{"id":"https://data.mapsnap.org/runs/v1.3/iiif/chronoscope/sanborn03907_001.keymap.iiif.json","type":"AnnotationPage","@context":["http://www.w3.org/ns/anno.jsonld"],"label":"Alpena, Michigan | 1884 | 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:gmd411m:g4114m:g4114am:g039071884:03907_1884-0001/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Alpena, Michigan | 1884 | sanborn03907_001 p1","metadata":[{"label":"streets","value":"39"},{"label":"intersections","value":"150"}],"created":"2026-09-22T23:44:39Z","modified":"2026-09-22T23:44:39Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd411m:g4114m:g4114am:g039071884:03907_1884-0001/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd411m:g4114m:g4114am:g039071884:03907_1884-0001","type":"ImageService3","width":1628,"height":1927},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1927.0 -0.0,-0.0 1628.0,0.0 1628.0,1927.0 -0.0,1927.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd411m:g4114m:g4114am:g039071884:03907_1884-0001/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[993.5,1138.7],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-83.4286187,45.0667945]}},{"type":"Feature","properties":{"resourceCoords":[428.1,796.1],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-83.4423957,45.0651875]}}]}}]}