UnityのGoogle音声認識

• Google Cloud Speech Recognition [VR\AR\Desktop\Desktop] 　を買って、シーン内にGCSpeechRecognitionというPrefabを入れる（Assets/FrostweepGames/GCSpeechRecognition/Prefabs/にある）。

• Prefabの設定のApi Keyに、Googleから取得した音声認識用のAPI Keyを入れる。

• Prefabの設定のConfigsの中のDefault Languageを設定（スクリプト内で設定も可能）

• GCSpeechRecognitionオブジェクトに、以下のスクリプト(GoogleVoiceRecognition.cs)を追加。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using FrostweepGames.Plugins.GoogleCloud.SpeechRecognition;

public class GoogleVoiceRecognition : MonoBehaviour
{
    public delegate void onRecognized(SpeechRecognitionResult [] speechRecognitionResults);



    private GCSpeechRecognition speechRecognition;
    private bool bRuntimeDetection = false;


    // Start is called before the first frame update
    void Start()
    {
        speechRecognition = GCSpeechRecognition.Instance;
        speechRecognition.RecognitionSuccessEvent += RecognitionSuccessEventHandler;
        speechRecognition.NetworkRequestFailedEvent += SpeechRecognizedFailedEventHandler;
        speechRecognition.LongRecognitionSuccessEvent += LongRecognitionSuccessEventHandler;

        // 言語を入れ替える
        //speechRecognition.SetLanguage(Enumerators.LanguageCode.ja_JP);
    }

    private void OnDestroy()
    {
        speechRecognition.RecognitionSuccessEvent -= RecognitionSuccessEventHandler;
        speechRecognition.NetworkRequestFailedEvent -= SpeechRecognizedFailedEventHandler;
        speechRecognition.LongRecognitionSuccessEvent -= LongRecognitionSuccessEventHandler;
    }

    public void StartRecord(bool _bRuntimeDetection=false)
    {
        bRuntimeDetection = _bRuntimeDetection;
        speechRecognition.StartRecord(bRuntimeDetection); // true: runtime voice detection on (Does not seem to work

        onRecognizedCallback = null;
    }

    onRecognized onRecognizedCallback = null;
    public void StopRecord(onRecognized _onRecognizedCallback)
    {
        onRecognizedCallback = null;
        if (_onRecognizedCallback == null)
        {
            Debug.Log("Please supply callback!");
        }
        onRecognizedCallback = _onRecognizedCallback;
        speechRecognition.StopRecord();
   }

    private void SpeechRecognizedFailedEventHandler(string obj, long requestIndex)
    {
        Debug.Log("Error:" + obj);
        if (onRecognizedCallback != null)
        {
            onRecognizedCallback(null);
        }
    }

    private void RecognitionSuccessEventHandler(RecognitionResponse obj, long requestIndex)
    {
        Debug.Log("Recognition success");

        if (obj != null && obj.results.Length > 0)
        {
            if (onRecognizedCallback != null)
            {
                onRecognizedCallback(obj.results);
            }
        }
        else
        {
            Debug.Log("Speech Recognition succeeded! Words are no detected.");
            if (onRecognizedCallback != null)
            {
                onRecognizedCallback(null);
            }
        }
    }

    private void LongRecognitionSuccessEventHandler(OperationResponse operation, long index)
    {
        Debug.Log("Recognition success");


        if (operation != null && operation.response.results.Length > 0)
        {
            if (onRecognizedCallback != null)
            {
                onRecognizedCallback(operation.response.results);
            }

        }
        else
        {
            Debug.Log("Error:Speech Recognition succeeded! Words are no detected.");
            if (onRecognizedCallback != null)
            {
                onRecognizedCallback(null);
            }
        }
    }
}

• 使う側のスクリプトを用意

  • 必要ライブラリのインポート

  using FrostweepGames.Plugins.GoogleCloud.SpeechRecognition;
  

  • 認識オブジェクトの取得

  GameObject gvrObj = GameObject.Find("GCSpeechRecognition");
  GoogleVoiceRecognition googleVoiceRecognition = gvrObj.GetComponent<GoogleVoiceRecognition>();
  

  • 録音開始

  googleVoiceRecognition.StartRecord();
  

  • 録音停止＆認識開始。認識結果はコールバックにて受け取る。

  googleVoiceRecognition.StopRecord( (SpeechRecognitionResult[] srr)=> {
  if( srr == null ){
   Debug.Log("Recognition failed.");
   return;
  }
  foreach (var result in srr)
  {
   foreach (var alternative in result.alternatives)
   {
     Debug.Log("Transcripted:" + alternative.transcript);
   }
  }
  } );