/// <summary>
/// Starts service
/// </summary>
protected override void Start()
{
try
{
if (_state == null)
{
_state = new SpeechRecognizerState();
}
// Set up speech recognition engine
if (_state.IgnoreAudioInput)
{
_state.Recognizer.SetInputToNull();
}
else
{
_state.Recognizer.SetInputToDefaultAudioDevice();
}
// Register event handlers for speech recognition
_state.Recognizer.RecognizerUpdateReached += RecognizerUpdateReachedHandler;
_state.Recognizer.LoadGrammarCompleted += LoadGrammarCompletedHandler;
_state.Recognizer.SpeechDetected += SpeechDetectedHandler;
_state.Recognizer.SpeechRecognized += SpeechRecognizedHandler;
_state.Recognizer.SpeechRecognitionRejected += SpeechRecognitionRejectedHandler;
}
catch (Exception exception)
{
// Fatal exception during startup, shutdown service
LogError(LogGroups.Activation, exception);
_state.Recognizer.Dispose();
DefaultDropHandler(new DsspDefaultDrop());
return;
}
SpawnIterator(LoadGrammarOnStartup);
}
public IEnumerator <ITask> ReplaceHandler(Replace replace)
{
SpeechRecognizerState newState = replace.Body;
#region Set up load grammar request, load grammar and on success store new grammar in state
// Set up load grammar request
LoadGrammarRequest loadRequest = new LoadGrammarRequest();
loadRequest.GrammarType = newState.GrammarType;
loadRequest.SrgsFileLocation = newState.SrgsFileLocation;
loadRequest.DictionaryGrammar = newState.DictionaryGrammar;
// Load new grammar
SuccessFailurePort loadGrammarPort = new SuccessFailurePort();
SpawnIterator <LoadGrammarRequest, SuccessFailurePort>(
loadRequest,
loadGrammarPort,
LoadGrammar
);
// Check loading outcome
yield return((Choice)loadGrammarPort);
Exception exception = (Exception)loadGrammarPort;
if (exception != null)
{
LogWarning(exception);
replace.ResponsePort.Post(Fault.FromCodeSubcodeReason(
W3C.Soap.FaultCodes.Receiver,
DsspFaultCodes.OperationFailed,
exception.Message
));
yield break;
}
#endregion
#region Check new state's IgnoreAudioInput flag and start recognition engine if necessary
if (newState.IgnoreAudioInput != _state.IgnoreAudioInput)
{
_state.IgnoreAudioInput = newState.IgnoreAudioInput;
if (_state.IgnoreAudioInput)
{
// Stop engine and switch to ignoring audio input
_state.Recognizer.RecognizeAsyncCancel();
_state.Recognizer.SetInputToNull();
}
else
{
_state.Recognizer.SetInputToDefaultAudioDevice();
// Because old state ignored audio input the engine is stopped, now that
// we switched to listening to audio input the engine needs to be started
if (_state.Recognizer.Grammars.Count > 0)
{
_state.Recognizer.RecognizeAsync(RecognizeMode.Multiple);
}
}
}
#endregion
SaveState(_state);
// Notify subscribers of state change
replace.Body = _state;
SendNotification <Replace>(_subMgrPort, replace);
replace.ResponsePort.Post(DefaultReplaceResponseType.Instance);
}