https://github.com/naomiaro/webaudio-peaks

Small library to extract peaks from either a TypedArray of audio samples or a webaudio AudioBuffer into an Int8Array, Int16Array, or Int32Array.
https://github.com/naomiaro/webaudio-peaks

peaks waveform webaudio

Last synced: 8 days ago
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Small library to extract peaks from either a TypedArray of audio samples or a webaudio AudioBuffer into an Int8Array, Int16Array, or Int32Array.

• Host: GitHub
• URL: https://github.com/naomiaro/webaudio-peaks
• Owner: naomiaro
• License: mit
• Created: 2016-01-19T00:14:50.000Z (almost 9 years ago)
• Default Branch: main
• Last Pushed: 2023-01-07T09:40:55.000Z (almost 2 years ago)
• Last Synced: 2024-10-16T13:22:23.469Z (24 days ago)
• Topics: peaks, waveform, webaudio
• Language: JavaScript
• Homepage:
• Size: 377 KB
• Stars: 56
• Watchers: 4
• Forks: 10
• Open Issues: 5
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-javascript-audio - webaudio-peaks - small library to get peaks from audio (Libraries: Web Audio API / Web MIDI API)

README

        
# webaudio-peaks

Small library to extract peaks from an array of audio samples or a webaudio AudioBuffer.

[![npm](https://img.shields.io/npm/dm/webaudio-peaks.svg)](https://www.npmjs.com/package/webaudio-peaks)

## Installation

`npm install webaudio-peaks --save`

## Basic Usage

```javascript

var extractPeaks = require("webaudio-peaks");

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();

//decode an ArrayBuffer into an AudioBuffer

audioCtx.decodeAudioData(audioData, function (decodedData) {

  //calculate peaks from an AudioBuffer

  var peaks = extractPeaks(decodedData, 10000, true);

});

```

### extractPeaks(source, samplesPerPixel, isMono, cueIn, cueOut, bits)

function to extract peaks from a TypedArray, or AudioBuffer

**Params**

- source `TypedArray|AudioBuffer` - A source of audio samples.

- samplesPerPixel `number` - Number of samples used to calculate a single peak.

- isMono `boolean` - Combine all channels into one array of peaks or not.

- cueIn `number` - Sample to begin at. The offset is inclusive.

- cueOut `number` - Sample to end at. The offset is exclusive.

- bits `(8|16|32)` - Resolution of calculated peaks.

**Returns**: `object`

```javascript

{

  length: `number`; //Number of calculated peaks,

  //Computed peak data, length ==  #channels or 1 if isMono == true

  //Each entry of type `Int{bits}Array`

  data: `Array`;

  bits: `(8|16|32)`; //Resolution of calculated peaks.

}

```

## License

[MIT License](http://doge.mit-license.org)