Allmaps

International Image Interoperability Framework is a set of open standards for serving high-resolution images of paintings, old manuscripts but also maps. Allmaps is a free and open source set of tools to work specifically with IIIF Images of maps: georeferencing them using Georeference Annotations, linking pixel coordinates on the image with geographic coordinates on the globe. This enables adding such maps as an overlay to webmaps, projecting and warping them as needed, via plugins for all popular open source mapping libraries (MapLibre, OpenLayers and Leaflet).

Over the past years, an open database has been collected as part of this project containing tens of thousands of georeferenced maps. In order to make this database explorable, we need to take some next hurdles: this project will develop a handful of computational geometry algorithms that allow efficient clustering of map masks, efficient vector tile rendering of masks, intuitive user interaction to select masks and Exposé-like automatic re-ordering of masks. Together with improvements in the rendering pipeline and the Georeference Annotation spec, these will be the open source building blocks for a user-facing Allmaps Explore application, while also being reusable in other (map-related) projects. This will make it easier and more inspiring to curate, georeference and explore collections of digitised maps.