１つの作業を完了しないと、次の作業に進むことが出来ない、ユゲタです。
現在、mp3ファイルをjavascriptで扱っているシステムを作っているんですが、
mp3ファイルには、id3タグという、曲名やアーティスト名などを格納している領域があり、
ファイル名ではなく、ちゃんと音楽データを管理する仕組みがあります。
このid3タグを取り出すには、ファイルのバイナリデータから取り出すしか方法がないため、
javascriptでは、普段あまり行わない操作に戸惑いながら、データ取得をしたという話です。
id3タグについて
id3のバージョンは、今現在以下の４つが存在します。
id3v1
id3v2.2
id3v2.3
id3v2.4
id3というのが、タグデータの名称だとすると、v1はバージョン１でv2がバージョン２ということのようですが、v2.2,v2.3,v2.4は、バージョン2.2 , 2.3 , 2.4という事ではなく、idv2のメジャーバージョン2 , 3 , 4という事なのだそうです。
この時点で全く意味不明な感じですが、まあ、とりあえず、v1,v2,v3,v4という風に考えるのがいいそうです。
そして、これらのバージョンはv1とv2はそれぞれフォーマットが全く違っていて、v2のそれぞれのメジャーバージョンも、ヘッダのデータフォーマットが一緒だけど、内容はまるで違っているという曲者なのです。
詳しくは、下記にリンクをつけてる参考ページを見てもらえると説明されています。
id3v1の解析コード
とりあえず、まずは、idv3v1のデータを取得してみたいと思います。
mp3_id3 = (function(){
var LIB = function(){};
LIB.prototype.bin2str = function(arr){
var str = "";
for(var i in arr){
str += String.fromCharCode(arr[i]);
}
str = str.replace(/\u000f/g , "");
return str;
};
// @ [0,1,2,3]
LIB.prototype.size_bit = function(datas , bit){
var num = 0;
for(var i=0; i<datas.length; i++){
var shift = (datas.length - 1 - i);
if(shift){
num += datas[i] << (bit * shift);
}
else{
num += datas[i];
}
}
return num;
};
LIB.prototype.getFrameKey = function(key){
for(var i in frame_arr){
if(frame_arr[i][0] === key){
return i;
}
else if(frame_arr[i][1] === key){
return i;
}
}
return key;
};
// LIB.prototype.getByteAt = function(iOffset) {
// return data.charCodeAt(iOffset + dataOffset) & 0xFF;
// };
var mp3_id3 = function(){};
mp3_id3.prototype.read = function(file , callback){
var reader = new FileReader();
reader.readAsArrayBuffer(file);
reader.onload = (function(e){
var target = e.target;
var res = this.v1(target.result , target.buffer);
callback(res);
}).bind(this);
};
// ----------
// id3v1
mp3_id3.prototype.v1 = function(binary){
if(!binary){return null;}
var data = (new Uint8Array(binary)).slice(-128);
if (data[0] + data[1] + data[2] !== 220) {return null}
var lib = new LIB();
return {
header : {
id : lib.bin2str(data.slice( 0, 0 + 3)),
type : 1,
version : (!data[127]) ? 0 : 1
},
frame : {
title : this.v1_str(data.slice( 3, 3 + 30)),
artist : this.v1_str(data.slice(33, 33 + 30)),
album : this.v1_str(data.slice(63, 63 + 30)),
year : lib.bin2str(data.slice(93, 93 + 4)),
comment : this.v1_str(data.slice(97, 97 + 30)),
track : data[126],
genre : data[127] && typeof v1_genre[data[127]] !== "undefined" ? v1_genre[data[127]] : data[127]
}
};
};
mp3_id3.prototype.v1_str = function(data){
var txt = new TextDecoder("SJIS");
return txt.decode(data);
}
var PICTURE_TYPES = {
"0": "Other",
"1": "32x32 pixels 'file icon' (PNG only)",
"2": "Other file icon",
"3": "Cover (front)",
"4": "Cover (back)",
"5": "Leaflet page",
"6": "Media (e.g. lable side of CD)",
"7": "Lead artist/lead performer/soloist",
"8": "Artist/performer",
"9": "Conductor",
A: "Band/Orchestra",
B: "Composer",
C: "Lyricist/text writer",
D: "Recording Location",
E: "During recording",
F: "During performance",
"10": "Movie/video screen capture",
"11": "A bright coloured fish", //<--- WTF?
"12": "Illustration",
"13": "Band/artist logotype",
"14": "Publisher/Studio logotype"
};
//from: http://bitbucket.org/moumar/ruby-mp3info/src/tip/lib/mp3info/id3v2.rb
//TODO: replace with something longer
var TAGS = {
AENC: "Audio encryption",
APIC: "Attached picture",
COMM: "Comments",
COMR: "Commercial frame",
ENCR: "Encryption method registration",
EQUA: "Equalization",
ETCO: "Event timing codes",
GEOB: "General encapsulated object",
GRID: "Group identification registration",
IPLS: "Involved people list",
LINK: "Linked information",
MCDI: "Music CD identifier",
MLLT: "MPEG location lookup table",
OWNE: "Ownership frame",
PRIV: "Private frame",
PCNT: "Play counter",
POPM: "Popularimeter",
POSS: "Position synchronisation frame",
RBUF: "Recommended buffer size",
RVAD: "Relative volume adjustment",
RVRB: "Reverb",
SYLT: "Synchronized lyric/text",
SYTC: "Synchronized tempo codes",
TALB: "Album",
TBPM: "BPM",
TCOM: "Composer",
TCON: "Genre",
TCOP: "Copyright message",
TDAT: "Date",
TDLY: "Playlist delay",
TENC: "Encoded by",
TEXT: "Lyricist",
TFLT: "File type",
TIME: "Time",
TIT1: "Content group description",
TIT2: "Title",
TIT3: "Subtitle",
TKEY: "Initial key",
TLAN: "Language(s)",
TLEN: "Length",
TMED: "Media type",
TOAL: "Original album",
TOFN: "Original filename",
TOLY: "Original lyricist",
TOPE: "Original artist",
TORY: "Original release year",
TOWN: "File owner",
TPE1: "Artist",
TPE2: "Band",
TPE3: "Conductor",
TPE4: "Interpreted, remixed, or otherwise modified by",
TPOS: "Part of a set",
TPUB: "Publisher",
TRCK: "Track number",
TRDA: "Recording dates",
TRSN: "Internet radio station name",
TRSO: "Internet radio station owner",
TSIZ: "Size",
TSRC: "ISRC (international standard recording code)",
TSSE: "Software/Hardware and settings used for encoding",
TYER: "Year",
TXXX: "User defined text information frame",
UFID: "Unique file identifier",
USER: "Terms of use",
USLT: "Unsychronized lyric/text transcription",
WCOM: "Commercial information",
WCOP: "Copyright/Legal information",
WOAF: "Official audio file webpage",
WOAR: "Official artist/performer webpage",
WOAS: "Official audio source webpage",
WORS: "Official internet radio station homepage",
WPAY: "Payment",
WPUB: "Publishers official webpage",
WXXX: "User defined URL link frame"
};
var TAG_MAPPING_2_2_to_2_3 = {
BUF: "RBUF",
COM: "COMM",
CRA: "AENC",
EQU: "EQUA",
ETC: "ETCO",
GEO: "GEOB",
MCI: "MCDI",
MLL: "MLLT",
PIC: "APIC",
POP: "POPM",
REV: "RVRB",
RVA: "RVAD",
SLT: "SYLT",
STC: "SYTC",
TAL: "TALB",
TBP: "TBPM",
TCM: "TCOM",
TCO: "TCON",
TCR: "TCOP",
TDA: "TDAT",
TDY: "TDLY",
TEN: "TENC",
TFT: "TFLT",
TIM: "TIME",
TKE: "TKEY",
TLA: "TLAN",
TLE: "TLEN",
TMT: "TMED",
TOA: "TOPE",
TOF: "TOFN",
TOL: "TOLY",
TOR: "TORY",
TOT: "TOAL",
TP1: "TPE1",
TP2: "TPE2",
TP3: "TPE3",
TP4: "TPE4",
TPA: "TPOS",
TPB: "TPUB",
TRC: "TSRC",
TRD: "TRDA",
TRK: "TRCK",
TSI: "TSIZ",
TSS: "TSSE",
TT1: "TIT1",
TT2: "TIT2",
TT3: "TIT3",
TXT: "TEXT",
TXX: "TXXX",
TYE: "TYER",
UFI: "UFID",
ULT: "USLT",
WAF: "WOAF",
WAR: "WOAR",
WAS: "WOAS",
WCM: "WCOM",
WCP: "WCOP",
WPB: "WPB",
WXX: "WXXX"
};
//pulled from http://www.id3.org/id3v2-00 and changed with a simple replace
//probably should be an array instead, but thats harder to convert -_-
var v1_genre = {
"0": "Blues",
"1": "Classic Rock",
"2": "Country",
"3": "Dance",
"4": "Disco",
"5": "Funk",
"6": "Grunge",
"7": "Hip-Hop",
"8": "Jazz",
"9": "Metal",
"10": "New Age",
"11": "Oldies",
"12": "Other",
"13": "Pop",
"14": "R&B",
"15": "Rap",
"16": "Reggae",
"17": "Rock",
"18": "Techno",
"19": "Industrial",
"20": "Alternative",
"21": "Ska",
"22": "Death Metal",
"23": "Pranks",
"24": "Soundtrack",
"25": "Euro-Techno",
"26": "Ambient",
"27": "Trip-Hop",
"28": "Vocal",
"29": "Jazz+Funk",
"30": "Fusion",
"31": "Trance",
"32": "Classical",
"33": "Instrumental",
"34": "Acid",
"35": "House",
"36": "Game",
"37": "Sound Clip",
"38": "Gospel",
"39": "Noise",
"40": "AlternRock",
"41": "Bass",
"42": "Soul",
"43": "Punk",
"44": "Space",
"45": "Meditative",
"46": "Instrumental Pop",
"47": "Instrumental Rock",
"48": "Ethnic",
"49": "Gothic",
"50": "Darkwave",
"51": "Techno-Industrial",
"52": "Electronic",
"53": "Pop-Folk",
"54": "Eurodance",
"55": "Dream",
"56": "Southern Rock",
"57": "Comedy",
"58": "Cult",
"59": "Gangsta",
"60": "Top 40",
"61": "Christian Rap",
"62": "Pop/Funk",
"63": "Jungle",
"64": "Native American",
"65": "Cabaret",
"66": "New Wave",
"67": "Psychadelic",
"68": "Rave",
"69": "Showtunes",
"70": "Trailer",
"71": "Lo-Fi",
"72": "Tribal",
"73": "Acid Punk",
"74": "Acid Jazz",
"75": "Polka",
"76": "Retro",
"77": "Musical",
"78": "Rock & Roll",
"79": "Hard Rock",
"80": "Folk",
"81": "Folk-Rock",
"82": "National Folk",
"83": "Swing",
"84": "Fast Fusion",
"85": "Bebob",
"86": "Latin",
"87": "Revival",
"88": "Celtic",
"89": "Bluegrass",
"90": "Avantgarde",
"91": "Gothic Rock",
"92": "Progressive Rock",
"93": "Psychedelic Rock",
"94": "Symphonic Rock",
"95": "Slow Rock",
"96": "Big Band",
"97": "Chorus",
"98": "Easy Listening",
"99": "Acoustic",
"100": "Humour",
"101": "Speech",
"102": "Chanson",
"103": "Opera",
"104": "Chamber Music",
"105": "Sonata",
"106": "Symphony",
"107": "Booty Bass",
"108": "Primus",
"109": "Porn Groove",
"110": "Satire",
"111": "Slow Jam",
"112": "Club",
"113": "Tango",
"114": "Samba",
"115": "Folklore",
"116": "Ballad",
"117": "Power Ballad",
"118": "Rhythmic Soul",
"119": "Freestyle",
"120": "Duet",
"121": "Punk Rock",
"122": "Drum Solo",
"123": "A capella",
"124": "Euro-House",
"125": "Dance Hall"
};
var _frames = {
// v2.2
"BUF" : "Recommended buffer size",
"CNT" : "Play counter",
"COM" : "Comments",
"CRA" : "Audio encryption",
"CRM" : "Encrypted meta frame",
"ETC" : "Event timing codes",
"EQU" : "Equalization",
"GEO" : "General encapsulated object",
"IPL" : "Involved people list",
"LNK" : "Linked information",
"MCI" : "Music CD Identifier",
"MLL" : "MPEG location lookup table",
"PIC" : "Attached picture",
"POP" : "Popularimeter",
"REV" : "Reverb",
"RVA" : "Relative volume adjustment",
"SLT" : "Synchronized lyric/text",
"STC" : "Synced tempo codes",
"TAL" : "Album/Movie/Show title",
"TBP" : "BPM (Beats Per Minute)",
"TCM" : "Composer",
"TCO" : "Content type",
"TCR" : "Copyright message",
"TDA" : "Date",
"TDY" : "Playlist delay",
"TEN" : "Encoded by",
"TFT" : "File type",
"TIM" : "Time",
"TKE" : "Initial key",
"TLA" : "Language(s)",
"TLE" : "Length",
"TMT" : "Media type",
"TOA" : "Original artist(s)/performer(s)",
"TOF" : "Original filename",
"TOL" : "Original Lyricist(s)/text writer(s)",
"TOR" : "Original release year",
"TOT" : "Original album/Movie/Show title",
"TP1" : "Lead artist(s)/Lead performer(s)/Soloist(s)/Performing group",
"TP2" : "Band/Orchestra/Accompaniment",
"TP3" : "Conductor/Performer refinement",
"TP4" : "Interpreted, remixed, or otherwise modified by",
"TPA" : "Part of a set",
"TPB" : "Publisher",
"TRC" : "ISRC (International Standard Recording Code)",
"TRD" : "Recording dates",
"TRK" : "Track number/Position in set",
"TSI" : "Size",
"TSS" : "Software/hardware and settings used for encoding",
"TT1" : "Content group description",
"TT2" : "Title/Songname/Content description",
"TT3" : "Subtitle/Description refinement",
"TXT" : "Lyricist/text writer",
"TXX" : "User defined text information frame",
"TYE" : "Year",
"UFI" : "Unique file identifier",
"ULT" : "Unsychronized lyric/text transcription",
"WAF" : "Official audio file webpage",
"WAR" : "Official artist/performer webpage",
"WAS" : "Official audio source webpage",
"WCM" : "Commercial information",
"WCP" : "Copyright/Legal information",
"WPB" : "Publishers official webpage",
"WXX" : "User defined URL link frame",
// v2.3
"AENC" : "Audio encryption",
"APIC" : "Attached picture",
"COMM" : "Comments",
"COMR" : "Commercial frame",
"ENCR" : "Encryption method registration",
"EQUA" : "Equalization",
"ETCO" : "Event timing codes",
"GEOB" : "General encapsulated object",
"GRID" : "Group identification registration",
"IPLS" : "Involved people list",
"LINK" : "Linked information",
"MCDI" : "Music CD identifier",
"MLLT" : "MPEG location lookup table",
"OWNE" : "Ownership frame",
"PRIV" : "Private frame",
"PCNT" : "Play counter",
"POPM" : "Popularimeter",
"POSS" : "Position synchronisation frame",
"RBUF" : "Recommended buffer size",
"RVAD" : "Relative volume adjustment",
"RVRB" : "Reverb",
"SYLT" : "Synchronized lyric/text",
"SYTC" : "Synchronized tempo codes",
"TALB" : "Album/Movie/Show title",
"TBPM" : "BPM (beats per minute)",
"TCOM" : "Composer",
"TCON" : "Content type",
"TCOP" : "Copyright message",
"TDAT" : "Date",
"TDLY" : "Playlist delay",
"TENC" : "Encoded by",
"TEXT" : "Lyricist/Text writer",
"TFLT" : "File type",
"TIME" : "Time",
"TIT1" : "Content group description",
"TIT2" : "Title/songname/content description",
"TIT3" : "Subtitle/Description refinement",
"TKEY" : "Initial key",
"TLAN" : "Language(s)",
"TLEN" : "Length",
"TMED" : "Media type",
"TOAL" : "Original album/movie/show title",
"TOFN" : "Original filename",
"TOLY" : "Original lyricist(s)/text writer(s)",
"TOPE" : "Original artist(s)/performer(s)",
"TORY" : "Original release year",
"TOWN" : "File owner/licensee",
"TPE1" : "Lead performer(s)/Soloist(s)",
"TPE2" : "Band/orchestra/accompaniment",
"TPE3" : "Conductor/performer refinement",
"TPE4" : "Interpreted, remixed, or otherwise modified by",
"TPOS" : "Part of a set",
"TPUB" : "Publisher",
"TRCK" : "Track number/Position in set",
"TRDA" : "Recording dates",
"TRSN" : "Internet radio station name",
"TRSO" : "Internet radio station owner",
"TSIZ" : "Size",
"TSRC" : "ISRC (international standard recording code)",
"TSSE" : "Software/Hardware and settings used for encoding",
"TYER" : "Year",
"TXXX" : "User defined text information frame",
"UFID" : "Unique file identifier",
"USER" : "Terms of use",
"USLT" : "Unsychronized lyric/text transcription",
"WCOM" : "Commercial information",
"WCOP" : "Copyright/Legal information",
"WOAF" : "Official audio file webpage",
"WOAR" : "Official artist/performer webpage",
"WOAS" : "Official audio source webpage",
"WORS" : "Official internet radio station homepage",
"WPAY" : "Payment",
"WPUB" : "Publishers official webpage",
"WXXX" : "User defined URL link frame"
};
var header_arr = [
"id",
"type",
"version",
"debug",
"flg",
"size"
];
var frame_arr = {
"title" : ["TIT2", "TT2"],
"artist" : ["TPE1", "TP1"],
"album" : ["TALB", "TAL"],
"year" : ["TYER", "TYE"],
"comment" : ["COMM", "COM"],
"track" : ["TRCK", "TRK"],
"genre" : ["TCON", "TCO"],
"picture" : ["APIC", "PIC"],
"lyrics" : ["USLT", "ULT"]
};
var _defaultShortcuts = ["title", "artist", "album", "track"];
return mp3_id3;
})();
無駄なデータも付与しているので、少し長めのコードになってしまいましたが、このライブラリをwebページのfileAPIと組み合わせると、id3v1のデータを取得できるようになっています。
使い方は、
var input = document.querySelector("input[type='file']");
for(var i=0; i<input.files.length; i++){
if(input.files[i].file.match(/\.mp3$/)){
new mp3_id3().read(input.files[i].file , function(data){
console.log(data);
});
}
}
inputタグのファイルをmp3ファイルである場合に、１つずつ送ることで、ファイル別にid3タグ情報を取得してくれます。
ただし、現在のソースでは、v1しか認識しないので、今後v2.2 v2.3 v2.4を追加していかなければいけませんね。
全部完成したら、githubにアップしますね・・・
まだまだ、果てしないゴールです・・・
参考
https://ja.wikipedia.org/wiki/ID3タグ
https://www.mp3tag.de/en/index.html
