Merge pull request #602 from watson-developer-cloud/fix/stt-streaming-silence

fix(STT): wait for audio to load when sending keep alive message

Author: mamoonraja

Examples/ExampleStreaming.cs

@@ -79,6 +79,10 @@ private IEnumerator CreateService()
                 yield return null;
 
             _service = new SpeechToTextService(authenticator);
+            if (!string.IsNullOrEmpty(_serviceUrl))
+            {
+                _service.SetServiceUrl(_serviceUrl);
+            }
             _service.StreamMultipart = true;
 
             Active = true;
@@ -192,9 +196,7 @@ private IEnumerator RecordingHandler()
 
                     yield return new WaitForSeconds(timeRemaining);
                 }
-
             }
-
             yield break;
         }
 

Scripts/Services/SpeechToText/V1/SpeechToTextServiceExtension.cs

@@ -44,7 +44,7 @@ public partial class SpeechToTextService : BaseService
         private const float WsKeepAliveInterval = 20.0f;
         /// <summary>
         /// If no listen state is received after start is sent within this time, we will timeout
-        /// and stop listening. 
+        /// and stop listening.
         /// </summary>
         private const float ListenTimeout = 10.0f;
         /// <summary>
@@ -77,9 +77,9 @@ public partial class SpeechToTextService : BaseService
         #endregion
 
         #region Private Data
-        private OnRecognize _listenCallback = null;        // Callback is set by StartListening()    
+        private OnRecognize _listenCallback = null;        // Callback is set by StartListening()
         private OnRecognizeSpeaker _speakerLabelCallback = null;
-        private WSConnector _listenSocket = null;          // WebSocket object used when StartListening() is invoked  
+        private WSConnector _listenSocket = null;          // WebSocket object used when StartListening() is invoked
         private bool _listenActive = false;
         private bool _audioSent = false;
         private bool _isListening = false;
@@ -541,6 +541,8 @@ private IEnumerator KeepAlive()
                     //  Temporary clip to use for KeepAlive
                     //  TODO: Generate small sound clip to send to the service to keep alive.
                     AudioClip _keepAliveClip = Resources.Load<AudioClip>("highHat");
+                    while (_keepAliveClip.loadState != AudioDataLoadState.Loaded)
+                        yield return null;
 
 #if ENABLE_DEBUGGING
                     Log.Debug("SpeechToText.KeepAlive()", "Sending keep alive.");