mirror of
https://github.com/wader/fq.git
synced 2024-12-26 15:02:28 +03:00
617 lines
20 KiB
Go
617 lines
20 KiB
Go
package id3
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// https://id3.org/id3v2.3.0
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// https://id3.org/id3v2.4.0-structure
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// https://id3.org/id3v2.4.0-frames
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// https://id3.org/id3v2-chapters-1.0
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import (
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"io"
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"strings"
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"github.com/wader/fq/format"
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"github.com/wader/fq/format/registry"
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"github.com/wader/fq/pkg/bitio"
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"github.com/wader/fq/pkg/decode"
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"github.com/wader/fq/pkg/scalar"
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"golang.org/x/text/encoding"
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"golang.org/x/text/encoding/charmap"
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"golang.org/x/text/encoding/unicode"
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)
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var imageFormat decode.Group
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func init() {
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registry.MustRegister(decode.Format{
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Name: format.ID3V2,
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Description: "ID3v2 metadata",
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DecodeFn: id3v2Decode,
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Dependencies: []decode.Dependency{
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{Names: []string{format.IMAGE}, Group: &imageFormat},
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},
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})
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}
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var idDescriptions = scalar.StrToScalar{
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"BUF": {Description: "Recommended buffer size"},
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"CNT": {Description: "Play counter"},
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"COM": {Description: "Comments"},
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"CRA": {Description: "Audio encryption"},
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"CRM": {Description: "Encrypted meta frame"},
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"EQU": {Description: "Equalization"},
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"ETC": {Description: "Event timing codes"},
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"GEO": {Description: "General encapsulated object"},
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"IPL": {Description: "Involved people list"},
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"LNK": {Description: "Linked information"},
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"MCI": {Description: "Music CD Identifier"},
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"MLL": {Description: "MPEG location lookup table"},
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"PIC": {Description: "Attached picture"},
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"POP": {Description: "Popularimeter"},
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"REV": {Description: "Reverb"},
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"RVA": {Description: "Relative volume adjustment"},
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"SLT": {Description: "Synchronized lyric/text"},
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"STC": {Description: "Synced tempo codes"},
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"TAL": {Description: "Album/Movie/Show title"},
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"TBP": {Description: "BPM (Beats Per Minute)"},
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"TCM": {Description: "Composer"},
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"TCO": {Description: "Content type"},
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"TCR": {Description: "Copyright message"},
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"TDA": {Description: "Date"},
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"TDY": {Description: "Playlist delay"},
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"TEN": {Description: "Encoded by"},
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"TFT": {Description: "File type"},
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"TIM": {Description: "Time"},
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"TKE": {Description: "Initial key"},
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"TLA": {Description: "Language(s)"},
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"TLE": {Description: "Length"},
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"TMT": {Description: "Media type"},
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"TOA": {Description: "Original artist(s)/performer(s)"},
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"TOF": {Description: "Original filename"},
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"TOL": {Description: "Original Lyricist(s)/text writer(s)"},
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"TOR": {Description: "Original release year"},
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"TOT": {Description: "Original album/Movie/Show title"},
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"TP1": {Description: "Lead artist(s)/Lead performer(s)/Soloist(s)/Performing group"},
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"TP2": {Description: "Band/Orchestra/Accompaniment"},
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"TP3": {Description: "Conductor/Performer refinement"},
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"TP4": {Description: "Interpreted, remixed, or otherwise modified by"},
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"TPA": {Description: "Part of a set"},
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"TPB": {Description: "Publisher"},
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"TRC": {Description: "ISRC (International Standard Recording Code)"},
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"TRD": {Description: "Recording dates"},
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"TRK": {Description: "Track number/Position in set"},
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"TSI": {Description: "Size"},
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"TSS": {Description: "Software/hardware and settings used for encoding"},
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"TT1": {Description: "Content group description"},
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"TT2": {Description: "Title/Songname/Content description"},
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"TT3": {Description: "Subtitle/Description refinement"},
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"TXT": {Description: "Lyricist/text writer"},
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"TXX": {Description: "User defined text information frame"},
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"TYE": {Description: "Year"},
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"UFI": {Description: "Unique file identifier"},
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"ULT": {Description: "Unsychronized lyric/text transcription"},
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"WAF": {Description: "Official audio file webpage"},
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"WAR": {Description: "Official artist/performer webpage"},
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"WAS": {Description: "Official audio source webpage"},
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"WCM": {Description: "Commercial information"},
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"WCP": {Description: "Copyright/Legal information"},
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"WPB": {Description: "Publishers official webpage"},
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"WXX": {Description: "User defined URL link frame"},
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"AENC": {Description: "Audio encryption"},
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"APIC": {Description: "Attached picture"},
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"ASPI": {Description: "Audio seek point index"},
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"CHAP": {Description: "Chapter"},
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"COMM": {Description: "Comments"},
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"COMR": {Description: "Commercial frame"},
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"CTOC": {Description: "Table of contents"},
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"ENCR": {Description: "Encryption method registration"},
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"EQU2": {Description: "Equalisation (2)"},
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"EQUA": {Description: "Equalization"},
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"ETCO": {Description: "Event timing codes"},
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"GEOB": {Description: "General encapsulated object"},
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"GRID": {Description: "Group identification registration"},
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"IPLS": {Description: "Involved people list"},
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"LINK": {Description: "Linked information"},
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"MCDI": {Description: "Music CD identifier"},
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"MLLT": {Description: "MPEG location lookup table"},
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"OWNE": {Description: "Ownership frame"},
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"PCNT": {Description: "Play counter"},
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"POPM": {Description: "Popularimeter"},
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"POSS": {Description: "Position synchronisation frame"},
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"PRIV": {Description: "Private frame"},
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"RBUF": {Description: "Recommended buffer size"},
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"RVA2": {Description: "Relative volume adjustment (2)"},
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"RVAD": {Description: "Relative volume adjustment"},
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"RVRB": {Description: "Reverb"},
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"SEEK": {Description: "Seek frame"},
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"SIGN": {Description: "Signature frame"},
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"SYLT": {Description: "Synchronized lyric/text"},
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"SYTC": {Description: "Synchronized tempo codes"},
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"TALB": {Description: "Album/Movie/Show title"},
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"TBPM": {Description: "BPM (beats per minute)"},
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"TCOM": {Description: "Composer"},
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"TCON": {Description: "Content type"},
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"TCOP": {Description: "Copyright message"},
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"TDAT": {Description: "Date"},
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"TDEN": {Description: "Encoding time"},
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"TDLY": {Description: "Playlist delay"},
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"TDOR": {Description: "Original release time"},
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"TDRC": {Description: "Recording time"},
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"TDRL": {Description: "Release time"},
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"TDTG": {Description: "Tagging time"},
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"TENC": {Description: "Encoded by"},
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"TEXT": {Description: "Lyricist/Text writer"},
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"TFLT": {Description: "File type"},
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"TIME": {Description: "Time"},
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"TIPL": {Description: "Involved people list"},
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"TIT1": {Description: "Content group description"},
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"TIT2": {Description: "Title/songname/content description"},
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"TIT3": {Description: "Subtitle/Description refinement"},
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"TKEY": {Description: "Initial key"},
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"TLAN": {Description: "Language(s)"},
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"TLEN": {Description: "Length"},
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"TMCL": {Description: "Musician credits list"},
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"TMED": {Description: "Media type"},
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"TMOO": {Description: "Mood"},
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"TOAL": {Description: "Original album/movie/show title"},
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"TOFN": {Description: "Original filename"},
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"TOLY": {Description: "Original lyricist(s)/text writer(s)"},
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"TOPE": {Description: "Original artist(s)/performer(s)"},
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"TORY": {Description: "Original release year"},
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"TOWN": {Description: "File owner/licensee"},
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"TPE1": {Description: "Lead performer(s)/Soloist(s)"},
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"TPE2": {Description: "Band/orchestra/accompaniment"},
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"TPE3": {Description: "Conductor/performer refinement"},
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"TPE4": {Description: "Interpreted, remixed, or otherwise modified by"},
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"TPOS": {Description: "Part of a set"},
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"TPRO": {Description: "Produced notice"},
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"TPUB": {Description: "Publisher"},
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"TRCK": {Description: "Track number/Position in set"},
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"TRDA": {Description: "Recording dates"},
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"TRSN": {Description: "Internet radio station name"},
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"TRSO": {Description: "Internet radio station owner"},
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"TSIZ": {Description: "Size"},
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"TSOA": {Description: "Album sort order"},
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"TSOP": {Description: "Performer sort order"},
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"TSOT": {Description: "Title sort order"},
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"TSRC": {Description: "ISRC (international standard recording code)"},
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"TSSE": {Description: "Software/Hardware and settings used for encoding"},
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"TSST": {Description: "Set subtitle"},
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"TXXX": {Description: "User defined text information frame"},
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"TYER": {Description: "Year"},
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"UFID": {Description: "Unique file identifier"},
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"USER": {Description: "Terms of use"},
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"USLT": {Description: "Unsychronized lyric/text transcription"},
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"WCOM": {Description: "Commercial information"},
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"WCOP": {Description: "Copyright/Legal information"},
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"WOAF": {Description: "Official audio file webpage"},
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"WOAR": {Description: "Official artist/performer webpage"},
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"WOAS": {Description: "Official audio source webpage"},
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"WORS": {Description: "Official Internet radio station homepage"},
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"WPAY": {Description: "Payment"},
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"WPUB": {Description: "Publishers official webpage"},
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"WXXX": {Description: "User defined URL link frame"},
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}
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// id3v2 MPEG/AAC unsynchronisation reader
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// Replace 0xff 0x00 0xab with 0xff 0xab in byte stream
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type unsyncReader struct {
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io.Reader
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lastFF bool
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}
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func (r unsyncReader) Read(p []byte) (n int, err error) {
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n, err = r.Reader.Read(p)
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ni := 0
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for i, b := range p[0:n] {
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if r.lastFF && b == 0x00 {
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n--
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r.lastFF = false
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continue
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} else {
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r.lastFF = b == 0xff
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}
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p[ni] = p[i]
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ni++
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}
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return n, err
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}
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const (
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encodingISO8859_1 = 0
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encodingUTF16 = 1
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encodingUTF16BE = 2
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encodingUTF8 = 3
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)
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// $00 ISO-8859-1 [ISO-8859-1]. Terminated with $00.
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// $01 UTF-16 [UTF-16] encoded Unicode [UNICODE] with BOM. All
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// strings in the same frame SHALL have the same byteorder.
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// Terminated with $00 00.
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// $02 UTF-16BE [UTF-16] encoded Unicode [UNICODE] without BOM.
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// Terminated with $00 00.
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// $03 UTF-8 [UTF-8] encoded Unicode [UNICODE]. Terminated with $00.
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var encodingNames = scalar.UToSymStr{
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encodingISO8859_1: "ISO-8859-1",
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encodingUTF16: "UTF-16",
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encodingUTF16BE: "UTF-16BE",
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encodingUTF8: "UTF-8",
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}
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var encodingLen = map[uint64]int64{
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encodingISO8859_1: 1,
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encodingUTF16: 2,
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encodingUTF16BE: 2,
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encodingUTF8: 1,
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}
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func decodeToString(e int, b []byte) string {
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var enc encoding.Encoding
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switch e {
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case encodingISO8859_1:
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enc = charmap.ISO8859_1
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case encodingUTF16:
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enc = unicode.UTF16(unicode.LittleEndian, unicode.UseBOM)
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case encodingUTF16BE:
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enc = unicode.UTF16(unicode.BigEndian, unicode.IgnoreBOM)
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default:
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enc = unicode.UTF8
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}
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// TODO: try decode?
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s, _ := enc.NewDecoder().String(string(b))
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return s
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}
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func decodeSyncSafeU32(d *decode.D) uint64 {
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u := d.U32()
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// syncsafe integer is a number encoded
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// with 8th bit in each byte set to zero
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// 0aaaaaaa0bbbbbbb0ccccccc0ddddddd ->
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// 0000aaaaaaabbbbbbbcccccccddddddd
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return (((u & 0x7f000000) >> 3) |
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((u & 0x007f0000) >> 2) |
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((u & 0x00007f00) >> 1) |
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((u & 0x0000007f) >> 0))
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}
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func textFn(encoding int, nBytes int) func(d *decode.D) string {
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return func(d *decode.D) string {
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return strings.TrimRight(decodeToString(encoding, d.BytesLen(nBytes)), "\x00")
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}
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}
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func textNullFn(encoding int) func(d *decode.D) string {
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return func(d *decode.D) string {
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nullLen := encodingLen[encodingUTF8]
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if n, ok := encodingLen[uint64(encoding)]; ok {
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nullLen = n
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}
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offset, _ := d.PeekFind(
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int(nullLen)*8,
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nullLen*8,
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-1,
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func(v uint64) bool { return v == 0 },
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)
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offsetBytes := offset / 8
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text := textFn(encoding, int(offsetBytes))(d)
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d.SeekRel(nullLen * 8)
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// seems sometimes utf16 etc has en exta null byte
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if nullLen > 1 && d.PeekBits(8) == 0 {
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d.SeekRel(8)
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}
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return text
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}
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}
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func decodeFrame(d *decode.D, version int) uint64 {
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var id string
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var size uint64
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var dataSize uint64
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// TODO: global tag unsync?
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unsyncFlag := false
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switch version {
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case 2:
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// Frame ID "XXX"
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// Frame size $xx xx xx
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id = d.FieldUTF8("id", 3, idDescriptions)
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dataSize = d.FieldU24("size")
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size = dataSize + 6
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case 3:
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// Frame ID $xx xx xx xx (four characters)
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// Size $xx xx xx xx
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// Flags $xx xx
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id = d.FieldUTF8("id", 4, idDescriptions)
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dataSize = d.FieldU32("size")
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d.FieldStruct("flags", func(d *decode.D) {
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// %abc00000 %ijk00000
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d.FieldBool("tag_alter_preservation")
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d.FieldBool("file_alter_preservation")
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d.FieldBool("read_only")
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d.FieldU5("unused0")
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d.FieldBool("compression")
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// TODO: read encryption byte, skip decode of frame data?
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d.FieldBool("encryption")
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d.FieldBool("grouping_identity")
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d.FieldU5("unused1")
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})
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size = dataSize + 10
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case 4:
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// Frame ID $xx xx xx xx (four characters)
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// Size 4 * %0xxxxxxx (synchsafe integer)
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// Flags $xx xx
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id = d.FieldUTF8("id", 4, idDescriptions)
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dataSize = d.FieldUFn("size", decodeSyncSafeU32)
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var headerLen uint64 = 10
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dataLenFlag := false
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d.FieldStruct("flags", func(d *decode.D) {
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// %0abc0000 %0h00kmnp
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d.FieldU1("unused0")
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d.FieldBool("tag_alter_preservation")
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d.FieldBool("file_alter_preservation")
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d.FieldBool("read_only")
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d.FieldU5("unused1")
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d.FieldBool("grouping_identity")
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d.FieldU2("unused2")
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d.FieldBool("compression")
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// TODO: read encryption byte, skip decode of frame data?
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d.FieldBool("encryption")
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unsyncFlag = d.FieldBool("unsync")
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dataLenFlag = d.FieldBool("data_length_indicator")
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})
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if dataLenFlag {
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d.FieldUFn("data_length_indicator", decodeSyncSafeU32)
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dataSize -= 4
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headerLen += 4
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}
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size = dataSize + headerLen
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default:
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// can't know size
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d.Fatalf("unknown version")
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}
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// note frame function run inside a SubLenFn so they can use BitLefts and
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// can't accidentally read too far
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frames := map[string]func(d *decode.D){
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// <ID3v2.3 or ID3v2.4 frame header, ID: "CHAP"> (10 bytes)
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// Element ID <text string> $00
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// Start time $xx xx xx xx
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// End time $xx xx xx xx
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// Start offset $xx xx xx xx
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// End offset $xx xx xx xx
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// <Optional embedded sub-frames>
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"CHAP": func(d *decode.D) {
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d.FieldStrFn("element_id", textNullFn(encodingUTF8))
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d.FieldU32("start_time")
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d.FieldU32("end_time")
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d.FieldU32("start_offset")
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d.FieldU32("end_offset")
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decodeFrames(d, version, uint64(d.BitsLeft()/8))
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},
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"CTOC": func(d *decode.D) {
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d.FieldStrFn("element_id", textNullFn(encodingUTF8))
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d.FieldU8("ctoc_flags")
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entryCount := d.FieldU8("entry_count")
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d.FieldArray("entries", func(d *decode.D) {
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for i := uint64(0); i < entryCount; i++ {
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d.FieldStrFn("entry", textNullFn(encodingUTF8))
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}
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})
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},
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// <Header for 'Attached picture', ID: "APIC">
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// Text encoding $xx
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// MIME type <text string> $00
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// Picture type $xx
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// Description <text string according to encoding> $00 (00)
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// Picture data <binary data>
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"APIC": func(d *decode.D) {
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encoding := d.FieldU8("text_encoding", encodingNames)
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d.FieldStrFn("mime_type", textNullFn(encodingUTF8))
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d.FieldU8("picture_type") // TODO: table
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d.FieldStrFn("description", textNullFn(int(encoding)))
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dv, _, _ := d.TryFieldFormatLen("picture", d.BitsLeft(), imageFormat, nil)
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if dv == nil {
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d.FieldRawLen("picture", d.BitsLeft())
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}
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},
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// <Header for 'General encapsulated object', ID: "GEOB">
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// Text encoding $xx
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// MIME type <text string> $00
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// Filename <text string according to encoding> $00 (00)
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// Content description <text string according to encoding> $00 (00)
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// Encapsulated object <binary data>
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"GEOB": func(d *decode.D) {
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encoding := d.FieldU8("text_encoding", encodingNames)
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d.FieldStrFn("mime_type", textNullFn(encodingUTF8))
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d.FieldStrFn("filename", textNullFn(int(encoding)))
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d.FieldStrFn("description", textNullFn(int(encoding)))
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dv, _, _ := d.TryFieldFormatLen("data", d.BitsLeft(), imageFormat, nil)
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if dv == nil {
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d.FieldRawLen("data", d.BitsLeft())
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}
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},
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// Unsynced lyrics/text "ULT"
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// Frame size $xx xx xx
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// Text encoding $xx
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// Language $xx xx xx
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// Content descriptor <textstring> $00 (00)
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// Lyrics/text <textstring>
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//
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// <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>
|
|
//
|
|
// Comment "COM"
|
|
// Frame size $xx xx xx
|
|
// Text encoding $xx
|
|
// Language $xx xx xx
|
|
// Short content description <textstring> $00 (00)
|
|
// The actual text <textstring>
|
|
//
|
|
// <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>
|
|
"COMM": func(d *decode.D) {
|
|
encoding := d.FieldU8("text_encoding", encodingNames)
|
|
d.FieldUTF8("language", 3)
|
|
d.FieldStrFn("description", textNullFn(int(encoding)))
|
|
d.FieldStrFn("value", textFn(int(encoding), int(d.BitsLeft()/8)))
|
|
},
|
|
// Text information identifier "T00" - "TZZ" , excluding "TXX",
|
|
// described in 4.2.2.
|
|
// Frame size $xx xx xx
|
|
// Text encoding $xx
|
|
// Information <textstring>
|
|
//
|
|
// <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>
|
|
"T000": func(d *decode.D) {
|
|
encoding := d.FieldU8("text_encoding", encodingNames)
|
|
d.FieldStrFn("text", textFn(int(encoding), int(d.BitsLeft()/8)))
|
|
},
|
|
// User defined... "TXX"
|
|
// Frame size $xx xx xx
|
|
// Text encoding $xx
|
|
// Description <textstring> $00 (00)
|
|
// Value <textstring>
|
|
//
|
|
// <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>
|
|
"TXXX": func(d *decode.D) {
|
|
encoding := d.FieldU8("text_encoding", encodingNames)
|
|
d.FieldStrFn("description", textNullFn(int(encoding)))
|
|
d.FieldStrFn("value", textFn(int(encoding), int(d.BitsLeft()/8)))
|
|
},
|
|
// <Header for 'Private frame', ID: "PRIV">
|
|
// Owner identifier <text string> $00
|
|
// The private data <binary data>
|
|
"PRIV": func(d *decode.D) {
|
|
// TODO: is default ISO8859-1?
|
|
d.FieldStrFn("owner", textNullFn(int(encodingISO8859_1)))
|
|
d.FieldRawLen("data", d.BitsLeft())
|
|
},
|
|
}
|
|
|
|
idNormalized := id
|
|
switch {
|
|
case id == "COMM", id == "COM", id == "USLT", id == "ULT":
|
|
idNormalized = "COMM"
|
|
case id == "TXX", id == "TXXX":
|
|
idNormalized = "TXXX"
|
|
case len(id) > 0 && id[0] == 'T':
|
|
idNormalized = "T000"
|
|
}
|
|
|
|
if unsyncFlag {
|
|
// TODO: DecodeFn
|
|
// TODO: unknown after frame decode
|
|
unsyncedBR := d.MustNewBitBufFromReader(unsyncReader{Reader: bitio.NewIOReader(d.BitBufRange(d.Pos(), int64(dataSize)*8))})
|
|
d.FieldFormatBitBuf("unsync", unsyncedBR, decode.FormatFn(func(d *decode.D, in interface{}) interface{} {
|
|
if fn, ok := frames[idNormalized]; ok {
|
|
fn(d)
|
|
} else {
|
|
d.FieldRawLen("data", d.BitsLeft())
|
|
}
|
|
|
|
return nil
|
|
}), nil)
|
|
d.FieldRawLen("data", int64(dataSize*8))
|
|
} else {
|
|
if fn, ok := frames[idNormalized]; ok {
|
|
d.FramedFn(int64(dataSize)*8, func(d *decode.D) {
|
|
fn(d)
|
|
})
|
|
} else {
|
|
d.FieldRawLen("data", int64(dataSize*8))
|
|
}
|
|
}
|
|
|
|
return size
|
|
}
|
|
|
|
func decodeFrames(d *decode.D, version int, size uint64) {
|
|
d.FieldArray("frames", func(d *decode.D) {
|
|
for size > 0 {
|
|
if d.PeekBits(8) == 0 {
|
|
return
|
|
}
|
|
|
|
d.FieldStruct("frame", func(d *decode.D) {
|
|
size -= decodeFrame(d, version)
|
|
})
|
|
}
|
|
})
|
|
|
|
if size > 0 {
|
|
d.FieldRawLen("padding", int64(size*8), d.BitBufIsZero())
|
|
}
|
|
}
|
|
|
|
func id3v2Decode(d *decode.D, in interface{}) interface{} {
|
|
d.AssertAtLeastBitsLeft(4 * 8)
|
|
d.FieldUTF8("magic", 3, d.AssertStr("ID3"))
|
|
version := int(d.FieldU8("version"))
|
|
versionValid := version == 2 || version == 3 || version == 4
|
|
if !versionValid {
|
|
d.Fatalf("unsupported version %d", version)
|
|
}
|
|
|
|
d.FieldU8("revision")
|
|
var extendedHeader bool
|
|
d.FieldStruct("flags", func(d *decode.D) {
|
|
d.FieldBool("unsynchronisation")
|
|
extendedHeader = d.FieldBool("extended_header")
|
|
d.FieldBool("experimental_indicator")
|
|
d.FieldU5("unused")
|
|
})
|
|
size := d.FieldUFn("size", decodeSyncSafeU32)
|
|
|
|
var extHeaderSize uint64
|
|
if extendedHeader {
|
|
d.FieldStruct("extended_header", func(d *decode.D) {
|
|
switch version {
|
|
case 3:
|
|
extHeaderSize = d.FieldU32("size")
|
|
d.FieldRawLen("data", int64(extHeaderSize)*8)
|
|
case 4:
|
|
extHeaderSize = d.FieldUFn("size", decodeSyncSafeU32)
|
|
// in v4 synchsafe integer includes itself
|
|
d.FieldRawLen("data", (int64(extHeaderSize)-4)*8)
|
|
}
|
|
})
|
|
}
|
|
|
|
decodeFrames(d, version, size)
|
|
|
|
return nil
|
|
}
|