Android语音识别作为Android 4.1和4.2上的服务

Question

我已经成功地将连续语音识别工作(使用SpeechRecognizer类)作为服务,适用于4.1以上的所有Android版本.我的问题是关于让它在版本4.1和4.2上运行,因为众所周知,有一个问题是,API没有按照文档识别启动后几秒钟的记录,如果没有检测到语音输入那么它就像如果语音识别器无声地死亡.(http://code.google.com/p/android/issues/detail?id=37883)

我找到了一个问题,提出解决这个问题的方法(语音识别在几秒钟后停止监听),但我不确定如何实现此解决方案所需的处理程序.我知道这种解决方法每隔几秒钟会发生一次"嘟嘟"声,但对我来说,获得连续的语音识别更为重要.

如果有人有任何其他替代解决方法,那么我也想听听.

Answer 1

这是Android版本4.1.1的解决方法.

public class MyService extends Service
{
    protected AudioManager mAudioManager; 
    protected SpeechRecognizer mSpeechRecognizer;
    protected Intent mSpeechRecognizerIntent;
    protected final Messenger mServerMessenger = new Messenger(new IncomingHandler(this));

    protected boolean mIsListening;
    protected volatile boolean mIsCountDownOn;
    private boolean mIsStreamSolo;

    static final int MSG_RECOGNIZER_START_LISTENING = 1;
    static final int MSG_RECOGNIZER_CANCEL = 2;

    @Override
    public void onCreate()
    {
        super.onCreate();
        mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE); 
        mSpeechRecognizer = SpeechRecognizer.createSpeechRecognizer(this);
        mSpeechRecognizer.setRecognitionListener(new SpeechRecognitionListener());
        mSpeechRecognizerIntent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
        mSpeechRecognizerIntent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
                                         RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
        mSpeechRecognizerIntent.putExtra(RecognizerIntent.EXTRA_CALLING_PACKAGE,
                                         this.getPackageName());
    }

    protected static class IncomingHandler extends Handler
    {
        private WeakReference<MyService> mtarget;

        IncomingHandler(MyService target)
        {
            mtarget = new WeakReference<MyService>(target);
        }


        @Override
        public void handleMessage(Message msg)
        {
            final MyService target = mtarget.get();

            switch (msg.what)
            {
                case MSG_RECOGNIZER_START_LISTENING:

                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
                    {
                        // turn off beep sound  
                        if (!mIsStreamSolo)
                        {
                            mAudioManager.setStreamSolo(AudioManager.STREAM_VOICE_CALL, true);
                            mIsStreamSolo = true;
                        }
                    }
                     if (!target.mIsListening)
                     {
                         target.mSpeechRecognizer.startListening(target.mSpeechRecognizerIntent);
                         target.mIsListening = true;
                        //Log.d(TAG, "message start listening"); //$NON-NLS-1$
                     }
                     break;

                 case MSG_RECOGNIZER_CANCEL:
                    if (mIsStreamSolo)
                   {
                        mAudioManager.setStreamSolo(AudioManager.STREAM_VOICE_CALL, false);
                        mIsStreamSolo = false;
                   }
                      target.mSpeechRecognizer.cancel();
                      target.mIsListening = false;
                      //Log.d(TAG, "message canceled recognizer"); //$NON-NLS-1$
                      break;
             }
       } 
    } 

    // Count down timer for Jelly Bean work around
    protected CountDownTimer mNoSpeechCountDown = new CountDownTimer(5000, 5000)
    {

        @Override
        public void onTick(long millisUntilFinished)
        {
            // TODO Auto-generated method stub

        }

        @Override
        public void onFinish()
        {
            mIsCountDownOn = false;
            Message message = Message.obtain(null, MSG_RECOGNIZER_CANCEL);
            try
            {
                mServerMessenger.send(message);
                message = Message.obtain(null, MSG_RECOGNIZER_START_LISTENING);
                mServerMessenger.send(message);
            }
            catch (RemoteException e)
            {

            }
        }
    };

    @Override
    public void onDestroy()
    {
        super.onDestroy();

        if (mIsCountDownOn)
        {
            mNoSpeechCountDown.cancel();
        }
        if (mSpeechRecognizer != null)
        {
            mSpeechRecognizer.destroy();
        }
    }

    protected class SpeechRecognitionListener implements RecognitionListener
    {

        @Override
        public void onBeginningOfSpeech()
        {
            // speech input will be processed, so there is no need for count down anymore
            if (mIsCountDownOn)
            {
                mIsCountDownOn = false;
                mNoSpeechCountDown.cancel();
            }               
            //Log.d(TAG, "onBeginingOfSpeech"); //$NON-NLS-1$
        }

        @Override
        public void onBufferReceived(byte[] buffer)
        {

        }

        @Override
        public void onEndOfSpeech()
        {
            //Log.d(TAG, "onEndOfSpeech"); //$NON-NLS-1$
         }

        @Override
        public void onError(int error)
        {
            if (mIsCountDownOn)
            {
                mIsCountDownOn = false;
                mNoSpeechCountDown.cancel();
            }
             mIsListening = false;
             Message message = Message.obtain(null, MSG_RECOGNIZER_START_LISTENING);
             try
             {
                    mServerMessenger.send(message);
             }
             catch (RemoteException e)
             {

             }
            //Log.d(TAG, "error = " + error); //$NON-NLS-1$
        }

        @Override
        public void onEvent(int eventType, Bundle params)
        {

        }

        @Override
        public void onPartialResults(Bundle partialResults)
        {

        }

        @Override
        public void onReadyForSpeech(Bundle params)
        {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
            {
                mIsCountDownOn = true;
                mNoSpeechCountDown.start();

            }
            Log.d(TAG, "onReadyForSpeech"); //$NON-NLS-1$
        }

        @Override
        public void onResults(Bundle results)
        {
            //Log.d(TAG, "onResults"); //$NON-NLS-1$

        }

        @Override
        public void onRmsChanged(float rmsdB)
        {

        }

    }
}

02/16/2013 - 如果您在应用中使用"文字转语音",请修复提示音,确保在onResults中关闭Solo流

Answer 2

如果你真的想要实现没有互联网连接连续收听你需要考虑的第三方软件包,其中之一是CMUSphinx,检查Pocketsphinx机器人演示,例如如何高效地在离线听关键词和具体的命令做出反应就像一个关键短语"哦强大的电脑".这样做的代码很简单:

你创建一个识别器,只需添加关键字定位搜索:

recognizer = defaultSetup()
        .setAcousticModel(new File(modelsDir, "hmm/en-us-semi"))
        .setDictionary(new File(modelsDir, "lm/cmu07a.dic"))
        .setKeywordThreshold(1e-5f)
        .getRecognizer();

recognizer.addListener(this);
recognizer.addKeywordSearch(KWS_SEARCH_NAME, KEYPHRASE);
switchSearch(KWS_SEARCH_NAME);

并定义一个监听器:

@Override
public void onPartialResult(Hypothesis hypothesis) {
    String text = hypothesis.getHypstr();
    if (text.equals(KEYPHRASE))
      //  do something
} 

Answer 3

对于那些试图使哔哔声静音的人,重新调整@HoanNguyen的答案非常好,但要小心,如api中所说的setStreamSolo是累积的,所以如果语音识别出错,则会调用错误(例如没有互联网连接)然后一次又一次地调用setStremSolo true会导致你的应用程序使整个手机静音(非常糟糕)!解决方案是将setStremMute(false)添加到speechRecognizer onError.

Answer 4

看看我的演示应用程序:https: //github.com/galrom/ContinuesVoiceRecognition

我建议使用PockeySphix和SpeechRecognizer.