在Cupcake中，Android引入了对语音识别的支持。为了进行语音识别，以语音拨号为例，在语音识别引擎中，首先要启动麦克风，然后创建一个语音识别器，接着扫描电话本，查看语法分析数据库g2g文件是否陈旧。如果陈旧，则重构g2g文件，否则就加载g2g文件。然后启动语音识别器，进行语音的捕获并等待处理结果。当处理完成后，语音识别引擎会返回一组Intent，后停止麦克风和语音识别器。对语音拨号的具体处理过程如下：

public void recognize(VoiceDialerActivity voiceDialerActivity,File micFile, File contactsFile, String codec)
      {
          InputStream mic=null;
          boolean recognizerStarted=false;
          try {
              if (Config.LOGD) Log.d(TAG, "start");
              mVoiceDialerActivity=voiceDialerActivity; //启动voiceDialerActivity
              mLogger=null;
              if (RecognizerLogger.isEnabled(mVoiceDialerActivity))
                  {
                      mLogger=new RecognizerLogger(mVoiceDialerActivity);
                  }
          if (Config.LOGD) Log.d(TAG, "start new MicrophoneInputStream");
              if (micFile !=null)
                  {
                      mic=new FileInputStream(micFile); //创建输入流
                      WaveHeader hdr=new WaveHeader(); //音频格式为WAV
                      hdr.read(mic); //设置输入设备
                  }
              else
              {
                  mic=new MicrophoneInputStream(SAMPLE_RATE, SAMPLE_RATE * 15);
              }
      voiceDialerActivity.onMicrophoneStart(); //提醒用户输入语音
      //创建新识别器
      if (Config.LOGD) Log.d(TAG, "start new Recognizer");
      if (mSrec==null) mSrec=new Recognizer(SREC_DIR + "/baseline11k.par");
      if (Config.LOGD) Log.d(TAG, "start getVoiceContacts");
      List contacts=contactsFile !=null ?
      VoiceContact.getVoiceContactsFromFile(contactsFile) :
      VoiceContact.getVoiceContacts(mVoiceDialerActivity);
      if (mLogger !=null) mLogger.logContacts(contacts);
      //产生g2g语法文件名
      File g2g=mVoiceDialerActivity.getFileStreamPath("voicedialer."+Integer.toHexString(contacts.hashCode()) + ".g2g");
      //如果当前g2g文件过期，重构g2g文件
      if (!g2g.exists())
      {
          deleteAllG2GFiles(mVoiceDialerActivity);
          if (mSrecGrammar !=null)
              {
                  mSrecGrammar.destroy();
                   mSrecGrammar=null;
              }
      //加载空语法器
      if (Config.LOGD) Log.d(TAG, "start new Grammar");
      mSrecGrammar=mSrec.new Grammar(SREC_DIR + "/grammars/VoiceDialer.g2g"); //语法分析数据库VoiceDialer.g2g"
      mSrecGrammar.setupRecognizer(); ///启动语音识别器
      if (Config.LOGD) Log.d(TAG, "start grammar.resetAllSlots");
      mSrecGrammar.resetAllSlots();
      addOpenEntriesToGrammar();
      addNameEntriesToGrammar(contacts);
      //编译语法器
      if (Config.LOGD) Log.d(TAG, "start grammar.compile");
      mSrecGrammar.compile();
      //更新g2g文件
      if (Config.LOGD) Log.d(TAG, "start grammar.save " + g2g.getPath());
      g2g.getParentFile().mkdirs();
      mSrecGrammar.save(g2g.getPath());
      }
      else if (mSrecGrammar==null)
      {
          if (Config.LOGD) Log.d(TAG, "start new Grammar loading " + g2g);
          mSrecGrammar=mSrec.new Grammar(g2g.getPath());
          mSrecGrammar.setupRecognizer();
      }
      //启动识别过程
      if (Config.LOGD) Log.d(TAG, "start mSrec.start");
      mSrec.start();
      recognizerStarted=true;
      if (mLogger !=null) mic=mLogger.logInputStream(mic, SAMPLE_RATE);
      while (true) {
          if (Thread.interrupted()) throw new InterruptedException();
          int event=mSrec.advance();
      if (event !=Recognizer.EVENT_INCOMPLETE &&event !=Recognizer.EVENT_NEED_MORE_AUDIO)
      {
          if (Config.LOGD) Log.d(TAG, "start advance()="+Recognizer.eventToString(event));
      }
      switch (event) {
          case Recognizer.EVENT_INCOMPLETE:
          case Recognizer.EVENT_STARTED:
          case Recognizer.EVENT_START_OF_VOICING:
          case Recognizer.EVENT_END_OF_VOICING:
          continue;
          case Recognizer.EVENT_RECOGNITION_RESULT:
          onRecognitionSuccess(); //识别结果
          break;
          case Recognizer.EVENT_NEED_MORE_AUDIO:
          mSrec.putAudio(mic); //继续输入语音
          continue;
          default:
      mVoiceDialerActivity.onRecognitionFailure(Recognizer.eventToString(event));
          break;
              }
      break;
          }
      }
      catch (InterruptedException e)
      {
          if (Config.LOGD) Log.d(TAG, "start interrupted "+e);
      }
      catch(IOException e)
      {
          if (Config.LOGD) Log.d(TAG, "start new Srec failed "+e);
          mVoiceDialerActivity.onRecognitionError(e.toString());
      }
      finally {
      //停止麦克风
      try {
          if (mic !=null) mic.close();
      }
      catch (IOException ex)
      {
          if (Config.LOGD) Log.d(TAG, "start - mic.close failed - " + ex);
      }
      mic=null;
      //关闭识别器
      if (Config.LOGD) Log.d(TAG, "start mSrec.stop");
      if (mSrec !=null && recognizerStarted) mSrec.stop();
      try {
          if (mLogger !=null) mLogger.close();
      }
      catch (IOException ex)
      {
          if (Config.LOGD) Log.d(TAG, "start - mLoggger.close failed - " + ex);
      }
      mLogger=null;
      }
      if (Config.LOGD) Log.d(TAG, "start bye");
      }