我已经设法让连续语音识别工作（使用 SpeechRecognizer 类）作为所有 Android 版本高达 4.1 的服务。我的问题是让它在 4.1 和 4.2 版本上运行，因为众所周知，API 在语音识别开始后的几秒钟内没有按照记录的那样运行，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无息地死去。（http://code.google.com/p/android/issues/detail?id=37883）
我发现了一个问题，它提出了解决此问题的方法（语音识别在几秒钟后停止收听），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就会发出“哔”声，但获得持续的语音识别对我来说更重要。
如果有人有任何其他替代解决方法，那么我也想听听。
这是针对 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)
{
}
}
}
2013 年 2 月 16 日 - 如果您在应用程序中使用文本到语音，请修复哔声，确保关闭 onResults 中的 Solo 流
如果你真的想在没有互联网连接的情况下实现连续收听，你需要考虑第三方包，其中之一是 CMUSphinx，查看Pocketsphinx android 演示，例如如何在离线时有效地收听关键字并对特定命令做出反应，如关键短语“哦，强大的计算机”。执行此操作的代码很简单：
您创建一个识别器并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
}
对于任何试图使哔哔声静音的人，重新评分@HoanNguyen 答案非常好，但要小心，如 api set setStreamSolo 中所说的那样是累积的，所以如果语音识别中有错误并且错误被调用（例如没有互联网连接）然后 setStremSolo true 被一次又一次地调用，这将导致您的应用程序静音整个手机（非常糟糕）！解决方案是将 setStremMute(false) 添加到 SpeechRecognizer onError。
查看我的演示应用程序： https ://github.com/galrom/ContinuesVoiceRecognition
我建议同时使用 PockeySphix 和 SpeechRecognizer。