Noise Voice

WebRTC based video chat with a possibility to modify your voice with special effects (Web Audio Api)

##How it works in a nutshell The video and audio is received from the user using getUserMedia().

The voice is modified using Web Audio Api. A great place to start with audio api is this tutorial.

To make modifying of the voice somewhat easier I used a tuna.js audio effects library, which is great and very easy to use with the only downside that it does not support Firefox. But anyway building these audio effects from scratch would be a nighmare.

To be able to connect/disconnect and adjust properties of Audio Nodes I wrote a small audio-controls.js library, which works with native audio nodes and also with tuna.js audio effects nodes.

The video and audio are that exchanged between users using WebRTC. Node.js is used as a signalling server. The biggest part of the WebRTC and socket.io set up is based on this great tutorial.

I also used express.js for the basic app set up.

##How to use audio-controls.js library

1.Create audio context and add fallbacks for outdated Web Audio syntax

//defining audio context
context = new (window.AudioContext || window.webkitAudioContext)();
//fallbacks for Web Audio syntax
if (!context.createGain) {
	context.createGain = context.createGainNode;
}
if (!context.createGainNode) {
	context.createGainNode = context.createGain;
}
if (!context.createDelay)	{
  context.createDelay = context.createDelayNode;
}
if (!context.createDelayNode) {
	context.createDelayNode = context.createDelay;
}
if (!context.createScriptProcessor)	{
  context.createScriptProcessor = context.createJavaScriptNode;
}
if (!context.createJavaScriptNode)	{
  context.createJavaScriptNode= context.createScriptProcessor;
}

2.Load tuna.js library before audio-controls.js

3.Load audio-controls.js and initializing it:

//specify which nodes you want to use in the square brackets
audioNodes = new AudioNodes ( stream, [ "delay", "tunachorus", "tunawahwah", "tunaoverdrive",  "tunatremolo", "streamDestination"] );

###Methods Turn an audio node on or off AudioNodes.prototype.nodeSwitch(audioNodeObject);