iTunesMeta

Moving files between iTunes libraries is fraught with potential data loss because only the music files that may be transfered, yet a considerable amount of the data pertaining to your library is not stored in the music files themselves.

This data, which must be transferred by some other mechanism, I call "metadata".

Extraction

This project currently extracts an iTunes library into a json file, each line a single document, corresponding to a music track in the iTunes library.

itunes-meta extract

Run itunes-meta --help to show all options.

Schema

The following properties are pulled directly (while formatting dates as ISO strings) from the ScriptingBridge's ITunesTrack representation:

• playedCount
  • int: Defaults to zero
• playedDate
  • unicode: ISO-8601 format without microseconds or timezone
• skippedCount
  • int: Defaults to zero
• skippedDate
  • unicode: ISO-8601 format without microseconds or timezone
• rating
  • int: iTunes' internal representation is the number of stars * 20, so the range of rating is 0 to 100, inclusive
• dateAdded
  • unicode: ISO-8601 format without microseconds or timezone
• modificationDate
  • unicode: ISO-8601 format without microseconds or timezone

The playlists property is not a feature of the track directly, but of the playlists it is in.

• playlists
  • dict(unicode -> int): Mapping from playlist name to index of the track in the corresponding playlist.

A few other fields are extracted to be used to link the music data back to the file in the other library.

(WXYZ) denotes an ID3v2 tag.

• album (TALB)
• artist (TPE1)
• bitRate (property of the audio encoding)
• duration (property of the audio encoding)
• name (TIT2)
• persistentID
  • I'm not sure if this is actually persisted inside the MP3; it is not in embedded plaintext, at least, and doesn't show up in IDv3
• size (file size)
• year (TYER)

Ignored metadata:

Rare or not very useful variables include:

• bookmark
• bookmarkable
• category
• compilation
• databaseID
• enabled
• EQ
• finish
• gapless
• grouping
• id
• index
• iTunesU
• kind
• longDescription
• lyrics
• objectDescription
• podcast
• releaseDate
• sampleRate
• seasonNumber
• show
• shufflable
• sortAlbum
• sortAlbumArtist
• sortArtist
• sortComposer
• sortName
• sortShow
• time (derivative of duration)
• unplayed (same as playedCount == 0)
• videoKind
• volumeAdjustment

The following are (usually?) stored in the MP3's IDv3 (v1 and/or v2) database.

• bpm (TBPM)
• comment (COMM)
• composer (TCOM)
• discCount (TPOS)
• discNumber (TPOS)
• genre
• trackCount (TRCK)
• trackNumber (TRCK)

Helpful links

• http://www.mugginsoft.com/html/kosmictask/ScriptingBridgeDox/Apple/iTunes/OS-X-10.7/iTunes-10.6.1/html/interfacei_tunes_playlist.html
• http://stackoverflow.com/questions/12964766/create-playlist-in-itunes-with-python-and-scripting-bridge
• http://stackoverflow.com/questions/12971306/how-to-add-a-track-to-an-itunes-playlist-using-python-and-scripting-bridge

License

Copyright © 2013–2014 Christopher Brown. MIT Licensed.