Technical advances in the field of remote sensing have made it possible to create a large number of datasets with very high spectral, temporal or spatial resolution, however, in the field of...Show moreTechnical advances in the field of remote sensing have made it possible to create a large number of datasets with very high spectral, temporal or spatial resolution, however, in the field of archaeology, the evaluation of this data is still largely a manual undertaking. The issue with manual interpretation is that human interpreters are increasingly having difficulty coping with the sheer amount of data while in some cases, the human eye is not capable of processing the full range of information contained in these datasets. It is for this reason that (semi-)automatic classification workflows need to be developed in order to aid human interpreters in their image classification tasks. This thesis is concerned with the development of a Geographic Object-Based Image Analysis (GeOBIA) workflow for classifying LiDAR visualisations containing heterogeneous and linear objects. The study area that this workflow is applied to is the terraced landscape of the Lower Engadine, Switzerland, where the complex and steep terrain contains multiple agricultural terraces, irrigation/drainage ditches, roads and more. The workflow makes use of only FOSS (Free and Open Source Software) applications in order to ensure full transparency, accessibility and reproducibility of the classification results. For this purpose, a number of FOSS and proprietary software was tested in order to determine the user friendliness, suitability and effectiveness of each of the options. In order to develop the final workflow, a number of studies regarding the suitability of different LiDAR visualisations as well as training data input options and smoothing filters were carried out. The final workflow makes use of an unfiltered slope visualisation, consists of six steps with an optional seventh step, and is capable of producing classification results that hold up against manual mapping results of the terrace edges that were used as a benchmark. Finally, in order to assess whether the classification results generated by the workflow are useful to a human interpreter, a user study was carried out. 13 out of the 14 users stated that the classification results were helpful to them and because the workflow takes no longer than 5-10 minutes to carry out, it can be said that this workflow is capable of producing a useful classification of the study area with minimal time and effort.Show less
The use of 3D models has steadily increased within archaeology, leading to the adoption of many 3D digital data acquisition techniques and 3D quality assessments. Yet the problem remains of how 3D...Show moreThe use of 3D models has steadily increased within archaeology, leading to the adoption of many 3D digital data acquisition techniques and 3D quality assessments. Yet the problem remains of how 3D models and 3D file formats can be opened 10 or 20+ years after they have been generated. 3D Data preservation for the long-term is a predicament that current archaeological digital archives are dealing with. Correct preservation has to consider the purpose of current 3D models and what 3D models can offer for future research aspects. Legal, institutional and technical aspects influence preservation as well and combined with the digital archive and user perspectives, form the stakeholders of 3D data preservation. The used 3D data of this thesis are photogrammetric-generated 3D models of Uruk pottery of Jebel Aruda. The focus of this thesis is to demonstrate how existing object-based archaeological 3D data should be converted and presented within a dataset to consider the requirements of all the stakeholders. This thesis presents a workflow for generating a dataset of object-based archaeological 3D models for EASY. EASY is a certified digital archiving system in the Netherlands that assumes responsibility for long-term preservation of research data and accessibility of digital objects. The workflow only addresses stakeholder requirements that are essential for digitally preserving 3D data for the long-term. This workflow is assessed on its adherence to the FAIR principles, on the fit for purpose of 3D file formats for object-based archaeological 3D models and lastly, the required tools and applicability of Free and Open-Source Software (FOSS). The workflow consists of four steps with the first step addressing ethical considerations and the second step directory structuring and file naming. The third step involves importing the original 3D file in Blender and exporting the file to six preservation recommended 3D file formats. The last step of the workflow is to generate three levels of documentation using metadata and paradata. Three evident results emerged from this thesis. The research indicates that of the six recommended 3D file formats, the combination of the FBX and OBJ file formats provide the most value for preserving object-based archaeological 3D models. The research also suggests that the generated 3D dataset not completely adheres to the FAIR principles, but that elements which are not fully addressed do not inherently alter the outcome of the interoperability or reusability. Lastly, the thesis has shown that it is possible to generate a preservation-ready 3D dataset using only FOSS. Although archaeological and preservation specifications can be researched further, object-based archaeological 3D datasets can be generated in a cost-free and transparent production.Show less
