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  "title" : "Metadata Identifier Keyspaces"
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# Metadata Identifier Keyspaces

Constants that describe metadata identifier keyspaces.

## Topics

### Constants

[`let kCMMetadataKeySpace_QuickTimeUserData: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_QuickTimeUserData)

Metadata keyspace for QuickTime User Data keys.

[`let kCMMetadataKeySpace_ISOUserData: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_ISOUserData)

Metadata keyspace for MPEG-4 User Data keys.

[`let kCMMetadataKeySpace_QuickTimeMetadata: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_QuickTimeMetadata)

Metadata keyspace for QuickTime Metadata keys.

[`let kCMMetadataKeySpace_iTunes: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_iTunes)

Metadata keyspace for iTunes keys.

[`let kCMMetadataKeySpace_ID3: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_ID3)

Metadata keyspace for ID3 keys.

[`let kCMMetadataKeySpace_Icy: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_Icy)

Metadata keyspace for ShoutCast keys.

[`let kCMMetadataKeySpace_HLSDateRange: CFString`](/documentation/CoreMedia/kCMMetadataKeySpace_HLSDateRange)

Metadata keyspace for HLS DateRange tags.


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