MetadataExtended

A CityJSON Extension to store ISO19115-compliant metadata, extends the few metadata properties of the core. Works with CityJSON v1.1 and v2.0.

The CityJSON core "metadata" has those 6 properties (see specifications for more details:

• geographicalExtent
• identifier
• pointOfContact
• referenceDate
• referenceSystem
• title

and the MetadataExtended Extension adds several ISO19115-compliant properties, those are documented in the paper A metadata ADE for CityGML.

Integrated in cjio

The easiest way to use the MetadataExtended is by using the software cjio. Those 4 operators are related:

metadata_create   Add the +metadata-extended properties.
metadata_get      Shows the metadata and +metadata-extended of this dataset.
metadata_remove   Remove the +metadata-extended properties.
metadata_update   Update the +metadata-extended.

and most operators (eg subset, lod_filter, etc.) will update the "+metadata-extended" property.

If the "+metadata-extended" is not present in the file, then nothing will be done. But if it is present then it'll be automatically updated.

To start use the "+metadata-extended":

cjio myfile.city.json metadata_create save myfile.city.json

To remove the "+metadata-extended" property (but keep "metadata"):

cjio myfile.city.json metadata_remove save myfile.city.json

Example of a CityJSON file using the +metadata-extended

  {
    "type": "CityJSON",
    "version": "2.0",
    "extensions":
    {
        "Metadata-Extended":
        {
            "url": "https://raw.githubusercontent.com/cityjson/metadata-extended/0.6/metadata-extended.ext.json",
            "version": "0.6"
        }        
    },
    "metadata":
    {
      "geographicalExtent": [ 84710.1, 446846.0, -5.3, 84757.1, 446944.0, 40.9 ],
      "identifier": "eaeceeaa-3f66-429a-b81d-bbc6140b8c1c",
      "pointOfContact": {
        "contactName": "3D geoinformation group, Delft University of Technology",
        "contactType": "organization",
        "role": "owner",
        "phone": "+31-6666666666",
        "emailAddress": "[email protected]",
        "website": "https://3d.bk.tudelft.nl",
        "address": {
          "details": "Julianalaan 134, Delft 2628BL, the Netherlands"
        }
      },
      "referenceDate": "1977-02-28",
      "referenceSystem": "https://www.opengis.net/def/crs/EPSG/0/2355",
      "title": "Buildings in LoD2.3 of Chibougamau, Québec"
    },
    "+metadata-extended": {
        "isTriangulated": false,
        "metadataDateStamp": "2021-07-12",
        "datasetTopicCategory": "geoscientificInformation",
        "spatialRepresentationType": ["vector"],
        "fileIdentifier": "delft.json",
        "metadataStandard": "ISO 19115 - Geographic Information - Metadata",
        "metadataStandardVersion": "ISO 19115:2014(E)",
        "metadataCharacterSet": "UTF-8",
        "datasetCharacterSet": "UTF-8",
        "textures": "absent",
        "materials": "absent"
    },
    "CityObjects": {},
    "vertices": [],
    "transform": {
      "scale": [1.0, 1.0, 1.0],
      "translate": [0.0, 0.0, 0.0]
    }
  }