RecognitionResult::GetAudioForWordRange Method (RecognizedWordUnit^, RecognizedWordUnit^)

.NET Framework (current version)

Gets a section of the audio that is associated with a specific range of words in the recognition result.

Namespace: System.Speech.Recognition
Assembly: System.Speech (in System.Speech.dll)

Syntax

public:
RecognizedAudio^ GetAudioForWordRange(
	RecognizedWordUnit^ firstWord,
	RecognizedWordUnit^ lastWord
)

Parameters

firstWord: Type: System.Speech.Recognition::RecognizedWordUnit^
The first word in the range.

lastWord: Type: System.Speech.Recognition::RecognizedWordUnit^
The last word in the range.

Return Value

Type: System.Speech.Recognition::RecognizedAudio^

The section of audio associated with the word range.

Exceptions

Exception	Condition
NullReferenceException	The recognizer generated the result from a call to EmulateRecognize or EmulateRecognizeAsync methods of the SpeechRecognizer or SpeechRecognitionEngine objects.

Remarks

To get the complete audio associated with the recognition result, use the Audio property.

The following example creates a grammar to accept name input and attaches to it a handler for the SpeechRecognized event. The grammar uses a wildcard for the name element of the phrase. The event handler uses the audio from the wildcard to create and play a greeting prompt.


private Grammar CreateNameInputGrammar()
{
  GrammarBuilder wildcardBuilder = new GrammarBuilder();
  wildcardBuilder.AppendWildcard();
  SemanticResultKey nameKey =
    new SemanticResultKey("Name", wildcardBuilder);

  GrammarBuilder nameBuilder =
    new GrammarBuilder("My name is");
  nameBuilder.Append(nameKey);

  Grammar nameGrammar = new Grammar(nameBuilder);
  nameGrammar.Name = "Name input";

  nameGrammar.SpeechRecognized +=
    new EventHandler<SpeechRecognizedEventArgs>(
      NameInputHandler);

  return nameGrammar;
}

// Handle the SpeechRecognized event for the name grammar.
private void NameInputHandler(object sender, SpeechRecognizedEventArgs e)
{
  if (e.Result == null) return;

  RecognitionResult result = e.Result;
  SemanticValue semantics = e.Result.Semantics;

  if (semantics.ContainsKey("Name"))
  {
    RecognizedAudio nameAudio =
      result.GetAudioForWordRange(
        result.Words[3], result.Words[result.Words.Count - 1]);

    // Save the audio. Create a directory and file as necessary.
    FileInfo fi = new FileInfo(@"C:\temp\temp.wav");
    if (!fi.Directory.Exists)
    {
      fi.Directory.Create();
    }
    FileStream stream = new FileStream(fi.FullName, FileMode.Create);
    nameAudio.WriteToWaveStream(stream);
    stream.Close();

    // Greet the person using the saved audio.
    SpeechSynthesizer synthesizer = new SpeechSynthesizer();
    PromptBuilder builder = new PromptBuilder();
    builder.AppendText("Hello");
    builder.AppendAudio(fi.FullName);
    synthesizer.Speak(builder);
  }
}

Version Information

.NET Framework
Available since 3.0