Xattr
Xattr tags are "eXtended ATTRibute" tags, which is a feature of MacOS 10.4 or later. They're like "spotlight comments" in that they are a type of meta tagging facility built into the file system when seen thru the lense of the Mac OS. (they also work on FAT32 volumes with the "._" prefixed sidecar file). For the most fantastic explanation ever, see the Ars Techica article on it.
Anyway I use xattr tags currently on all QuickTime compatible files that do not have the ".mov" extension, and also on zip files so i do not need to open the zip to get at the tagging info. Here is what my xattr looks like:
[oxford:kj/media/bin] davec% xattr -l "Rave On.bin" Rave On.bin com.meta.albm Unknown Album com.meta.arts Buddy Holly com.meta.crdt 2006 com.meta.genr Rock com.meta.name Rave On com.meta.soft kJams Pro 1.0d45r21 com.meta.trak 1 [oxford:kj/media/bin] davec%
Note: It's a very simple format, I'm just using QuickTime “Common Key Format” tag names (from Movies.h) as the keys (prepended with "com.meta."). I've added a few others:
/* kQTMetaDataCommonKeyAuthor = 'auth', kQTMetaDataCommonKeyComment = 'cmmt', kQTMetaDataCommonKeyCopyright = 'cprt', kQTMetaDataCommonKeyDirector = 'dtor', kQTMetaDataCommonKeyDisplayName = 'name', kQTMetaDataCommonKeyInformation = 'info', kQTMetaDataCommonKeyKeywords = 'keyw', kQTMetaDataCommonKeyProducer = 'prod', kQTMetaDataCommonKeyAlbum = 'albm', kQTMetaDataCommonKeyArtist = 'arts', kQTMetaDataCommonKeyArtwork = 'artw', kQTMetaDataCommonKeyChapterName = 'chap', kQTMetaDataCommonKeyComposer = 'comp', kQTMetaDataCommonKeyDescription = 'desc', kQTMetaDataCommonKeyGenre = 'genr', kQTMetaDataCommonKeyOriginalFormat = 'orif', kQTMetaDataCommonKeyOriginalSource = 'oris', kQTMetaDataCommonKeyPerformers = 'perf', kQTMetaDataCommonKeySoftware = 'soft', kQTMetaDataCommonKeyWriter = 'wrtr' */ enum { CM_Key_TESTAMUNDO = 'tmdo', // bool CM_Key_NONE = 'xxxx', CM_Key_ALL = '****', CM_Key_NAME = kQTMetaDataCommonKeyDisplayName, // 'name', CM_Key_ARTIST = kQTMetaDataCommonKeyArtist, // 'arts', CM_Key_ALBUM = kQTMetaDataCommonKeyAlbum, // 'albm', CM_Key_GENRE = kQTMetaDataCommonKeyGenre, // 'genr', CM_Key_COMMENT = kQTMetaDataCommonKeyComment, // 'cmmt', CM_Key_KEYWORDS = kQTMetaDataCommonKeyKeywords, // 'keyw' CM_Key_SOFTWARE = kQTMetaDataCommonKeySoftware, // 'soft' CM_Key_WRITER = kQTMetaDataCommonKeyWriter, // 'wrtr' CM_Key_COPYRIGHT = kQTMetaDataCommonKeyCopyright, // 'cprt' CM_Key_SORT_NAME = 'Snam', CM_Key_SORT_ARTIST = 'Sart', CM_Key_SORT_ALBUM = 'Salb', CM_Key_CUSTOM = 'cust', CM_Key_CUSTOM_NUM = 'cstN', CM_Key_SUB_GENRE = 'SUBg', // string CM_Key_SwitchableAlbum_Dict = 'LDct', // list of albums for popup menu, including default index value CM_Key_SwitchableSongs_Dict = 'SDct', // list of songs for popup menu, including default index value CM_Key_PLI_INDEX = 'piIx', // int, same as PLI_ID CM_Key_SORT_INDEX = 'stIx', // int CM_Key_DUET = 'Duet', // bool CM_Key_DUET_STR = 'DueS', // STR CM_Key_BITRATE = 'bRat', // string CM_Key_DOWNLOAD = 'dl ', // bool CM_Key_STREAM = 'strm', // bool CM_Key_TIER = 'Tier', // string CM_Key_TWIRLED = 'Twrl', // bool CM_Key_LANGUAGE = 'Lang', // string CM_Key_KEY = 'Keyc', // string CM_Key_KEY_CHANGES = 'KeCH', // string CM_Key_VOLUME = 'volm', // float CM_Key_LABEL = 'colr', // integer CM_Key_RATING = 'rtng', // integer CM_Key_GRAPHIC_CHANNELS = 'gChn', // integer CM_Key_COOP_THREAD = 'Coop', // bool, must be extracted on a cooperative thread CM_Key_DEMUX_MPEG = 'Muxd', // bool, must be demuxed CM_Key_PIPE_TYPE = 'mPip', // int MetaPipeType CM_Key_PUSH_LEVEL = 'mPsh', // int meta push level CM_Key_SONG_ID = 'soID', // int CM_Key_SINGER_ID = 'siID', // int CM_Key_PLAYLIST_ID = 'plID', // int CM_Key_SINGER_PLI = 'sPLI', // int CM_Key_TEMP_PLID = 'sTid', // long used for music stores and CDs CM_Key_FORMAT = 'Frmt', // string CM_Key_COPY_META_FLAGS = 'cMfl', // int, based on CM_Key_FORMAT CM_Key_SOURCE = 'SRCE', CM_Key_TRACK = 'trak', // int CM_Key_YEAR = 'cryr', // int (NOT date) CM_Key_ORIG_YEAR = 'ORyr', // int (NOT date) CM_Key_START = 'strt', // int sectors CM_Key_DURATION = 'drtn', // int sectors CM_Key_PREVIEW_DURATION = 'pDrn', // int sectors CM_Key_SKIP_SILENCE_END = 'ssNd', // int subcodes (records) CM_Key_TRIM_START = 'Tsrt', // int subcodes CM_Key_TRIM_END = 'Tend', // int subcodes CM_Key_TIMES_SUNG = 'tsng', // integer, times sung CM_Key_SIZE = 'SIZE', // int CM_Key_DATE_LAST_SUNG = 'Date', // date CM_Key_DATE_ADDED = 'DAdd', // date CM_Key_PLAY_ME = 'PLME', // bool CM_Key_PITCH = 'PICH', // int CM_Key_CENTS = 'cent', // float CM_Key_BPM = 'bpm ', // int CM_Key_TEMPO = 'TMPO', // float CM_Key_MISSING = 'Msng', // bool CM_Key_NO_CDG = 'nCDG', // bool CM_Key_IGNORE_RS_ERR = 'igRS', // bool ignore reed-solomon error correction CM_Key_SINGER = 'SNGR', // string CM_Key_SINGER_NICK = 'nick', // string CM_Key_SINGER_PASS = 'Spas', // string CM_Key_SINGER_SMS_ENABLE = 'SmsB', // bool CM_Key_SINGER_SMS_REGION = 'SmsR', // string CM_Key_SINGER_SMS_CARRIER = 'SmsC', // string CM_Key_SINGER_SMS_NUMBER = 'SmsN', // string CM_Key_BIO = 'Bio ', // string CM_Key_PRESENT = 'PSNT', // bool CM_Key_PLI_SORT_TO_TOP = 'pStt', // bool // not stored in PLI, but directly in Singer or PlayList CM_Key_SINGER_IS_KJ = 'sgKJ', // bool CM_Key_PRODUCER_DICT = 'prod', // dictinary CM_Key_MEDIA_STREAM = 'meSt', // dictinary CM_Key_SONGWRITER = 'swrt', // string CM_Key_GENDER = 'gndr', // string CM_Key_COMPOSER = 'cpsr', // string CM_Key_PUBLISHER = 'pbls', // string CM_Key_ORIGINAL_PUBLISHER = 'ORpb', // string CM_Key_ACTUAL_DURATION = 'aDur', // string CM_Key_RENDITION = 'rdtn', // string CM_Key_BACKING_VOCALS = 'bVoc', // bool CM_Key_LEAD_VOCALS = 'lVoc', // bool (center channel lead vocals) CM_Key_VOCAL_CHANNEL = 'vChn', // integer CM_Key_COLOR_BACKGROUND = 'cBak', // string CM_Key_EXPLICIT = 'Expl', // bool, parental advisory lyrics CM_Key_SONG_SLIP = 'Slip', // int CM_Key_CAVS_TYPE = 'cavT', // int CM_Key_CAVS_DATA = 'cavD', // cfdata CM_Key_FSRef_0_AUDIO = 'Sfs0', // CData::ValType_FILEREF CM_Key_FSRef_1_VIDEO = 'Sfs1', CM_Key_FSRef_2_ZIP = 'Sfs2', CM_Key_FSRef_3_AUD_CACHE = 'Sfs3', CM_Key_FSRef_4_VID_CACHE = 'Sfs4', CM_Key_FSRef_5_META = 'Sfs5', CM_Key_FSRef_6_AUD_CD = 'Sfs6', CM_Key_FSRef_7_VID_CD = 'Sfs7', CM_Key_FSRef_8_UNPACK = 'Sfs8', CM_Key_FSRef_9_TEMP_ZIP = 'Sfs9', CM_Key_FSRef_10_PROJ = 'Sf10', CM_Key_FSRef_11_LAUNCH = 'Sf11', // store related CM_Key_STORE_NAME = 'StrN', // string CM_Key_STORE_NUM_SONGS = 'SNmS', // long CM_Key_STORE_URL = 'sURL', // string CM_Key_STORE_ID = 'stor', // long CM_Key_SAMPLE = 'Smpl', // string CM_Key_STREAMING_URL = 'stmR', // string CM_Key_PRICE_USD = 'pUSD', // string CM_Key_PRICE_USD_FREE = 'USDf', CM_Key_PRICE_USD_STREAM = 'USDs', CM_Key_PRICE_USD_BUY_STREAM = 'USDb', CM_Key_PURCHASE_CODE = 'pTRI', // string CM_Key_PURCHASED = 'purc', // bool CM_Key_MUST_COMPLETE_PURCHASE = 'CplP', // bool CM_Key_PLAY_AFTER_PURCHASE = 'PlaP', // bool CM_Key_RECENT = 'Rcnt', // bool CM_Key_STORE_SONG_ID = 'SsID', // long CM_Key_STORE_CUSTOM_ID = 'ScID', // long CM_Key_SONG_PAGE_URL = 'spRL', // string CM_Key_SONG_NO_SYNCED_LYRICS = 'sNSL', // bool CM_Key_SORT_INDEX_ROTATION = 'rotn', CM_Key_ALPHA_LABEL = 'ALFA' };
For compatibility with 10.3 I'm using a standard plist sidecar file (XML) with the ".xattr" extension, which can be easily edited with any text editor, XML editor, or plist editor.