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Realtime but not continuous analysis ?

See original GitHub issue

I try to use the nice package for a realtime BPM analysis with line / mic input using navigator.getUserMedia

BPM detection works fine, but I don’t understand why the value is not updated when input BPM changes.

Maybe I made a mistake in my code (or comprehension), but I think the analyzer does not update BPM continiously.

Starting from functionnal example edit app.js :

'use strict';

const RealTimeBPMAnalyzer = require('realtime-bpm-analyzer');

const App = {
  init() {

    var AudioContext = window.AudioContext || window.webkitAudioContext;
	
	navigator.getUserMedia = ( navigator.getUserMedia ||
                       navigator.webkitGetUserMedia ||
                       navigator.mozGetUserMedia ||
                       navigator.msGetUserMedia);
					   
	var context = new AudioContext();
	// Enable mic / line input watching
	navigator.getUserMedia({audio: true}, onStream.bind(this), function() {});

	function onStream(stream) {
		// Set the source with the HTML Audio Node
		var input = context.createMediaStreamSource(stream);
		// Set the scriptProcessorNode to get PCM data in real time
		var scriptProcessorNode = context.createScriptProcessor(4096, 1, 1);

		// Connect everythings together (do not connect input to context.destination to avoid sound looping)
		scriptProcessorNode.connect(context.destination);
		input.connect(scriptProcessorNode);

		var onAudioProcess = new RealTimeBPMAnalyzer({
			scriptNode: {
				bufferSize: 4096,
				numberOfInputChannels: 1,
				numberOfOutputChannels: 1
			},
			pushTime: 2000,
			pushCallback: function(err, bpm) {
				if(bpm && bpm.length)
					console.log('bpm', bpm[0].tempo);   // <= When stabilized, always displays the same BPM
			}
		});

		// Attach realTime function to audioprocess event.inputBuffer (AudioBuffer)
		scriptProcessorNode.onaudioprocess = function (e) {
			onAudioProcess.analyze(e);
		};
	}
	
  }
}

module.exports = App;

Any idea ?