Wikidata:WP EMEW/Map uploads/Horizon

Page for longer-term ideas, and general thoughts about georeferencing

Info from CarterGraph onto (unwarped) old map

Export of manifest from CarterGraph

use the CarterGraph UI to select a subset of the data - eg particular layers, particular part of the country

export as annotations on a blank globe, for consumption by map-IIIF toolchain

Warping reality onto an old map

eg to decorate a Saxton map in its original coordinates with information from the GIS

import the annotated blank globe

inverse-warp it to the implicit Saxton projection

decorate the unwarped map

this is exactly a use-case for the map-IIIF tool that Bert is working on

Map warping beyond splines

Map-warping including projection estimation

probably not an issue for EMEW, which doesn't need maps beyond England and Wales

but for an old map, eg of the whole of Europe, it's a lot to ask the spline interpolation to cope with fitting eg conical -> web mercator as well

is it reasonable to function-fit by trying to estimate the gross proj -> proj transformation first, then use classic georeferencer fitting on the residuals ?

Map-warping interpolation using non-spline basis functions

eg to deal with difficulties MoL had with Layers-of-London John Rocque map -- splines could not cope well with locally flat areas with dodgy joins

could other basis functions do better (some form of radial basis functions?)

or some other way to model the warping ?