audio-type

Detect the audio type of a ArrayBuffer/Uint8Array

Install

$ npm i audio-type

Usage

Node.js

import readChunk from 'read-chunk'; // npm install read-chunk
import audioType from 'audio-type';
var buffer = readChunk.sync('meow.wav', 0, 64);

audioType(buffer);
//=> wav

Browser

import audioType from './audio-type.js'

var xhr = new XMLHttpRequest();
xhr.open('GET', 'meow.flac');
xhr.responseType = 'arraybuffer';

xhr.onload = function () {
	audioType(this.response);
	//=> flac
};

xhr.send();

API

audioType(buffer)

Returns one of the keys below, or undefined if the format isn't recognized.

| Key | Format | Magic | Offset | | --- | --- | --- | --- | | wav | WAVE | RIFF…WAVE | 0, 8 | | aiff | AIFF/AIFC | FORM…AIFF/AIFC | 0, 8 | | mp3 | MPEG audio | MPEG sync (0xFF Ex) or TAG (ID3v1 trailer) | 0 | | aac | AAC (ADTS) | 0xFFF sync, layer 00 | 0 | | flac | FLAC, native or in Ogg | fLaC, or OggS…\x7FFLAC | 0, or 0 and 28 | | tta | True Audio | TTA1 | 0 | | m4a | MPEG-4 audio | ftyp or M4A | 4 or 0 | | opus | Opus (in Ogg) | OggS…OpusHead | 0, 28 | | oga | Ogg | OggS | 0 | | qoa | Quite OK Audio | qoaf | 0 | | mid | MIDI | MThd | 0 | | caf | Core Audio Format | caff | 0 | | wma | ASF/WMA | ASF header GUID | 0 | | amr | AMR | #!AMR | 0 | | wv | WavPack | wvpk | 0 | | mpc | Musepack | MP+ (SV7) or MPCK (SV8) | 0 | | ape | Monkey's Audio | MAC | 0 | | dsf | DSD Stream File | DSD | 0 | | dff | DSDIFF | FRM8…DSD | 0, 12 | | eac3 | E-AC-3 (Dolby Digital Plus) | 0x0B77 sync, bsid 11–16 | 0 | | ac3 | AC-3 (Dolby Digital) | 0x0B77 sync, bsid ≤ 8 | 0 | | dts | DTS | 0x7FFE8001 (or its bit-reordered variants) | 0 | | it | Impulse Tracker | IMPM | 0 | | s3m | Scream Tracker 3 | SCRM | 44 | | xm | Extended Module | Extended Module: | 0 | | mod | ProTracker & friends | M.K., M!K!, xCHN, xxCH, FLTx, TDZx, CD81, OKTA | 1080 | | mkv | Matroska | EBML header, DocType matroska | 0 | | webm | WebM | EBML header, DocType webm | 0 | | avi | AVI | RIFF…AVI | 0, 8 |

Note: OpenMPT's .mptm format is IT-derived and reuses the IMPM magic verbatim — it is indistinguishable from .it by magic bytes alone and also detects as it.

buffer

Type: buffer (Node.js), arrayBuffer, uint8array

The first 64 bytes are enough for every format except mod, whose tag sits at offset 1080 (past the sample header table) — pass at least the first 1084 bytes if you need to detect trackers.

ID3v2 tags

mp3, flac, tta and aac files may carry a leading ID3v2 tag. audioType() skips it and inspects what follows: mp3 is only returned once a real MPEG sync is found after the tag — unless the tag's declared size runs past the end of the buffer you gave it, in which case mp3 is assumed (the overwhelming majority of ID3v2-tagged audio in the wild is MP3, and a truncated probe buffer — the common case — can't prove otherwise). dsf's optional ID3v2 tag lives at the end of the file, not the start, so it never enters into this.

License

MIT • ॐ