https://github.com/scijs/fourier-transform

Minimalistic and efficient FFT implementation
https://github.com/scijs/fourier-transform

Last synced: 5 days ago
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Minimalistic and efficient FFT implementation

• Host: GitHub
• URL: https://github.com/scijs/fourier-transform
• Owner: scijs
• Created: 2016-05-13T16:06:02.000Z (about 8 years ago)
• Default Branch: master
• Last Pushed: 2021-06-21T22:46:49.000Z (about 3 years ago)
• Last Synced: 2024-06-18T15:22:11.734Z (19 days ago)
• Language: JavaScript
• Homepage:
• Size: 55.7 KB
• Stars: 166
• Watchers: 7
• Forks: 19
• Open Issues: 2
• Metadata Files:
  • Readme: readme.md

Lists

• awesome-nodejs-pure-js - fourier-transform

README

        
# fourier-transform [![stable](https://img.shields.io/badge/stability-stable-brightgreen.svg)](http://github.com/badges/stability-badges) [![Build Status](https://img.shields.io/travis/scijs/fourier-transform.svg)](https://travis-ci.org/scijs/fourier-transform)

Minimalistic and efficient FFT implementation for 2n-size inputs. Includes regular and asm.js versions.

[![npm install fourier-transform](https://nodei.co/npm/fourier-transform.png?mini=true)](https://npmjs.org/package/fourier-transform/)

```js

var ft = require('fourier-transform')

var db = require('decibels')

var sine = require('audio-oscillator/sin')

// generate sine wave 440 Hz

var waveform = sine(1024, 440)

//get normalized magnitudes for frequencies from 0 to 22050 with interval 44100/1024 ≈ 43Hz

var spectrum = ft(waveform)

//convert to decibels

var decibels = spectrum.map((value) => db.fromGain(value))

```

To use asm.js version, require as `require('fourier-transform/asm')`. That is ~35% faster.

## Thanks

To all the [existing fft packages](./benchmark.md), without them this one would not be possible. Special thanks to @corbanbrook for the most efficient implementation in [dsp.js](https://github.com/corbanbrook/dsp.js). This package is based on [dsp.js RFFT](https://github.com/corbanbrook/dsp.js/blob/master/dsp.js#L554), which is based on [RealFFT](http://www.jjj.de/fxt/).

## Contribute

If you find it slow, difficult or broken, please [post an issue](https://github.com/dfcreative/fourier-transform/issues). If you have ideas or know-hows for better implementation - [PR’s are welcome](https://github.com/dfcreative/fourier-transform/pulls).

## Related

* [fourier transforms benchmark](./benchmark.md).

* [ndarray-fft](https://github.com/scijs/ndarray-fft) FFT for ndarrays, allowing not-power-of-two inputs.

* [gl-fourier](https://github.com/dfcreative/gl-fourier) WebGL fourier transform implementations.

* [gl-spectrum](https://github.com/dfcreative/gl-spectrum) render spectrum in 2d/3d canvas.