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mp3file.js
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mp3file.js
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Mad.MP3File = function(stream) {
this.stream = stream;
}
Mad.MP3File.prototype.getID3v2Header = function() {
if (this.stream.get(0, 3) == "ID3") {
var headerStream = new Mad.SubStream(this.stream, 0, 10);
headerStream.read(3); // 'ID3'
var major = headerStream.readU8();
var minor = headerStream.readU8();
var flags = headerStream.readU8();
var length = headerStream.readSyncInteger();
return { version: '2.' + major + '.' + minor, major: major, minor: minor, flags: flags, length: length };
} else {
return null;
}
}
Mad.MP3File.prototype.getID3v2Stream = function() {
var header = this.getID3v2Header();
if (header) {
if (header.major > 2) {
return new Mad.ID3v23Stream(header, new Mad.SubStream(this.stream, 10, header.length));
} else {
return new Mad.ID3v22Stream(header, new Mad.SubStream(this.stream, 10, header.length));
}
} else {
return null;
}
}
Mad.MP3File.prototype.getMpegStream = function() {
var id3header = this.getID3v2Header();
if (id3header) {
var offset = 10 + id3header.length;
} else {
var offset = 0;
}
var length = this.stream.length - offset;
return new Mad.Stream(new Mad.SubStream(this.stream, offset), length);
}