Media Types

Media types (also known as MIME types) indicate the format of a given file or resource artefact, such as application/pdf for a PDF, or image/png for a PNG image.

Media types for common formats are standardised via the IANA media types registery.

Media types are shown:

• in metadata record distribution options, describing the formats a resource can be downloaded as

• in data access systems, when resource artefacts (files) are downloaded

Typically these media types will match. Metadata records may use a local media type where additional context can be provided.

Local Media Types

A set of local media types are registered for use within BAS to provide additional context, or where no suitable IANA media type is available. Wherever possible, local types are based on a broader or cloest matching IANA registered type.

For example the application/pdf+geo local media type is based on the IANA application/pdf type.

These local types are intended for use within metadata records included in the BAS Data Catalogue. They may be used by others for other purposes if useful, but may be changed or removed at any time.

Type	Name
application/pdf+geo	Georeferenced PDF
application/geopackage+sqlite3+zip	Zipped GeoPackage
application/vnd.shp+zip	Zipped Shapefile

Local Media Types (services)

A set of additional local media types are defined to represent services within distribution options.

This approach is known bad practice but cannot be fixed until services (and service bindings) can be used within the BAS metadata ecosystem.

Type	Name
x-service/arcgis+service+feature	Esri ArcGIS Feature Service
x-service/ogc+api+feature	OGC API Features Service
x-service/arcgis+service+tile+vector	Esri ArcGIS Vector Tile Service
x-service/arcgis+layer+feature	Esri ArcGIS Hosted Feature Layer
x-service/arcgis+layer+feature+ogc	Esri ArcGIS Hosted OGC Feature Layer
x-service/arcgis+layer+tile+vector	Esri ArcGIS Hosted Vector Tile Layer