Naudio et Syn speech : erreur de référence nulle lors de la lecture d'un flux de mémoire

Question

Je suis presque sûr que je fais cela correctement mais je n'arrive pas à comprendre ce qui cause cette erreur ou comment la corriger. Toute aide serait appréciée. Le code est ci-dessous avec l'erreur en dessous.

Code. Je l'ai posté en entier car je ne sais pas ce qui est pertinent pour cette erreur.

    public class voiceStuff
  {
    public WaveInEvent waveInStream;
    private static StreamSpeechRecognizer _recognizer;
    WaveFileWriter writer;
    private MemoryStream mem;
    public void record()
    {

      waveInStream.NumberOfBuffers = 2;
      waveInStream.StartRecording();
      recognize();
    }

    public void recognize()
    {
      Console.ReadKey();
      waveInStream.StopRecording();
    }

    public voiceStuff()
    {
      Logger.LogReceived += Logger_LogReceived;
      waveInStream = new WaveInEvent();
      waveInStream.NumberOfBuffers =2;
      waveInStream.WaveFormat = new WaveFormat(16000, 1);
      mem = new MemoryStream();
      writer = new WaveFileWriter(mem, waveInStream.WaveFormat);
      waveInStream.DataAvailable += onDataAvailable;
      var modelPath = Path.Combine(Directory.GetCurrentDirectory(), "model/en-us");
      var dictionaryPath = Path.Combine(modelPath, "cmudict-en-us.dict");
      var languageModelPath = Path.Combine(modelPath, "en-us.lm.dmp");
      var configuration = new Configuration
      {
        AcousticModelPath = modelPath,
        DictionaryPath = dictionaryPath,
        LanguageModelPath = languageModelPath,
        UseGrammar = true,
        GrammarPath = "Models",
        GrammarName = "hello"
      };
      _recognizer = new StreamSpeechRecognizer(configuration);
      waveInStream.StartRecording();
      Console.ReadKey();
      waveInStream.StopRecording();
      Thread.Sleep(50);

      _recognizer.StartRecognition(mem, new TimeFrame(mem.Length));
      SpeechResult result = _recognizer.GetResult();
      _recognizer.StopRecognition();
      Console.WriteLine("result: " + result?.GetHypothesis());

      //syn speech
    }

    public void onDataAvailable(object sender, WaveInEventArgs e)
    {
      writer.Write(e.Buffer, 0, e.BytesRecorded);

    }
    static void Logger_LogReceived(object sender, LogReceivedEventArgs e)
    {
          Console.WriteLine(e.Message);
        }
      }

Erreur

     9/12/2016 9:55:42 PM Error StreamSpeechRecognizer System.NullReferenceException: Object reference not set to an instance of an object.
       at Syn.Speech.Linguist.Dictionary.TextDictionary.Allocate()
       at Syn.Speech.Linguist.Language.Grammar.Grammar.Allocate()
       at Syn.Speech.Linguist.Flat.FlatLinguist.Allocate()
       at Syn.Speech.Decoders.Search.SimpleBreadthFirstSearchManager.Allocate()
       at Syn.Speech.Recognizers.Recognizer.Allocate()
       at Syn.Speech.Api.StreamSpeechRecognizer.StartRecognition(Stream stream, TimeFrame timeFrame)
    9/12/2016 9:55:42 PM Error StreamSpeechRecognizer Syn.Speech.Helper.IllegalStateException: Expected state Ready actual state Allocating
       at Syn.Speech.Recognizers.Recognizer.CheckState(State desiredState)
       at Syn.Speech.Recognizers.Recognizer.Recognize(String referenceText)
       at Syn.Speech.Api.AbstractSpeechRecognizer.GetResult()
    9/12/2016 9:55:42 PM Error StreamSpeechRecognizer Syn.Speech.Helper.IllegalStateException: Expected state Ready actual state Allocating
       at Syn.Speech.Recognizers.Recognizer.CheckState(State desiredState)
       at Syn.Speech.Recognizers.Recognizer.Deallocate()
       at Syn.Speech.Api.StreamSpeechRecognizer.StopRecognition()

Answer 1

Au minimum, vous devrez Dispose votre WaveFileWriter afin de finaliser la structure du fichier WAV. Attention toutefois à ne pas jeter également le flux de mémoire. Je l'enveloppe habituellement dans la classe utilitaire de NAudio IgnoreDisposeStream

Dans ce cas, vous devez rembobiner votre MemoryStream au début avant de le transmettre à la reconnaissance vocale.