{"id":"https://data.mapsnap.org/runs/v1.3/iiif/chronoscope/sanborn02598_003.keymap.iiif.json","type":"AnnotationPage","@context":["http://www.w3.org/ns/anno.jsonld"],"label":"Centerville, Iowa | 1893 | key map | mapsnap generated fit (2026-09-22)","creator":{"type":"Software","name":"mapsnap","homepage":"https://mapsnap.org"},"rights":"https://opendatacommons.org/licenses/odbl/1-0/","metadata":[{"label":"generated","value":"2026-09-22"},{"label":"run","value":"corpus-v1"}],"items":[{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd415m:g4154m:g4154cm:g025981893:02598_1893-0001__1/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Centerville, Iowa | 1893 | sanborn02598_003 p1 [1]","metadata":[{"label":"streets","value":"16"},{"label":"intersections","value":"21"},{"label":"split_canvas_x","value":"0.0"},{"label":"split_canvas_y","value":"0.0"},{"label":"split_canvas_w","value":"6878.4"},{"label":"split_canvas_h","value":"6001.8"}],"created":"2026-09-22T17:30:58Z","modified":"2026-09-22T17:30:58Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd415m:g4154m:g4154cm:g025981893:02598_1893-0001__1/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd415m:g4154m:g4154cm:g025981893:02598_1893-0001","type":"ImageService3","width":1613,"height":1913},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"1613,0.0 -0.0,0.0 0.0,1500.5 1156.6,1500.5 1613,1500.5 1613,0.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd415m:g4154m:g4154cm:g025981893:02598_1893-0001__1/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[566.3,698.2],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-92.8741994,40.7318002]}},{"type":"Feature","properties":{"resourceCoords":[566.3,290.8],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-92.8742155,40.7377422]}}]}}]}