IIIF/iiif-stories

I want to georeference a IIIF image of a map 

glenrobson opened this issue · 4 comments

glenrobson commented

Description

I want to georeference a IIIF image of a map

12-votes in Stanford maps meeting

Variation(s)

(do you know of, or can you imagine, similar use cases?)

Proposed Solutions

(any ideas about how your use case might be supported)

Additional Background

(more about your perspective, existing work, etc. goes here.)

mejackreed commented

The needed information for providing georeferencing of an image:

  • mask of image (area to be georef, can be whole image)
  • control points related to geographic space + pixel coordinate space

Masking Annotation

targets: svg or whole canvas
body: geojson feature collection

FeatureCollection contains points, the points have properties these properties contain the pixel space coordinates.

{
  "id": "http://annotation/id",
  "motivation": "georeferencing",
  "target": "https://example.com/manifest/123/canvas/123#xywh=50,50,100,100",
  "body": {
    "type": "FeatureCollection",
    "features": [
      {
        "type": "Feature",
        "properties": {
          "transformationType": "affine",
          "x": 300,
          "y": 400
        },
        "geometry": {
          "type": "Point",
          "coordinates": [
            -2.109375,
            13.923403897723347
          ]
        }
      },
      {
        "type": "Feature",
        "properties": {
          "transformationType": "affine",
          "x": 100,
          "y": 200
        },
        "geometry": {
          "type": "Point",
          "coordinates": [
            11.25,
            21.616579336740603
          ]
        }
      }
    ]
  }
}
abrin commented

to clarify, geometry and control points are at the canvas points for the image. (was the pixel points for the full image)

glenrobson commented

Control points would be for the full image or rather the canvas dimensions.