Pipe Web Audio API nodes into PCM Wave files.
$ npm install wave-recorder
var WaveRecorder = require('wave-recorder')
Returns a stream. Pipe the stream to a file (you can use web-fs or something similar).
channels
: (defaults to2
)bitDepth
: can be16
or32
(defaults to32
)silenceDuration
: (optional) Specify the maximum duration (in seconds) of silence to record before pausing. Disabled if0
.
Connect the audio you want to record to this node.
Called on every write with a new header containing an updated file length. You can write this to the start of the file, or ignore (most decoders can handle it, just the duration may appear incorrect).
var WaveRecorder = require('wave-recorder')
var WebFS = require('web-fs')
navigator.webkitPersistentStorage.requestQuota(1024*1024, function(grantedBytes) {
window.webkitRequestFileSystem(PERSISTENT, grantedBytes, onInit)
})
function onInit(fileSystem){
var fs = WebFS(fileSystem.root)
var audioContext = new AudioContext()
navigator.webkitGetUserMedia({audio:true}, function(stream) {
// get the mic input
var audioInput = audioContext.createMediaStreamSource(stream)
// create the recorder instance
var recorder = WaveRecorder(audioContext, {
channels: 2,
bitDepth: 32
})
audioInput.connect(recorder.input)
var filePath = 'test.wav'
var fileStream = fs.createWriteStream(filePath)
recorder.pipe(fileStream)
// optionally go back and rewrite header with updated length
recorder.on('header', function(header){
var headerStream = fs.createWriteStream(path, {
start: 0,
flags: 'r '
})
headerStream.write(header)
headerStream.end()
})
// record for 10 seconds then stop
setTimeout(function(){
recorder.end()
}, 10000)
})
}