mirror of
https://github.com/wader/fq.git
synced 2024-11-23 18:56:52 +03:00
e9d9f8aef9
Rename s/interface{}/any/g
Preparation for using generics in decode API and native jq funcations etc
Remove some unused linter ignores as linter has been fixed
627 lines
18 KiB
Go
627 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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"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.StrToDescription{
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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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"EQU": "Equalization",
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"ETC": "Event timing codes",
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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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"AENC": "Audio encryption",
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"APIC": "Attached picture",
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"ASPI": "Audio seek point index",
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"CHAP": "Chapter",
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"COMM": "Comments",
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"COMR": "Commercial frame",
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"CTOC": "Table of contents",
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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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}
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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: "utf16",
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encodingUTF16BE: "utf16be",
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encodingUTF8: "utf8",
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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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// id3v2.0
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// Attached picture "PIC"
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// Frame size $xx xx xx
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// Text encoding $xx
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// Image format $xx xx xx
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// Picture type $xx
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// Description <textstring> $00 (00)
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// Picture data <binary data>
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"PIC": func(d *decode.D) {
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encoding := d.FieldU8("text_encoding", encodingNames)
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d.FieldUTF8("image_format", 3)
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d.FieldU8("picture_type") // TODO: table
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d.FieldStrFn("description", textNullFn(int(encoding)))
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d.FieldFormatOrRawLen("picture", d.BitsLeft(), imageFormat, nil)
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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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d.FieldFormatOrRawLen("picture", d.BitsLeft(), imageFormat, nil)
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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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d.FieldFormatOrRawLen("data", d.BitsLeft(), imageFormat, nil)
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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)
|
|
// 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 any) any {
|
|
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 any) any {
|
|
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
|
|
}
|