jasonpcole/pitch.js

Pitch detection in JavaScript

pitch.js

pitch.js is a pitch detection library written in JavaScript. It is based on the excellent code used in performous. While mainly aimed for human voice, it can also be used with other instruments.

Usage

For pitch.js to work, you'll also need to include fft.js.

pitch.js ships one namespace, called PitchAnalyzer from which all the functionality is available:

/* Create a new pitch detector */
var pitch = new PitchAnalyzer(sampleRate);

/* Copy samples to the internal buffer */
pitch.input(audioBuffer);
/* Process the current input in the internal buffer */
pitch.process();

var tone = pitch.findTone();

if (tone === null) {
	console.log('No tone found!');
} else {
	console.log('Found a tone, frequency:', tone.freq, 'volume:', tone.db);
}

Notes

• The audioBuffer must be mono.
• The internal buffer is 4096 samples long, so if you input more than that without processing in between, you might get incorrect results.

Authors

pitch.js is brought to you by Audiocogs. Please see ./docs/AUTHORS.md for more details.

License

This code is ported from original C++ code by Lasse Kärkkäinen, hence licensed under GPLv2, as is the original. Please see pitch.js/docs/LICENSE.txt for further information.