Jonas Luft

In recent years, libraries have made great progress in digitising troves of historical maps with high-resolution scanners. Providing user-friendly information access for cultural heritage through spatial search and webGIS requires georeferencing of the hundreds of thousands of digitised maps. Georeferencing is usually done manually by finding “ground control points”, locations in the digital map image, whose identity is unambiguous and can easily be found in modern-day reference geodata/mapping data. To decide whether two symbols from different maps describe the same object, their semantic and spatial relations need to be matched. Automating this process is the only feasible way to georeference the immense quantities of maps in conceivable time. However, automated solutions for spatial matching quickly fail when faced with incomplete data – which is the greatest challenge when comparing maps of different ages or scales. These problems can be overcome by computing map similarity in t...

In a complex urban scenario with a growing number of stakeholders and high dynamic developments, decision makers rely heavily on public data to make informed decisions. Often though, the available data is heterogeneous and stems from incomplete or inconsistent sources. The planning process, especially the definition of planning goals/needs, is often delayed due to time-consuming data procurement and assessment. This paper describes the development of the Cockpit Social Infrastructure (CoSI), a GIS-based planning support system that serves as an easy-access interface between Hamburgs Urban Data Platform GIS data infrastructure and the municipal planners for social infrastructure, bridging the gap between disciplines and facilitating communication and decision-making between stakeholders. CoSI takes full advantage of the UDP infrastructure and aims to introduce a city-wide tool for planners to conduct holistic, evidence-based planning, grounded in the latest and regularly updated stat...

Libraries and researchers face a big challenge: sometimes thousands, millions of maps are being conserved in archives to retard deterioration, but this makes it hard to obtain specific knowledge of their content, sometimes even of their existence. In recent years, the efforts have increased to digitise historical documents and maps to preserve them digitally, make them accessible and allow researchers and the general public a less restricted access to their heritage. But maps are more than a cultural artifact: they are data. Data about the past that can very well be important for science and decision-making today.
The problem is, the vast amount alone makes it hard to know what to look for. Maps are usually archived and catalogued with limited meta-information, sometimes obscuring their actual content. This makes it impossible to find specific information without expert knowl-edge on history and cartography. Extracting the content, i.e. data, of scanned historical maps is a necessity to make the content searchable and to use modern digital tools for automatic processing and analyses.
To combine data from different maps and compare them with modern geospatial data, georeferencing is paramount. This is usually done by hand and needs a lot of time and spe-cialised training. We explore if and how usable GCP can be found automatically in historical maps with computer vision and document analysis methods of today. In this work-in-progress report, we use OCR on map labels and geocoding of persisting geographical feature designation for successful first experiments. This shows text recognition and vectorisation to be a promising research direc-tion for large-scale automated georeferencing of historical maps.