Draw audio signal waveform, both in browser or node.

Usage

import Waveform from 'audio-waveform';
import Generator from 'audio-generator';
import Speaker from 'audio-speaker';


//create waveform painter
var plotter = new Waveform({
	//what channel to display, 0 - L, 1 - R
	channel: 0,

	//size of a sliding window to display, number of samples
	size: 1024,

	//offset of a window to display, if undefined - the last piece of data is shown
	offset: undefined,

	//how often to update display (node only)
	framesPerSecond: 20,

	//line or point draw style
	line: true,

	//size of a waveform data to store
	bufferSize: 44100,

	//canvas element to render (optional)
	canvas: undefined

	//...pcm-format options, see pcm-util below
});

var speaker = Speaker();

//place plotter element to the DOM (optionally)
document.body.appendChild(plotter.element);


//send audio-stream to the painter
var stream = new Generator(function (time) {
	return Math.sin(Math.PI * 2 * 440 * time);
});

stream.pipe(speaker);
stream.pipe(plotter);

Related

pcm-util — utils for working with pcm-streams.
audio-render — generic class for implementing any audio-stream rendering.
audio-stat — render any kind of audio info: waveform, spectrogram etc.
boscillate — paint soundwave in terminal for baudio. API is highly inspired by that.
drawille — paint in terminal with braille characters.