Add voice notes

// FREEBIE

components/recorderjs/recorder.js

@@ -0,0 +1,97 @@
+(function(window){
+
+  var WORKER_PATH = 'recorderWorker.js';
+
+  var Recorder = function(source, cfg){
+    var config = cfg || {};
+    var bufferLen = config.bufferLen || 4096;
+    this.context = source.context;
+    this.node = (this.context.createScriptProcessor ||
+                 this.context.createJavaScriptNode).call(this.context,
+                                                         bufferLen, 2, 2);
+    var worker = new Worker(config.workerPath || WORKER_PATH);
+    worker.postMessage({
+      command: 'init',
+      config: {
+        sampleRate: this.context.sampleRate
+      }
+    });
+    var recording = false,
+      currCallback;
+
+    var self = this;
+    this.node.onaudioprocess = function(e){
+      if (!recording) return;
+      self.ondata && self.ondata(e.inputBuffer.getChannelData(0));
+      worker.postMessage({
+        command: 'record',
+        buffer: [
+          e.inputBuffer.getChannelData(0),
+          e.inputBuffer.getChannelData(1)
+        ]
+      });
+    }
+
+    this.configure = function(cfg){
+      for (var prop in cfg){
+        if (cfg.hasOwnProperty(prop)){
+          config[prop] = cfg[prop];
+        }
+      }
+    }
+
+    this.record = function(){
+      recording = true;
+    }
+
+    this.stop = function(){
+      recording = false;
+    }
+
+    this.clear = function(){
+      worker.postMessage({ command: 'clear' });
+    }
+
+    this.getBuffer = function(cb) {
+      currCallback = cb || config.callback;
+      worker.postMessage({ command: 'getBuffer' })
+    }
+
+    this.exportWAV = function(cb, type){
+      currCallback = cb || config.callback;
+      type = type || config.type || 'audio/wav';
+      if (!currCallback) throw new Error('Callback not set');
+      worker.postMessage({
+        command: 'exportWAV',
+        type: type
+      });
+    }
+
+    this.shutdown = function(){
+      worker.terminate();
+      source.disconnect();
+      this.node.disconnect();
+    };
+
+    worker.onmessage = function(e){
+      var blob = e.data;
+      currCallback(blob);
+    }
+
+    source.connect(this.node);
+    this.node.connect(this.context.destination);    //this should not be necessary
+  };
+
+  Recorder.forceDownload = function(blob, filename){
+    var url = (window.URL || window.webkitURL).createObjectURL(blob);
+    var link = window.document.createElement('a');
+    link.href = url;
+    link.download = filename || 'output.wav';
+    var click = document.createEvent("Event");
+    click.initEvent("click", true, true);
+    link.dispatchEvent(click);
+  }
+
+  window.Recorder = Recorder;
+
+})(window);