web audio script processing basics

web-audio.js

var master = new webkitAudioContext();

var sineWave = master.createOscillator(); // a default sinewave generator

// this is your js PCM processor node
var scriptNode = master.createScriptProcessor(2048, 1, 1); // chunk size, channels in, channels out

// define this function
scriptNode.onaudioprocess = function(e){
  
  // FYI var chans = e.inputBuffer.numberOfChannels
  
  var output = e.outputBuffer.getChannelData(0); // returns Float32Array(2048)

  var input = e.inputBuffer.getChannelData(0); // same as above
  
  output.set(input) // this would pass the input to the output w/o modification
  
}

sineWave.connect(scriptNode) // connect generator to script node

scriptNode.connect(master.destination); // connect to master out

sineWave.start(0) // start sending the signal to the scriptNode