### Processing Audio with VST3 Plugin using vst.js and Web Audio API

Source: https://github.com/ramirezd42/vst-js/blob/master/readme.md

This example demonstrates how to use vst.js to launch a VST3 plugin and process an audio file. It integrates with node-web-audio-api for audio context management and playback, showing the setup of an audio source, script processor, and connection to a speaker, while passing audio blocks through the VST3 plugin for manipulation.

```javascript
const { AudioContext } = require('web-audio-api')
const Speaker = require('speaker')
const fs = require('fs')
const path = require('path')
const vstjs = require('vstjs')

const bufferSize = 512
const numChannels = 2
const pluginPath = process.argv[2]
const filePath = process.argv[3]

const pluginHost = vstjs.launchPlugin(pluginPath)
pluginHost.start()

// setup webaudio stuff
const audioContext = new AudioContext()
const sourceNode = audioContext.createBufferSource()
const scriptNode = audioContext.createScriptProcessor(bufferSize, numChannels, numChannels)


audioContext.outStream = new Speaker({
  channels: audioContext.format.numberOfChannels,
  bitDepth: audioContext.format.bitDepth,
  sampleRate: audioContext.sampleRate,
})

sourceNode.connect(scriptNode)
scriptNode.connect(audioContext.destination)


scriptNode.onaudioprocess = function onaudioprocess(audioProcessingEvent) {
  const inputBuffer = audioProcessingEvent.inputBuffer
  const channels = [...Array(numChannels).keys()]
    .map(i => audioProcessingEvent.inputBuffer.getChannelData(i))

  // process audio block via pluginHost
  pluginHost.processAudioBlock(numChannels, bufferSize, channels)
  audioProcessingEvent.outputBuffer = inputBuffer
}

fs.readFile(filePath, (err, fileBuf) => {
  console.log('reading file..')
  if (err) throw err
  audioContext.decodeAudioData(fileBuf, (audioBuffer) => {
    sourceNode.buffer = audioBuffer
    sourceNode.start(0)
  }, (e) => { throw e })
})
```

--------------------------------

### Installing vst.js via npm

Source: https://github.com/ramirezd42/vst-js/blob/master/readme.md

This snippet provides the npm command to install the vst.js library. This step should only be performed after all other prerequisites, including CMake, Boost, and the Steinberg VST3 SDK, have been successfully installed and configured.

```bash
npm install vstjs
```

--------------------------------

### Installing CMake via Homebrew (macOS)

Source: https://github.com/ramirezd42/vst-js/blob/master/readme.md

This snippet provides the command to install CMake, a required build system for vst.js, using Homebrew on macOS. CMake must be present on the system before attempting to install vst.js.

```bash
brew install cmake
```

--------------------------------

### Installing Boost C++ Framework via Homebrew (macOS)

Source: https://github.com/ramirezd42/vst-js/blob/master/readme.md

This snippet shows how to install the Boost C++ Framework (version 3.6 or higher) using Homebrew on macOS. Boost is a popular C++ library that vst.js depends on and must be available prior to installation.

```bash
brew install boost
```

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