DIGITAL LIBRARY
ANALYSIS AND OPTIMIZATION OF KML FILES
University of Debrecen, Faculty of Informatics (HUNGARY)
About this paper:
Appears in: INTED2020 Proceedings
Publication year: 2020
Pages: 4209-4216
ISBN: 978-84-09-17939-8
ISSN: 2340-1079
doi: 10.21125/inted.2020.1175
Conference name: 14th International Technology, Education and Development Conference
Dates: 2-4 March, 2020
Location: Valencia, Spain
Abstract:
In Hungary, universities are expected to offer geoinformatics courses for their students majored in Computer Science degree programmes. The University of Debrecen, Faculty of Informatics also give the possibility for its students to take some courses related to geographic information systems at both bachelor and master levels. During these classes, students can get in touch with the basic concepts of geoinformatics as well as they learn how to create, import, analyse, process and export geospatial data in different formats.

QGIS is a free and open source geographic information system that can read and write different data formats. It supports both raster and vector contents which are organized into layers. Users can compose, transform and export their data with the use of QGIS software, while additional free plugins developed in high level programming languages (e.g. Python) enrich its core functionality. As our students also have courses dealing with markup languages, we also intruduce XML-based (Extensible Markup Language) geospatial formats. The OSM format of the Open Street Map might be a good choice if someone would like to deal with open data, but Keyhole Markup Language (KML) is also a popular alternative if the main objective is the geovisualization of your data for example with Google Earth. Although students can compose and save their custom geospatial data easily with the desktop application or its brand-new in-browser alternative, not all of the KML features are available via the user interfaces. Furthermore, KML files generated by the desktop application store redundant styling information which not only increases the file size but makes it harder to modify the content.

In 2019, we started a brand-new development which is supported by The New National Excellence Program of the Ministry of Human Capacities of Hungary. Our goal is to design and develop an online environment, which can deal with the above mentioned issues. At the beginning of 2020, we are going to launch a web service which can consume KML documents and validate them. On the other hand, the application will also offer a feature that compresses the KML documents by detecting and modifying the unnecessarily redundant parts of them. With this application our students can validate their code and get suggestions about how they can minimize the size of their KML files. Thus, they can improve their coding skills and learn how to design better-structured documents.
Keywords:
Geoinformatics, geospatial data, KML, optimization.