module ID3.Parser.NativeFrames where -- {-- IMPORTS import ID3.Parser.UnSync import ID3.Parser.General import ID3.Type.FrameInfo import Text.ParserCombinators.Poly.StateParser (Parser) {-import ID3.Type.Frame-} ----} --frameInfo :: String -> TagParser (FrameName, FrameInfo) ---- {-- 4.2. Text information frames -- The text information frames are often the most important frames, -- containing information like artist, album and more. There may only be -- one text information frame of its kind in an tag. All text -- information frames supports multiple strings, stored as a null -- separated list, where null is reperesented by the termination code -- for the charater encoding. All text frame identifiers begin with "T". -- Only text frame identifiers begin with "T", with the exception of the -- "TXXX" frame. All the text information frames have the following -- format: -- <Header for 'Text information frame', ID: "T000" - "TZZZ", -- excluding "TXXX" described in 4.2.6.> -- Text encoding $xx -- Information <text string(s) according to encoding> textInfo :: String -> TagParser FrameInfo textInfo _ = do enc0 <- parseEncoding info <- parseString enc0 return $ Text enc0 info ---- {-- 4.3. URL link frames -- With these frames dynamic data such as webpages with touring -- information, price information or plain ordinary news can be added to -- the tag. There may only be one URL [URL] link frame of its kind in an -- tag, except when stated otherwise in the frame description. If the -- text string is followed by a string termination, all the following -- information should be ignored and not be displayed. All URL link -- frame identifiers begins with "W". Only URL link frame identifiers -- begins with "W", except for "WXXX". All URL link frames have the -- following format: -- <Header for 'URL link frame', ID: "W000" - "WZZZ", excluding "WXXX" -- described in 4.3.2.> -- URL <text string> urlInfo :: String -> Parser St Token FrameInfo urlInfo _ = do url0 <- parseString 0 return $ URL url0 ---- {-- 4.1. Unique file identifier -- This frame's purpose is to be able to identify the audio file in a -- database, that may provide more information relevant to the content. -- Since standardisation of such a database is beyond this document, all -- UFID frames begin with an 'owner identifier' field. It is a null- -- terminated string with a URL [URL] containing an email address, or a -- link to a location where an email address can be found, that belongs -- to the organisation responsible for this specific database -- implementation. Questions regarding the database should be sent to -- the indicated email address. The URL should not be used for the -- actual database queries. The string -- "http://www.id3.org/dummy/ufid.html" should be used for tests. The -- 'Owner identifier' must be non-empty (more than just a termination). -- The 'Owner identifier' is then followed by the actual identifier, -- which may be up to 64 bytes. There may be more than one "UFID" frame -- in a tag, but only one with the same 'Owner identifier'. -- <Header for 'Unique file identifier', ID: "UFID"> -- Owner identifier <text string> $00 -- Identifier <up to 64 bytes binary data> frameInfo :: String -> Parser St Token FrameInfo frameInfo "UFID" = do ownerId0 <- parseString 0 identifier <- many' anyWord8 return $ UFID ownerId0 identifier ---- --} ---- {-- 4.2.1. Identification frames -- TIT1 -- The 'Content group description' frame is used if the sound belongs to -- a larger category of sounds/music. For example, classical music is -- often sorted in different musical sections (e.g. "Piano Concerto", -- "Weather - Hurricane"). frameInfo "TIT1" = textInfo "Content group description" -- TIT2 -- The 'Title/Songname/Content description' frame is the actual name of -- the piece (e.g. "Adagio", "Hurricane Donna"). frameInfo "TIT2" = textInfo "Title" -- TIT3 -- The 'Subtitle/Description refinement' frame is used for information -- directly related to the contents title (e.g. "Op. 16" or "Performed -- live at Wembley"). frameInfo "TIT3" = textInfo "Subtitle" -- TALB -- The 'Album/Movie/Show title' frame is intended for the title of the -- recording (or source of sound) from which the audio in the file is -- taken. frameInfo "TALB" = textInfo "Album" -- TOAL -- The 'Original album/movie/show title' frame is intended for the title -- of the original recording (or source of sound), if for example the -- music in the file should be a cover of a previously released song. frameInfo "TOAL" = textInfo "Original album" -- TRCK -- The 'Track number/Position in set' frame is a numeric string -- containing the order number of the audio-file on its original -- recording. This MAY be extended with a "/" character and a numeric -- string containing the total number of tracks/elements on the original -- recording. E.g. "4/9". frameInfo "TRCK" = textInfo "Track number" -- TPOS -- The 'Part of a set' frame is a numeric string that describes which -- part of a set the audio came from. This frame is used if the source -- described in the "TALB" frame is divided into several mediums, e.g. a -- double CD. The value MAY be extended with a "/" character and a -- numeric string containing the total number of parts in the set. E.g. -- "1/2". frameInfo "TPOS" = textInfo "Part of a set" -- TSST -- The 'Set subtitle' frame is intended for the subtitle of the part of -- a set this track belongs to. frameInfo "TSST" = textInfo "Set subtitle" -- TSRC -- The 'ISRC' frame should contain the International Standard Recording -- Code [ISRC] (12 characters). frameInfo "TSRC" = textInfo "International Standard Recording Code [ISRC]" ---- --} ---- {-- 4.2.2. Involved persons frames -- TPE1 -- The 'Lead artist/Lead performer/Soloist/Performing group' is -- used for the main artist. frameInfo "TPE1" = textInfo "Lead artist" -- TPE2 -- The 'Band/Orchestra/Accompaniment' frame is used for additional -- information about the performers in the recording. frameInfo "TPE2" = textInfo "Accompaniment" -- TPE3 -- The 'Conductor' frame is used for the name of the conductor. frameInfo "TPE3" = textInfo "Conductor" -- TPE4 -- The 'Interpreted, remixed, or otherwise modified by' frame contains -- more information about the people behind a remix and similar -- interpretations of another existing piece. frameInfo "TPE4" = textInfo "Remixed by" -- TOPE -- The 'Original artist/performer' frame is intended for the performer -- of the original recording, if for example the music in the file -- should be a cover of a previously released song. frameInfo "TOPE" = textInfo "Original artist" -- TEXT -- The 'Lyricist/Text writer' frame is intended for the writer of the -- text or lyrics in the recording. frameInfo "TEXT" = textInfo "Text writer" -- TOLY -- The 'Original lyricist/text writer' frame is intended for the -- text writer of the original recording, if for example the music in -- the file should be a cover of a previously released song. frameInfo "TOLY" = textInfo "Original text writer" -- TCOM -- The 'Composer' frame is intended for the name of the composer. frameInfo "TCOM" = textInfo "Composer" -- TMCL -- The 'Musician credits list' is intended as a mapping between -- instruments and the musician that played it. Every odd field is an -- instrument and every even is an artist or a comma delimited list of -- artists. frameInfo "TMCL" = textInfo "Musician credits list" -- TIPL -- The 'Involved people list' is very similar to the musician credits -- list, but maps between functions, like producer, and names. frameInfo "TIPL" = textInfo "Involved people list" -- TENC -- The 'Encoded by' frame contains the name of the person or -- organisation that encoded the audio file. This field may contain a -- copyright message, if the audio file also is copyrighted by the -- encoder. frameInfo "TENC" = textInfo "Encoded by" ---- --} ---- {-- 4.2.3. Derived and subjective properties frames -- TBPM -- The 'BPM' frame contains the number of beats per minute in the -- main part of the audio. The BPM is an integer and represented as a -- numerical string. frameInfo "TBPM" = textInfo "Beats per minute" -- TLEN -- The 'Length' frame contains the length of the audio file in -- milliseconds, represented as a numeric string. frameInfo "TLEN" = textInfo "Length (in milliseconds)" -- TKEY -- The 'Initial key' frame contains the musical key in which the sound -- starts. It is represented as a string with a maximum length of three -- characters. The ground keys are represented with "A","B","C","D","E", -- "F" and "G" and halfkeys represented with "b" and "#". Minor is -- represented as "m", e.g. "Dbm" $00. Off key is represented with an -- "o" only. frameInfo "TKEY" = textInfo "" -- TLAN -- The 'Language' frame should contain the languages of the text or -- lyrics spoken or sung in the audio. The language is represented with -- three characters according to ISO-639-2 [ISO-639-2]. If more than one -- language is used in the text their language codes should follow -- according to the amount of their usage, e.g. "eng" $00 "sve" $00. frameInfo "TLAN" = textInfo "Language" -- TCON -- The 'Content type', which ID3v1 was stored as a one byte numeric -- value only, is now a string. You may use one or several of the ID3v1 -- types as numerical strings, or, since the category list would be -- impossible to maintain with accurate and up to date categories, -- define your own. Example: "21" $00 "Eurodisco" $00 -- You may also use any of the following keywords: -- RX Remix -- CR Cover frameInfo "TCON" = textInfo "Content type" -- TFLT -- The 'File type' frame indicates which type of audio this tag defines. -- The following types and refinements are defined: -- MIME MIME type follows -- MPG MPEG Audio -- /1 MPEG 1/2 layer I -- /2 MPEG 1/2 layer II -- /3 MPEG 1/2 layer III -- /2.5 MPEG 2.5 -- /AAC Advanced audio compression -- VQF Transform-domain Weighted Interleave Vector Quantisation -- PCM Pulse Code Modulated audio -- but other types may be used, but not for these types though. This is -- used in a similar way to the predefined types in the "TMED" frame, -- but without parentheses. If this frame is not present audio type is -- assumed to be "MPG". frameInfo "TFLT" = textInfo "File type" -- TMED -- The 'Media type' frame describes from which media the sound -- originated. This may be a text string or a reference to the -- predefined media types found in the list below. Example: -- "VID/PAL/VHS" $00. frameInfo "TMED" = textInfo "Media type" -- {-- Media types: -- DIG Other digital media -- /A Analogue transfer from media -- ANA Other analogue media -- /WAC Wax cylinder -- /8CA 8-track tape cassette -- CD CD -- /A Analogue transfer from media -- /DD DDD -- /AD ADD -- /AA AAD -- LD Laserdisc -- TT Turntable records -- /33 33.33 rpm -- /45 45 rpm -- /71 71.29 rpm -- /76 76.59 rpm -- /78 78.26 rpm -- /80 80 rpm -- MD MiniDisc -- /A Analogue transfer from media -- DAT DAT -- /A Analogue transfer from media -- /1 standard, 48 kHz/16 bits, linear -- /2 mode 2, 32 kHz/16 bits, linear -- /3 mode 3, 32 kHz/12 bits, non-linear, low speed -- /4 mode 4, 32 kHz/12 bits, 4 channels -- /5 mode 5, 44.1 kHz/16 bits, linear -- /6 mode 6, 44.1 kHz/16 bits, 'wide track' play -- DCC DCC -- /A Analogue transfer from media -- DVD DVD -- /A Analogue transfer from media -- TV Television -- /PAL PAL -- /NTSC NTSC -- /SECAM SECAM -- VID Video -- /PAL PAL -- /NTSC NTSC -- /SECAM SECAM -- /VHS VHS -- /SVHS S-VHS -- /BETA BETAMAX -- RAD Radio -- /FM FM -- /AM AM -- /LW LW -- /MW MW -- TEL Telephone -- /I ISDN -- MC MC (normal cassette) -- /4 4.75 cm/s (normal speed for a two sided cassette) -- /9 9.5 cm/s -- /I Type I cassette (ferric/normal) -- /II Type II cassette (chrome) -- /III Type III cassette (ferric chrome) -- /IV Type IV cassette (metal) -- REE Reel -- /9 9.5 cm/s -- /19 19 cm/s -- /38 38 cm/s -- /76 76 cm/s -- /I Type I cassette (ferric/normal) -- /II Type II cassette (chrome) -- /III Type III cassette (ferric chrome) -- /IV Type IV cassette (metal) ----} -- TMOO -- The 'Mood' frame is intended to reflect the mood of the audio with a -- few keywords, e.g. "Romantic" or "Sad". frameInfo "TMOD" = textInfo "Mood" ---- --} ---- {-- 4.2.4. Rights and license frames -- TCOP -- The 'Copyright message' frame, in which the string must begin with a -- year and a space character (making five characters), is intended for -- the copyright holder of the original sound, not the audio file -- itself. The absence of this frame means only that the copyright -- information is unavailable or has been removed, and must not be -- interpreted to mean that the audio is public domain. Every time this -- field is displayed the field must be preceded with "Copyright " (C) " -- ", where (C) is one character showing a C in a circle. frameInfo "TCOP" = textInfo "Copyright message" -- TPRO -- The 'Produced notice' frame, in which the string must begin with a -- year and a space character (making five characters), is intended for -- the production copyright holder of the original sound, not the audio -- file itself. The absence of this frame means only that the production -- copyright information is unavailable or has been removed, and must -- not be interpreted to mean that the audio is public domain. Every -- time this field is displayed the field must be preceded with -- "Produced " (P) " ", where (P) is one character showing a P in a -- circle. frameInfo "TPRO" = textInfo "Produced notice" -- TPUB -- The 'Publisher' frame simply contains the name of the label or -- publisher. frameInfo "TPUB" = textInfo "Produced notice" -- TOWN -- The 'File owner/licensee' frame contains the name of the owner or -- licensee of the file and it's contents. frameInfo "TOWN" = textInfo "File owner/licensee" -- TRSN -- The 'Internet radio station name' frame contains the name of the -- internet radio station from which the audio is streamed. frameInfo "TRSN" = textInfo "Internet radio station name" -- TRSO -- The 'Internet radio station owner' frame contains the name of the -- owner of the internet radio station from which the audio is -- streamed. frameInfo "TRSO" = textInfo "Internet radio station owner" ---- --} ---- {-- 4.2.5. Other text frames -- TOFN -- The 'Original filename' frame contains the preferred filename for the -- file, since some media doesn't allow the desired length of the -- filename. The filename is case sensitive and includes its suffix. frameInfo "TOFN" = textInfo "Original filename" -- TDLY -- The 'Playlist delay' defines the numbers of milliseconds of silence -- that should be inserted before this audio. The value zero indicates -- that this is a part of a multifile audio track that should be played -- continuously. frameInfo "TDLY" = textInfo "Playlist delay" -- TDEN -- The 'Encoding time' frame contains a timestamp describing when the -- audio was encoded. Timestamp format is described in the ID3v2 -- structure document [ID3v2-strct]. frameInfo "TDEN" = textInfo "Encoding time" -- TDOR -- The 'Original release time' frame contains a timestamp describing -- when the original recording of the audio was released. Timestamp -- format is described in the ID3v2 structure document [ID3v2-strct]. frameInfo "TDOR" = textInfo "Original release time" -- TDRC -- The 'Recording time' frame contains a timestamp describing when the -- audio was recorded. Timestamp format is described in the ID3v2 -- structure document [ID3v2-strct]. frameInfo "TDRC" = textInfo "Recording time" -- TDRL -- The 'Release time' frame contains a timestamp describing when the -- audio was first released. Timestamp format is described in the ID3v2 -- structure document [ID3v2-strct]. frameInfo "TDRL" = textInfo "Release time" -- TDTG -- The 'Tagging time' frame contains a timestamp describing then the -- audio was tagged. Timestamp format is described in the ID3v2 -- structure document [ID3v2-strct]. frameInfo "TDTG" = textInfo "Tagging time" -- TSSE -- The 'Software/Hardware and settings used for encoding' frame -- includes the used audio encoder and its settings when the file was -- encoded. Hardware refers to hardware encoders, not the computer on -- which a program was run. frameInfo "TSSE" = textInfo "Software/Hardware and settings used for encoding" -- TSOA -- The 'Album sort order' frame defines a string which should be used -- instead of the album name (TALB) for sorting purposes. E.g. an album -- named "A Soundtrack" might preferably be sorted as "Soundtrack". frameInfo "TSOA" = textInfo "Album sort order" -- TSOP -- The 'Performer sort order' frame defines a string which should be -- used instead of the performer (TPE2) for sorting purposes. frameInfo "TSOP" = textInfo "Performer sort order" -- TSOT -- The 'Title sort order' frame defines a string which should be used -- instead of the title (TIT2) for sorting purposes. frameInfo "TSOT" = textInfo "Title sort order" ---- --} frameInfo "TCMP" = do _ <- parseEncoding -- XXX: Is the encoding really not used here?? f <- parseNumber return $ TCMP (f == 1) ---- {-- 4.2.6. User defined text information frame -- This frame is intended for one-string text information concerning the -- audio file in a similar way to the other "T"-frames. The frame body -- consists of a description of the string, represented as a terminated -- string, followed by the actual string. There may be more than one -- "TXXX" frame in each tag, but only one with the same description. -- <Header for 'User defined text information frame', ID: "TXXX"> -- Text encoding $xx -- Description <text string according to encoding> $00 (00) -- Value <text string according to encoding> frameInfo "TXXX" = do enc0 <- parseEncoding descr0 <- parseString enc0 value0 <- parseString enc0 return $ TXXX enc0 descr0 value0 ---- --} }}} ---- {-- 4.3.1. URL link frames - details -- WCOM -- The 'Commercial information' frame is a URL pointing at a webpage -- with information such as where the album can be bought. There may be -- more than one "WCOM" frame in a tag, but not with the same content. frameInfo "WCOM" = urlInfo "Commercial information" -- WCOP -- The 'Copyright/Legal information' frame is a URL pointing at a -- webpage where the terms of use and ownership of the file is -- described. frameInfo "WCOP" = urlInfo "Copyright/Legal information" -- WOAF -- The 'Official audio file webpage' frame is a URL pointing at a file -- specific webpage. frameInfo "WOAF" = urlInfo "Official audio file webpage" -- WOAR -- The 'Official artist/performer webpage' frame is a URL pointing at -- the artists official webpage. There may be more than one "WOAR" frame -- in a tag if the audio contains more than one performer, but not with -- the same content. frameInfo "WOAR" = urlInfo "Official artist webpage" -- WOAS -- The 'Official audio source webpage' frame is a URL pointing at the -- official webpage for the source of the audio file, e.g. a movie. frameInfo "WOAS" = urlInfo "Official audio source webpage" -- WORS -- The 'Official Internet radio station homepage' contains a URL -- pointing at the homepage of the internet radio station. frameInfo "WORS" = urlInfo "Official Internet radio station homepage" -- WPAY -- The 'Payment' frame is a URL pointing at a webpage that will handle -- the process of paying for this file. frameInfo "WPAY" = urlInfo "Payment" -- hahaha! LOL!!! :D -- WPUB -- The 'Publishers official webpage' frame is a URL pointing at the -- official webpage for the publisher. frameInfo "WPUB" = urlInfo "Publishers official webpage" ---- --} ---- {-- 4.3.2. User defined URL link frame -- This frame is intended for URL [URL] links concerning the audio file -- in a similar way to the other "W"-frames. The frame body consists -- of a description of the string, represented as a terminated string, -- followed by the actual URL. The URL is always encoded with ISO-8859-1 -- [ISO-8859-1]. There may be more than one "WXXX" frame in each tag, -- but only one with the same description. -- <Header for 'User defined URL link frame', ID: "WXXX"> -- Text encoding $xx -- Description <text string according to encoding> $00 (00) -- URL <text string> frameInfo "WXXX" = do enc0 <- parseEncoding descr0 <- parseString enc0 url0 <- parseString 0 -- URLs are always encoded in ISO-8859-1 (I think) return $ WXXX enc0 descr0 url0 ---- --} }}} ---- {-- 4.4. Music CD identifier -- This frame is intended for music that comes from a CD, so that the CD -- can be identified in databases such as the CDDB [CDDB]. The frame -- consists of a binary dump of the Table Of Contents, TOC, from the CD, -- which is a header of 4 bytes and then 8 bytes/track on the CD plus 8 -- bytes for the 'lead out', making a maximum of 804 bytes. The offset -- to the beginning of every track on the CD should be described with a -- four bytes absolute CD-frame address per track, and not with absolute -- time. When this frame is used the presence of a valid "TRCK" frame is -- REQUIRED, even if the CD's only got one track. It is recommended that -- this frame is always added to tags originating from CDs. There may -- only be one "MCDI" frame in each tag. -- <Header for 'Music CD identifier', ID: "MCDI"> -- CD TOC <binary data> frameInfo "MCDI" = do _ <- sizeGet tocData0 <- many' anyWord8 return $ MCDI tocData0 ---- --} ---- {-- TODO: 4.5. Event timing codes -- This frame allows synchronisation with key events in the audio. The -- header is: -- <Header for 'Event timing codes', ID: "ETCO"> -- Time stamp format $xx -- Where time stamp format is: -- $01 Absolute time, 32 bit sized, using MPEG [MPEG] frames as unit -- $02 Absolute time, 32 bit sized, using milliseconds as unit -- Absolute time means that every stamp contains the time from the -- beginning of the file. -- Followed by a list of key events in the following format: -- Type of event $xx -- Time stamp $xx (xx ...) -- The 'Time stamp' is set to zero if directly at the beginning of the -- sound or after the previous event. All events MUST be sorted in -- chronological order. The type of event is as follows: -- $00 padding (has no meaning) -- $01 end of initial silence -- $02 intro start -- $03 main part start -- $04 outro start -- $05 outro end -- $06 verse start -- $07 refrain start -- $08 interlude start -- $09 theme start -- $0A variation start -- $0B key change -- $0C time change -- $0D momentary unwanted noise (Snap, Crackle & Pop) -- $0E sustained noise -- $0F sustained noise end -- $10 intro end -- $11 main part end -- $12 verse end -- $13 refrain end -- $14 theme end -- $15 profanity -- $16 profanity end -- $17-$DF reserved for future use -- $E0-$EF not predefined synch 0-F -- $F0-$FC reserved for future use -- $FD audio end (start of silence) -- $FE audio file ends -- $FF one more byte of events follows (all the following bytes with -- the value $FF have the same function) -- Terminating the start events such as "intro start" is OPTIONAL. The -- 'Not predefined synch's ($E0-EF) are for user events. You might want -- to synchronise your music to something, like setting off an explosion -- on-stage, activating a screensaver etc. -- There may only be one "ETCO" frame in each tag. ---- --} ---- {-- TODO: 4.6. MPEG location lookup table -- To increase performance and accuracy of jumps within a MPEG [MPEG] -- audio file, frames with time codes in different locations in the file -- might be useful. This ID3v2 frame includes references that the -- software can use to calculate positions in the file. After the frame -- header follows a descriptor of how much the 'frame counter' should be -- increased for every reference. If this value is two then the first -- reference points out the second frame, the 2nd reference the 4th -- frame, the 3rd reference the 6th frame etc. In a similar way the -- 'bytes between reference' and 'milliseconds between reference' points -- out bytes and milliseconds respectively. -- Each reference consists of two parts; a certain number of bits, as -- defined in 'bits for bytes deviation', that describes the difference -- between what is said in 'bytes between reference' and the reality and -- a certain number of bits, as defined in 'bits for milliseconds -- deviation', that describes the difference between what is said in -- 'milliseconds between reference' and the reality. The number of bits -- in every reference, i.e. 'bits for bytes deviation'+'bits for -- milliseconds deviation', must be a multiple of four. There may only -- be one "MLLT" frame in each tag. -- <Header for 'Location lookup table', ID: "MLLT"> -- MPEG frames between reference $xx xx -- Bytes between reference $xx xx xx -- Milliseconds between reference $xx xx xx -- Bits for bytes deviation $xx -- Bits for milliseconds dev. $xx -- Then for every reference the following data is included; -- Deviation in bytes %xxx.... -- Deviation in milliseconds %xxx.... ---- --} ---- {-- TODO: 4.7. Synchronised tempo codes -- For a more accurate description of the tempo of a musical piece, this -- frame might be used. After the header follows one byte describing -- which time stamp format should be used. Then follows one or more -- tempo codes. Each tempo code consists of one tempo part and one time -- part. The tempo is in BPM described with one or two bytes. If the -- first byte has the value $FF, one more byte follows, which is added -- to the first giving a range from 2 - 510 BPM, since $00 and $01 is -- reserved. $00 is used to describe a beat-free time period, which is -- not the same as a music-free time period. $01 is used to indicate one -- single beat-stroke followed by a beat-free period. -- The tempo descriptor is followed by a time stamp. Every time the -- tempo in the music changes, a tempo descriptor may indicate this for -- the player. All tempo descriptors MUST be sorted in chronological -- order. The first beat-stroke in a time-period is at the same time as -- the beat description occurs. There may only be one "SYTC" frame in -- each tag. -- <Header for 'Synchronised tempo codes', ID: "SYTC"> -- Time stamp format $xx -- Tempo data <binary data> -- Where time stamp format is: -- $01 Absolute time, 32 bit sized, using MPEG [MPEG] frames as unit -- $02 Absolute time, 32 bit sized, using milliseconds as unit -- Absolute time means that every stamp contains the time from the -- beginning of the file. ---- --}} ---- {-- 4.8. Unsynchronised lyrics/text transcription -- This frame contains the lyrics of the song or a text transcription of -- other vocal activities. The head includes an encoding descriptor and -- a content descriptor. The body consists of the actual text. The -- 'Content descriptor' is a terminated string. If no descriptor is -- entered, 'Content descriptor' is $00 (00) only. Newline characters -- are allowed in the text. There may be more than one 'Unsynchronised -- lyrics/text transcription' frame in each tag, but only one with the -- same language and content descriptor. -- <Header for 'Unsynchronised lyrics/text transcription', ID: "USLT"> -- Text encoding $xx -- Language $xx xx xx -- Content descriptor <text string according to encoding> $00 (00) -- Lyrics/text <full text string according to encoding> frameInfo "USLT" = do enc0 <- parseEncoding lang0 <- parseLanguage descr0 <- parseString enc0 text0 <- parseString enc0 return $ USLT enc0 lang0 descr0 text0 ---- --} ---- {-- TODO: 4.9. Synchronised lyrics/text -- This is another way of incorporating the words, said or sung lyrics, -- in the audio file as text, this time, however, in sync with the -- audio. It might also be used to describing events e.g. occurring on a -- stage or on the screen in sync with the audio. The header includes a -- content descriptor, represented with as terminated text string. If no -- descriptor is entered, 'Content descriptor' is $00 (00) only. -- <Header for 'Synchronised lyrics/text', ID: "SYLT"> -- Text encoding $xx -- Language $xx xx xx -- Time stamp format $xx -- Content type $xx -- Content descriptor <text string according to encoding> $00 (00) -- Content type: $00 is other -- $01 is lyrics -- $02 is text transcription -- $03 is movement/part name (e.g. "Adagio") -- $04 is events (e.g. "Don Quijote enters the stage") -- $05 is chord (e.g. "Bb F Fsus") -- $06 is trivia/'pop up' information -- $07 is URLs to webpages -- $08 is URLs to images -- Time stamp format: -- $01 Absolute time, 32 bit sized, using MPEG [MPEG] frames as unit -- $02 Absolute time, 32 bit sized, using milliseconds as unit -- Absolute time means that every stamp contains the time from the -- beginning of the file. -- The text that follows the frame header differs from that of the -- unsynchronised lyrics/text transcription in one major way. Each -- syllable (or whatever size of text is considered to be convenient by -- the encoder) is a null terminated string followed by a time stamp -- denoting where in the sound file it belongs. Each sync thus has the -- following structure: -- Terminated text to be synced (typically a syllable) -- Sync identifier (terminator to above string) $00 (00) -- Time stamp $xx (xx ...) -- The 'time stamp' is set to zero or the whole sync is omitted if -- located directly at the beginning of the sound. All time stamps -- should be sorted in chronological order. The sync can be considered -- as a validator of the subsequent string. -- Newline characters are allowed in all "SYLT" frames and MUST be used -- after every entry (name, event etc.) in a frame with the content type -- $03 - $04. -- A few considerations regarding whitespace characters: Whitespace -- separating words should mark the beginning of a new word, thus -- occurring in front of the first syllable of a new word. This is also -- valid for new line characters. A syllable followed by a comma should -- not be broken apart with a sync (both the syllable and the comma -- should be before the sync). -- An example: The "USLT" passage -- "Strangers in the night" $0A "Exchanging glances" -- would be "SYLT" encoded as: -- "Strang" $00 xx xx "ers" $00 xx xx " in" $00 xx xx " the" $00 xx xx -- " night" $00 xx xx 0A "Ex" $00 xx xx "chang" $00 xx xx "ing" $00 xx -- xx "glan" $00 xx xx "ces" $00 xx xx -- There may be more than one "SYLT" frame in each tag, but only one -- with the same language and content descriptor. ---- --} ---- {-- 4.10. Comments -- This frame is intended for any kind of full text information that -- does not fit in any other frame. It consists of a frame header -- followed by encoding, language and content descriptors and is ended -- with the actual comment as a text string. Newline characters are -- allowed in the comment text string. There may be more than one -- comment frame in each tag, but only one with the same language and -- content descriptor. -- <Header for 'Comment', ID: "COMM"> -- Text encoding $xx -- Language $xx xx xx -- Short content descrip. <text string according to encoding> $00 (00) -- The actual text <full text string according to encoding> frameInfo "COMM" = do enc0 <- parseEncoding lang0 <- parseLanguage descr0 <- parseString enc0 text0 <- parseString enc0 --many' terminator -- ???!!!! return $ COMM enc0 lang0 descr0 text0 ---- --} ---- {-- TODO: 4.11. Relative volume adjustment (2) -- This is a more subjective frame than the previous ones. It allows the -- user to say how much he wants to increase/decrease the volume on each -- channel when the file is played. The purpose is to be able to align -- all files to a reference volume, so that you don't have to change the -- volume constantly. This frame may also be used to balance adjust the -- audio. The volume adjustment is encoded as a fixed point decibel -- value, 16 bit signed integer representing (adjustment*512), giving -- +/- 64 dB with a precision of 0.001953125 dB. E.g. +2 dB is stored as -- $04 00 and -2 dB is $FC 00. There may be more than one "RVA2" frame -- in each tag, but only one with the same identification string. -- <Header for 'Relative volume adjustment (2)', ID: "RVA2"> -- Identification <text string> $00 -- The 'identification' string is used to identify the situation and/or -- device where this adjustment should apply. The following is then -- repeated for every channel -- Type of channel $xx -- Volume adjustment $xx xx -- Bits representing peak $xx -- Peak volume $xx (xx ...) -- Type of channel: $00 Other -- $01 Master volume -- $02 Front right -- $03 Front left -- $04 Back right -- $05 Back left -- $06 Front centre -- $07 Back centre -- $08 Subwoofer -- Bits representing peak can be any number between 0 and 255. 0 means -- that there is no peak volume field. The peak volume field is always -- padded to whole bytes, setting the most significant bits to zero. ---- --} ---- {-- TODO: 4.12. Equalisation (2) -- This is another subjective, alignment frame. It allows the user to -- predefine an equalisation curve within the audio file. There may be -- more than one "EQU2" frame in each tag, but only one with the same -- identification string. -- <Header of 'Equalisation (2)', ID: "EQU2"> -- Interpolation method $xx -- Identification <text string> $00 -- The 'interpolation method' describes which method is preferred when -- an interpolation between the adjustment point that follows. The -- following methods are currently defined: -- $00 Band -- No interpolation is made. A jump from one adjustment level to -- another occurs in the middle between two adjustment points. -- $01 Linear -- Interpolation between adjustment points is linear. -- The 'identification' string is used to identify the situation and/or -- device where this adjustment should apply. The following is then -- repeated for every adjustment point -- Frequency $xx xx -- Volume adjustment $xx xx -- The frequency is stored in units of 1/2 Hz, giving it a range from 0 -- to 32767 Hz. -- The volume adjustment is encoded as a fixed point decibel value, 16 -- bit signed integer representing (adjustment*512), giving +/- 64 dB -- with a precision of 0.001953125 dB. E.g. +2 dB is stored as $04 00 -- and -2 dB is $FC 00. -- Adjustment points should be ordered by frequency and one frequency -- should only be described once in the frame. ---- --} ---- {-- TODO: 4.13. Reverb -- Yet another subjective frame, with which you can adjust echoes of -- different kinds. Reverb left/right is the delay between every bounce -- in ms. Reverb bounces left/right is the number of bounces that should -- be made. $FF equals an infinite number of bounces. Feedback is the -- amount of volume that should be returned to the next echo bounce. $00 -- is 0%, $FF is 100%. If this value were $7F, there would be 50% volume -- reduction on the first bounce, 50% of that on the second and so on. -- Left to left means the sound from the left bounce to be played in the -- left speaker, while left to right means sound from the left bounce to -- be played in the right speaker. -- 'Premix left to right' is the amount of left sound to be mixed in the -- right before any reverb is applied, where $00 id 0% and $FF is 100%. -- 'Premix right to left' does the same thing, but right to left. -- Setting both premix to $FF would result in a mono output (if the -- reverb is applied symmetric). There may only be one "RVRB" frame in -- each tag. -- <Header for 'Reverb', ID: "RVRB"> -- Reverb left (ms) $xx xx -- Reverb right (ms) $xx xx -- Reverb bounces, left $xx -- Reverb bounces, right $xx -- Reverb feedback, left to left $xx -- Reverb feedback, left to right $xx -- Reverb feedback, right to right $xx -- Reverb feedback, right to left $xx -- Premix left to right $xx -- Premix right to left $xx ---- --} ---- {-- 4.14. Attached picture -- This frame contains a picture directly related to the audio file. -- Image format is the MIME type and subtype [MIME] for the image. In -- the event that the MIME media type name is omitted, "image/" will be -- implied. The "image/png" [PNG] or "image/jpeg" [JFIF] picture format -- should be used when interoperability is wanted. Description is a -- short description of the picture, represented as a terminated -- text string. There may be several pictures attached to one file, each -- in their individual "APIC" frame, but only one with the same content -- descriptor. There may only be one picture with the picture type -- declared as picture type $01 and $02 respectively. There is the -- possibility to put only a link to the image file by using the 'MIME -- type' "-- >" and having a complete URL [URL] instead of picture data. -- The use of linked files should however be used sparingly since there -- is the risk of separation of files. -- <Header for 'Attached picture', ID: "APIC"> -- Text encoding $xx -- MIME type <text string> $00 -- Picture type $xx -- Description <text string according to encoding> $00 (00) -- Picture data <binary data> frameInfo "APIC" = do enc0 <- parseEncoding mime0 <- parseString 0 -- mimetype always encoded in ISO-8859-1 picType0 <- anyWord8 descr0 <- parseString enc0 picData0 <- many' anyWord8 return $ APIC enc0 mime0 picType0 descr0 picData0 -- Picture type: $00 Other -- $01 32x32 pixels 'file icon' (PNG only) -- $02 Other file icon -- $03 Cover (front) -- $04 Cover (back) -- $05 Leaflet page -- $06 Media (e.g. label side of CD) -- $07 Lead artist/lead performer/soloist -- $08 Artist/performer -- $09 Conductor -- $0A Band/Orchestra -- $0B Composer -- $0C Lyricist/text writer -- $0D Recording Location -- $0E During recording -- $0F During performance -- $10 Movie/video screen capture -- $11 A bright coloured fish -- $12 Illustration -- $13 Band/artist logotype -- $14 Publisher/Studio logotype ---- --} ---- {-- TODO: 4.15. General encapsulated object -- In this frame any type of file can be encapsulated. After the header, -- 'Frame size' and 'Encoding' follows 'MIME type' [MIME] represented as -- as a terminated string encoded with ISO 8859-1 [ISO-8859-1]. The -- filename is case sensitive and is encoded as 'Encoding'. Then follows -- a content description as terminated string, encoded as 'Encoding'. -- The last thing in the frame is the actual object. The first two -- strings may be omitted, leaving only their terminations. MIME type is -- always an ISO-8859-1 text string. There may be more than one "GEOB" -- frame in each tag, but only one with the same content descriptor. -- <Header for 'General encapsulated object', ID: "GEOB"> -- Text encoding $xx -- MIME type <text string> $00 -- Filename <text string according to encoding> $00 (00) -- Content description <text string according to encoding> $00 (00) -- Encapsulated object <binary data> ---- --} ---- {-- 4.16. Play counter -- This is simply a counter of the number of times a file has been -- played. The value is increased by one every time the file begins to -- play. There may only be one "PCNT" frame in each tag. When the -- counter reaches all one's, one byte is inserted in front of the -- counter thus making the counter eight bits bigger. The counter must -- be at least 32-bits long to begin with. -- <Header for 'Play counter', ID: "PCNT"> -- Counter $xx xx xx xx (xx ...) frameInfo "PCNT" = do cnt <- many' anyWord8 return $ PCNT (wordsToInteger cnt)-- ("Play counter", [("Counter", pack counter)]) ---- --} ---- {-- 4.17. Popularimeter -- The purpose of this frame is to specify how good an audio file is. -- Many interesting applications could be found to this frame such as a -- playlist that features better audio files more often than others or -- it could be used to profile a person's taste and find other 'good' -- files by comparing people's profiles. The frame contains the email -- address to the user, one rating byte and a four byte play counter, -- intended to be increased with one for every time the file is played. -- The email is a terminated string. The rating is 1-255 where 1 is -- worst and 255 is best. 0 is unknown. If no personal counter is wanted -- it may be omitted. When the counter reaches all one's, one byte is -- inserted in front of the counter thus making the counter eight bits -- bigger in the same away as the play counter ("PCNT"). There may be -- more than one "POPM" frame in each tag, but only one with the same -- email address. -- <Header for 'Popularimeter', ID: "POPM"> -- Email to user <text string> $00 -- Rating $xx -- Counter $xx xx xx xx (xx ...) frameInfo "POPM" = do --encSet 0x00 mail <- parseString 0 rate <- anyWord8 cnt <- many' anyWord8 return $ POPM mail (toInteger rate) (wordsToInteger cnt) ---- --} ---- {-- TODO: 4.18. Recommended buffer size -- Sometimes the server from which an audio file is streamed is aware of -- transmission or coding problems resulting in interruptions in the -- audio stream. In these cases, the size of the buffer can be -- recommended by the server using this frame. If the 'embedded info -- flag' is true (1) then this indicates that an ID3 tag with the -- maximum size described in 'Buffer size' may occur in the audio -- stream. In such case the tag should reside between two MPEG [MPEG] -- frames, if the audio is MPEG encoded. If the position of the next tag -- is known, 'offset to next tag' may be used. The offset is calculated -- from the end of tag in which this frame resides to the first byte of -- the header in the next. This field may be omitted. Embedded tags are -- generally not recommended since this could render unpredictable -- behaviour from present software/hardware. -- For applications like streaming audio it might be an idea to embed -- tags into the audio stream though. If the clients connects to -- individual connections like HTTP and there is a possibility to begin -- every transmission with a tag, then this tag should include a -- 'recommended buffer size' frame. If the client is connected to a -- arbitrary point in the stream, such as radio or multicast, then the -- 'recommended buffer size' frame SHOULD be included in every tag. -- The 'Buffer size' should be kept to a minimum. There may only be one -- "RBUF" frame in each tag. -- <Header for 'Recommended buffer size', ID: "RBUF"> -- Buffer size $xx xx xx -- Embedded info flag %0000000x -- Offset to next tag $xx xx xx xx ---- --} ---- {-- TODO: 4.19. Audio encryption -- This frame indicates if the actual audio stream is encrypted, and by -- whom. Since standardisation of such encryption scheme is beyond this -- document, all "AENC" frames begin with a terminated string with a -- URL containing an email address, or a link to a location where an -- email address can be found, that belongs to the organisation -- responsible for this specific encrypted audio file. Questions -- regarding the encrypted audio should be sent to the email address -- specified. If a $00 is found directly after the 'Frame size' and the -- audio file indeed is encrypted, the whole file may be considered -- useless. -- After the 'Owner identifier', a pointer to an unencrypted part of the -- audio can be specified. The 'Preview start' and 'Preview length' is -- described in frames. If no part is unencrypted, these fields should -- be left zeroed. After the 'preview length' field follows optionally a -- data block required for decryption of the audio. There may be more -- than one "AENC" frames in a tag, but only one with the same 'Owner -- identifier'. -- <Header for 'Audio encryption', ID: "AENC"> -- Owner identifier <text string> $00 -- Preview start $xx xx -- Preview length $xx xx -- Encryption info <binary data> ---- --} ---- {-- TODO: 4.20. Linked information -- To keep information duplication as low as possible this frame may be -- used to link information from another ID3v2 tag that might reside in -- another audio file or alone in a binary file. It is RECOMMENDED that -- this method is only used when the files are stored on a CD-ROM or -- other circumstances when the risk of file separation is low. The -- frame contains a frame identifier, which is the frame that should be -- linked into this tag, a URL [URL] field, where a reference to the -- file where the frame is given, and additional ID data, if needed. -- Data should be retrieved from the first tag found in the file to -- which this link points. There may be more than one "LINK" frame in a -- tag, but only one with the same contents. A linked frame is to be -- considered as part of the tag and has the same restrictions as if it -- was a physical part of the tag (i.e. only one "RVRB" frame allowed, -- whether it's linked or not). -- <Header for 'Linked information', ID: "LINK"> -- Frame identifier $xx xx xx xx -- URL <text string> $00 -- ID and additional data <text string(s)> -- Frames that may be linked and need no additional data are "ASPI", -- "ETCO", "EQU2", "MCID", "MLLT", "OWNE", "RVA2", "RVRB", "SYTC", the -- text information frames and the URL link frames. -- The "AENC", "APIC", "GEOB" and "TXXX" frames may be linked with -- the content descriptor as additional ID data. -- The "USER" frame may be linked with the language field as additional -- ID data. -- The "PRIV" frame may be linked with the owner identifier as -- additional ID data. -- The "COMM", "SYLT" and "USLT" frames may be linked with three bytes -- of language descriptor directly followed by a content descriptor as -- additional ID data. ---- --} ---- {-- TODO: 4.21. Position synchronisation frame -- This frame delivers information to the listener of how far into the -- audio stream he picked up; in effect, it states the time offset from -- the first frame in the stream. The frame layout is: -- <Head for 'Position synchronisation', ID: "POSS"> -- Time stamp format $xx -- Position $xx (xx ...) -- Where time stamp format is: -- $01 Absolute time, 32 bit sized, using MPEG frames as unit -- $02 Absolute time, 32 bit sized, using milliseconds as unit -- and position is where in the audio the listener starts to receive, -- i.e. the beginning of the next frame. If this frame is used in the -- beginning of a file the value is always 0. There may only be one -- "POSS" frame in each tag. ---- --} ---- {-- TODO: 4.22. Terms of use frame -- This frame contains a brief description of the terms of use and -- ownership of the file. More detailed information concerning the legal -- terms might be available through the "WCOP" frame. Newlines are -- allowed in the text. There may be more than one 'Terms of use' frame -- in a tag, but only one with the same 'Language'. -- <Header for 'Terms of use frame', ID: "USER"> -- Text encoding $xx -- Language $xx xx xx -- The actual text <text string according to encoding> ---- --} ---- {-- TODO: 4.23. Ownership frame -- The ownership frame might be used as a reminder of a made transaction -- or, if signed, as proof. Note that the "USER" and "TOWN" frames are -- good to use in conjunction with this one. The frame begins, after the -- frame ID, size and encoding fields, with a 'price paid' field. The -- first three characters of this field contains the currency used for -- the transaction, encoded according to ISO 4217 [ISO-4217] alphabetic -- currency code. Concatenated to this is the actual price paid, as a -- numerical string using "." as the decimal separator. Next is an 8 -- character date string (YYYYMMDD) followed by a string with the name -- of the seller as the last field in the frame. There may only be one -- "OWNE" frame in a tag. -- <Header for 'Ownership frame', ID: "OWNE"> -- Text encoding $xx -- Price paid <text string> $00 -- Date of purch. <text string> -- Seller <text string according to encoding> ---- --} ---- {-- TODO: 4.24. Commercial frame -- This frame enables several competing offers in the same tag by -- bundling all needed information. That makes this frame rather complex -- but it's an easier solution than if one tries to achieve the same -- result with several frames. The frame begins, after the frame ID, -- size and encoding fields, with a price string field. A price is -- constructed by one three character currency code, encoded according -- to ISO 4217 [ISO-4217] alphabetic currency code, followed by a -- numerical value where "." is used as decimal separator. In the price -- string several prices may be concatenated, separated by a "/" -- character, but there may only be one currency of each type. -- The price string is followed by an 8 character date string in the -- format YYYYMMDD, describing for how long the price is valid. After -- that is a contact URL, with which the user can contact the seller, -- followed by a one byte 'received as' field. It describes how the -- audio is delivered when bought according to the following list: -- $00 Other -- $01 Standard CD album with other songs -- $02 Compressed audio on CD -- $03 File over the Internet -- $04 Stream over the Internet -- $05 As note sheets -- $06 As note sheets in a book with other sheets -- $07 Music on other media -- $08 Non-musical merchandise -- Next follows a terminated string with the name of the seller followed -- by a terminated string with a short description of the product. The -- last thing is the ability to include a company logotype. The first of -- them is the 'Picture MIME type' field containing information about -- which picture format is used. In the event that the MIME media type -- name is omitted, "image/" will be implied. Currently only "image/png" -- and "image/jpeg" are allowed. This format string is followed by the -- binary picture data. This two last fields may be omitted if no -- picture is attached. There may be more than one 'commercial frame' in -- a tag, but no two may be identical. -- <Header for 'Commercial frame', ID: "COMR"> -- Text encoding $xx -- Price string <text string> $00 -- Valid until <text string> -- Contact URL <text string> $00 -- Received as $xx -- Name of seller <text string according to encoding> $00 (00) -- Description <text string according to encoding> $00 (00) -- Picture MIME type <string> $00 -- Seller logo <binary data> ---- --} ---- {-- TODO: 4.25. Encryption method registration -- To identify with which method a frame has been encrypted the -- encryption method must be registered in the tag with this frame. The -- 'Owner identifier' is a null-terminated string with a URL [URL] -- containing an email address, or a link to a location where an email -- address can be found, that belongs to the organisation responsible -- for this specific encryption method. Questions regarding the -- encryption method should be sent to the indicated email address. The -- 'Method symbol' contains a value that is associated with this method -- throughout the whole tag, in the range $80-F0. All other values are -- reserved. The 'Method symbol' may optionally be followed by -- encryption specific data. There may be several "ENCR" frames in a tag -- but only one containing the same symbol and only one containing the -- same owner identifier. The method must be used somewhere in the tag. -- See the description of the frame encryption flag in the ID3v2 -- structure document [ID3v2-strct] for more information. -- <Header for 'Encryption method registration', ID: "ENCR"> -- Owner identifier <text string> $00 -- Method symbol $xx -- Encryption data <binary data> ---- --} ---- {-- TODO: 4.26. Group identification registration -- This frame enables grouping of otherwise unrelated frames. This can -- be used when some frames are to be signed. To identify which frames -- belongs to a set of frames a group identifier must be registered in -- the tag with this frame. The 'Owner identifier' is a null-terminated -- string with a URL [URL] containing an email address, or a link to a -- location where an email address can be found, that belongs to the -- organisation responsible for this grouping. Questions regarding the -- grouping should be sent to the indicated email address. The 'Group -- symbol' contains a value that associates the frame with this group -- throughout the whole tag, in the range $80-F0. All other values are -- reserved. The 'Group symbol' may optionally be followed by some group -- specific data, e.g. a digital signature. There may be several "GRID" -- frames in a tag but only one containing the same symbol and only one -- containing the same owner identifier. The group symbol must be used -- somewhere in the tag. See the description of the frame grouping flag -- in the ID3v2 structure document [ID3v2-strct] for more information. -- <Header for 'Group ID registration', ID: "GRID"> -- Owner identifier <text string> $00 -- Group symbol $xx -- Group dependent data <binary data> ---- --} ---- {-- 4.27. Private frame -- This frame is used to contain information from a software producer -- that its program uses and does not fit into the other frames. The -- frame consists of an 'Owner identifier' string and the binary data. -- The 'Owner identifier' is a null-terminated string with a URL [URL] -- containing an email address, or a link to a location where an email -- address can be found, that belongs to the organisation responsible -- for the frame. Questions regarding the frame should be sent to the -- indicated email address. The tag may contain more than one "PRIV" -- frame but only with different contents. -- <Header for 'Private frame', ID: "PRIV"> -- Owner identifier <text string> $00 -- The private data <binary data> frameInfo "PRIV" = do ownerId0 <- parseString 0 privateData0 <- many' anyWord8 return $ PRIV ownerId0 privateData0 ---- --} ---- {-- TODO: 4.28. Signature frame -- This frame enables a group of frames, grouped with the 'Group -- identification registration', to be signed. Although signatures can -- reside inside the registration frame, it might be desired to store -- the signature elsewhere, e.g. in watermarks. There may be more than -- one 'signature frame' in a tag, but no two may be identical. -- <Header for 'Signature frame', ID: "SIGN"> -- Group symbol $xx -- Signature <binary data> ---- --} ---- {-- TODO: 4.29. Seek frame -- This frame indicates where other tags in a file/stream can be found. -- The 'minimum offset to next tag' is calculated from the end of this -- tag to the beginning of the next. There may only be one 'seek frame' -- in a tag. -- <Header for 'Seek frame', ID: "SEEK"> -- Minimum offset to next tag $xx xx xx xx ---- --} ---- {-- TODO: 4.30. Audio seek point index -- Audio files with variable bit rates are intrinsically difficult to -- deal with in the case of seeking within the file. The ASPI frame -- makes seeking easier by providing a list a seek points within the -- audio file. The seek points are a fractional offset within the audio -- data, providing a starting point from which to find an appropriate -- point to start decoding. The presence of an ASPI frame requires the -- existence of a TLEN frame, indicating the duration of the file in -- milliseconds. There may only be one 'audio seek point index' frame in -- a tag. -- <Header for 'Seek Point Index', ID: "ASPI"> -- Indexed data start (S) $xx xx xx xx -- Indexed data length (L) $xx xx xx xx -- Number of index points (N) $xx xx -- Bits per index point (b) $xx -- Then for every index point the following data is included; -- Fraction at index (Fi) $xx (xx) -- 'Indexed data start' is a byte offset from the beginning of the file. -- 'Indexed data length' is the byte length of the audio data being -- indexed. 'Number of index points' is the number of index points, as -- the name implies. The recommended number is 100. 'Bits per index -- point' is 8 or 16, depending on the chosen precision. 8 bits works -- well for short files (less than 5 minutes of audio), while 16 bits is -- advantageous for long files. 'Fraction at index' is the numerator of -- the fraction representing a relative position in the data. The -- denominator is 2 to the power of b. -- Here are the algorithms to be used in the calculation. The known data -- must be the offset of the start of the indexed data (S), the offset -- of the end of the indexed data (E), the number of index points (N), -- the offset at index i (Oi). We calculate the fraction at index i -- (Fi). -- Oi is the offset of the frame whose start is soonest after the point -- for which the time offset is (i/N * duration). -- The frame data should be calculated as follows: -- Fi = Oi/L * 2^b (rounded down to the nearest integer) -- Offset calculation should be calculated as follows from data in the -- frame: -- Oi = (Fi/2^b)*L (rounded up to the nearest integer) ---- --} {------------------------------------------------------------------------ - Legacy ID3v2.3 Frames - The following frames are not officially supported in ID3v2.4, but we - will at least support reading it in, both because we want to support - reading of ID3v2.3 tags and because some MP3/ID3 encoders seem to - illegally include the frames in ID3v2.4 tags. ------------------------------------------------------------------------} -- TYER -- The 'Year' frame is a numeric string with a year of the recording. -- frameInfo "TYER" = textInfo "Year" -- TYER -- The 'Date' frame is a numeric string in the DDMM format containing -- the date for the recording. -- This frame, like 'TYER', is also not formally supported in ID3v2.4. frameInfo "TDAT" = textInfo "Date" -- TSIZ -- The 'Size' frame contains the size of the audiofile in bytes, -- excluding the ID3v2 tag, represented as a numeric string. frameInfo "TSIZ" = textInfo "Size of file (in bytes) excluding ID3v2 tag" {------------------------------------------------------------------------} -- XXX: This default implementation of frameInfo does not work correctly -- for some reason... All frames coming after the unidentified frame -- will fail to be read. frameInfo _ = do frameData0 <- many' anyWord8 return $ Unknown frameData0