Thanks to the amazing work of Casey Chesnut I've figured out how to determine the IPA phones for a given string. Now I just have to figure out how to convert from IPA phones to SAPI symbols, but that's for a separate topic (see here for how to get the SAPI phonemes from a text string).
using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.IO;
using System.Speech.Recognition;
using System.Speech.Synthesis;
using System.Windows.Forms;
namespace SpeechTest
{
class Program
{
static void Main(string[] args)
{
string MyText = "dolphins"; // Initialze string for storing word (or words) of interest
string MyPronunciation = GetPronunciationFromText(MyText.Trim()); // Get IPA pronunciations of MyTe
MessageBox.Show(MyText + " = " + MyPronunciation); // Output MyText and MyPronunciation
}
public static string recoPhonemes;
public static string GetPronunciationFromText(string MyWord)
{
//this is a trick to figure out phonemes used by synthesis engine
//txt to wav
using (MemoryStream audioStream = new MemoryStream())
{
using (SpeechSynthesizer synth = new SpeechSynthesizer())
{
synth.SetOutputToWaveStream(audioStream);
PromptBuilder pb = new PromptBuilder();
//pb.AppendBreak(PromptBreak.ExtraSmall); //'e' wont be recognized if this is large, or non-existent?
//synth.Speak(pb);
synth.Speak(MyWord);
//synth.Speak(pb);
synth.SetOutputToNull();
audioStream.Position = 0;
//now wav to txt (for reco phonemes)
recoPhonemes = String.Empty;
GrammarBuilder gb = new GrammarBuilder(MyWord);
Grammar g = new Grammar(gb); //TODO the hard letters to recognize are 'g' and 'e'
SpeechRecognitionEngine reco = new SpeechRecognitionEngine();
reco.SpeechHypothesized += new EventHandler<SpeechHypothesizedEventArgs>(reco_SpeechHypothesized);
reco.SpeechRecognitionRejected += new EventHandler<SpeechRecognitionRejectedEventArgs>(reco_SpeechRecognitionRejected);
reco.UnloadAllGrammars(); //only use the one word grammar
reco.LoadGrammar(g);
reco.SetInputToWaveStream(audioStream);
RecognitionResult rr = reco.Recognize();
reco.SetInputToNull();
if (rr != null)
{
recoPhonemes = StringFromWordArray(rr.Words, WordType.Pronunciation);
}
//txtRecoPho.Text = recoPhonemes;
return recoPhonemes;
}
}
}
public static string StringFromWordArray(ReadOnlyCollection<RecognizedWordUnit> words, WordType type)
{
string text = "";
foreach (RecognizedWordUnit word in words)
{
string wordText = "";
if (type == WordType.Text || type == WordType.Normalized)
{
wordText = word.Text;
}
else if (type == WordType.Lexical)
{
wordText = word.LexicalForm;
}
else if (type == WordType.Pronunciation)
{
wordText = word.Pronunciation;
//MessageBox.Show(word.LexicalForm);
}
else
{
throw new InvalidEnumArgumentException(String.Format("[0}: is not a valid input", type));
}
//Use display attribute
if ((word.DisplayAttributes & DisplayAttributes.OneTrailingSpace) != 0)
{
wordText += " ";
}
if ((word.DisplayAttributes & DisplayAttributes.TwoTrailingSpaces) != 0)
{
wordText += " ";
}
if ((word.DisplayAttributes & DisplayAttributes.ConsumeLeadingSpaces) != 0)
{
wordText = wordText.TrimStart();
}
if ((word.DisplayAttributes & DisplayAttributes.ZeroTrailingSpaces) != 0)
{
wordText = wordText.TrimEnd();
}
text += wordText;
}
return text;
}
public static void reco_SpeechHypothesized(object sender, SpeechHypothesizedEventArgs e)
{
recoPhonemes = StringFromWordArray(e.Result.Words, WordType.Pronunciation);
}
public static void reco_SpeechRecognitionRejected(object sender, SpeechRecognitionRejectedEventArgs e)
{
recoPhonemes = StringFromWordArray(e.Result.Words, WordType.Pronunciation);
}
}
public enum WordType
{
Text,
Normalized = Text,
Lexical,
Pronunciation
}
}
// Credit for method of retrieving IPA pronunciation from a string goes to Casey Chesnut (http://www.mperfect.net/speechSamples/)