Close-range Photogrammetry

Almásfüzitő római kori tábora Magyarország egyik legjobban megőrződött ilyen jellegű lelőhelye volt mindaddig, amíg a timföldgyártáshoz kapcsolódó vörösiszap tároló (VII. kazetta), a maradványokat elpusztítva meg nem épült. A kisebb volumenű régészeti kutatásokon kívül csupán a korabeli távérzékelési adatokra támaszkodhatunk a lelőhely kutatásával kapcsolatban, melyben hatalmas előrelépést jelentett, hogy a fényképalapú 3D modellezésnek köszönhetően tanulmányozhatjuk a megsemmisített nyomokat.

The advent of the smartphones brought with them higher processing capabilities and improved camera specifications which boosted the applications of mobile-based imagery in a range of domains. One of them is the 3-D reconstruction of objects by means of photogrammetry, which now enjoys great popularity. This fact brings potential opportunities to develop educational procedures in high schools using smartphone-based 3-D scanning techniques. On this basis, we designed a Project Based e-Learning (PBeL) initiative to introduce secondary students to the disciplines of photogrammetry through the use of their mobile phones in an attractive and challenging way for them. The paper describes the motivation behind the project "D3MOBILE Metrology World League", supported by ISPRS as part of the "Educational and Capacity Building Initiative 2020" programme. With this Science, Technology, Engineering and Mathematics (STEM) initiative, we implement a methodology with the format of an international competition, that can be adapted to daily classwork at the high school level anywhere in the world. Therefore, the championship is essentially structured around a collection of well-thought-out e-learning materials (text guidelines, video tutorials, proposed exercises, etc.), providing a more flexible access to content and instruction at any time and from any place. The methodology allows students to gain spatial skills and to practice other transversal abilities, learn the basics of photogrammetric techniques and workflows, gain experience in the 3-D modelling of simple objects and practice a range of techniques related to the science of measurement.

We would like to invite you to join this exciting new project as a chapter contributor. Since this is a textbook, a great deal of this chapter entails a survey on the topic under the paradigm of cyber-physical systems, what can be done onboard and remotely, the distributed nature of the system and some exercises on futurology (anticipating trends can shed some light on upcoming designs). IET will bring great visibility to your work. You are welcome to suggest another topic/chapter title if you feel it would be more suitable. Each chapter should be around 20-25 pages each and can be submitted as a Word or Latex File. The IET will send you additional information (formatting, permission form, etc.) with the contributor's agreement once you have agreed to contribute to the book. Visit http:// www.theiet.org/resources/author-hub/books/index.cfm to get all information you need as a contributor to an IET research-level book. Each book is expected to have a total number of 500 printed pages (based on approximately 550 words per page with a 20% allowance for figures and tables). We have included a tentative schedule and list of topics below. If this is something you would consider, please send me the title of your chapter, a short description/abstract of the chapter content, and your full contact details. We will expect original content and new results for this book. You can, of course, reuse published material but the percentage of material reuse for the chapter should be less than 40%. The IET will run a piracy software on the full manuscript to control that you are including original material and will reject chapters who contain a large amount of already-published material so please do take this into consideration.

The interaction between humanities and scientific disciplines is a slow and recent process, which is still standing influencing more and more frequently the reconstruction of our history. Ancient human remains are a significant part of our heritage, both from a cultural and biological point of view. They keep track of our evolution at a macroscopic and genetic level; for this reason, they must be adequately protected. Since 2018, the Superintendence of Archaeology, Fine Arts and Landscape for the metropolitan city of Bari (Ministry of Culture of Italy) has launched a specific protocol for the management of physical anthropological finds, with the aim of protecting, knowing and enhancing them. The use of new technologies, such as 3D modelling of the finds and the management of all archaeological and anthropological data through DBMS, will allow us to carry out long-term protection. This will be the basis for achieving new studies and enhancement activities on ancient human remains, without increasing their degradation.

This 3D model of the Flagpole was created as a part of Architecture 647: Recording Historical Building course at Texas A&M University (Summer 2014).
The White cement base of the flagpole in front of the Administration Building was a gift from the class of 1934. Three sides are figures depicting the components on which Texas A&M University was founded: military, mechanics and agriculture. Military is represented with a soldier. One woman holding a wheel portrays mechanics. Another woman distributing seeds from a satchel and standing wheat illustrates agriculture. The fourth side lists all the college presidents from 1876 to 1934. The bottom of the base forms a star, allowing the monument to function as a bench.

La Basilica di San Marco a Venezia è da sempre oggetto di rappresentazione come luogo centrale della vita religiosa, culturale e politica della città. Essa diviene oggetto di rilievo puntuale e sistematico nel momento in cui si sviluppa l'idea di recupero delle testimonianze storiche e conseguentemente con la nascita della pratica del restauro dei monumenti antichi, per cui è indispensabile una conoscenza dimensionale e formale dell'edificio, attraverso accurate indagini metriche.
La possibilità di indagare e approfondire a vari livelli la conoscenza della Basilica, attraverso il rilevamento, si è quindi sviluppata nel tempo in rapporto all'atteggiamento culturale nei confronti dell'oggetto architettonico, al progresso scientifico e tecnologico delle strumentazioni e in base alle forme di rappresentazione man mano scelte per la sua descrizione fisica:  soltanto di recente si può affermare di aver raggiunto un bagaglio di conoscenze e una disponibilità di mezzi, che consentono un concreto utilizzo dei rilievi nel lavoro di tutela e di programmazione delle attività di cantiere nel restauro del pavimento musivo della Basilica.
Questo, infatti, per la conformazione fortemente ondulata della superficie e per la complessità geometrica della decorazione, non può essere descritto in modo soddisfacente con i metodi tradizionali di rappresentazione bidimensionale, vale a dire con semplici proiezioni ortogonali in pianta e e sezioni e anche attraverso la restituzione fotogrammetrica di un fotopiano, ma è necessario un modello di descrizione della realtà che tenga conto della terza dimensione.

1. Introduction
The 3D information of an object to be surveyed can be basically acquired in two ways: using stereo image acquisitions or optical distance measurement techniques.
The stereo image acquisition is already known and used for decades in the research community. The advantage of stereo vision to other range measuring devices such as LiDAR, acoustic or radar sensors is that it achieves high resolution and simultaneous acquisition of the surveyed area without energy emission or moving parts. Still, the major disadvantages are the correspondence problem, the processing time and the need of adequate illumination conditions and textured surfaces in the case of automatic matching procedures.
Optical distance measurement techniques are usually classified into three main categories: triangulation, interferometry and Time-of-Flight (ToF).
The triangulation normally determines an unknown point within a triangle by means of a known optical basis and the related side angles pointing to the unknown point. This often used principle is partitioned in a wealth of partly different 3D techniques, such as for instance active triangulation with structured illumination and passive triangulation (Jähne et al., 1999).
Interferometry measures depth also by means of the Time-of-Flight. In this case, however, the phase of the optical wave itself is used. This requires coherent mixing and correlation of the wave-front reflected from the object with a reference wave-front. Also in this case, many variants of the optical interferometry principle have been developed, such as multi-wavelength interferometry, holographic interferometry, speckle interferometry and white light interferometry (Jähne et al., 1999). The high accuracies of distance measurements performed with interferometry mainly depend on the coherence length of the light source: interferometry is not suitable for ranges greater than few centimeters since the method is based on the evaluation of very short optical wavelength.
Continuous wave and pulse ToF techniques measure the time of flight of the envelope of a modulated optical signal. These techniques usually apply incoherent optical signals. Typical examples of ToF are the optical rangefinder of total stations or classical LiDAR instruments. In this latter case, actual laser scanners allow to acquire hundreds of thousands of points per second, thanks to fast scanning mechanisms. Their measurement range can vary to a great extent for different instruments; in general it can vary between a tens of meters up to some kilometers, with an accuracy ranging from less than one millimeter to some tens of centimeters respectively. Nevertheless, the main drawbacks of LiDAR instruments are their high costs and dimensions.
In the last few years a new generation of active sensors has been developed, which allows to acquire 3D point clouds without any scanning mechanism and from just one point of view at video frame rates. The working principle is the measurement of the ToF of an emitted signal by the device towards the object to be observed, with the advantage of simultaneously measuring the distance information for each pixel of the camera sensor. Many terms have been used in the literature to indicate these devices, which can be called: Time-of-Flight (ToF) cameras, Range IMaging (RIM) cameras, 3D range imagers, range cameras or a combination of the mentioned terms. In the following the term ToF cameras will be prevalently employed, which is more related to the working principle of this recent technology.
Such a technology is possible because of the miniaturization of the semiconductor technology and the evolvement of the CCD/CMOS processes that can be implemented independently for each pixel. The result is the possibility to acquire distance measurements for each pixel at high speed and with accuracies up to about one centimeter. While ToF cameras based on the phase-shift measurement usually have a working range limited to ten/thirty meters, RIM cameras based on the direct ToF measurement can measure distances up to 1500 m. Moreover, ToF cameras are usually characterized by low resolution (no more than a few thousands of tens of pixels), small dimensions, costs that are an order of magnitude lower with respect to LiDAR instruments and a lower power consumption with respect to classical laser scanners. In contrast to stereo, the depth accuracy is practically independent of textural appearance, but limited to about one centimeter in the best case (actual phase-shift commercial ToF cameras).
The field of real-time ToF camera-based techniques is very active and covers many areas only briefly mentioned in this thesis, which is rather focused on ToF cameras in the Geomatics field.

1.1 Motivation
At present the ability to capture the surrounding area at high speed in three dimensions is one of the most challenging tasks in many fields, such as industrial automation and production, mobile mapping, monitoring, automotive safety, autonomous mobile robotics and gaming.
For both dynamic and static scene there is no low-price off-the-self system that provides full range, high-resolution distance information in real time such as in the case of ToF cameras.
Nevertheless, RIM cameras are usually characterized by some systematic measurement errors, which can strongly worsen the achievable distance measurement accuracy up to tens of centimeters in some cases. Therefore, suitable calibration procedures have to be developed.
One of the main topic of this thesis is to propose systematic procedures for the distance calibration of commercial ToF cameras, in order to estimate and increase their measurement accuracy. The calibration procedure presented in this work belongs to the direct calibration methods, since the distance measurement accuracy of RIM cameras is directly estimated and the resulting systematic errors are modeled. The main idea is to propose a procedure which does not require additional digital cameras or cost-effective high precision measurement racks or robot-arms to calibrate ToF cameras and which can be applied to any kind of RIM camera.
Suitable experimental tests are proposed in order to analyze the influence of several factors on the distance measurements, such as the camera warm-up during working time, the angle of incidence between the camera axis and the object surface, the presence of foreground objects close to the camera and the object reflectivity.
The second main topic of this work is the use of ToF cameras in the Geomatics field, with the final aim of 3D object reconstruction. Since ToF cameras acquire 3D point clouds at video frame rates, this potentiality can surely be exploited for this purpose. The main problem to be faced is the registration of the point clouds acquired from different view-points with ToF cameras. For this purpose, an algorithm for ToF point cloud registration has been developed, which is called multi-frame registration algorithm. Exploiting both the amplitude images and the 3D information delivered by ToF cameras, the proposed algorithm allows to automatically perform the point cloud registration with a final accuracy which is very close to the measurement accuracy of the employed device. Such a result is obtained thanks to frame averaging (so why the term “multi-frame”) and custom-built procedures, also applying an effective filter proposed in this work, which practically removes all “mixed pixels” from the acquired data. Mixed pixels are outliers resulting from the way ToF cameras process multiple returns of the emitted signal: they can strongly affect the accuracy of the acquired point cloud especially in the case of complex scenes. Another challenging topic proposed in this thesis is the integration between ToF data and a multi-image matching approach for automatic 3D object breakline extraction, which can be very useful for speed-up the drawing production of the surveyed objects. In both cases, some improvements are proposed and discussed for future developments.

1.2 Outline
This thesis is organized in six chapters. After this brief introduction, the following chapter faces with the working principle of ToF cameras, dividing them in two categories: devices based on the direct ToF principle and devices which use the indirect ToF principle (phase-shift measurement). Then, the state of the art of this technology is reported, with a complete overview about commercial ToF cameras. A description of the measurement parameters and the typical distance measurement errors of ToF cameras based on the phase-shift measurement (which are the most diffused) is reported, in order to show pros and cons of this new technology.
In Chapter 3, one of the main topics of this thesis is presented, which is the distance measurement calibration of ToF cameras. First, a minimum time (warm-up time) of camera working is established for both the SR-4000 and the PMDCamCube3.0 cameras in order to achieve distance measurement stability. Then, the relation between integration time and distance measurement precision in analyzed for both devices. A distance measurement accuracy evaluation system for the SR-4000 camera is reported, which can be applied for any ToF camera model, and a distance calibration model is proposed which increases the distance measurement accuracy in a wide interval of the whole working range of the camera. Then, a procedure to evaluate the influence on distance measurements of the orientation of the acquired object surface with respect to the camera axis is proposed. The problem of “internal scattering”, which can arise when foreground objects close to the camera are present, is also faced for the SR-4000 camera; finally, some tests on object reflectivity are reported in order to test the performance of ToF cameras on real objects surfaces.
In Chapter 4 a brief summary on the state of the art of applications using ToF cameras is reported, with the aim of showing how this new technology is spread...

As small unmanned aircraft Systems UASs are emerging from the horizon, it is uplifting to see
technology saving lives because the AEC industry is one of the world’s deadliest jobs, according to
Forbes (Smith, 2014). Consequently, by reducing exposure and preemptively targeting the inspection
pipeline process, aerial surveying is a new market with the potential to pioneer solutions for surveying
construction sites and relaying as-built information to headquarters. The ability to immediately see,
hear, and communicate allows companies to optimize a strategy for economically and safely
prioritizing tasks to laborers, from automated safety checks, RFID tagging, thermal/volumetric scans,
to photogrammetry.

Therefore, this paper presents a guideline to prepare façade specialists in commercial UAV
operation and technically evaluate and explore the main challenges in addressing ‘autonomous flight
and integration of collected data into the existing BIM software’ inspired by (Dupont, 2017). As there
is no definite protocol for façade surveying, the goal is to define the limitations of DJI’s latest drone,
Matrice 210, equipped with upgraded IMU/GPS & camera sensors, and to confirm accuracies for
1mm,2mm,4mm, and 10 mm ground sampling distance (GSD). Through photogrammetry, the survey
will compare ground control points (GCPs) with a TS/TSL surveyor and transform photographs into an
ortho-mosaic 3D model, and lastly contribute a program to discuss BIM interoperability. As managing
the façade sector requires processing large quantities of data and different installation constraints,
the paper’s second object is to create a tool using BIM/KBE/MDO to link the model to Rhino-
Grasshopper-Flux-Dynamo-Revit workflow and assess the façade & fabrication challenges suggested
by (Voss, 2013).
With this extensive guideline, the study concludes (1) that photogrammetry is acceptable using
2mm & 4mm GSD, (2) while Lidar requires further integration for aerial surveying. This scenario to
capture the real world for AEC values will increase transparency between as-built and as-drawn by the
designer/contractors and enhance the protocol for façade surveys.

Since 2005 the Aswan-Kom Ombo Archaeological Project (AKAP), managed by Yale and Bologna Universities, has investigated a number of selected areas in the region between Aswan and Kom Ombo. Many of the rock art sites identified within the concession areas are under threat, due to the impact of modern human activities. Three-dimensional technologies, such as digital surveying, laser scanner and photogrammetry, were used for the first time in the Egyptian Nile Valley in order to document the rock art and its environmental setting in a very detailed manner. The aim is that of improving data recording and analysis while saving economic resources and reducing field work time.

FORTHCOMING: Our paper focuses on modern techniques of documentation, such as photogrammetry and laser scanning and later analysis in a virtual environment of the Ancestral Pueblo sites, with sandstone architecture and rock art that are located in several canyons of the central Mesa Verde region, southwestern Colorado, USA. All of the sites roughly date back to the 13th century A.D. and could have functioned as a community of allied sites. The research was conducted over the course of several seasons by the Sand Canyon-Castle Rock Community Archaeological Project led by the Institute of Archaeology at the Jagiellonian University in Kraków. The goal of digitising the Ancestral Puebloan sites was to accurately document and analyse the condition of preservation of the architectural features and rock art. The registered data have been used to generate accurate 2D documentation together with 3D models. The 3D models that were generated have also been used to interpret some barely visible details, for example of the petroglyphs, by varying the position of the light, with the use of Reflectance Transformation Imaging (RTI) software. Another element is the virtual three-dimensional models that we used in a game engine and Digital Elevation Model that encompasses the sites and the associated environment. Also, we briefly discuss the potential and the benefits and disadvantages of using specific methods in the field in the research area, mainly photogrammetry, laser scanning, and RTI analysis.

Advancement in aviation technology has greatly improved the processes of acquiring images for map production. Over the years images acquired by aircraft and satellite technologies have been the only sources of images for map production. This technically made map production by photogrammetric method an esoteric endeavour available to advanced technologies. The huddles in the way of its use in developing countries included cost, time, expertise and others. In recent times, the combination of advancements in computer and aviation technologies has produced robotic aircrafts called drones which though unmanned, can be used to acquire images from the air and almost in any location even impossible for regular aircraft imaging system. This innovation is also cheap to acquire and cheap to deploy and to maintain. So, research focus has turned to investigating the use of drone captured images in mapping large geographic areas. Therefore, this project deals with investigation into the geometric accuracy of a drone acquired block of images using analytical two platform orientation and spatial intersection. The aim of this project is to investigate the geometric accuracy of a drone acquired block of images. The drone technology used is an Unmanned Fixed-Wing Aircraft System. To fulfil the aim of this project, block of images of Faculty of Education, University of Lagos acquired from an Unmanned Fixed-Wing Aircraft System was obtained. A stereo pair was extracted from the block of images with 60% overlap. Measurement of image coordinates of control, check and detail points was achieved using AutoCAD software as a mono-comparator simulator. The ground survey for control and check points establishment was achieved using Promark 3 Differential Global Positioning System (DGPS). MATLAB program was developed to compute the exterior orientation parameters of the stereo image and subsequently the 3D object space coordinates of control, check and detail points were computed. Statistical analysis was done to evaluate the geometric accuracy of the stereo image using coordinates obtained from ground and photogrammetric survey methods. The root mean square error (RMSE) in plan was 20-50cm for positional accuracy while that for height was 40cm. The relative error obtained for distance measurement is approximately 1:100 while that for area measurements are approximately 0.3:100 and 7:100. Based on the findings of this study, it is concluded that 1 drone (UAV) techniques can replace other methods of surveying as the main method of data capture for engineering projects, boundary mapping and topographical surveying.

Graffiti and street art are unique forms of cultural heritage which have not yet received the scientific attention they deserve. The potential of graffiti research to answer a variety of social and cultural research questions is underexploited. One reason for this lack of academic rigor lies within the very sparse availability of well-curated and publicly accessible graffiti data. One obvious foundation for a graffiti dataset is images depicting the various pieces, tags or throw-ups. The few existing graffiti image databases do not allow the study of the graffiti’s exact shapes and dimensions as the photographs suffer from various distortions which are introduced by topography, perspective, or the camera itself. Orthophotos have the great advantage of removing above-mentioned image distortions. The creation of orthophotos, however, is time-consuming and requires considerable manual interaction, which poses a significant obstacle considering that comprehensive and up-to-date graffiti databases often deal with hundreds of images per week.

Here, we present a novel methodology which overcomes the above-mentioned limitations in present-day graffiti documentation by deriving graffiti orthophotos in a highly automated way. In contrast to conventional photographs, orthophotos are adjusted for the graffiti surface topography and had all perspective and lens distortions removed. As a result, orthophotos allow the measurement of coordinates, distances, and areas of the depicted graffiti, enabling the derivation of exact proportions and relating the object to a real-world geographic coordinate reference system. Orthophotos in this context are therefore accurate maps of graffiti. The derivation of orthophotos, however, is complex and requires not only exact knowledge about the three-dimensional surface geometry of the object but also about the camera’s internal geometry and its exact location and orientation in space. We are developing a photogrammetric methodology and associated tool that derives the required information based on graffiti photos and outputs the desired orthophotos without any manual intervention during the process.

In this talk, we present this bespoke photogrammetric approach which is currently investigated in the framework of the graffiti documentation and dissemination project INDIGO and is built as a Python add-on to the commercial package Agisoft Metashape Professional. First tests were conducted at the Donaukanal (Eng. Danube Canal), a central waterway through Vienna and a famous graffiti hotspot. The results indicate a reliable performance of our approach: the majority (ca. 85%) of the tested graffiti images were successfully and automatically turned into orthophotos. We will present those results and discuss where further finetuning is needed and demonstrate why the presented tool has the potential to largely automize the way graffiti are being documented. This approach will enable the building of a solid and extensive database for advanced graffiti research.

An attempt to summarise the many years old research of Kraków archaeologists in cooperation with many institutions was the starting point for this popular science book.  The monuments of the cultural heritage of Paphos, like Kraków, have been present in the UNESCO list for years. The cultural heritage can be shown in many ways. On the following pages of this publication, we introduce it to the readers in the light of the so-called new technologies. Cultural heritage was the hero not only of this book, but also for the whole year 2018which has been announced as the European Year of Cultural Heritage (EYCH). WE ar proud of the fact that this publication has been covered by the patronage of the EYCH 2018. We present the cities of Kraków and Paphos, pearls of thr UNESCO list, as well as the relations between Kraków and Cyprus, which are not limited to today's mass tourism but go back many centuries. The main part of th epublications contains 18 texts written by 35 authors; they are divers and show richness of the ne technologies used.

Although alternatives have become available, pen and ink drawings of stone tools dominate archaeological publications. Despite the existence of a conventional illustration framework, the work produced by illustrators can be inconsistent and hinges on skill level
and time commitment. Discussions going back to the 1880s critically question the use of illustrations for the purpose of scientific publication. Alternatives, such as laser scanning and photogrammetric modeling, are now available for displaying lithics. These alternatives can remove the subjectivity involved in artistic rendering, creating replicable results, regardless of who is collecting the data. In addition to creating more regularized and objective representations, there are a significant number of analytical and other benefits to adopting novel imaging techniques to depict stone tools in publications. A set of three-dimensional (3D) models are presented here to demonstrate the capabilities of laser scanning and, potentially, photogrammetric modeling as replacements for lithic illustration.

This diploma thesis introduces the production of cylindrical and spherical panoramas and explains how to link individual panoramas to make a virtual tour. The designing process of the virtual tour of the Dresden University of Technology campus is explained in this work. The author spent his fifth year of his studies (1.10.2004 - 30.06.2005) at the Dresden University of Technology in Germany. The virtual tour of the Dresden University of Technology campus can be found in the
Internet: www.kwiatek.krakow.pl/panotour. In order to view all interactive panoramas one will need to install proper plug-ins that are mentioned on the webpage.

The creation of 3D models of artifacts is
becoming an increasingly common practice
within archaeology. Structure from motion (aka
photogrammetry) is a method of producing
models using only digital photographs.
Photogrammetry has several advantages over
other techniques, such as laser or structured
light scanning. These include cost, portability,
and adaptability for use in field conditions. This
poster, presented at the 2015 SAA annual meeting, describes a photography rig that was
developed to systematically capture images in
a manner that is designed to consistently result
in high-quality photogrammetric models.

J. Reinhard, 3D-Dokumentation mit Drohne. In: M. Sauter (Hrsg.), Surenenpass. Archäologie und Geschichte in Attinghausen. Archäologische Prospektion - Archaeological Survey 1 (Hochwald 2016), 172-183.

For the 3D models see https://sketchfab.com/archaeobotics/collections/attinghausen-geissruggen-ur-schweiz.

Photogrammetry is a discipline which allows objects to be scanned in a fairly automated way and at a
reasonable cost compared to other scanning methods. For some years this technique has been employed
in the field of cultural heritage, especially for purposes of documentation, but also as a tool to produce
orthophotographs, replicas or to obtain base models to make virtual restorations and recreations, among other
uses. The direct applications possible are of great interest to professionals in preservation-restoration and this
paper presents case studies which may help to propagate its standardisation in various work processes.

Ladies, gentlemen and distinguished guests,
My name is Murat YAKAR and I am the chair of Intercontinental Geoinformation Days. It is my honour
this morning to welcome you all.
It is a great pleasure for me to declare open the first Intercontinental Geoinformation Days and to
welcome the participants from all over the world who participated here to exchange experience and
work together for two days on field of geoinformation and their applications.
I first wish to extend to you the greetings of the Governor of Mersin Province, Metropolitan Mayor of
Mersin and the rector of Mersin University. I wish to thank them for their support.
This 2-days-long conference offers online technical sessions and workshops. The technical programme
consists of 67 presentations within the fields of surveying, remote sensing, photogrammetry, land
administration, cartography, GIS and geodesy, including best practice and new research.
As the novel coronavirus outbreak shutters businesses and disrupts everyday life for billions around
the globe, massive annual conferences and small society meetings alike have moved online. This new
format poses numerous technical and organizational challenges, but it also offers opportunities—for
reaching wider audiences, reducing the carbon footprint of meeting travel, and improving diversity
and equity.
As a way to support our research community and to advance its scholarship during the COVID-19
pandemic, we decided to waive all registration fees for the virtual conference, cover the administrative
and setup cost of hosting the conference virtually as well as the publishing and copy-editing costs of
the conference proceedings.
The Intercontinental Geoinformation Days has gotten an enthusiastic response from colleagues from
all around the World. And we are pleased with the positive response that this event has gotten dozens
of contributions from experts in the field. The number of submitted papers is more than the level we
had expected. So, I would like to thank you for your valuable contributions and kind support.
Our team is now considering to make this event traditionalized and the second IGD event is planned
to be organized in May 2021. The organization committee will publish the details of the next event in
the following months.
Before closing, I have to extend further thanks to academic staff of Mersin University Department of
Geomatics Engineering who greatly helped in organising the conference. I sincerely hope that this
conference will achieve its objectives and make great progress through wide ranging discussions.
Let me now close by wishing you a delightful and stimulating event.
Prof. Dr. Murat YAKAR

Several digital technologies are now available to record and document archaeological excavations. A large number of studies have been published concerning the use of laser scanning, image based 3D modelling and GIS. By integrating different typologies of 3D data from Uppåkra, an Iron Age central place in southern Sweden, this thesis focuses on the development and evaluation of how 3D Geographic Information Systems (3D GIS) affect archaeological practice. In specific a Digital Terrain Model (DTM) was created for the site and the surrounding landscape. A UAV (drone) was used to document the excavation area in higher resolution, and image based 3D modelling was used to record the ongoing excavation on a single-context level. These different typologies of data were subsequently imported in a 3D GIS system (ArcScene) in order to conduct various types of spatial analysis (e.g. hillshade and slope analysis) as well as to create 3D drawings of the excavated contexts, using the textured 3D models as a geometrical reference. The ability to virtually revisit previous stages of the excavation and the use of tablet PC’s for documentation and discussion at the trowel’s edge increased reflexivity on the excavation and stimulated on-site interpretation by the excavation team. The model based drawing approach furthermore improved the drawing resolution compared to traditional documentation using a total station, especially for complicated contexts. This approach allowed connecting different typologies of data in the same virtual space, 1) increasing the possibility of researchers and scholars to gain a complete overview of all the information available, as well as 2) exponentially increasing the possibilities to perform new analysis. The ability to interact and navigate with all the data in 3D improved the impact of the data and comes closer to simulating the real world. Though some challenges still have to be faced, such as inaccurate georeferencing and unrealistic colour projection, the method was found to significantly improve the documentation quality by creating a multi-scale 3D documentation platform. By further developing this method, it can help us to improve the standards of archaeological excavation documentation.

In 2010, a new off-the-shelf software for Computer Vision Photogrammetry, Agisoft PhotoScan, became available to nautical archeologists, and this technology has since become a popular method for recording underwater shipwreck sites. Today (2015), there are still active discussions regarding the accuracy and usage of Computer Vision Photogrammetry in the discipline of nautical archaeology. The author believes that creating a 1:1 scale constrained photogrammetric model of a submerged shipwreck site is not difficult as long as archaeologists first establish a local coordinate system of the site.  After creation of a 1:1 scale constrained photogrammetric model, any measurements of the site can be obtained from the created 3D model and its digital data. This means that archaeologists never need to revisit the archaeological site to take additional measurements. Thus, Computer Vision Photogrammetry can substantially reduce archaeologists’ working time in water, and maximize quantity and quality of the data acquired.
Furthermore, the author believes that the acquired photogrammetric data can be utilized in traditional ship reconstruction and other general studies of shipwrecks. With this idea, the author composed a new methodology that fuses Computer Vision Photogrammetry and other digital tools into traditional research methods of nautical archaeology. Using this method, archaeologists can create 3D models that accurately represent submerged cultural heritage sites, and these can be used as representative archaeological data. These types of representative data include (but are not limited to) site plans, technical artifact or timber drawings, shipwreck section profiles, georeferenced archaeological information databases, site-monitoring systems, digital hull fragment models and many other types of usable and practical 3D models. In this dissertation, the author explains his methodology and related new ideas.

Photogrammetry has become increasingly popular as a low-cost method for documenting cultural heritage and archaeological excavations. However, we have yet to establish best practices for its implementation at the site, or methods for assessing the accuracy of the resulting 3D measurements. This article presents a recent study of the Temple of Hera at Olympia, where a 25 x 55 m area was recorded at 1 mm resolution using photogrammetry both for survey and 3D reconstruction. Coded targets were set up throughout the site, which was then photographed in two phases. First, a site-wide survey established the locations of the network of targets. Second, sets of close-up photographs for detailed 3D reconstruction of the site were registered to the global survey via the targets. This technique developed at Olympia improves measurement accuracy by an order of magnitude compared to previous implementations, with a precision of at least 1 part in 50,000, and 95% of the surfaces located accurately within 2-3 mm.

Methods of estimating the total amount of above-ground biomass (AGB) in crop fields are generally based on labourious, random, and destructive in situ sampling. This study proposes a methodology for estimating herbaceous crop biomass using conventional optical cameras and structure from motion (SfM) photogrammetry. The proposed method is based on the determination of volumes according to the difference between a digital terrain model (DTM) and digital surface model (DSM) of vegetative cover. A density factor was calibrated based on a subset of destructive random samples to relate the volume and biomass and efficiently quantify the total AGB. In all cases, RMSE Z values less than 0.23 m were obtained for the DTM-DSM coupling. Biomass field data confirmed the goodness of fit of the yield-biomass estimation (R2 = 0,88 and 1,12 kg/ha) mainly in plots with uniform vegetation coverage. Furthermore, the method was demonstrated to be scalable to multiple platform types and sensors.

The current work investigates the potential of two low-cost off-the-shelf quadcopters for multi-view reconstruction of sub-vertical rock faces. The two platforms used are a DJI Phantom 1 equipped with a Gopro Hero 3+ Black and a DJI Phantom 3 Professional with integrated camera. The study area is a small sub-vertical rock face. Several flights were performed with both cameras set in time-lapse mode. Hence, images were taken automatically but the flights were performed manually as the investigated rock face is very irregular which required manual adjustment of the yaw and roll for optimal coverage. The digital images were processed with commercial SfM software packages. Several processing settings were investigated in order to find out the one providing the most accurate 3D reconstruction of the rock face. To this aim, all 3D models produced with both platforms are compared to a point cloud obtained with a terrestrial laser scanner. Firstly, the difference between the use of coded ground control targets and the use of natural features was studied. Coded targets generally provide the best accuracy, but they need to be placed on the surface, which is not always possible, as sub-vertical rock faces are not easily accessible. Nevertheless, natural features can provide a good alternative if wisely chosen as shown in this work. Secondly, the influence of using fixed interior orientation parameters or self-calibration was investigated. The results show that, in the case of the used sensors and camera networks, self-calibration provides better results. To support such empirical finding, a numerical investigation using a Monte Carlo simulation was performed.

Scope of the book:
This book focusses on the technical concepts of deep learning and its associated branch Neural Networks for the various dimensions of image processing applications. The proposed volume intends to bring together researchers to report the latest results or progress in the development of the above-mentioned areas. Since there is a deficit of books on this specific subject matter, the editors aim to provide a common platform for researchers working in this area to exhibit their novel findings.
Topics of Interest:
This book solicits contributions, which include the fundamentals in the field of Deep Artificial Neural Networks and Image Processing supported by case studies and practical examples. Each chapter is expected to be self-contained and to cover an in-depth analysis of real life applications of neural networks to image analysis.