Node.js example

[CharlesHolbrow]

Any chance of adding a minimal example for using essentia.js in Node? The main README.md says this is possible, but all the examples are written for the browser.

[jhartquist]

+1 -- I was also looking for a way to include the TS types in a Node project.

[sonoalex]

Here you can find some minimal node examples: Essentia benchmarks . Hope it helps!

[jakiestfu]

I've been having a hard time getting this to run in a node environment.

const url = 'https://site.com/song.mp3'

const buffer = await fetch(url)
  .then((r) => r.arrayBuffer())
  .then(Buffer.from)

const results = await essentia.KeyExtractor(essentia.arrayToVector(buffer))

This yields the wrong key always. What is the recommended approach to providing the expected data to the API, @sonoalex @albincorreya ?

[albincorreya]

@jakiestfu You need to decode the mp3 file buffer into audio data. See some node.js examples with wav files here. You might need to use external libraries to decode mp3 file (eg: https://github.com/audiojs/audio-decode)

[jakiestfu]

Fantastic, @albincorreya Thank you for that reference. Does essentia only support wav containers or are other formats supported as well?

[jakiestfu]

@albincorreya Would you expect for this to be a correct implementation for a remote resource? I'm still getting incorrect keys and scales for MP3 audio.

import decodeAudio from 'audio-decode'
import fetch from 'node-fetch'

const main = async () => {
  const url = 'https://site.com/song.mp3'

  const buffer = await fetch(url).then((r) => r.arrayBuffer())
  const decodedAudio = await decodeAudio(buffer)

  const vector = essentia.arrayToVector(decodedAudio._data)

  const { key, scale, strength } = await essentia.KeyExtractor(vector)
}

main()

[silentrob]

For completion, there are also some examples for Node.js here. https://github.com/MTG/essentia.js-benchmarks/tree/master/node/benchmark

Back to the OP question. I also can't seem to get the KeyExtractor to give me the right key using a WAV or MP3 (node-lame). Based on what some online key detectors say anyway.