Add voice notes

// FREEBIE

components/webaudiorecorder/lib/WebAudioRecorder.js

@@ -0,0 +1,199 @@
+(function(window) {
+  // internal: same as jQuery.extend(true, args...)
+  var extend = function() {
+    var target = arguments[0],
+        sources = [].slice.call(arguments, 1);
+    for (var i = 0; i < sources.length; ++i) {
+      var src = sources[i];
+      for (key in src) {
+        var val = src[key];
+        target[key] = typeof val === "object"
+          ? extend(typeof target[key] === "object" ? target[key] : {}, val)
+          : val;
+      }
+    }
+    return target;
+  };
+
+  var WORKER_FILE = {
+    wav: "WebAudioRecorderWav.js",
+    ogg: "WebAudioRecorderOgg.js",
+    mp3: "WebAudioRecorderMp3.js"
+  };
+
+  // default configs
+  var CONFIGS = {
+    workerDir: "/",     // worker scripts dir (end with /)
+    numChannels: 2,     // number of channels
+    encoding: "wav",    // encoding (can be changed at runtime)
+
+    // runtime options
+    options: {
+      timeLimit: 300,           // recording time limit (sec)
+      encodeAfterRecord: false, // process encoding after recording
+      progressInterval: 1000,   // encoding progress report interval (millisec)
+      bufferSize: undefined,    // buffer size (use browser default)
+
+      // encoding-specific options
+      wav: {
+        mimeType: "audio/wav"
+      },
+      ogg: {
+        mimeType: "audio/ogg",
+        quality: 0.5            // (VBR only): quality = [-0.1 .. 1]
+      },
+      mp3: {
+        mimeType: "audio/mpeg",
+        bitRate: 160            // (CBR only): bit rate = [64 .. 320]
+      }
+    }
+  };
+
+  // constructor
+  var WebAudioRecorder = function(sourceNode, configs) {
+    extend(this, CONFIGS, configs || {});
+    this.context = sourceNode.context;
+    if (this.context.createScriptProcessor == null)
+      this.context.createScriptProcessor = this.context.createJavaScriptNode;
+    this.input = this.context.createGain();
+    sourceNode.connect(this.input);
+    this.buffer = [];
+    this.initWorker();
+  };
+
+  // instance methods
+  extend(WebAudioRecorder.prototype, {
+    isRecording: function() { return this.processor != null; },
+
+    setEncoding: function(encoding) {
+      if (this.isRecording())
+        this.error("setEncoding: cannot set encoding during recording");
+      else if (this.encoding !== encoding) {
+        this.encoding = encoding;
+        this.initWorker();
+      }
+    },
+
+    setOptions: function(options) {
+      if (this.isRecording())
+        this.error("setOptions: cannot set options during recording");
+      else {
+        extend(this.options, options);
+        this.worker.postMessage({ command: "options", options: this.options });
+      }
+    },
+
+    startRecording: function() {
+      if (this.isRecording())
+        this.error("startRecording: previous recording is running");
+      else {
+        var numChannels = this.numChannels,
+            buffer = this.buffer,
+            worker = this.worker;
+        this.processor = this.context.createScriptProcessor(
+                                this.options.bufferSize,
+                                this.numChannels, this.numChannels);
+        this.input.connect(this.processor);
+        this.processor.connect(this.context.destination);
+        this.processor.onaudioprocess = function(event) {
+          for (var ch = 0; ch < numChannels; ++ch)
+            buffer[ch] = event.inputBuffer.getChannelData(ch);
+          worker.postMessage({ command: "record", buffer: buffer });
+        };
+        this.worker.postMessage({
+          command: "start",
+          bufferSize: this.processor.bufferSize
+        });
+        this.startTime = Date.now();
+      }
+    },
+
+    recordingTime: function() {
+      return this.isRecording() ? (Date.now() - this.startTime) * 0.001 : null;
+    },
+
+    cancelRecording: function() {
+      if (this.isRecording()) {
+        this.input.disconnect();
+        this.processor.disconnect();
+        delete this.processor;
+        this.worker.postMessage({ command: "cancel" });
+      } else
+        this.error("cancelRecording: no recording is running");
+    },
+
+    finishRecording: function() {
+      if (this.isRecording()) {
+        this.input.disconnect();
+        this.processor.disconnect();
+        delete this.processor;
+        this.worker.postMessage({ command: "finish" });
+      } else
+        this.error("finishRecording: no recording is running");
+    },
+
+    cancelEncoding: function() {
+      if (this.options.encodeAfterRecord)
+        if (this.isRecording())
+          this.error("cancelEncoding: recording is not finished");
+        else {
+          this.onEncodingCanceled(this);
+          this.initWorker();
+        }
+      else
+        this.error("cancelEncoding: invalid method call");
+    },
+
+    initWorker: function() {
+      if (this.worker != null)
+        this.worker.terminate();
+      this.onEncoderLoading(this, this.encoding);
+      this.worker = new Worker(this.workerDir + WORKER_FILE[this.encoding]);
+      var _this = this;
+      this.worker.onmessage = function(event) {
+        var data = event.data;
+        switch (data.command) {
+          case "loaded":
+            _this.onEncoderLoaded(_this, _this.encoding);
+            break;
+          case "timeout":
+            _this.onTimeout(_this);
+            break;
+          case "progress":
+            _this.onEncodingProgress(_this, data.progress);
+            break;
+          case "complete":
+            _this.onComplete(_this, data.blob);
+            break;
+          case "error":
+            _this.error(data.message);
+        }
+      };
+      this.worker.postMessage({
+        command: "init",
+        config: {
+          sampleRate: this.context.sampleRate,
+          numChannels: this.numChannels
+        },
+        options: this.options
+      });
+    },
+
+    error: function(message) {
+      this.onError(this, "WebAudioRecorder.js:" + message);
+    },
+
+    // event handlers
+    onEncoderLoading: function(recorder, encoding) {},
+    onEncoderLoaded: function(recorder, encoding) {},
+    onTimeout: function(recorder) { recorder.finishRecording(); },
+    onEncodingProgress: function (recorder, progress) {},
+    onEncodingCanceled: function(recorder) {},
+    onComplete: function(recorder, blob) {
+      recorder.onError(recorder, "WebAudioRecorder.js: You must override .onComplete event");
+    },
+    onError: function(recorder, message) { console.log(message); }
+  });
+
+  window.WebAudioRecorder = WebAudioRecorder;
+})(window);

components/webaudiorecorder/lib/WebAudioRecorderMp3.js

@@ -0,0 +1,91 @@
+importScripts("Mp3LameEncoder.min.js");
+
+var NUM_CH = 2, // constant
+    sampleRate = 44100,
+    options = undefined,
+    maxBuffers = undefined,
+    encoder = undefined,
+    recBuffers = undefined,
+    bufferCount = 0;
+
+function error(message) {
+  self.postMessage({ command: "error", message: "mp3: " + message });
+}
+
+function init(data) {
+  if (data.config.numChannels === NUM_CH) {
+    sampleRate = data.config.sampleRate;
+    options = data.options;
+  } else
+    error("numChannels must be " + NUM_CH);
+};
+
+function setOptions(opt) {
+  if (encoder || recBuffers)
+    error("cannot set options during recording");
+  else
+    options = opt;
+}
+
+function start(bufferSize) {
+  maxBuffers = Math.ceil(options.timeLimit * sampleRate / bufferSize);
+  if (options.encodeAfterRecord)
+    recBuffers = [];
+  else
+    encoder = new Mp3LameEncoder(sampleRate, options.mp3.bitRate);
+}
+
+function record(buffer) {
+  if (bufferCount++ < maxBuffers)
+    if (encoder)
+      encoder.encode(buffer);
+    else
+      recBuffers.push(buffer);
+  else
+    self.postMessage({ command: "timeout" });
+};
+
+function postProgress(progress) {
+  self.postMessage({ command: "progress", progress: progress });
+};
+
+function finish() {
+  if (recBuffers) {
+    postProgress(0);
+    encoder = new Mp3LameEncoder(sampleRate, options.mp3.bitRate);
+    var timeout = Date.now() + options.progressInterval;
+    while (recBuffers.length > 0) {
+      encoder.encode(recBuffers.shift());
+      var now = Date.now();
+      if (now > timeout) {
+        postProgress((bufferCount - recBuffers.length) / bufferCount);
+        timeout = now + options.progressInterval;
+      }
+    }
+    postProgress(1);
+  }
+  self.postMessage({
+    command: "complete",
+    blob: encoder.finish(options.mp3.mimeType)
+  });
+  cleanup();
+};
+
+function cleanup() {
+  encoder = recBuffers = undefined;
+  bufferCount = 0;
+}
+
+self.onmessage = function(event) {
+  var data = event.data;
+  switch (data.command) {
+    case "init":    init(data);                 break;
+    case "options": setOptions(data.options);   break;
+    case "start":   start(data.bufferSize);     break;
+    case "record":  record(data.buffer);        break;
+    case "finish":  finish();                   break;
+    case "cancel":  cleanup();
+  }
+};
+
+self.postMessage({ command: "loaded" });