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Smart Eye is a research project focused on developing and operating, in real-time, an innovative system, that allows the visualization of invisible, known, covered by the ground or by constructions, monuments and finds in an archaeological site, using an Augmented Reality (AR) environment. The visitors of an archaeological site will be able to observe the covered antiquities (3D models and descriptive information) on the screen of their mobile device (smart phone and/or tablet). The system integrates mobile positioning and pose estimation technologies, AR algorithms, Geographic Information Systems (GIS) and spatial databases. The AR application is implemented by IT scientists and is subsequently evaluated in the field to identify both technical problems (e.g. are files uploaded at high speed?) and problems identified by the average user of the AR application (e.g. would it be better if the button to display the 3D model of the archaeological excavation was larger on the screen or of a different color?). The paper will present, on one hand, the validation and evaluation protocols according to the relevant literature, and on the other, the exact evaluation methodology of the Smart Eye system. In addition, the problems identified and the way they were solved during the 1st evaluation of the application will be presented, as well as the problems identified during the 2nd evaluation.

DIGI-ORCH is a research project with objectives, on one hand, to design and develop "smart" brochures for concerts and educational programs of the State Conservatory of Thessaloniki (Greece), and, on the other, to develop an innovative system for the visualization of information on smart mobile devices (smartphones and tablets). The application of Augmented Reality (AR) provides free access to the information and content of the above concerts and educational programs, combining the information of a robust data server and an easy-to-use user interface of the smart device in real-time.The pilot implementation of the system in real conditions took place at the beginning of December 2022, in an event held at the facilities of the State Conservatory of Thessaloniki. The event was an evening of Chamber Music entitled Musical Kaleidoscope, with the internationally acclaimed artists Simos Papanas (violin), Dimos Goundaroulis (violoncello), and Vassilis Varvaresos (piano). They performed the Piano Trio no. 3 in G minor, Robert Schumann's opus 110, and the Piano Trio no. 2 in E flat major, Op. 100 D. 929 by Franz Schubert. The concert was attended by over 150 attendees.The paper will present the chaîne-operatoire of the development of the system, from the acquisition of raw data (text, video, image, and sound) to the methodology used to produce the "smart" event brochure and the AR application for the above concert. Essentially, this large amount of information that cannot be assessed by a regular printed concert brochure is included in the smart system and displayed on the mobile device when the user locates the appropriate AR patterns on the surface of the analog concert poster and/or on the pages of the brochure.This information comprised of ie. additional text and images about the composers and their musical projects, about the musicians of the concert (e.g. biographies), their interviews and rehearsals (video) before the concert, information about the State Conservatory of Thessaloniki (text, video, image, and sound), 3D models of musical instruments, 360° of the concert space, etc. diverse multimedia material.

Although there are several attempts of embedding static content in events’ brochures and posters, the increasing need for flexibility and versatility of the content, leads to the development of a mobile application with an in-app dynamic content management system. In this context, DigiOrch is an ongoing research program where, a Content Management System is developed to organize all the digital material and maintain the appropriate connection to the analogical markers. Furthermore, a mobile application is developed that lev-erages this system using in app dynamic modules, which, by utilizing the augmented reality technology, presents multimedia data such as texts, photos, videos, and 3D Models to the end-user by “superimposing” them on mobile devices screen, providing extra additional information on any valid smart-leaflet.The overall workflow of the in-app Dynamic Content Management System (DCMS) can be described as a group of modules that managing and copying content files from a remote infrastructure such as an ftp server or a local resource if network is missing, to the mobile device’s file system.The in-app DCMS consists of 4 modules: The first module is the parser, which is responsible for reading a downloaded *.json file and creating content-linked objects. The second module is the download module which is responsible for downloading the overall content by iterating the content-linked objects, created by the previous module. The third module le is the update module that, by iterating the initial content file and the local file system, suggests whether a content update is necessary. The fourth module is the loading module, which is responsible for fetching the content on runtime to fill the content-holding components, such as 3D Models and UI photo galleries, of the AR scenes on runtime.

Augmented Reality/Virtual Reality (AR/VR) technology offers novel and excited experiences to visitors of cultural sites. Extended recent technological advances in smart communication devices made the connection of the real to the virtual worlds more affordable and effective. In spite of the rapid development and availability of the AR/VR applications to cultural heritage, there still exist gaps and challenges in accurate positioning and navigation of visitors’ smart devices in both out-doors archaeological spaces as well as in in-doors museum spaces. Recent technology smart devices embody GNSS positioning sensors, which in best cases, provide 1-meter positioning accuracies in open spaces, while are unable to work in-doors. Such accuracies and restrictions lead to gaps in fetching visitor’s position in AR environments and mis-positions with regard to the rest AR/VR objects as visualized in smart screens, while the problem gets worse when dealing with real-time videoing, when elapse times and refresh rates lead to additional mispositionings. In this paper, effort is made to present and evaluate the most recent and widely used tools for positioning and navigation of smart devices in in- and out-doors CH sites.

The use of Augmented Reality (AR) technology is widespread in countless archaeological sites and a variety of applications. Archaeological excavations lead to archaeological finds, some of which are transported for preservation and then for exhibition in museums (jewelry, vases, etc.), while another part of them is documented in detail and remains in situ (eg building walls), roads, grave covers, etc.). However, after the registration of the archaeological finds, it is impossible to observe them. As part of our research project, we will develop for the first time AR methodology and procedures for the observation of covered archaeological finds on mobile devices (smart phones, tablets), which were registered after their documentation. AR technology in recent years has seen great growth in terms of implementation platforms and available software, as well as the tools developed to support it. These tools either make their appearance in the form of frameworks, extending the capabilities of an existing engine, or function as independent services. At the same time, progress has been made in the field of sensors of mobile devices, which makes the compatibility of hardware and software another issue to be researched. As part of the development of the above application for mobile devices, an evaluation is made of the most widespread AR Frameworks that support the Unity3d Game Engine and the compatibility / interoperability with the sensors of different categories of mobile devices. The frameworks were checked and evaluated for placement and tracking of the positions of the 3D covered objects. In this paper also, methodologies and techniques used in space detection and tracking are presented and evaluated.

Nowadays, there are many methods and techniques for the documentation and the restoration of historic structures and historical artifacts that are commonly used due to their completeness, accuracy and fastness. The use of advanced 3D measurement technologies, by either using terrestrial or aerial means of acquiring digital data, has become an efficient and reliable documentation tool. Within this context, this study focuses on combining terrestrial laser scanning, unmanned aerial vehicle photogrammetry, close-range photogrammetry and topographic surveying, and comparing the associated digital data for archaeological fieldwork documentation. The data collected during the Thessaloniki Toumba Excavation (Greece) provided accurate digital surface models and photo-realistic three-dimensional outputs of archaeological trenches. The data elaboration enabled new inferences and knowledge to be gained through the implementation of advanced technologies in heritage documentation.

In recent years advances in Earth Observation (EO) have increased our ability to inventory, monitor, and understand Earth’s natural and artificial ecosystems. In particular, recent technological developments in the instrument characteristics of the remote sensing systems enabled large-scale usage of EO in environmental governance and protection. Remote sensing can be a potent tool employed in the field of environmental compliance. However, to extract and distribute relevant information to potential stakeholders, simple, yet efficient and robust approaches are needed. The focus of our research is the development of EO algorithms and the corresponding EO processing chains that could be used operationally for providing cost-efficient information to end-users to address environmental compliance and tackle environmental violations over specific thematic domains using freely available Copernicus data. The EO algorithms and the relevant EO processing chains have been developed as part of the EU-H2020 funded project: “EnviroLENS-Copernicus for environmental law enforcement support” where the demonstration area of our approach is in the Montenegro – Albania border. The case considers several sites along the border to Albania, from the coastal area of Velika Plaža to the North Lake Skadar National Park. All sites have been designated in the past as protected areas, due to their rich biodiversity and threatened habitats. The focus of this contribution is on the deforestation detection processing chain. The developed EO processing chains rely on the use and analysis of multi-temporal Sentinel-2 images, while it adopts an object-based perspective for detecting, quantifying, and mapping potential environmental violations.

Land abandonment and secondary forest succession have played a significant role in land cover changes and forest cover increase in mountain areas in Europe over the past several decades. Land abandonment can be easily observed in the field over small areas, but it is difficult to map over the large areas, e.g., with remote sensing, due to its subtle and spatially dispersed character. Our previous paper presented how the LiDAR (Light Detection and Ranging) and topographic data were used to detect secondary forest succession on abandoned land in one commune located in the Polish Carpathians by means of object-based image analysis (OBIA) and GIS (Kolecka et al., 2015). This paper proposes how the method can be applied to efficiently map secondary forest succession over the entire Polish Carpathians, incorporating spatial sampling strategy supported by various ancillary data. Here we discuss the methods of spatial sampling, its limitations and results in the context of future secondary forest succession modelling.

Remote sensing facilitates the extraction of information for earth’s surface through its capability of acquiring images covering large areas and the availability of commercial software for their processing. The aim of this study is the feature extraction from three Geoeye-1 stereo pairs for forested area. The study area is located in central mountainous forested peninsula of Chalkidiki, in northern Greece. Dominant forest tree species of the site are oak (Quercus conferta), beech (Fagus moesiaca), black pine (Pinus nigra) and calabrian pine (Pinus brutia). Very High Resolution (VHR) Geoeye-1 stereo pair satellite images were utilized in panchromatic and multispectral mode. The panchromatic mode was employed for Digital Surface Model (DSM) generation and its evaluation. In this study the High Pass Filter (HPF) data fusion technique was applied between panchromatic and multispectral mode for acquiring a new image with the benefits of both contracting images. Because of the fact that the feature extraction was attempted in a forested region, NDVI index and Tasseled Cap transformation were applied in the fused images’ evaluation procedure. Optical assessment was also applied. The accuracy of the generated DSM and the evaluation results of the fused images were remarkable.

Virtual reality (VR) is extensively used in various applications; in industry, in academia, in business, and is becoming more and more affordable for end users from the financial point of view. At the same time, in academia and higher education more and more applications are developed, like in medicine, engineering, etc. and students are inquiring to be well-prepared for their professional life after their educational life cycle. Moreover, VR is providing the benefits having the possibility to improve skills but also to understand space as well. This paper presents the methodology used during a course, namely "Geoinformatics applications" at the School of Spatial Planning and Development (Eng.), Aristotle University of Thessaloniki, to create a virtual School space. The course design focuses on the methods and techniques to be used in order to develop the virtual environment. In addition the project aspires to become more and more effective for the students and provide a real virtual environment with useful information not only for the students but also for any citizen interested in the academic life at the School.

Photogrammetrey has a long successful history in the area of 3D modelling and documentation of cultural heritage monuments. In some cases an extensive study, preparation and the application of novel solutions is required for the successful documentation and 3D modelling of monuments. In most of the cases the problem that we have to face is difficulties regarding accessing, photographing, and measuring the monument from the optimal distance, in combination with the need for a high spatial resolution mapping. This paper is highlighting the special problems and the novel solutions, performed during mapping of two significant cultural heritage monuments in Greece. The Roussanou monastery (1527–1529 A.C., Meteora, Center Greece) and its underlying rock, had to be photographed and measured from a far distance and measured with various spatial resolutions. In the lakeside Neolithic settlement of Dispilio (6.000 B.C., western Greece) the enclosure which is covered with vegetation above a height of 3 m, had to be measured with high spatial resolution. The combined use of a laser scanner, a digital camera equipped with a telephoto lens and UAV allowed the successful mapping and the production of orthophotomaps in each case.