Merge pull request #3764 from luis-valverde-ms/dictation_handler

Create DictationHandler script for easy access to dictation service

Author: keveleigh

Assets/MixedRealityToolkit.SDK/Features/Input/Handlers/DictationHandler.cs

@@ -0,0 +1,126 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+
+using UnityEngine;
+using UnityEngine.Events;
+
+namespace Microsoft.MixedReality.Toolkit.Input
+{
+    /// <summary>
+    /// Script used to start and stop recording sessions in the current dictation system and report the transcribed text via UnityEvents.
+    /// For this script to work, a dictation system like 'Windows Dictation Input Provider' must be added to the Data Providers in the Input System profile.
+    /// </summary>
+    public class DictationHandler : BaseInputHandler, IMixedRealityDictationHandler
+    {
+        [SerializeField]
+        [Tooltip("Time length in seconds before the dictation session ends due to lack of audio input in case there was no audio heard in the current session")]
+        private float initialSilenceTimeout = 5f;
+
+        [SerializeField]
+        [Tooltip("Time length in seconds before the dictation session ends due to lack of audio input.")]
+        private float autoSilenceTimeout = 20f;
+
+        [SerializeField]
+        [Tooltip("Length in seconds for the dictation service to listen")]
+        private int recordingTime = 10;
+
+        [SerializeField]
+        [Tooltip("Whether recording should start automatically on start")]
+        private bool startRecordingOnStart = false;
+
+        [System.Serializable]
+        public class StringUnityEvent : UnityEvent<string> { }
+
+        /// <summary>
+        /// Event raised while the user is talking. As the recognizer listens, it provides text of what it's heard so far.
+        /// </summary>
+        public StringUnityEvent OnDictationHypothesis;
+
+        /// <summary>
+        /// Event raised after the user pauses, typically at the end of a sentence. Contains the full recognized string so far.
+        /// </summary>
+        public StringUnityEvent OnDictationResult;
+
+        /// <summary>
+        /// Event raised when the recognizer stops. Contains the final recognized string.
+        /// </summary>
+        public StringUnityEvent OnDictationComplete;
+
+        /// <summary>
+        /// Event raised when an error occurs. Contains the string representation of the error reason.
+        /// </summary>
+        public StringUnityEvent OnDictationError;
+
+        private IMixedRealityDictationSystem dictationSystem;
+
+        /// <summary>
+        /// Start a recording session in the dictation system.
+        /// </summary>
+        public void StartRecording()
+        {
+            if (dictationSystem != null)
+            {
+                dictationSystem.StartRecording(gameObject, initialSilenceTimeout, autoSilenceTimeout, recordingTime);
+            }
+        }
+
+        /// <summary>
+        /// Stop a recording session in the dictation system.
+        /// </summary>
+        public void StopRecording()
+        {
+            if (dictationSystem != null)
+            {
+                dictationSystem.StopRecording();
+            }
+        }
+
+        #region IMixedRealityDictationHandler implementation
+
+        void IMixedRealityDictationHandler.OnDictationHypothesis(DictationEventData eventData)
+        {
+            OnDictationHypothesis.Invoke(eventData.DictationResult);
+        }
+
+        void IMixedRealityDictationHandler.OnDictationResult(DictationEventData eventData)
+        {
+            OnDictationResult.Invoke(eventData.DictationResult);
+        }
+
+        void IMixedRealityDictationHandler.OnDictationComplete(DictationEventData eventData)
+        {
+            OnDictationComplete.Invoke(eventData.DictationResult);
+        }
+
+        void IMixedRealityDictationHandler.OnDictationError(DictationEventData eventData)
+        {
+            OnDictationError.Invoke(eventData.DictationResult);
+        }
+
+        #endregion IMixedRealityDictationHandler implementation
+
+        #region MonoBehaviour implementation
+
+        protected override void Start()
+        {
+            base.Start();
+
+            dictationSystem = MixedRealityToolkit.Instance.GetService<IMixedRealityDictationSystem>();
+            Debug.Assert(dictationSystem != null, "No dictation system found. In order to use dictation, add a dictation system like 'Windows Dictation Input Provider' to the Data Providers in the Input System profile");
+
+            if (startRecordingOnStart)
+            {
+                StartRecording();
+            }
+        }
+
+        protected override void OnDisable()
+        {
+            StopRecording();
+
+            base.OnDisable();
+        }
+
+        #endregion MonoBehaviour implementation
+    }
+}