultural Heritage : theory and best practices - theory and best practices. - 9781407312309 ; :2598
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Bokkapitel (refereegranskat)abstract
- In recent decades, the development of technology that aids in documenting, analysing and communicating information regarding archaeological sites has affected the way that historical information is transmitted and perceived by the community. Digital technologies have affected archaeology at all levels; for example, novel investigation methods have highlighted new and unknown aspects of archaeological research. The constant development of friendly user-interfaces has encouraged the diffusion of and experimentation with different approaches. This article discusses how the use of three-dimensional models has changed our perception of field practices in archaeology. Specifically, this paper presents several experiments in which three-dimensional replicas of archaeological contexts were processed and used to document and monitor the short lifetime of on-going archaeological excavations. These case studies demonstrate how the use of digital technologies during field activities allows archaeological researchers to time-travel through their work to revisit contexts and material that had been previously removed during the investigation process.
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| 3. |
- Remondino, Fabio, et al.
(författare)
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Photogrammetric calibration of image sequences acquired with a rotating camera
- 2004
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Ingår i: Panoramic photogrammetry workshop. - : ISPRS.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper reports theory and examples about the calibration and orientation of fixed but freely rotating cameras with possible changes of the interior parameters. We consider cameras that are generally rotating, without any special adapter to remove the eccentricity between perspective center and rotation axis. That is the typical case of surveillance cameras or sport videos. Projective and perspective camera model are analyzed and between the reported examples, self-acquired images and old monocular videos of sports events are considered. We also show the possibility to achieve 3D object reconstruction using rotating cameras. Finally we will report the mosaic generation from images acquired with a rotating system.
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| 4. |
- Richards-Rissetto, Heather, et al.
(författare)
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Kinect and 3D GIS in archaeology
- 2012
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Ingår i: 18th international conference on virtual systems and multimedia. - : IEEE. - 9781467325646 - 9781467325639 ; , s. 331-337
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Konferensbidrag (refereegranskat)abstract
- This paper explores the potential of using Microsoft's Kinect to create a low-cost and portable system to virtually navigate, through a prototype 3D GIS, the digitally reconstructed ancient Maya city and UNESCO World Heritage Site of Copan in Honduras. The 3D GIS, named QueryArch3D, was developed as part of the MayaArch3D project (http://mayaarch3d.unm.edu), which explores the possibilities of integrating databases and 3D digital tools for research and teaching on ancient architectures and landscapes. The developed system, based on the Flexible Action and Articulated Skeleton Toolkit (FAAST), controls in a remote and touchless mode the movements in the 3D environment in order to create a sense of spatial awareness and embodiment. A user can thus use gestures to interact with information stored in the spatial database, calling up photos, videos, textual descriptions as he/she moves through the virtual space of the ancient Maya city.
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