Awesome
Audio 
Data structure for audio manipulations.
<!-- ideas: - docs - playground: editing based on settings-panel (demo) - gallery: - spectrum vis - waveform vis - demoscene vis - benchmark - recorder app w/ choo - text waveform - player component - downloads - size - image (just teaser/logo) --> <!-- ## Usage [](https://npmjs.org/package/audio/) ```js const Audio = require('audio') ``` -->Use-cases
<!-- ideas: - image file → waveform → processed waveform → file - try yourself - requirebin demo with file opener and processing mvp: - stats: averages, variance - push data - delete data (splice?) - insert data (splice?) - remove Buffer, process from exports --> <!-- ### Load `./sample.mp3`, trim, normalize, fade in, fade out, save: ```js let audio = await new Audio('./sample.mp3') audio .trim() // remove silent head/tail .normalize() // make sure max amplitude is at 1 .fade(.5) // fade in 0.5s at the beginning .fade(-3) // fade out 3s at the end .save('sample-edited.wav') // save as file ``` ### Record 4s of mic input. ```js navigator.getUserMedia({audio: true}, stream => let audio = await new Audio(stream) audio.save('my-record.wav') ) ``` ### Record and download 2 seconds of web-audio experiment ```js //create web-audio experiment let ctx = new AudioContext() let osc = ctx.createOscillator() osc.type = 'sawtooth' osc.frequency.value = 440 osc.start() osc.connect(ctx.destination) //record 2 seconds of web-audio experiment let audio = await Audio.record(osc, 2) audio.save('experiment.wav') osc.stop() ``` ### Download AudioBuffer returned from offline context ```js //setup offline context let offlineCtx = new OfflineAudioContext(2, 44100*40, 44100) audioNode.connect(offlineCtx) //process result of offline context offlineCtx.startRendering().then((audioBuffer) => { Audio(audioBuffer).save() }) ``` ### Montage audio ```js let audio = await Audio('./record.mp3') // repeat slowed down fragment audio.write(audio.slice(2.1, 1).scale(.9), 3.1) // delete fragment, fade out starting from 0.3s for the duration of 2.1s audio.remove(2.4, 2.6).fade(.3, 2.1) // insert other fragment not overwriting the existing data audio.insert(await Audio('./other-record.mp3')) audio.save('edited-record', 'wav') ``` ### Render waveform of HTML5 `<audio>` ```js import Waveform from '@a-vis/waveform' //create waveform renderer let waveform = Waveform(); //get audio element let audio = <audio src="./chopin.mp3"/> //create audio holder audio.on('load', (err, audio) => { let buf = audio.read(4096).getChannelData(0) //put left channel data to waveform renderer waveform.push(data).render() }) ``` ### Process audio with _audio-*_ modules ```js const Biquad = require('audio-biquad') let lpf = new Biquad({frequency: 2000, type: 'lowpass'}) let audio = Audio(10).noise().process(lpf) ``` Data handle - subaudio, for sprites etc Load intro, append 1s pause, start recording. Once ended, save as file. Audio(['./intro.mp3', 1, MediaStream]).once('ready', (err, audio) => audio.save(Date() + '-recording.mp3')) ## [API](https://github.com/audiojs/audio/blob/master/api.md) **1. [Core](#creation)** * [new Audio(src?, opts?)]() * [Audio.from(a, b?, c?, ..., opts?)]() * [Audio.load(url, opts?, cb?)]() * [Audio.decode(buf, opts?, cb?)]() * [audio.buffer]() * [audio.channels]() * [audio.duration]() * [audio.length]() * [audio.sampleRate]() * [audio.time(offset)]() * [audio.offset(time)]() * [Audio.gain(db)]() * [Audio.db(gain)]() * [Audio.isAudio(a)]() * [Audio.isEqual(a, b, ...c)]() * [audio.serialize(format)]() * [audio.save(filename, opts?)]() * [Audio.record(stream, opts?)]() * [audio.stream(dst, opts?, onend?)]() * [audio.clone()]() **2. [Manipulations](#manipulations)** * [audio.read(dst?, t?, dur?, opts?)]() * [audio.write(src|val, t?, dur?, opts?)]() * [audio.insert(data, t?, dur?, opts?)]() * [audio.slice(t?, dur?, opts?)]() * [audio.remove(t?, dur?, opts?)]() * [audio.pad(dur, opts?)]() * [audio.shift(amt, t?, opts?)]() * [audio.trim(opts?)]() * [audio.repeat(times, t?, dur?, opts?)]() * [audio.reverse(t?, dur?, opts?)]() * [audio.invert(t?, dur?, opts?)]() * [audio.gain(db, t?, dur?, opts?)]() * [audio.fade(t?, dur, opts?)]() * [audio.normalize(t?, dur?, opts?)]() * [audio.pan(amt, t?, dur?, opts?)]() * [audio.mix(audio, t?, dur?, opts?)]() * [audio.scale(amt, t?, opts?)]() * [audio.map(fn, opts?)]() **3. [Metrics](#metrics)** * [audio.statistics(t?, dur?, opts?)]() * [audio.bounds(t?, dur?, opts?)]() * [audio.spectrum(t?, dur, opts?)]() * [audio.cepstrum(t?, dur)]() * [audio.loudness(t?, dur)]() * [audio.memory(t?, dur, opts?)]() **4. [Playback](#playback)** * [audio.play(t?, dur?, opts?)]() * [audio.pause()]() * [audio.muted]() * [audio.loop]() * [audio.rate]() * [audio.volume]() * [audio.paused]() <kbd>readonly</kbd> * [audio.currentTime]() ## See Also * [audiojs](https://github.com/audiojs) − open-source audio components for javascript * [web-audio-api](https://github.com/audiojs/web-audio-api) − web-audio-api implementation for nodejs ## Related -->Alternatives
- wad
- tuna
- aural
- pizzicato
- ciseaux
- pjsaudio
- howler
- dsp.js
- audiolet
- dynamicaudio
- audiolib
- bufaudio
- crunker
- sonorous
- waud
- tape.js
License
MIT © <a href="https://github.com/audiojs">audiojs</a>.