Difference between revisions of "Stereo Splitting & Panning"

Revision as of 03:46, 23 February 2011

/*

 Stereo Splitting & Panning
 Using the Mozilla Audio Data API
 by F1LT3R @ http://Bocoup.com

• /

// This example is illustrative and not enhanced for performance

// Create a Global pan variable visible to Processing.js Dial Element var pan = 0;

// Define event in global/"window" scope var mozAudioAvailable = function(){};

// When the DOM has loaded... function init(){

 // Variable declarations
 var inputSamples, outputSamples, i, len,
     debug = document.getElementById('debug'),
     output = document.createElement('audio'),
     panElem = document.getElementById('panFormInput');
 
 // Pull the input signal from the mix
 document.getElementById('input').volume = 0;
   
 // Initiate the 
 output.mozSetup(2, 44100, 1);
 
 // WHEN SOUND HAPPENS.........>
 mozAudioAvailable = function mozAudioAvailable(event){
 
   // Alias buffer samples to a more conveinient name
   inputSamples = event.frameBuffer;
       
   // Set new length and clear channel data
   len = inputSamples.length, outputSamples = [];
    
   // Loop thougt the stereo input data...
   for(i=0;i < len; i+=2){
     
     // Copy left channel down via pan value
     outputSamples[i] = inputSamples[i] * (1-pan);
     
     // Copy right channel down via pan value
     outputSamples[i+1] = inputSamples[i+1] * (1- -pan);
   }
  
   // Display 5 samples from each buffer-written-(event at C level)
   debug.innerHTML = "";
   for(i=0;i<5;i++){
     debug.innerHTML += ""+event.time.toFixed(2) + ":  "+ outputSamples[i]+"
";
   }
   
   // Output mixed samples to <audio> element
   output.mozWriteAudio(outputSamples);
  
 };    

 var input = document.getElementById('input');
 //input.volume = 0;
 input.addEventListener("MozAudioAvailable", mozAudioAvailable, false);
     

};

// Call ready event when DOM is loaded addEventListener('DOMContentLoaded', function(){ init(); }, false);