node-record-lpcm16

    1.0.1 • Public • Published

    node-record-lpcm-16

    Records a 16-bit signed-integer linear pulse modulation code WAV audio file.

    This module uses Node.js streams to minimize memory usage and optimize speed, perfect for embedded devices and "the internet of things".

    These audio files are fully compatible with both the Google Speech to Text API (v2) and the Wit.ai Speech API.

    Installation

    npm install node-record-lpcm16

    Dependencies

    Generally, running npm install should suffice.

    This module requires you to install SoX and it must be available in your $PATH.

    For Mac OS

    brew install sox

    For most linux disto's

    sudo apt-get install sox libsox-fmt-all

    For Windows

    download the binaries

    Options

    sampleRate            : 16000  // audio sample rate
    channels              : 1      // number of channels
    threshold             : 0.5    // silence threshold (rec only)
    endOnSilence          : false  // automatically end on silence (if supported)
    thresholdStart        : null   // silence threshold to start recording, overrides threshold (rec only)
    thresholdEnd          : null   // silence threshold to end recording, overrides threshold (rec only)
    silence               : '1.0'  // seconds of silence before ending
    recorder              : 'sox'  // Defaults to 'sox'
    device                : null   // recording device (e.g.: 'plughw:1')
    audioType             : 'wav'  // audio type to record
    

    Please note that arecord might not work on all operating systems. If you can't capture any sound with arecord, try to change device (arecord -l).

    Usage

    const recorder = require('node-record-lpcm16')
    const fs = require('fs')
     
    const file = fs.createWriteStream('test.wav', { encoding: 'binary' })
     
    recorder.record({
      sampleRate: 44100
    })
    .stream()
    .pipe(file)

    You can pause, resume and stop the recording manually.

    const recorder = require('node-record-lpcm16')
    const fs = require('fs')
     
    const file = fs.createWriteStream('test.wav', { encoding: 'binary' })
     
    const recording = recorder.record()
    recording.stream().pipe(file)
     
    // Pause recording after one second
    setTimeout(() => {
      recording.pause()
    }, 1000)
     
    // Resume another second later
    setTimeout(() => {
      recording.resume()
    }, 2000)
     
    // Stop recording after three seconds
    setTimeout(() => {
      recording.stop()
    }, 3000)

    Recorders

    The following recorders are included:

    • rec
    • sox
    • arecord

    Note: not all recorders support all features!

    Error handling

    Some recorders might be logging errors to stderr and throw an exit code. You can catch early termination by adding an error event listener to the stream.

    To debug the recorder see debugging below.

    recording.stream()
      .on('error', err => {
        console.error('recorder threw an error:', err)
      })
      .pipe(file)

    Debugging

    Debug logging is implemented with visionmedia/debug

    DEBUG=record node examples/file.js

    Example

    Here's how you can write your own Siri in just 10 lines of code.

    const recorder = require('../')
    const request = require('request')
     
    const witToken = process.env.WIT_TOKEN // get one from wit.ai!
     
    function parseResult (err, resp, body) {
      if (err) console.error(err)
      console.log(body)
    }
     
    const recording = recorder.record({
      recorder: 'arecord'
    })
     
    recording
      .stream()
      .pipe(request.post({
        'url': 'https://api.wit.ai/speech?client=chromium&lang=en-us&output=json',
        'headers': {
          'Accept': 'application/vnd.wit.20160202+json',
          'Authorization': `Bearer ${witToken}`,
          'Content-Type': 'audio/wav'
        }
      }, parseResult))
     
    setTimeout(() => {
      recording.stop()
    }, 3000) // Stop after three seconds of recording

    Install

    npm i node-record-lpcm16

    DownloadsWeekly Downloads

    657

    Version

    1.0.1

    License

    ISC

    Unpacked Size

    12.4 kB

    Total Files

    14

    Last publish

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