@inproceedings{article,

title = {5dMeteora: Information System for Multi-Level Documentation of Religious Sites and Historic Complexes},

author = {Charalabos Ioannidis and Sofia Soile and Argyro Βoutsi and Styliani Verykokou and Panagiotis Tokmakidis and Konstantinos Tokmakidis and Chryssy Potsiou},

url = {https://www.fig.net/resources/proceedings/fig_proceedings/fig2022/papers/ts01e/TS01E_ioannidis_soile_et_al_11447.pdf},

year  = {2022},

date = {2022-09-01},

urldate = {2022-09-01},

booktitle = {FIG Congress 2022: Volunteering for the future - Geospatial excellence for a better living},

abstract = {This paper presents the work conducted in the context of the ongoing research project “Information System for Multi-Level Documentation of Religious Sites and Historic Complexes: METEORA” (http://meteora.topo.auth.gr/). The aim of this project is the creation of a web-based platform for the organization, management, visualization and dissemination of the products of the multi-level documentation of the UNESCO site of Meteora, Greece, with emphasis on two inaccessible huge rocks in the Meteora site: the rock of St. Modestos, known as Modi, and the Alyssos rock. The platform, named 5dMeteora, integrates a 3D viewer based on the 3DHOP (3D Heritage Online Presenter) framework, personalized information access and interactive tools for virtual navigation, immersion, data retrieval and presentation. Both spatial data (high-resolution textured 3D models generated through combination of photogrammetric and surveying techniques) and non-spatial data (textual information, images and videos) related to historical, religious, cultural, architectural and geopolitical aspects of the two rocks of interest and the other monuments of the Meteora Archaeological Site are integrated in the platform. The content as well as the interactive services of the 5dMeteora platform are differentiated based on the scientific specialty and the field of interest of its users, serving their different requirements, based on properly structured scenarios of use, i.e., (i) tourists / simple users; (ii) geospatial engineers; (iii) archaeologists / architects / conservators; (iv) historians / philologists / theologians / priests; (v) educators; (vi) business entrepreneurs; and (vi) cultural heritage authorities. The 5dMeteora platform integrates an administrator interface for creating, updating and maintaining the functionalities of 3DHOP and customizing information based on the scientific specialty and field of interest of the users, offering automation in authoring, managing, uploading and updating 2D and 3D content and creating clickable points of interest on top of the surfaces of 3D models.},

keywords = {3D modelling, 3D viewer, Cultural heritage, Information System, visualization},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Lourakis_2021_ICCV,

title = {Markerless Visual Tracking of a Container Crane Spreader},

author = {Manolis Lourakis and Maria Pateraki},

year  = {2021},

date = {2021-10-01},

urldate = {2021-10-01},

booktitle = {Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV) Workshops},

pages = {2579-2586},

abstract = {Crane systems play a crucial role in container transport logistics. This paper presents an approach for visually tracking the position and orientation in 3D space of a container crane spreader. An initial pose estimate is first employed to render a 3D triangle mesh model of the spreader as a wireframe with hidden lines removed. The initial pose is then refined so that the visible lines of the wireframe match the straight line segments detected in an input image. Line segment matching relies on fast, local one-dimensional searches along a segment’s normal direction. Matched line segments yield constraints on the spreader motion which are processed with robust parameter estimation techniques that safeguard against outliers stemming from mismatches. The tracker automatically determines the visibility of segments, without making limiting assumptions regarding the spreader’s 3D mesh model. It is also robust to parts of the tracked spreader being out of view, occluded, shadowed or simply undetected. Experimental results demonstrating the tracker’s performance are additionally included.},

keywords = {Cranes, Image segmentation, Motion segmentation, Solid modeling, Three-dimensional displays, Tracking, visualization},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{Ioannidis2021,

title = {From 3D documentation to XR representation of Cultural Heritage buildings -The case of the Katholikon of St. Stephen, Meteora},

author = {Charalabos Ioannidis and Sofia Soile and Argyro-maria Boutsi and Styliani Verykokou and Fotios Bourexis and Chryssy Potsiou},

url = {https://fig.net/resources/proceedings/fig_proceedings/fig2021/papers/ts03.2/TS03.2_ioannidis_soile_et_al_11027.pdf},

year  = {2021},

date = {2021-01-01},

urldate = {2021-01-01},

booktitle = {FIG e-Working Week 2021, Smart Surveyors for Land and Water Management},

number = {June},

abstract = {Photogrammetric surveying and 3D modelling are of immense value for the diagnosis and conservation of historic and religious buildings. In case they are coupled with eXtended Reality (XR) technologies (i.e., Virtual, Augmented and Mixed Reality), different levels of interpretation, interaction and dissemination can be achieved. This paper presents a holistic approach to the multi-representation of the restoration phases of a Byzantine church. The aim is twofold; the introduction of a low-cost photogrammetric methodology for a detailed and accurate 3D geometric documentation of CH buildings, and the development of a web-based integrated 3D platform with XR functionalities. The proposed methodology is applied to the external and internal 3D reconstruction of the 16 th century old church (Katholikon) of St. Stephen's Monastery in Meteora, Greece, at two different periods: prior and after church maintenance work and restoration innervations. Close-range photogrammetry and computer vision are used for the collection of image data and the generation of dense point clouds, surface models and texture mapping. The final 3D models along with their supported metadata are integrated into an online XR viewer for a comparative temporal analysis through an immersive experience. The viewer has the following capabilities: (i) automated virtual tour on the 3D scene, (ii) points of interest, (iii) VR navigation as well as, (iv) marker-less AR based on hand pattern recognition. The 3D rendering and progressive loading, the interactive tools as well as the various visualization modes are built upon Three.js, Tween.js and AR.js libraries. The evaluation of the developed platform regarding performance and usability demonstrates the effectiveness of VR and AR in remote access, monitoring and preservation of tangible Cultural Heritage.},

keywords = {3D modelling, AR, Cultural heritage, Photogrammetry, visualization, VR},

pubstate = {published},

tppubtype = {inproceedings}

}