totoe
It might be 3 steps
1. ability to get input data
2. processing data
tone.js plugin could get mic data and analyze the amplitude, like official audio does. (step 1, 2)
3. present data, might show by sprites or draw on canvas.
rexrainbow . Yes, thank you seen that. It is completely unnecessary and impractical in it's current state though. Music analysis needs to be down to the second if not millisecond in some cases.
The HTML5 API is already in place, it just needs to be integrated. Not to mention I'm not a fan of relying on a plugin somebody else made. Also, MediaStreamAudioSourceNode Interface: covers microphone input live, also just would need to be integrated. https://dvcs.w3.org/hg/audio/raw-file/t ... SourceNode
Ashley , 
R0J0hound Here are two methods of html5 live audio input:
https://www.html5rocks.com/en/tutorials ... dia/intro/
&
https://developers.google.com/web/updat ... ut-Enabled:
// success callback when requesting audio input stream
function gotStream(stream) {
window.AudioContext = window.AudioContext || window.webkitAudioContext;
var audioContext = new AudioContext();
// Create an AudioNode from the stream.
var mediaStreamSource = audioContext.createMediaStreamSource( stream );
// Connect it to the destination to hear yourself (or any other node for processing!)
mediaStreamSource.connect( audioContext.destination );
}
navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia;
navigator.getUserMedia( {audio:true}, gotStream );