Jigz
641 lines
22 KiB
TypeScript
641 lines
22 KiB
TypeScript
import initDebug from 'debug';
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import * as Token from 'token-types';
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import { BasicParser } from '../common/BasicParser.js';
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import { Genres } from '../id3v1/ID3v1Parser.js';
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import { Atom } from './Atom.js';
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import * as AtomToken from './AtomToken.js';
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import { Mp4ContentError } from './AtomToken.js';
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import { type AnyTagValue, type IChapter, type ITrackInfo, TrackType } from '../type.js';
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import type { IGetToken } from '@tokenizer/token';
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import { uint8ArrayToHex, uint8ArrayToString } from 'uint8array-extras';
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const debug = initDebug('music-metadata:parser:MP4');
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const tagFormat = 'iTunes';
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interface IEncoder {
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lossy: boolean;
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format: string;
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}
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interface ISoundSampleDescription {
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dataFormat: string;
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dataReferenceIndex: number;
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description?: {
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numAudioChannels: number;
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/**
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* Number of bits in each uncompressed sound sample
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*/
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sampleSize?: number;
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/**
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* Compression ID
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*/
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compressionId?: number;
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packetSize?: number;
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sampleRate: number;
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};
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}
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interface ITrackDescription extends AtomToken.ITrackHeaderAtom {
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soundSampleDescription: ISoundSampleDescription[];
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timeScale: number;
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chapterList: number[];
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chunkOffsetTable: number[];
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sampleSize: number;
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sampleSizeTable: number[];
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sampleToChunkTable: AtomToken.ISampleToChunk[];
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timeToSampleTable: AtomToken.ITimeToSampleToken[];
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}
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type IAtomParser = (payloadLength: number) => Promise<void>;
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const encoderDict: { [dataFormatId: string]: IEncoder; } = {
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raw: {
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lossy: false,
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format: 'raw'
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},
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MAC3: {
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lossy: true,
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format: 'MACE 3:1'
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},
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MAC6: {
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lossy: true,
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format: 'MACE 6:1'
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},
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ima4: {
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lossy: true,
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format: 'IMA 4:1'
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},
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ulaw: {
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lossy: true,
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format: 'uLaw 2:1'
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},
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alaw: {
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lossy: true,
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format: 'uLaw 2:1'
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},
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Qclp: {
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lossy: true,
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format: 'QUALCOMM PureVoice'
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},
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'.mp3': {
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lossy: true,
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format: 'MPEG-1 layer 3'
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},
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alac: {
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lossy: false,
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format: 'ALAC'
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},
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'ac-3': {
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lossy: true,
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format: 'AC-3'
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},
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mp4a: {
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lossy: true,
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format: 'MPEG-4/AAC'
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},
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mp4s: {
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lossy: true,
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format: 'MP4S'
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},
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// Closed Captioning Media, https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html#//apple_ref/doc/uid/TP40000939-CH205-SW87
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c608: {
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lossy: true,
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format: 'CEA-608'
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},
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c708: {
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lossy: true,
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format: 'CEA-708'
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}
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};
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function distinct(value: AnyTagValue, index: number, self: AnyTagValue[]) {
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return self.indexOf(value) === index;
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}
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/*
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* Parser for the MP4 (MPEG-4 Part 14) container format
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* Standard: ISO/IEC 14496-14
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* supporting:
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* - QuickTime container
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* - MP4 File Format
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* - 3GPP file format
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* - 3GPP2 file format
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*
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* MPEG-4 Audio / Part 3 (.m4a)& MPEG 4 Video (m4v, mp4) extension.
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* Support for Apple iTunes tags as found in a M4A/M4V files.
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* Ref:
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* https://en.wikipedia.org/wiki/ISO_base_media_file_format
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* https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/Metadata/Metadata.html
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* http://atomicparsley.sourceforge.net/mpeg-4files.html
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* https://github.com/sergiomb2/libmp4v2/wiki/iTunesMetadata
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* https://wiki.multimedia.cx/index.php/QuickTime_container
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*/
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export class MP4Parser extends BasicParser {
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private static read_BE_Integer(array: Uint8Array, signed: boolean): number {
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const integerType = (signed ? 'INT' : 'UINT') + array.length * 8 + (array.length > 1 ? '_BE' : '');
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const token: IGetToken<number | bigint> = (Token as unknown as { [id: string]: IGetToken<number | bigint> })[integerType];
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if (!token) {
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throw new Mp4ContentError(`Token for integer type not found: "${integerType}"`);
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}
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return Number(token.get(array, 0));
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}
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private audioLengthInBytes: number | undefined;
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private tracks: ITrackDescription[] = [];
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public async parse(): Promise<void> {
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this.tracks = [];
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let remainingFileSize = this.tokenizer.fileInfo.size || 0;
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while (!this.tokenizer.fileInfo.size || remainingFileSize > 0) {
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try {
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const token = await this.tokenizer.peekToken<AtomToken.IAtomHeader>(AtomToken.Header);
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if (token.name === '\0\0\0\0') {
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const errMsg = `Error at offset=${this.tokenizer.position}: box.id=0`;
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debug(errMsg);
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this.addWarning(errMsg);
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break;
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}
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} catch (error) {
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if (error instanceof Error) {
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const errMsg = `Error at offset=${this.tokenizer.position}: ${error.message}`;
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debug(errMsg);
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this.addWarning(errMsg);
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} else throw error;
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break;
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}
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const rootAtom = await Atom.readAtom(this.tokenizer, (atom, remaining) => this.handleAtom(atom, remaining), null, remainingFileSize);
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remainingFileSize -= rootAtom.header.length === BigInt(0) ? remainingFileSize : Number(rootAtom.header.length);
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}
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// Post process metadata
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const formatList: string[] = [];
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this.tracks.forEach(track => {
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const trackFormats: string[] = [];
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track.soundSampleDescription.forEach(ssd => {
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const streamInfo: ITrackInfo = {};
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const encoderInfo = encoderDict[ssd.dataFormat];
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if (encoderInfo) {
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trackFormats.push(encoderInfo.format);
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streamInfo.codecName = encoderInfo.format;
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} else {
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streamInfo.codecName = `<${ssd.dataFormat}>`;
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}
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if (ssd.description) {
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const {description} = ssd;
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if (description.sampleRate > 0) {
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streamInfo.type = TrackType.audio;
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streamInfo.audio = {
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samplingFrequency: description.sampleRate,
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bitDepth: description.sampleSize,
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channels: description.numAudioChannels
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};
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}
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}
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this.metadata.addStreamInfo(streamInfo);
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});
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if (trackFormats.length >= 1) {
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formatList.push(trackFormats.join('/'));
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}
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});
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if (formatList.length > 0) {
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this.metadata.setFormat('codec', formatList.filter(distinct).join('+'));
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}
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const audioTracks = this.tracks.filter(track => {
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return track.soundSampleDescription.length >= 1 && track.soundSampleDescription[0].description && track.soundSampleDescription[0].description.numAudioChannels > 0;
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});
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if (audioTracks.length >= 1) {
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const audioTrack = audioTracks[0];
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if (audioTrack.timeScale > 0) {
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const duration = audioTrack.duration / audioTrack.timeScale; // calculate duration in seconds
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this.metadata.setFormat('duration', duration);
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}
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const ssd = audioTrack.soundSampleDescription[0];
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if (ssd.description) {
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this.metadata.setFormat('sampleRate', ssd.description.sampleRate);
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this.metadata.setFormat('bitsPerSample', ssd.description.sampleSize);
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this.metadata.setFormat('numberOfChannels', ssd.description.numAudioChannels);
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if (audioTrack.timeScale === 0 && audioTrack.timeToSampleTable.length > 0) {
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const totalSampleSize = audioTrack.timeToSampleTable
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.map(ttstEntry => ttstEntry.count * ttstEntry.duration)
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.reduce((total, sampleSize) => total + sampleSize);
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const duration = totalSampleSize / ssd.description.sampleRate;
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this.metadata.setFormat('duration', duration);
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}
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}
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const encoderInfo = encoderDict[ssd.dataFormat];
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if (encoderInfo) {
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this.metadata.setFormat('lossless', !encoderInfo.lossy);
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}
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this.calculateBitRate();
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}
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}
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public async handleAtom(atom: Atom, remaining: number): Promise<void> {
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if (atom.parent) {
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switch (atom.parent.header.name) {
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case 'ilst':
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case '<id>':
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return this.parseMetadataItemData(atom);
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}
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}
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// const payloadLength = atom.getPayloadLength(remaining);
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if (this.atomParsers[atom.header.name]) {
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return this.atomParsers[atom.header.name](remaining);
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}
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debug(`No parser for atom path=${atom.atomPath}, payload-len=${remaining}, ignoring atom`);
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await this.tokenizer.ignore(remaining);
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}
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private getTrackDescription(): ITrackDescription {
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return this.tracks[this.tracks.length - 1];
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}
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private calculateBitRate() {
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if (this.audioLengthInBytes && this.metadata.format.duration) {
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this.metadata.setFormat('bitrate', 8 * this.audioLengthInBytes / this.metadata.format.duration);
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}
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}
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private async addTag(id: string, value: AnyTagValue): Promise<void> {
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await this.metadata.addTag(tagFormat, id, value);
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}
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private addWarning(message: string) {
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debug(`Warning: ${message}`);
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this.metadata.addWarning(message);
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}
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/**
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* Parse data of Meta-item-list-atom (item of 'ilst' atom)
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* @param metaAtom
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* Ref: https://developer.apple.com/library/content/documentation/QuickTime/QTFF/Metadata/Metadata.html#//apple_ref/doc/uid/TP40000939-CH1-SW8
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*/
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private parseMetadataItemData(metaAtom: Atom): Promise<void> {
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let tagKey = metaAtom.header.name;
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return metaAtom.readAtoms(this.tokenizer, async (child, remaining) => {
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const payLoadLength = child.getPayloadLength(remaining);
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switch (child.header.name) {
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case 'data': // value atom
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return this.parseValueAtom(tagKey, child);
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case 'name': // name atom (optional)
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case 'mean':
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case 'rate': {
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const name = await this.tokenizer.readToken<AtomToken.INameAtom>(new AtomToken.NameAtom(payLoadLength));
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tagKey += `:${name.name}`;
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break;
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}
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default: {
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const uint8Array = await this.tokenizer.readToken<Uint8Array>(new Token.Uint8ArrayType(payLoadLength));
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this.addWarning(`Unsupported meta-item: ${tagKey}[${child.header.name}] => value=${uint8ArrayToHex(uint8Array)} ascii=${uint8ArrayToString(uint8Array, 'ascii')}`);
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}
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}
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}, metaAtom.getPayloadLength(0));
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}
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private async parseValueAtom(tagKey: string, metaAtom: Atom): Promise<void> {
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const dataAtom = await this.tokenizer.readToken(new AtomToken.DataAtom(Number(metaAtom.header.length) - AtomToken.Header.len));
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if (dataAtom.type.set !== 0) {
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throw new Mp4ContentError(`Unsupported type-set != 0: ${dataAtom.type.set}`);
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}
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// Use well-known-type table
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// Ref: https://developer.apple.com/library/content/documentation/QuickTime/QTFF/Metadata/Metadata.html#//apple_ref/doc/uid/TP40000939-CH1-SW35
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switch (dataAtom.type.type) {
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case 0: // reserved: Reserved for use where no type needs to be indicated
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switch (tagKey) {
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case 'trkn':
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case 'disk': {
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const num = Token.UINT8.get(dataAtom.value, 3);
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const of = Token.UINT8.get(dataAtom.value, 5);
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// console.log(" %s[data] = %s/%s", tagKey, num, of);
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await this.addTag(tagKey, `${num}/${of}`);
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break;
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}
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case 'gnre': {
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const genreInt = Token.UINT8.get(dataAtom.value, 1);
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const genreStr = Genres[genreInt - 1];
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// console.log(" %s[data] = %s", tagKey, genreStr);
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await this.addTag(tagKey, genreStr);
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break;
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}
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case 'rate': {
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const rate = new TextDecoder('ascii').decode(dataAtom.value);
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await this.addTag(tagKey, rate);
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break;
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}
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default:
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debug(`unknown proprietary value type for: ${metaAtom.atomPath}`);
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}
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break;
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case 1: // UTF-8: Without any count or NULL terminator
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case 18: // Unknown: Found in m4b in combination with a '©gen' tag
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await this.addTag(tagKey, new TextDecoder('utf-8').decode(dataAtom.value));
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break;
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case 13: // JPEG
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if (this.options.skipCovers)
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break;
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await this.addTag(tagKey, {
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format: 'image/jpeg',
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data: Uint8Array.from(dataAtom.value)
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});
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break;
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case 14: // PNG
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if (this.options.skipCovers)
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break;
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await this.addTag(tagKey, {
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format: 'image/png',
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data: Uint8Array.from(dataAtom.value)
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});
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break;
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case 21: // BE Signed Integer
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await this.addTag(tagKey, MP4Parser.read_BE_Integer(dataAtom.value, true));
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break;
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case 22: // BE Unsigned Integer
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await this.addTag(tagKey, MP4Parser.read_BE_Integer(dataAtom.value, false));
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break;
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case 65: // An 8-bit signed integer
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await this.addTag(tagKey, Token.UINT8.get(dataAtom.value,0));
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break;
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case 66: // A big-endian 16-bit signed integer
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await this.addTag(tagKey, Token.UINT16_BE.get(dataAtom.value,0));
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break;
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case 67: // A big-endian 32-bit signed integer
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await this.addTag(tagKey, Token.UINT32_BE.get(dataAtom.value,0));
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break;
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default:
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this.addWarning(`atom key=${tagKey}, has unknown well-known-type (data-type): ${dataAtom.type.type}`);
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}
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}
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private atomParsers: { [id: string]: IAtomParser; } = {
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/**
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* Parse movie header (mvhd) atom
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* Ref: https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap2/qtff2.html#//apple_ref/doc/uid/TP40000939-CH204-56313
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*/
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mvhd: async (len: number) => {
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const mvhd = await this.tokenizer.readToken<AtomToken.IAtomMvhd>(new AtomToken.MvhdAtom(len));
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this.metadata.setFormat('creationTime', mvhd.creationTime);
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this.metadata.setFormat('modificationTime', mvhd.modificationTime);
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},
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/**
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* Parse media header (mdhd) atom
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* Ref: https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap2/qtff2.html#//apple_ref/doc/uid/TP40000939-CH204-25615
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*/
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mdhd: async (len: number) => {
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const mdhd_data = await this.tokenizer.readToken<AtomToken.IAtomMdhd>(new AtomToken.MdhdAtom(len));
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// this.parse_mxhd(mdhd_data, this.currentTrack);
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const td = this.getTrackDescription();
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td.creationTime = mdhd_data.creationTime;
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td.modificationTime = mdhd_data.modificationTime;
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td.timeScale = mdhd_data.timeScale;
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td.duration = mdhd_data.duration;
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},
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chap: async (len: number) => {
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const td = this.getTrackDescription();
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const trackIds: number[] = [];
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while (len >= Token.UINT32_BE.len) {
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trackIds.push(await this.tokenizer.readNumber(Token.UINT32_BE));
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len -= Token.UINT32_BE.len;
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}
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td.chapterList = trackIds;
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},
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tkhd: async (len: number) => {
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const track = (await this.tokenizer.readToken<AtomToken.ITrackHeaderAtom>(new AtomToken.TrackHeaderAtom(len))) as ITrackDescription;
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this.tracks.push(track);
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},
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/**
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* Parse mdat atom.
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* Will scan for chapters
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*/
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mdat: async (len: number) => {
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this.audioLengthInBytes = len;
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this.calculateBitRate();
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if (this.options.includeChapters) {
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const trackWithChapters = this.tracks.filter(track => track.chapterList);
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if (trackWithChapters.length === 1) {
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const chapterTrackIds = trackWithChapters[0].chapterList;
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const chapterTracks = this.tracks.filter(track => chapterTrackIds.indexOf(track.trackId) !== -1);
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if (chapterTracks.length === 1) {
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return this.parseChapterTrack(chapterTracks[0], trackWithChapters[0], len);
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}
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}
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}
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await this.tokenizer.ignore(len);
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},
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ftyp: async (len: number) => {
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const types = [];
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while (len > 0) {
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const ftype = await this.tokenizer.readToken<AtomToken.IAtomFtyp>(AtomToken.ftyp);
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len -= AtomToken.ftyp.len;
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const value = ftype.type.replace(/\W/g, '');
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if (value.length > 0) {
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types.push(value); // unshift for backward compatibility
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}
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}
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debug(`ftyp: ${types.join('/')}`);
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const x = types.filter(distinct).join('/');
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this.metadata.setFormat('container', x);
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},
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/**
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* Parse sample description atom
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*/
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stsd: async (len: number) => {
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const stsd = await this.tokenizer.readToken<AtomToken.IAtomStsd>(new AtomToken.StsdAtom(len));
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const trackDescription = this.getTrackDescription();
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trackDescription.soundSampleDescription = stsd.table.map(dfEntry => this.parseSoundSampleDescription(dfEntry));
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},
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/**
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* sample-to-Chunk Atoms
|
|
*/
|
|
stsc: async (len: number) => {
|
|
const stsc = await this.tokenizer.readToken<AtomToken.ITableAtom<AtomToken.ISampleToChunk>>(new AtomToken.StscAtom(len));
|
|
this.getTrackDescription().sampleToChunkTable = stsc.entries;
|
|
},
|
|
|
|
/**
|
|
* time-to-sample table
|
|
*/
|
|
stts: async (len: number) => {
|
|
const stts = await this.tokenizer.readToken<AtomToken.ITableAtom<AtomToken.ITimeToSampleToken>>(new AtomToken.SttsAtom(len));
|
|
this.getTrackDescription().timeToSampleTable = stts.entries;
|
|
},
|
|
|
|
/**
|
|
* Parse sample-sizes atom ('stsz')
|
|
*/
|
|
stsz: async (len: number) => {
|
|
const stsz = await this.tokenizer.readToken<AtomToken.IStszAtom>(new AtomToken.StszAtom(len));
|
|
const td = this.getTrackDescription();
|
|
td.sampleSize = stsz.sampleSize;
|
|
td.sampleSizeTable = stsz.entries;
|
|
},
|
|
|
|
/**
|
|
* Parse chunk-offset atom ('stco')
|
|
*/
|
|
stco: async (len: number) => {
|
|
const stco = await this.tokenizer.readToken<AtomToken.ITableAtom<number>>(new AtomToken.StcoAtom(len));
|
|
this.getTrackDescription().chunkOffsetTable = stco.entries; // remember chunk offsets
|
|
},
|
|
|
|
date: async (len: number) => {
|
|
const date = await this.tokenizer.readToken(new Token.StringType(len, 'utf-8'));
|
|
await this.addTag('date', date);
|
|
}
|
|
};
|
|
|
|
|
|
/**
|
|
* @param sampleDescription
|
|
* Ref: https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html#//apple_ref/doc/uid/TP40000939-CH205-128916
|
|
*/
|
|
private parseSoundSampleDescription(sampleDescription: AtomToken.ISampleDescription): ISoundSampleDescription {
|
|
|
|
const ssd: ISoundSampleDescription = {
|
|
dataFormat: sampleDescription.dataFormat,
|
|
dataReferenceIndex: sampleDescription.dataReferenceIndex
|
|
};
|
|
|
|
let offset = 0;
|
|
if (sampleDescription.description) {
|
|
const version = AtomToken.SoundSampleDescriptionVersion.get(sampleDescription.description, offset);
|
|
offset += AtomToken.SoundSampleDescriptionVersion.len;
|
|
|
|
if (version.version === 0 || version.version === 1) {
|
|
// Sound Sample Description (Version 0)
|
|
ssd.description = AtomToken.SoundSampleDescriptionV0.get(sampleDescription.description, offset);
|
|
} else {
|
|
debug(`Warning: sound-sample-description ${version} not implemented`);
|
|
}
|
|
}
|
|
return ssd;
|
|
}
|
|
|
|
private async parseChapterTrack(chapterTrack: ITrackDescription, track: ITrackDescription, len: number): Promise<void> {
|
|
if (!chapterTrack.sampleSize) {
|
|
if (chapterTrack.chunkOffsetTable.length !== chapterTrack.sampleSizeTable.length)
|
|
throw new Error('Expected equal chunk-offset-table & sample-size-table length.');
|
|
}
|
|
const chapters: IChapter[] = [];
|
|
for (let i = 0; i < chapterTrack.chunkOffsetTable.length && len > 0; ++i) {
|
|
const start = chapterTrack.timeToSampleTable.slice(0, i ).reduce((acc, cur)=> acc + cur.duration, 0);
|
|
|
|
const chunkOffset = chapterTrack.chunkOffsetTable[i];
|
|
const nextChunkLen = chunkOffset - this.tokenizer.position;
|
|
const sampleSize = chapterTrack.sampleSize > 0 ? chapterTrack.sampleSize : chapterTrack.sampleSizeTable[i];
|
|
len -= nextChunkLen + sampleSize;
|
|
if (len < 0) throw new Mp4ContentError('Chapter chunk exceeding token length');
|
|
await this.tokenizer.ignore(nextChunkLen);
|
|
const title = await this.tokenizer.readToken(new AtomToken.ChapterText(sampleSize));
|
|
debug(`Chapter ${i + 1}: ${title}`);
|
|
const chapter = {
|
|
title,
|
|
timeScale: chapterTrack.timeScale,
|
|
start,
|
|
sampleOffset: this.findSampleOffset(track, this.tokenizer.position)
|
|
};
|
|
debug(`Chapter title=${chapter.title}, offset=${chapter.sampleOffset}/${this.tracks[0].duration}`);
|
|
chapters.push(chapter);
|
|
}
|
|
this.metadata.setFormat('chapters', chapters);
|
|
await this.tokenizer.ignore(len);
|
|
}
|
|
|
|
private findSampleOffset(track: ITrackDescription, chapterOffset: number): number {
|
|
|
|
let totalDuration = 0;
|
|
track.timeToSampleTable.forEach(e => {
|
|
totalDuration += e.count * e.duration;
|
|
});
|
|
debug(`Total duration=${totalDuration}`);
|
|
|
|
let chunkIndex = 0;
|
|
while (chunkIndex < track.chunkOffsetTable.length && track.chunkOffsetTable[chunkIndex] < chapterOffset) {
|
|
++chunkIndex;
|
|
}
|
|
|
|
return this.getChunkDuration(chunkIndex + 1, track);
|
|
}
|
|
|
|
private getChunkDuration(chunkId: number, track: ITrackDescription): number {
|
|
let ttsi = 0;
|
|
let ttsc = track.timeToSampleTable[ttsi].count;
|
|
let ttsd = track.timeToSampleTable[ttsi].duration;
|
|
let curChunkId = 1;
|
|
let samplesPerChunk = this.getSamplesPerChunk(curChunkId, track.sampleToChunkTable);
|
|
let totalDuration = 0;
|
|
while (curChunkId < chunkId) {
|
|
const nrOfSamples = Math.min(ttsc, samplesPerChunk);
|
|
totalDuration += nrOfSamples * ttsd;
|
|
ttsc -= nrOfSamples;
|
|
samplesPerChunk -= nrOfSamples;
|
|
if (samplesPerChunk === 0) {
|
|
++curChunkId;
|
|
samplesPerChunk = this.getSamplesPerChunk(curChunkId, track.sampleToChunkTable);
|
|
} else {
|
|
++ttsi;
|
|
ttsc = track.timeToSampleTable[ttsi].count;
|
|
ttsd = track.timeToSampleTable[ttsi].duration;
|
|
}
|
|
}
|
|
return totalDuration;
|
|
}
|
|
|
|
private getSamplesPerChunk(chunkId: number, stcTable: AtomToken.ISampleToChunk[]): number {
|
|
for (let i = 0; i < stcTable.length - 1; ++i) {
|
|
if (chunkId >= stcTable[i].firstChunk && chunkId < stcTable[i + 1].firstChunk) {
|
|
return stcTable[i].samplesPerChunk;
|
|
}
|
|
}
|
|
return stcTable[stcTable.length - 1].samplesPerChunk;
|
|
}
|
|
}
|