User:Multichill/Map warping format

Map warping is the concept of taking one map and putting that on the other map where the first map is just an image. You can see it on https://warper.wmflabs.org/ . In the current situation the warping data is not stored on Commons. This data should be stored on Commons so that anyone can grab the file and the warping data and plot it.

On https://github.com/bertspaan/wikimania-hackathon-2019 a prototype was build that stores the data on Commons, but it has a big drawback: It stores the data in three different files:

• GCPs: Data:Pigot_and_Co_(1842)_p2.138_-_Map_of_Lancashire.gcps.tab. This stores a list of geo control points. Each control point is the x and y in the bitmap and the latitude and longitude on the map.
• Pixel mask: Data:Pigot_and_Co_(1842)_p2.138_-_Map_of_Lancashire.mask.tab. This stores a list of pixels to cut the image.
• Map mask: Data:Pigot_and_Co_(1842)_p2.138_-_Map_of_Lancashire.mask.map. This stores a list of coordinates

All this data is required to store the warping data of the image File:Pigot and Co (1842) p2.138 - Map of Lancashire.jpg. I would like to store this data in one file which is geojson compatible.

Mapwarper also has the concept of mosaics: Multiple warped maps that form one big map. We should support that too at some point.

Geojson warped file

Testing at Data:Georectification.example.geojson.map. The file should contain in basic info:

• License
• Description
• Source(s)
• Latitude and longitude
• Zoom

In the geojson part (data):

• geo control points (gcp): List of lat/lon + x/y
• geo mask: List of lat/lon
• pixel mask: List of x/y

(can geo and pixel mask be combined? Does every geocordinate in the mask list correspond to a pixel in the pixel mask list?)

• Name of the file it applies to
• Entity id of the file it applies to
• Hash (sha1) of the file it applies to

Links

• https://github.com/bertspaan/wikimania-hackathon-2019 prototype
• https://tools.ietf.org/html/rfc7946 geojson rfc
• Data:Georectification.example.geojson.map example
• http://geojson.io to test geojson
• d:Wikidata:Property proposal/georeferencing data proposal for new property to link the file with the data
• https://github.com/timwaters/mapwarper