mirror of
https://github.com/wader/fq.git
synced 2024-11-23 18:56:52 +03:00
630 lines
18 KiB
Go
630 lines
18 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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"fmt"
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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/decode"
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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.Format
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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}, Formats: &imageFormat},
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},
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})
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}
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var idDescriptions = map[string]string{
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"CHAP": "Chapter",
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"CTOC": "Table of contents",
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"AENC": "Audio encryption",
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"APIC": "Attached picture",
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"ASPI": "Audio seek point index",
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"COMM": "Comments",
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"COMR": "Commercial frame",
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"ENCR": "Encryption method registration",
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"EQU2": "Equalisation (2)",
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"EQUA": "Equalization",
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"ETCO": "Event timing codes",
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"GEOB": "General encapsulated object",
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"GRID": "Group identification registration",
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"IPLS": "Involved people list",
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"LINK": "Linked information",
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"MCDI": "Music CD identifier",
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"MLLT": "MPEG location lookup table",
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"OWNE": "Ownership frame",
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"PCNT": "Play counter",
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"POPM": "Popularimeter",
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"POSS": "Position synchronisation frame",
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"PRIV": "Private frame",
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"RBUF": "Recommended buffer size",
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"RVA2": "Relative volume adjustment (2)",
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"RVAD": "Relative volume adjustment",
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"RVRB": "Reverb",
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"SEEK": "Seek frame",
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"SIGN": "Signature frame",
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"SYLT": "Synchronized lyric/text",
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"SYTC": "Synchronized tempo codes",
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"TALB": "Album/Movie/Show title",
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"TBPM": "BPM (beats per minute)",
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"TCOM": "Composer",
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"TCON": "Content type",
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"TCOP": "Copyright message",
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"TDAT": "Date",
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"TDEN": "Encoding time",
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"TDLY": "Playlist delay",
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"TDOR": "Original release time",
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"TDRC": "Recording time",
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"TDRL": "Release time",
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"TDTG": "Tagging time",
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"TENC": "Encoded by",
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"TEXT": "Lyricist/Text writer",
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"TFLT": "File type",
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"TIME": "Time",
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"TIPL": "Involved people list",
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"TIT1": "Content group description",
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"TIT2": "Title/songname/content description",
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"TIT3": "Subtitle/Description refinement",
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"TKEY": "Initial key",
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"TLAN": "Language(s)",
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"TLEN": "Length",
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"TMCL": "Musician credits list",
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"TMED": "Media type",
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"TMOO": "Mood",
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"TOAL": "Original album/movie/show title",
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"TOFN": "Original filename",
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"TOLY": "Original lyricist(s)/text writer(s)",
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"TOPE": "Original artist(s)/performer(s)",
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"TORY": "Original release year",
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"TOWN": "File owner/licensee",
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"TPE1": "Lead performer(s)/Soloist(s)",
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"TPE2": "Band/orchestra/accompaniment",
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"TPE3": "Conductor/performer refinement",
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"TPE4": "Interpreted, remixed, or otherwise modified by",
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"TPOS": "Part of a set",
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"TPRO": "Produced notice",
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"TPUB": "Publisher",
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"TRCK": "Track number/Position in set",
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"TRDA": "Recording dates",
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"TRSN": "Internet radio station name",
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"TRSO": "Internet radio station owner",
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"TSIZ": "Size",
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"TSOA": "Album sort order",
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"TSOP": "Performer sort order",
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"TSOT": "Title sort order",
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"TSRC": "ISRC (international standard recording code)",
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"TSSE": "Software/Hardware and settings used for encoding",
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"TSST": "Set subtitle",
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"TXXX": "User defined text information frame",
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"TYER": "Year",
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"UFID": "Unique file identifier",
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"USER": "Terms of use",
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"USLT": "Unsychronized lyric/text transcription",
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"WCOM": "Commercial information",
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"WCOP": "Copyright/Legal information",
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"WOAF": "Official audio file webpage",
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"WOAR": "Official artist/performer webpage",
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"WOAS": "Official audio source webpage",
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"WORS": "Official Internet radio station homepage",
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"WPAY": "Payment",
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"WPUB": "Publishers official webpage",
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"WXXX": "User defined URL link frame",
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"BUF": "Recommended buffer size",
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"CNT": "Play counter",
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"COM": "Comments",
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"CRA": "Audio encryption",
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"CRM": "Encrypted meta frame",
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"ETC": "Event timing codes",
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"EQU": "Equalization",
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"GEO": "General encapsulated object",
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"IPL": "Involved people list",
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"LNK": "Linked information",
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"MCI": "Music CD Identifier",
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"MLL": "MPEG location lookup table",
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"PIC": "Attached picture",
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"POP": "Popularimeter",
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"REV": "Reverb",
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"RVA": "Relative volume adjustment",
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"SLT": "Synchronized lyric/text",
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"STC": "Synced tempo codes",
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"TAL": "Album/Movie/Show title",
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"TBP": "BPM (Beats Per Minute)",
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"TCM": "Composer",
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"TCO": "Content type",
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"TCR": "Copyright message",
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"TDA": "Date",
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"TDY": "Playlist delay",
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"TEN": "Encoded by",
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"TFT": "File type",
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"TIM": "Time",
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"TKE": "Initial key",
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"TLA": "Language(s)",
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"TLE": "Length",
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"TMT": "Media type",
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"TOA": "Original artist(s)/performer(s)",
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"TOF": "Original filename",
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"TOL": "Original Lyricist(s)/text writer(s)",
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"TOR": "Original release year",
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"TOT": "Original album/Movie/Show title",
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"TP1": "Lead artist(s)/Lead performer(s)/Soloist(s)/Performing group",
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"TP2": "Band/Orchestra/Accompaniment",
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"TP3": "Conductor/Performer refinement",
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"TP4": "Interpreted, remixed, or otherwise modified by",
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"TPA": "Part of a set",
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"TPB": "Publisher",
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"TRC": "ISRC (International Standard Recording Code)",
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"TRD": "Recording dates",
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"TRK": "Track number/Position in set",
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"TSI": "Size",
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"TSS": "Software/hardware and settings used for encoding",
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"TT1": "Content group description",
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"TT2": "Title/Songname/Content description",
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"TT3": "Subtitle/Description refinement",
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"TXT": "Lyricist/text writer",
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"TXX": "User defined text information frame",
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"TYE": "Year",
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"UFI": "Unique file identifier",
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"ULT": "Unsychronized lyric/text transcription",
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"WAF": "Official audio file webpage",
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"WAR": "Official artist/performer webpage",
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"WAS": "Official audio source webpage",
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"WCM": "Commercial information",
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"WCP": "Copyright/Legal information",
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"WPB": "Publishers official webpage",
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"WXX": "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 = map[uint64]string{
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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 syncSafeU32(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 text(d *decode.D, encoding int, nBytes int) string {
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return strings.TrimRight(decodeToString(encoding, d.BytesLen(nBytes)), "\x00")
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}
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func textNull(d *decode.D, encoding int) 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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func(v uint64) bool { return v == 0 },
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-1,
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)
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offsetBytes := offset / 8
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text := text(d, encoding, int(offsetBytes))
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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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func fieldSyncSafeU32(d *decode.D, name string) uint64 {
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return d.FieldUFn(name, func() (uint64, decode.DisplayFormat, string) {
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return syncSafeU32(d), decode.NumberDecimal, ""
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})
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}
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func fieldTextNull(d *decode.D, name string, encoding int) string { //nolint:unparam
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return d.FieldStrFn(name, func() (string, string) {
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return textNull(d, encoding), ""
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})
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}
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func fieldText(d *decode.D, name string, encoding int, nBytes int) string { //nolint:unparam
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return d.FieldStrFn(name, func() (string, string) {
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return text(d, encoding, nBytes), ""
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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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switch version {
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case 2:
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id = d.UTF8(3)
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d.SeekRel(-3 * 8)
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case 3, 4:
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id = d.UTF8(4)
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d.SeekRel(-4 * 8)
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}
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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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idDescription := ""
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if d, ok := idDescriptions[id]; ok {
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idDescription = d
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}
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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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d.FieldStrFn("id", func() (string, string) { return d.UTF8(3), idDescription })
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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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d.FieldStrFn("id", func() (string, string) { return d.UTF8(4), idDescription })
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dataSize = d.FieldU32("size")
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d.FieldStructFn("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 encruption 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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d.FieldStrFn("id", func() (string, string) { return d.UTF8(4), idDescription })
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dataSize = fieldSyncSafeU32(d, "size")
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var headerLen uint64 = 10
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dataLenFlag := false
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d.FieldStructFn("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 encruption 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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fieldSyncSafeU32(d, "data_length_indicator")
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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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}
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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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fieldTextNull(d, "element_id", 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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fieldTextNull(d, "element_id", encodingUTF8)
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d.FieldU8("ctoc_flags")
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entryCount := d.FieldU8("entry_count")
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d.FieldArrayFn("entries", func(d *decode.D) {
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for i := uint64(0); i < entryCount; i++ {
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fieldTextNull(d, "entry", 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.FieldStringMapFn("text_encoding", encodingNames, "unknown", d.U8, decode.NumberDecimal)
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fieldTextNull(d, "mime_type", encodingUTF8)
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d.FieldU8("picture_type") // TODO: table
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fieldTextNull(d, "description", int(encoding))
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dv, _, _ := d.FieldTryFormatLen("picture", d.BitsLeft(), imageFormat)
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if dv == nil {
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d.FieldBitBufLen("picture", 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">
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// Text encoding $xx
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// Language $xx xx xx
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// Content descriptor <text string according to encoding> $00 (00)
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// Lyrics/text <full text string according to encoding>
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//
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// Comment "COM"
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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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// Short content description <textstring> $00 (00)
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// The actual text <textstring>
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//
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// <Header for 'Comment', ID: "COMM">
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// Text encoding $xx
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// Language $xx xx xx
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// Short content descrip. <text string according to encoding> $00 (00)
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// The actual text <full text string according to encoding>
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"COMM": func(d *decode.D) {
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encoding, _ := d.FieldStringMapFn("text_encoding", encodingNames, "unknown", d.U8, decode.NumberDecimal)
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d.FieldUTF8("language", 3)
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fieldTextNull(d, "description", int(encoding))
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fieldText(d, "value", int(encoding), int(d.BitsLeft()/8))
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|
},
|
|
// 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.FieldStringMapFn("text_encoding", encodingNames, "unknown", d.U8, decode.NumberDecimal)
|
|
fieldText(d, "text", 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.FieldStringMapFn("text_encoding", encodingNames, "unknown", d.U8, decode.NumberDecimal)
|
|
fieldTextNull(d, "description", int(encoding))
|
|
fieldText(d, "value", 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?
|
|
fieldTextNull(d, "owner", int(encodingISO8859_1))
|
|
d.FieldBitBufLen("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 id[0] == 'T':
|
|
idNormalized = "T000"
|
|
}
|
|
|
|
if unsyncFlag {
|
|
// TODO: DecodeFn
|
|
// TODO: unknown after frame decode
|
|
unsyncedBb := decode.MustNewBitBufFromReader(unsyncReader{Reader: d.BitBufRange(d.Pos(), int64(dataSize)*8)})
|
|
d.FieldFormatBitBuf("unsync", unsyncedBb, decode.FormatFn(func(d *decode.D, in interface{}) interface{} {
|
|
if fn, ok := frames[idNormalized]; ok {
|
|
fn(d)
|
|
} else {
|
|
d.FieldBitBufLen("data", d.BitsLeft())
|
|
}
|
|
|
|
return nil
|
|
}))
|
|
d.FieldBitBufLen("data", int64(dataSize*8))
|
|
} else {
|
|
if fn, ok := frames[idNormalized]; ok {
|
|
d.DecodeLenFn(int64(dataSize)*8, func(d *decode.D) {
|
|
fn(d)
|
|
})
|
|
} else {
|
|
d.FieldBitBufLen("data", int64(dataSize*8))
|
|
}
|
|
}
|
|
|
|
return size
|
|
}
|
|
|
|
func decodeFrames(d *decode.D, version int, size uint64) {
|
|
d.FieldArrayFn("frames", func(d *decode.D) {
|
|
for size > 0 {
|
|
if d.PeekBits(8) == 0 {
|
|
return
|
|
}
|
|
|
|
d.FieldStructFn("frame", func(d *decode.D) {
|
|
size -= decodeFrame(d, version)
|
|
})
|
|
}
|
|
|
|
})
|
|
|
|
if size > 0 {
|
|
d.FieldValidateZeroPadding("padding", int(size)*8)
|
|
}
|
|
}
|
|
|
|
func id3v2Decode(d *decode.D, in interface{}) interface{} {
|
|
d.ValidateAtLeastBitsLeft(4 * 8)
|
|
d.FieldValidateUTF8("magic", "ID3")
|
|
version := int(d.FieldU8("version"))
|
|
versionValid := version == 2 || version == 3 || version == 4
|
|
if !versionValid {
|
|
d.Invalid(fmt.Sprintf("unsupported version %d", version))
|
|
}
|
|
|
|
d.FieldU8("revision")
|
|
var extendedHeader bool
|
|
d.FieldStructFn("flags", func(d *decode.D) {
|
|
d.FieldBool("unsynchronisation")
|
|
extendedHeader = d.FieldBool("extended_header")
|
|
d.FieldBool("experimental_indicator")
|
|
d.FieldU5("unused")
|
|
})
|
|
size := d.FieldUFn("size", func() (uint64, decode.DisplayFormat, string) {
|
|
return syncSafeU32(d), decode.NumberDecimal, ""
|
|
})
|
|
|
|
var extHeaderSize uint64
|
|
if extendedHeader {
|
|
d.FieldStructFn("extended_header", func(d *decode.D) {
|
|
switch version {
|
|
case 3:
|
|
extHeaderSize = d.FieldU32("size")
|
|
d.FieldBitBufLen("data", int64(extHeaderSize)*8)
|
|
case 4:
|
|
extHeaderSize = d.FieldUFn("size", func() (uint64, decode.DisplayFormat, string) {
|
|
return syncSafeU32(d), decode.NumberDecimal, ""
|
|
})
|
|
// in v4 synchsafe integer includes itself
|
|
d.FieldBitBufLen("data", (int64(extHeaderSize)-4)*8)
|
|
}
|
|
})
|
|
}
|
|
|
|
decodeFrames(d, version, size)
|
|
|
|
return nil
|
|
}
|