525 lines
22 KiB
JavaScript
525 lines
22 KiB
JavaScript
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"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.MpegParser = void 0;
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const Token = require("token-types");
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const core_1 = require("strtok3/lib/core");
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const debug_1 = require("debug");
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const common = require("../common/Util");
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const AbstractID3Parser_1 = require("../id3v2/AbstractID3Parser");
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const XingTag_1 = require("./XingTag");
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const debug = (0, debug_1.default)('music-metadata:parser:mpeg');
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/**
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* Cache buffer size used for searching synchronization preabmle
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*/
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const maxPeekLen = 1024;
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/**
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* MPEG-4 Audio definitions
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* Ref: https://wiki.multimedia.cx/index.php/MPEG-4_Audio
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*/
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const MPEG4 = {
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/**
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* Audio Object Types
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*/
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AudioObjectTypes: [
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'AAC Main',
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'AAC LC',
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'AAC SSR',
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'AAC LTP' // Long Term Prediction
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],
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/**
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* Sampling Frequencies
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* https://wiki.multimedia.cx/index.php/MPEG-4_Audio#Sampling_Frequencies
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*/
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SamplingFrequencies: [
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96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000, 7350, undefined, undefined, -1
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]
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/**
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* Channel Configurations
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*/
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};
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const MPEG4_ChannelConfigurations = [
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undefined,
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['front-center'],
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['front-left', 'front-right'],
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['front-center', 'front-left', 'front-right'],
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['front-center', 'front-left', 'front-right', 'back-center'],
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['front-center', 'front-left', 'front-right', 'back-left', 'back-right'],
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['front-center', 'front-left', 'front-right', 'back-left', 'back-right', 'LFE-channel'],
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['front-center', 'front-left', 'front-right', 'side-left', 'side-right', 'back-left', 'back-right', 'LFE-channel']
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];
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/**
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* MPEG Audio Layer I/II/III frame header
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* Ref: https://www.mp3-tech.org/programmer/frame_header.html
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* Bit layout: AAAAAAAA AAABBCCD EEEEFFGH IIJJKLMM
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* Ref: https://wiki.multimedia.cx/index.php/ADTS
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*/
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class MpegFrameHeader {
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constructor(buf, off) {
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// B(20,19): MPEG Audio versionIndex ID
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this.versionIndex = common.getBitAllignedNumber(buf, off + 1, 3, 2);
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// C(18,17): Layer description
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this.layer = MpegFrameHeader.LayerDescription[common.getBitAllignedNumber(buf, off + 1, 5, 2)];
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if (this.versionIndex > 1 && this.layer === 0) {
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this.parseAdtsHeader(buf, off); // Audio Data Transport Stream (ADTS)
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}
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else {
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this.parseMpegHeader(buf, off); // Conventional MPEG header
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}
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// D(16): Protection bit (if true 16-bit CRC follows header)
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this.isProtectedByCRC = !common.isBitSet(buf, off + 1, 7);
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}
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calcDuration(numFrames) {
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return numFrames * this.calcSamplesPerFrame() / this.samplingRate;
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}
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calcSamplesPerFrame() {
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return MpegFrameHeader.samplesInFrameTable[this.version === 1 ? 0 : 1][this.layer];
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}
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calculateSideInfoLength() {
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if (this.layer !== 3)
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return 2;
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if (this.channelModeIndex === 3) {
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// mono
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if (this.version === 1) {
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return 17;
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}
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else if (this.version === 2 || this.version === 2.5) {
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return 9;
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}
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}
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else {
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if (this.version === 1) {
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return 32;
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}
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else if (this.version === 2 || this.version === 2.5) {
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return 17;
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}
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}
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}
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calcSlotSize() {
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return [null, 4, 1, 1][this.layer];
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}
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parseMpegHeader(buf, off) {
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this.container = 'MPEG';
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// E(15,12): Bitrate index
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this.bitrateIndex = common.getBitAllignedNumber(buf, off + 2, 0, 4);
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// F(11,10): Sampling rate frequency index
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this.sampRateFreqIndex = common.getBitAllignedNumber(buf, off + 2, 4, 2);
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// G(9): Padding bit
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this.padding = common.isBitSet(buf, off + 2, 6);
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// H(8): Private bit
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this.privateBit = common.isBitSet(buf, off + 2, 7);
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// I(7,6): Channel Mode
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this.channelModeIndex = common.getBitAllignedNumber(buf, off + 3, 0, 2);
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// J(5,4): Mode extension (Only used in Joint stereo)
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this.modeExtension = common.getBitAllignedNumber(buf, off + 3, 2, 2);
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// K(3): Copyright
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this.isCopyrighted = common.isBitSet(buf, off + 3, 4);
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// L(2): Original
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this.isOriginalMedia = common.isBitSet(buf, off + 3, 5);
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// M(3): The original bit indicates, if it is set, that the frame is located on its original media.
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this.emphasis = common.getBitAllignedNumber(buf, off + 3, 7, 2);
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this.version = MpegFrameHeader.VersionID[this.versionIndex];
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this.channelMode = MpegFrameHeader.ChannelMode[this.channelModeIndex];
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this.codec = `MPEG ${this.version} Layer ${this.layer}`;
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// Calculate bitrate
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const bitrateInKbps = this.calcBitrate();
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if (!bitrateInKbps) {
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throw new Error('Cannot determine bit-rate');
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}
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this.bitrate = bitrateInKbps * 1000;
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// Calculate sampling rate
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this.samplingRate = this.calcSamplingRate();
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if (this.samplingRate == null) {
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throw new Error('Cannot determine sampling-rate');
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}
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}
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parseAdtsHeader(buf, off) {
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debug(`layer=0 => ADTS`);
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this.version = this.versionIndex === 2 ? 4 : 2;
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this.container = 'ADTS/MPEG-' + this.version;
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const profileIndex = common.getBitAllignedNumber(buf, off + 2, 0, 2);
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this.codec = 'AAC';
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this.codecProfile = MPEG4.AudioObjectTypes[profileIndex];
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debug(`MPEG-4 audio-codec=${this.codec}`);
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const samplingFrequencyIndex = common.getBitAllignedNumber(buf, off + 2, 2, 4);
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this.samplingRate = MPEG4.SamplingFrequencies[samplingFrequencyIndex];
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debug(`sampling-rate=${this.samplingRate}`);
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const channelIndex = common.getBitAllignedNumber(buf, off + 2, 7, 3);
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this.mp4ChannelConfig = MPEG4_ChannelConfigurations[channelIndex];
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debug(`channel-config=${this.mp4ChannelConfig.join('+')}`);
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this.frameLength = common.getBitAllignedNumber(buf, off + 3, 6, 2) << 11;
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}
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calcBitrate() {
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if (this.bitrateIndex === 0x00 || // free
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this.bitrateIndex === 0x0F) { // reserved
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return;
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}
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const codecIndex = `${Math.floor(this.version)}${this.layer}`;
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return MpegFrameHeader.bitrate_index[this.bitrateIndex][codecIndex];
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}
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calcSamplingRate() {
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if (this.sampRateFreqIndex === 0x03)
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return null; // 'reserved'
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return MpegFrameHeader.sampling_rate_freq_index[this.version][this.sampRateFreqIndex];
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}
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}
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MpegFrameHeader.SyncByte1 = 0xFF;
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MpegFrameHeader.SyncByte2 = 0xE0;
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MpegFrameHeader.VersionID = [2.5, null, 2, 1];
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MpegFrameHeader.LayerDescription = [0, 3, 2, 1];
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MpegFrameHeader.ChannelMode = ['stereo', 'joint_stereo', 'dual_channel', 'mono'];
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MpegFrameHeader.bitrate_index = {
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0x01: { 11: 32, 12: 32, 13: 32, 21: 32, 22: 8, 23: 8 },
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0x02: { 11: 64, 12: 48, 13: 40, 21: 48, 22: 16, 23: 16 },
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0x03: { 11: 96, 12: 56, 13: 48, 21: 56, 22: 24, 23: 24 },
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0x04: { 11: 128, 12: 64, 13: 56, 21: 64, 22: 32, 23: 32 },
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0x05: { 11: 160, 12: 80, 13: 64, 21: 80, 22: 40, 23: 40 },
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0x06: { 11: 192, 12: 96, 13: 80, 21: 96, 22: 48, 23: 48 },
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0x07: { 11: 224, 12: 112, 13: 96, 21: 112, 22: 56, 23: 56 },
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0x08: { 11: 256, 12: 128, 13: 112, 21: 128, 22: 64, 23: 64 },
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0x09: { 11: 288, 12: 160, 13: 128, 21: 144, 22: 80, 23: 80 },
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0x0A: { 11: 320, 12: 192, 13: 160, 21: 160, 22: 96, 23: 96 },
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0x0B: { 11: 352, 12: 224, 13: 192, 21: 176, 22: 112, 23: 112 },
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0x0C: { 11: 384, 12: 256, 13: 224, 21: 192, 22: 128, 23: 128 },
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0x0D: { 11: 416, 12: 320, 13: 256, 21: 224, 22: 144, 23: 144 },
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0x0E: { 11: 448, 12: 384, 13: 320, 21: 256, 22: 160, 23: 160 }
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};
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MpegFrameHeader.sampling_rate_freq_index = {
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1: { 0x00: 44100, 0x01: 48000, 0x02: 32000 },
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2: { 0x00: 22050, 0x01: 24000, 0x02: 16000 },
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2.5: { 0x00: 11025, 0x01: 12000, 0x02: 8000 }
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};
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MpegFrameHeader.samplesInFrameTable = [
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/* Layer I II III */
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[0, 384, 1152, 1152],
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[0, 384, 1152, 576] // MPEG-2(.5
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];
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/**
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* MPEG Audio Layer I/II/III
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*/
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const FrameHeader = {
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len: 4,
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get: (buf, off) => {
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return new MpegFrameHeader(buf, off);
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}
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};
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function getVbrCodecProfile(vbrScale) {
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return 'V' + Math.floor((100 - vbrScale) / 10);
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}
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class MpegParser extends AbstractID3Parser_1.AbstractID3Parser {
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constructor() {
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super(...arguments);
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this.frameCount = 0;
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this.syncFrameCount = -1;
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this.countSkipFrameData = 0;
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this.totalDataLength = 0;
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this.bitrates = [];
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this.calculateEofDuration = false;
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this.buf_frame_header = Buffer.alloc(4);
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this.syncPeek = {
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buf: Buffer.alloc(maxPeekLen),
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len: 0
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};
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}
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/**
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* Called after ID3 headers have been parsed
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*/
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async postId3v2Parse() {
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this.metadata.setFormat('lossless', false);
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try {
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let quit = false;
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while (!quit) {
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await this.sync();
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quit = await this.parseCommonMpegHeader();
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}
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}
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catch (err) {
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if (err instanceof core_1.EndOfStreamError) {
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debug(`End-of-stream`);
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if (this.calculateEofDuration) {
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const numberOfSamples = this.frameCount * this.samplesPerFrame;
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this.metadata.setFormat('numberOfSamples', numberOfSamples);
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const duration = numberOfSamples / this.metadata.format.sampleRate;
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debug(`Calculate duration at EOF: ${duration} sec.`, duration);
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this.metadata.setFormat('duration', duration);
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}
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}
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else {
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throw err;
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}
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}
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}
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/**
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* Called after file has been fully parsed, this allows, if present, to exclude the ID3v1.1 header length
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*/
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finalize() {
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const format = this.metadata.format;
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const hasID3v1 = this.metadata.native.hasOwnProperty('ID3v1');
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if (format.duration && this.tokenizer.fileInfo.size) {
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const mpegSize = this.tokenizer.fileInfo.size - this.mpegOffset - (hasID3v1 ? 128 : 0);
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if (format.codecProfile && format.codecProfile[0] === 'V') {
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this.metadata.setFormat('bitrate', mpegSize * 8 / format.duration);
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}
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}
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else if (this.tokenizer.fileInfo.size && format.codecProfile === 'CBR') {
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const mpegSize = this.tokenizer.fileInfo.size - this.mpegOffset - (hasID3v1 ? 128 : 0);
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const numberOfSamples = Math.round(mpegSize / this.frame_size) * this.samplesPerFrame;
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this.metadata.setFormat('numberOfSamples', numberOfSamples);
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const duration = numberOfSamples / format.sampleRate;
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debug("Calculate CBR duration based on file size: %s", duration);
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this.metadata.setFormat('duration', duration);
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}
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}
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async sync() {
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let gotFirstSync = false;
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while (true) {
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let bo = 0;
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this.syncPeek.len = await this.tokenizer.peekBuffer(this.syncPeek.buf, { length: maxPeekLen, mayBeLess: true });
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if (this.syncPeek.len <= 163) {
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throw new core_1.EndOfStreamError();
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}
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while (true) {
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if (gotFirstSync && (this.syncPeek.buf[bo] & 0xE0) === 0xE0) {
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this.buf_frame_header[0] = MpegFrameHeader.SyncByte1;
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this.buf_frame_header[1] = this.syncPeek.buf[bo];
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await this.tokenizer.ignore(bo);
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debug(`Sync at offset=${this.tokenizer.position - 1}, frameCount=${this.frameCount}`);
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if (this.syncFrameCount === this.frameCount) {
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debug(`Re-synced MPEG stream, frameCount=${this.frameCount}`);
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this.frameCount = 0;
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this.frame_size = 0;
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}
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this.syncFrameCount = this.frameCount;
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return; // sync
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}
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else {
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gotFirstSync = false;
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bo = this.syncPeek.buf.indexOf(MpegFrameHeader.SyncByte1, bo);
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if (bo === -1) {
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if (this.syncPeek.len < this.syncPeek.buf.length) {
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throw new core_1.EndOfStreamError();
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}
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await this.tokenizer.ignore(this.syncPeek.len);
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break; // continue with next buffer
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}
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else {
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++bo;
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gotFirstSync = true;
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}
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}
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}
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}
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}
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/**
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* Combined ADTS & MPEG (MP2 & MP3) header handling
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* @return {Promise<boolean>} true if parser should quit
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*/
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async parseCommonMpegHeader() {
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if (this.frameCount === 0) {
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this.mpegOffset = this.tokenizer.position - 1;
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}
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await this.tokenizer.peekBuffer(this.buf_frame_header, { offset: 1, length: 3 });
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let header;
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try {
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header = FrameHeader.get(this.buf_frame_header, 0);
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}
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catch (err) {
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await this.tokenizer.ignore(1);
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this.metadata.addWarning('Parse error: ' + err.message);
|
||
|
|
return false; // sync
|
||
|
|
}
|
||
|
|
await this.tokenizer.ignore(3);
|
||
|
|
this.metadata.setFormat('container', header.container);
|
||
|
|
this.metadata.setFormat('codec', header.codec);
|
||
|
|
this.metadata.setFormat('lossless', false);
|
||
|
|
this.metadata.setFormat('sampleRate', header.samplingRate);
|
||
|
|
this.frameCount++;
|
||
|
|
return header.version >= 2 && header.layer === 0 ? this.parseAdts(header) : this.parseAudioFrameHeader(header);
|
||
|
|
}
|
||
|
|
/**
|
||
|
|
* @return {Promise<boolean>} true if parser should quit
|
||
|
|
*/
|
||
|
|
async parseAudioFrameHeader(header) {
|
||
|
|
this.metadata.setFormat('numberOfChannels', header.channelMode === 'mono' ? 1 : 2);
|
||
|
|
this.metadata.setFormat('bitrate', header.bitrate);
|
||
|
|
if (this.frameCount < 20 * 10000) {
|
||
|
|
debug('offset=%s MP%s bitrate=%s sample-rate=%s', this.tokenizer.position - 4, header.layer, header.bitrate, header.samplingRate);
|
||
|
|
}
|
||
|
|
const slot_size = header.calcSlotSize();
|
||
|
|
if (slot_size === null) {
|
||
|
|
throw new Error('invalid slot_size');
|
||
|
|
}
|
||
|
|
const samples_per_frame = header.calcSamplesPerFrame();
|
||
|
|
debug(`samples_per_frame=${samples_per_frame}`);
|
||
|
|
const bps = samples_per_frame / 8.0;
|
||
|
|
const fsize = (bps * header.bitrate / header.samplingRate) +
|
||
|
|
((header.padding) ? slot_size : 0);
|
||
|
|
this.frame_size = Math.floor(fsize);
|
||
|
|
this.audioFrameHeader = header;
|
||
|
|
this.bitrates.push(header.bitrate);
|
||
|
|
// xtra header only exists in first frame
|
||
|
|
if (this.frameCount === 1) {
|
||
|
|
this.offset = FrameHeader.len;
|
||
|
|
await this.skipSideInformation();
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
if (this.frameCount === 3) {
|
||
|
|
// the stream is CBR if the first 3 frame bitrates are the same
|
||
|
|
if (this.areAllSame(this.bitrates)) {
|
||
|
|
// Actual calculation will be done in finalize
|
||
|
|
this.samplesPerFrame = samples_per_frame;
|
||
|
|
this.metadata.setFormat('codecProfile', 'CBR');
|
||
|
|
if (this.tokenizer.fileInfo.size)
|
||
|
|
return true; // Will calculate duration based on the file size
|
||
|
|
}
|
||
|
|
else if (this.metadata.format.duration) {
|
||
|
|
return true; // We already got the duration, stop processing MPEG stream any further
|
||
|
|
}
|
||
|
|
if (!this.options.duration) {
|
||
|
|
return true; // Enforce duration not enabled, stop processing entire stream
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// once we know the file is VBR attach listener to end of
|
||
|
|
// stream so we can do the duration calculation when we
|
||
|
|
// have counted all the frames
|
||
|
|
if (this.options.duration && this.frameCount === 4) {
|
||
|
|
this.samplesPerFrame = samples_per_frame;
|
||
|
|
this.calculateEofDuration = true;
|
||
|
|
}
|
||
|
|
this.offset = 4;
|
||
|
|
if (header.isProtectedByCRC) {
|
||
|
|
await this.parseCrc();
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
await this.skipSideInformation();
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
async parseAdts(header) {
|
||
|
|
const buf = Buffer.alloc(3);
|
||
|
|
await this.tokenizer.readBuffer(buf);
|
||
|
|
header.frameLength += common.getBitAllignedNumber(buf, 0, 0, 11);
|
||
|
|
this.totalDataLength += header.frameLength;
|
||
|
|
this.samplesPerFrame = 1024;
|
||
|
|
const framesPerSec = header.samplingRate / this.samplesPerFrame;
|
||
|
|
const bytesPerFrame = this.frameCount === 0 ? 0 : this.totalDataLength / this.frameCount;
|
||
|
|
const bitrate = 8 * bytesPerFrame * framesPerSec + 0.5;
|
||
|
|
this.metadata.setFormat('bitrate', bitrate);
|
||
|
|
debug(`frame-count=${this.frameCount}, size=${header.frameLength} bytes, bit-rate=${bitrate}`);
|
||
|
|
await this.tokenizer.ignore(header.frameLength > 7 ? header.frameLength - 7 : 1);
|
||
|
|
// Consume remaining header and frame data
|
||
|
|
if (this.frameCount === 3) {
|
||
|
|
this.metadata.setFormat('codecProfile', header.codecProfile);
|
||
|
|
if (header.mp4ChannelConfig) {
|
||
|
|
this.metadata.setFormat('numberOfChannels', header.mp4ChannelConfig.length);
|
||
|
|
}
|
||
|
|
if (this.options.duration) {
|
||
|
|
this.calculateEofDuration = true;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
return true; // Stop parsing after the third frame
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
async parseCrc() {
|
||
|
|
this.crc = await this.tokenizer.readNumber(Token.INT16_BE);
|
||
|
|
this.offset += 2;
|
||
|
|
return this.skipSideInformation();
|
||
|
|
}
|
||
|
|
async skipSideInformation() {
|
||
|
|
const sideinfo_length = this.audioFrameHeader.calculateSideInfoLength();
|
||
|
|
// side information
|
||
|
|
await this.tokenizer.readToken(new Token.Uint8ArrayType(sideinfo_length));
|
||
|
|
this.offset += sideinfo_length;
|
||
|
|
await this.readXtraInfoHeader();
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
async readXtraInfoHeader() {
|
||
|
|
const headerTag = await this.tokenizer.readToken(XingTag_1.InfoTagHeaderTag);
|
||
|
|
this.offset += XingTag_1.InfoTagHeaderTag.len; // 12
|
||
|
|
switch (headerTag) {
|
||
|
|
case 'Info':
|
||
|
|
this.metadata.setFormat('codecProfile', 'CBR');
|
||
|
|
return this.readXingInfoHeader();
|
||
|
|
case 'Xing':
|
||
|
|
const infoTag = await this.readXingInfoHeader();
|
||
|
|
const codecProfile = getVbrCodecProfile(infoTag.vbrScale);
|
||
|
|
this.metadata.setFormat('codecProfile', codecProfile);
|
||
|
|
return null;
|
||
|
|
case 'Xtra':
|
||
|
|
// ToDo: ???
|
||
|
|
break;
|
||
|
|
case 'LAME':
|
||
|
|
const version = await this.tokenizer.readToken(XingTag_1.LameEncoderVersion);
|
||
|
|
if (this.frame_size >= this.offset + XingTag_1.LameEncoderVersion.len) {
|
||
|
|
this.offset += XingTag_1.LameEncoderVersion.len;
|
||
|
|
this.metadata.setFormat('tool', 'LAME ' + version);
|
||
|
|
await this.skipFrameData(this.frame_size - this.offset);
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
this.metadata.addWarning('Corrupt LAME header');
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
// ToDo: ???
|
||
|
|
}
|
||
|
|
// ToDo: promise duration???
|
||
|
|
const frameDataLeft = this.frame_size - this.offset;
|
||
|
|
if (frameDataLeft < 0) {
|
||
|
|
this.metadata.addWarning('Frame ' + this.frameCount + 'corrupt: negative frameDataLeft');
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
await this.skipFrameData(frameDataLeft);
|
||
|
|
}
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
/**
|
||
|
|
* Ref: http://gabriel.mp3-tech.org/mp3infotag.html
|
||
|
|
* @returns {Promise<string>}
|
||
|
|
*/
|
||
|
|
async readXingInfoHeader() {
|
||
|
|
const offset = this.tokenizer.position;
|
||
|
|
const infoTag = await (0, XingTag_1.readXingHeader)(this.tokenizer);
|
||
|
|
this.offset += this.tokenizer.position - offset;
|
||
|
|
if (infoTag.lame) {
|
||
|
|
this.metadata.setFormat('tool', 'LAME ' + common.stripNulls(infoTag.lame.version));
|
||
|
|
if (infoTag.lame.extended) {
|
||
|
|
// this.metadata.setFormat('trackGain', infoTag.lame.extended.track_gain);
|
||
|
|
this.metadata.setFormat('trackPeakLevel', infoTag.lame.extended.track_peak);
|
||
|
|
if (infoTag.lame.extended.track_gain) {
|
||
|
|
this.metadata.setFormat('trackGain', infoTag.lame.extended.track_gain.adjustment);
|
||
|
|
}
|
||
|
|
if (infoTag.lame.extended.album_gain) {
|
||
|
|
this.metadata.setFormat('albumGain', infoTag.lame.extended.album_gain.adjustment);
|
||
|
|
}
|
||
|
|
this.metadata.setFormat('duration', infoTag.lame.extended.music_length / 1000);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (infoTag.streamSize) {
|
||
|
|
const duration = this.audioFrameHeader.calcDuration(infoTag.numFrames);
|
||
|
|
this.metadata.setFormat('duration', duration);
|
||
|
|
debug('Get duration from Xing header: %s', this.metadata.format.duration);
|
||
|
|
return infoTag;
|
||
|
|
}
|
||
|
|
// frames field is not present
|
||
|
|
const frameDataLeft = this.frame_size - this.offset;
|
||
|
|
await this.skipFrameData(frameDataLeft);
|
||
|
|
return infoTag;
|
||
|
|
}
|
||
|
|
async skipFrameData(frameDataLeft) {
|
||
|
|
if (frameDataLeft < 0)
|
||
|
|
throw new Error('frame-data-left cannot be negative');
|
||
|
|
await this.tokenizer.ignore(frameDataLeft);
|
||
|
|
this.countSkipFrameData += frameDataLeft;
|
||
|
|
}
|
||
|
|
areAllSame(array) {
|
||
|
|
const first = array[0];
|
||
|
|
return array.every(element => {
|
||
|
|
return element === first;
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
exports.MpegParser = MpegParser;
|