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# Info String Keys

Key values of properties to get and set using Audio File Services functions and provide a common way to get the same information out of several different kinds of files.

## Topics

### Constants

[`var kAFInfoDictionary_Artist: String`](/documentation/AudioToolbox/kAFInfoDictionary_Artist)

An artist.

[`var kAFInfoDictionary_Album: String`](/documentation/AudioToolbox/kAFInfoDictionary_Album)

An album.

[`var kAFInfoDictionary_Tempo: String`](/documentation/AudioToolbox/kAFInfoDictionary_Tempo)

A tempo.

[`var kAFInfoDictionary_KeySignature: String`](/documentation/AudioToolbox/kAFInfoDictionary_KeySignature)

A key signature.

[`var kAFInfoDictionary_TimeSignature: String`](/documentation/AudioToolbox/kAFInfoDictionary_TimeSignature)

A time signature.

[`var kAFInfoDictionary_TrackNumber: String`](/documentation/AudioToolbox/kAFInfoDictionary_TrackNumber)

A track number.

[`var kAFInfoDictionary_Year: String`](/documentation/AudioToolbox/kAFInfoDictionary_Year)

A year.

[`var kAFInfoDictionary_Composer: String`](/documentation/AudioToolbox/kAFInfoDictionary_Composer)

A composer.

[`var kAFInfoDictionary_Lyricist: String`](/documentation/AudioToolbox/kAFInfoDictionary_Lyricist)

A lyricist.

[`var kAFInfoDictionary_Genre: String`](/documentation/AudioToolbox/kAFInfoDictionary_Genre)

A genre.

[`var kAFInfoDictionary_Title: String`](/documentation/AudioToolbox/kAFInfoDictionary_Title)

A title.

[`var kAFInfoDictionary_RecordedDate: String`](/documentation/AudioToolbox/kAFInfoDictionary_RecordedDate)

A recorded date.

[`var kAFInfoDictionary_Comments: String`](/documentation/AudioToolbox/kAFInfoDictionary_Comments)

Comments.

[`var kAFInfoDictionary_Copyright: String`](/documentation/AudioToolbox/kAFInfoDictionary_Copyright)

Copyright.

[`var kAFInfoDictionary_SourceEncoder: String`](/documentation/AudioToolbox/kAFInfoDictionary_SourceEncoder)

A source encoder.

[`var kAFInfoDictionary_EncodingApplication: String`](/documentation/AudioToolbox/kAFInfoDictionary_EncodingApplication)

An encoding application.

[`var kAFInfoDictionary_NominalBitRate: String`](/documentation/AudioToolbox/kAFInfoDictionary_NominalBitRate)

A nominal bit rate.

[`var kAFInfoDictionary_ChannelLayout: String`](/documentation/AudioToolbox/kAFInfoDictionary_ChannelLayout)

A channel layout.

[`var kAFInfoDictionary_ApproximateDurationInSeconds: String`](/documentation/AudioToolbox/kAFInfoDictionary_ApproximateDurationInSeconds)

An approximate duration in seconds.

[`var kAFInfoDictionary_SourceBitDepth: String`](/documentation/AudioToolbox/kAFInfoDictionary_SourceBitDepth)

The bit depth of the source audio stream.

[`var kAFInfoDictionary_ISRC: String`](/documentation/AudioToolbox/kAFInfoDictionary_ISRC)

An International Standard Recording Code.

[`var kAFInfoDictionary_SubTitle: String`](/documentation/AudioToolbox/kAFInfoDictionary_SubTitle)

A subtitle.


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