src/chrome/browser/resources/app_list/speech_manager.js

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * @fileoverview The class to Manage both offline / online speech recognition.
   7  */
   8
   9 <include src="plugin_manager.js"/>
  10 <include src="audio_manager.js"/>
  11 <include src="speech_recognition_manager.js"/>
  12
  13 cr.define('speech', function() {
  14   'use strict';
  15
  16   /**
  17    * The state of speech recognition.
  18    *
  19    * @enum {string}
  20    */
  21   var SpeechState = {
  22     READY: 'READY',
  23     HOTWORD_RECOGNIZING: 'HOTWORD_RECOGNIZING',
  24     RECOGNIZING: 'RECOGNIZING',
  25     STOPPING: 'STOPPING'
  26   };
  27
  28   /**
  29    * @constructor
  30    */
  31   function SpeechManager() {
  32     this.audioManager_ = new speech.AudioManager();
  33     this.audioManager_.addEventListener('audio', this.onAudioLevel_.bind(this));
  34     if (speech.isPluginAvailable()) {
  35       var pluginManager = new speech.PluginManager(
  36           this.onHotwordRecognizerReady_.bind(this),
  37           this.onHotwordRecognized_.bind(this));
  38       pluginManager.scheduleInitialize(
  39           this.audioManager_.getSampleRate(),
  40           'chrome://app-list/okgoogle_hotword.config');
  41     }
  42     this.speechRecognitionManager_ = new speech.SpeechRecognitionManager(this);
  43     this.setState_(SpeechState.READY);
  44   }
  45
  46   /**
  47    * Updates the state.
  48    *
  49    * @param {SpeechState} newState The new state.
  50    * @private
  51    */
  52   SpeechManager.prototype.setState_ = function(newState) {
  53     this.state = newState;
  54   };
  55
  56   /**
  57    * Called with the mean audio level when audio data arrives.
  58    *
  59    * @param {cr.event.Event} event The event object for the audio data.
  60    * @private
  61    */
  62   SpeechManager.prototype.onAudioLevel_ = function(event) {
  63     var data = event.data;
  64     var level = 0;
  65     for (var i = 0; i < data.length; ++i)
  66       level += Math.abs(data[i]);
  67     level /= data.length;
  68     chrome.send('speechSoundLevel', [level]);
  69   };
  70
  71   /**
  72    * Called when the hotword recognizer is ready.
  73    *
  74    * @param {PluginManager} pluginManager The hotword plugin manager which gets
  75    *   ready.
  76    * @private
  77    */
  78   SpeechManager.prototype.onHotwordRecognizerReady_ = function(pluginManager) {
  79     this.pluginManager_ = pluginManager;
  80     this.audioManager_.addEventListener(
  81         'audio', pluginManager.sendAudioData.bind(pluginManager));
  82     this.setState_(SpeechState.READY);
  83   };
  84
  85   /**
  86    * Called when the hotword is recognized.
  87    *
  88    * @param {number} confidence The confidence store of the recognition.
  89    * @private
  90    */
  91   SpeechManager.prototype.onHotwordRecognized_ = function(confidence) {
  92     if (this.state != SpeechState.HOTWORD_RECOGNIZING)
  93       return;
  94     this.setState_(SpeechState.READY);
  95     this.pluginManager_.stopRecognizer();
  96     this.speechRecognitionManager_.start();
  97   };
  98
  99   /**
 100    * Called when the speech recognition has happened.
 101    *
 102    * @param {string} result The speech recognition result.
 103    * @param {boolean} isFinal Whether the result is final or not.
 104    */
 105   SpeechManager.prototype.onSpeechRecognized = function(result, isFinal) {
 106     chrome.send('speechResult', [result, isFinal]);
 107     if (isFinal)
 108       this.speechRecognitionManager_.stop();
 109   };
 110
 111   /**
 112    * Called when the speech recognition has started.
 113    */
 114   SpeechManager.prototype.onSpeechRecognitionStarted = function() {
 115     this.setState_(SpeechState.RECOGNIZING);
 116     chrome.send('setSpeechRecognitionState', ['on']);
 117   };
 118
 119   /**
 120    * Called when the speech recognition has ended.
 121    */
 122   SpeechManager.prototype.onSpeechRecognitionEnded = function() {
 123     // Restarts the hotword recognition.
 124     if (this.state != SpeechState.STOPPING && this.pluginManager_) {
 125       this.pluginManager_.startRecognizer();
 126       this.audioManager_.start();
 127       this.setState_(SpeechState.HOTWORD_RECOGNIZING);
 128     } else {
 129       this.audioManager_.stop();
 130     }
 131     chrome.send('setSpeechRecognitionState', ['off']);
 132   };
 133
 134   /**
 135    * Called when a speech has started.
 136    */
 137   SpeechManager.prototype.onSpeechStarted = function() {
 138     if (this.state == SpeechState.RECOGNIZING)
 139       chrome.send('setSpeechRecognitionState', ['in-speech']);
 140   };
 141
 142   /**
 143    * Called when a speech has ended.
 144    */
 145   SpeechManager.prototype.onSpeechEnded = function() {
 146     if (this.state == SpeechState.RECOGNIZING)
 147       chrome.send('setSpeechRecognitionState', ['on']);
 148   };
 149
 150   /**
 151    * Called when an error happened during the speech recognition.
 152    *
 153    * @param {SpeechRecognitionError} e The error object.
 154    */
 155   SpeechManager.prototype.onSpeechRecognitionError = function(e) {
 156     if (this.state != SpeechState.STOPPING)
 157       this.setState_(SpeechState.READY);
 158   };
 159
 160   /**
 161    * Starts the speech recognition session.
 162    */
 163   SpeechManager.prototype.start = function() {
 164     if (!this.pluginManager_)
 165       return;
 166
 167     if (this.state == SpeechState.HOTWORD_RECOGNIZING) {
 168       console.warn('Already in recognition state...');
 169       return;
 170     }
 171
 172     this.pluginManager_.startRecognizer();
 173     this.audioManager_.start();
 174     this.setState_(SpeechState.HOTWORD_RECOGNIZING);
 175   };
 176
 177   /**
 178    * Stops the speech recognition session.
 179    */
 180   SpeechManager.prototype.stop = function() {
 181     if (this.pluginManager_)
 182       this.pluginManager_.stopRecognizer();
 183
 184     // SpeechRecognition is asynchronous.
 185     this.audioManager_.stop();
 186     if (this.state == SpeechState.RECOGNIZING) {
 187       this.setState_(SpeechState.STOPPING);
 188       this.speechRecognitionManager_.stop();
 189     } else {
 190       this.setState_(SpeechState.READY);
 191     }
 192   };
 193
 194   /**
 195    * Toggles the current state of speech recognition.
 196    */
 197   SpeechManager.prototype.toggleSpeechRecognition = function() {
 198     if (this.state == SpeechState.RECOGNIZING) {
 199       this.audioManager_.stop();
 200       this.speechRecognitionManager_.stop();
 201     } else {
 202       if (this.pluginManager_)
 203         this.pluginManager_.stopRecognizer();
 204       if (this.audioManager_.state == speech.AudioState.STOPPED)
 205         this.audioManager_.start();
 206       this.speechRecognitionManager_.start();
 207     }
 208   };
 209
 210   return {
 211     SpeechManager: SpeechManager
 212   };
 213 });