{"id":"https://data.mapsnap.org/runs/v2.0/iiif/chronoscope/sanborn00374_003.keymap.iiif.json","type":"AnnotationPage","@context":["http://www.w3.org/ns/anno.jsonld"],"label":"Alameda, California | 1950 | key map | mapsnap generated fit (2026-10-17)","creator":{"type":"Software","name":"mapsnap","homepage":"https://mapsnap.org"},"rights":"https://opendatacommons.org/licenses/odbl/1-0/","metadata":[{"label":"generated","value":"2026-10-17"},{"label":"run","value":"corpus-v2"}],"items":[{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000L/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Alameda, California | 1950 | sanborn00374_003 p0L","metadata":[{"label":"streets","value":"52"},{"label":"intersections","value":"116"}],"created":"2026-10-17T01:56:11Z","modified":"2026-10-17T01:56:11Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000L/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000L","type":"ImageService3","width":1624,"height":1949},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"0.0,1949.0 0.0,0.0 1624.0,0.0 1624.0,1949.0 0.0,1949.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000L/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[556.1,1720.8],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-122.2860078,37.7726015]}},{"type":"Feature","properties":{"resourceCoords":[1520.2,1581.2],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-122.2622786,37.7658982]}}]}},{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000R/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Alameda, California | 1950 | sanborn00374_003 p0R","metadata":[{"label":"streets","value":"80"},{"label":"intersections","value":"253"}],"created":"2026-10-17T01:56:11Z","modified":"2026-10-17T01:56:11Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000R/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000R","type":"ImageService3","width":1662,"height":1949},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"0.0,1949.0 0.0,0.0 1662.0,0.0 1662.0,1949.0 0.0,1949.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd436m:g4364m:g4364am:g4364am_g003741950:00374_1950-0000R/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[999.1,1649.2],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-122.242965,37.7554744]}},{"type":"Feature","properties":{"resourceCoords":[595.4,1195.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-122.2461963,37.7672175]}}]}}]}