many other aspects of the media object. The Instantiation metadata includes the location of the physical or digital media object, which in the case of a streaming media file can be its full URL. In PBCore there can be many Instantiations for the same AV asset, all of which share the same Intellectual Content metadata. Extension allows for the integration of data from other metadata schema, such as EAD and PREMIS. PBCore provides an XSD allowing validation of PBCore XML records. PBCore XML can be used to exchange detailed metadata about media assets, and optionally the media assets themselves, among systems configured for the PBCore standard. The schema is used by organizations within the public media community as well as in archives and libraries across the world. Elements Although a PBCore record potentially contains a great many elements, the only required elements are any one of the root elements, pbcoreIdentifier, and pbcoreTitle Root Elements pbcoreDescriptionDocument pbcoreCollection pbcoreInstantiationDocument Intellectual Content pbcoreAssetType pbcoreAssetDate pbcoreIdentifier pbcoreTitle pbcoreSubject pbcoreDescription pbcoreGenre pbcoreRelation pbcoreRelationType pbcoreRelationIdentifier pbcoreCoverage coverage coverageType pbcoreAudienceLevel pbcoreAudienceRating pbcoreAnnotation Intellectual Property pbcoreCreator creator creatorRole pbcoreContributor contributor contributorRole pbcorePublisher publisher publisherRole pbcoreRightsSummary rightsSummary rightsLink rightsEmbedded Extensions pbcoreExtension extensionWrap extensionElement extensionValue extensionAuthorityUsed extensionEmbedded pbcorePart Instantiation pbcoreInstantiation instantiationIdentifier instantiationDate instantiationDimensions instantiationPhysical instantiationDigital instantiationStandard instantiationLocation instantiationMediaType instantiationGenerations instantiationFileSize instantiationTimeStart instantiationDuration instantiationDataRate instantiationColors instantiationTracks instantiationChannelConfiguration instantiationLanguage instantiationAlternativeModes instantiationEssenceTrack essenceTrackType essenceTrackIdentifier essenceTrackStandard essenceTrackEncoding essenceTrackDataRate essenceTrackFrameRate essenceTrackPlaybackSpeed essenceTrackSamplingRate essenceTrackBitDepth essenceTrackFrameSize essenceTrackAspectRatio essenceTrackTimeStart essenceTrackDuration essenceTrackLanguage essenceTrackAnnotation essenceTrackExtension instantiationRelation instantiationRelationType instantiationRelationIdentifier instantiationRights rightsSummary rightsLink rightsEmbedded instantiationAnnotation instantiationPart instantiationExtension See also American Archive of Public Broadcasting Dublin Core Metadata standards References External links Official website User community website Dublin Core website Library science Metadata standards Public broadcasting in the United States