music-metadata

Stream and file based music metadata parser for node.

Features

Support for audio file types

Audio format	Description	Wiki
AIFF / AIFF-C	Audio Interchange File Format	🔗
AAC	ADTS / Advanced Audio Coding	🔗
APE	Monkey's Audio	🔗
ASF	Advanced Systems Format	🔗
DSDIFF	Philips DSDIFF	🔗
DSF	Sony's DSD Stream File	🔗
FLAC	Free Lossless Audio Codec	🔗
MP2	MPEG-1 Audio Layer II	🔗
MP3	MPEG-1 / MPEG-2 Audio Layer III	🔗
MPC	Musepack SV7	🔗
MPEG 4	mp4, m4a, m4v	🔗
Ogg / Opus		🔗
Ogg / Speex		🔗
Ogg / Vorbis		🔗
WAV		🔗
WV	WavPack	🔗
WMA	Windows Media Audio	🔗

Supported tag headers

Following tag header formats are supported:

• APE
• ASF
• EXIF 2.3
• ID3: ID3v1, ID3v1.1, ID3v2.2, ID3v2.3 & ID3v2.4
• iTunes
• RIFF/INFO
• Vorbis comment

Support for MusicBrainz tags as written by Picard.

Audio format & encoding details

Support for encoding / format details:

• Bit rate
• Audio bit depth
• Duration
• Encoding profile (e.g. CBR, V0, V2)

Online demo's

• Audio Tag Analyzer
• Webamp

Compatibility

The JavaScript in runtime is compliant with ECMAScript 2017 (ES8). Requires Node.js® version 6 or higher.

Browser Support

Although music-metadata is designed to run in Node.js, it can also be used to run in the browser:

• music-metadata-browser is better suitable to run in the browser.

To avoid Node fs dependency inclusion, you may use a sub-module inclusion:

import * as mm from 'music-metadata/lib/core';

function	music-metadata	music-metadata/lib/core
parseBuffer	✓	✓
parseStream *	✓	✓
parseFromTokenizer	✓	✓
parseFile	✓

Donation

Not required, but would be extremely motivating. PayPal.me

Usage

Installation

Install via npm:

npm install music-metadata

or yarn

yarn add music-metadata

Import music-metadata

Import music-metadata in JavaScript:

const mm = require('music-metadata');

This is how it's done in TypeScript:

import * as mm from 'music-metadata';

Module Functions

There are two ways to parse (read) audio tracks:

1. Audio (music) files can be parsed using direct file access using the parseFile function
2. Using Node.js streams using the parseStream function.

Direct file access tends to be a little faster, because it can 'jump' to various parts in the file without being obliged to read intermediate date.

parseFile function

Parses the specified file (filePath) and returns a promise with the metadata result (IAudioMetadata).

parseFile(filePath: string, opts: IOptions = {}): Promise<IAudioMetadata>`

Javascript example:

const mm = require('music-metadata');
const util = require('util')

mm.parseFile('../test/samples/MusicBrainz-multiartist [id3v2.4].V2.mp3', {native: true})
  .then( metadata => {
    console.log(util.inspect(metadata, { showHidden: false, depth: null }));
  })
  .catch( err => {
    console.error(err.message);
  });

Typescript example:

import * as mm from 'music-metadata';
import * as util from 'util';

mm.parseFile('../test/samples/MusicBrainz-multiartist [id3v2.4].V2.mp3')
  .then( metadata => {
    console.log(util.inspect(metadata, {showHidden: false, depth: null}));
  })
  .catch((err) => {
    console.error(err.message);
  });

parseStream function

Parses the provided audio stream for metadata. It is recommended to provide the corresponding MIME-type. An extension (e.g.: .mp3), filename or path will also work. If the MIME-type or filename is not provided, or not understood, music-metadata will try to derive the type from the content.

parseStream(stream: Stream.Readable, mimeType?: string, opts?: IOptions = {}): Promise<IAudioMetadata>`

Example:

mm.parseStream(someReadStream, 'audio/mpeg', { fileSize: 26838 })
  .then( metadata => {
     console.log(util.inspect(metadata, { showHidden: false, depth: null }));
     someReadStream.destroy();
   });

parseBuffer function

Parses content of the provided buffer for metadata.

parseBuffer(buffer: Buffer, mimeType?: string, opts?: IOptions = {}): Promise<IAudioMetadata>

Example:

mm.parseBuffer(someBuffer, 'audio/mpeg', { fileSize: 26838 })
  .then( metadata => {
    console.log(util.inspect(metadata, { showHidden: false, depth: null }));
   });

orderTags function

Utility to Converts the native tags to a dictionary index on the tag identifier

orderTags(nativeTags: ITag[]): [tagId: string]: any[]

ratingToStars function

Can be used to convert the normalized rating value to the 0..5 stars, where 0 an undefined rating, 1 the star the lowest rating and 5 the highest rating.

ratingToStars(rating: number): number

Options

• duration: default: false, if set to true, it will parse the whole media file if required to determine the duration.
• fileSize: only provide this in combination with parseStream function.
• native: default: false, if set to true, it will return native tags in addition to the common tags.
• observer: (update: MetadataEvent) => void;: Will be called after each change to common (generic) tag, or format properties.
• skipCovers: default: false, if set to true, it will not return embedded cover-art (images).
• skipPostHeaders? boolean default: false, if set to true, it will not search all the entire track for additional headers. Only recommenced to use in combination with streams.

Although in most cases duration is included, in some cases it requires music-metadata parsing the entire file. To enforce parsing the entire file if needed you should set duration to true.

Metadata result

If the returned promise resolves, the metadata (TypeScript IAudioMetadata interface) contains:

• format: IFormat Audio format information
• native: INativeTags List of native (original) tags found in the parsed audio file. If the native option is set to false, this property is not defined.
• common: ICommonTagsResult Is a generic (abstract) way of reading metadata information.

Format

Audio format information. Defined in the TypeScript IFormat interface:

• container?: string Audio encoding format. e.g.: 'flac'
• codec? Name of the codec (algorithm used for the audio compression)
• codecProfile?: string Codec profile / settings
• tagTypes?: TagType[] List of tagging formats found in parsed audio file
• duration?: number Duration in seconds
• bitrate?: number Number bits per second of encoded audio file
• sampleRate?: number Sampling rate in Samples per second (S/s)
• bitsPerSample?: number Audio bit depth
• lossless?: boolean True if lossless, false for lossy encoding
• numberOfChannels?: number Number of audio channels
• numberOfSamples?: number Number of samples frames, one sample contains all channels. The duration is: numberOfSamples / sampleRate

Common

Common tag documentation is automatically generated.

Examples

In order to read the duration of a stream (with the exception of file streams), in some cases you should pass the size of the file in bytes.

mm.parseStream(someReadStream, 'audio/mpeg', { duration: true, fileSize: 26838 })
  .then( function (metadata) {
     console.log(util.inspect(metadata, { showHidden: false, depth: null }));
     someReadStream.close();
   });

Frequently Asked Questions

1. How can I traverse (a long) list of files?

   What is important that file parsing should be done in a sequential manner. In a plain loop, due to the asynchronous character (like most JavaScript functions), it would cause all the files to run in parallel which is will cause your application to hang in no time. There are multiple ways of achieving this:

   1. Using recursion

      const mm = require('music-metadata')
      
      function parseFiles(audioFiles) {
        
        const audioFile = audioFiles.shift();
        
        if (audioFile) {
          return mm.parseFile(audioFile).then(metadata => {
            // Do great things with the metadata
            return parseFiles(audioFiles); // process rest of the files AFTER we are finished
          })
        }
        
        return Promise.resolve();
      }

   2. Use async/await

      Use async/await

      const mm = require('music-metadata')
      
      // it is required to declare the function 'async' to allow the use of await
      async function parseFiles(audioFiles) {
      
          for (const audioFile of audioFiles) {
          
              // await will ensure the metadata parsing is completed before we move on to the next file
              const metadata = await mm.parseFile(audioFile);
              // Do great things with the metadata
          }
      }

   3. Use a specialized module to traverse files

      There are specialized modules to traversing (walking) files and directory, like walk.

Licence

(The MIT License)

Copyright (c) 2017 Borewit

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.