diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionGraph.cs
index 0921a7129..c698a74aa 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionGraph.cs	
@@ -30,7 +30,7 @@ public float minDetectionConfidence
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceDetectionsOutput
     {
-      add => _faceDetectionsStream.AddListener(value);
+      add => _faceDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _faceDetectionsStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionSolution.cs
index 05a8b8335..0532346d8 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Face Detection/FaceDetectionSolution.cs	
@@ -51,7 +51,7 @@ protected override IEnumerator WaitForNextValue()
     private void OnFaceDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(Detection.Parser);
+      var value = packet == null ? default : packet.GetProtoList(Detection.Parser);
       _faceDetectionsAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshGraph.cs
index 2cb1d4a62..12ec99e03 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshGraph.cs	
@@ -51,25 +51,25 @@ public float minTrackingConfidence
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceDetectionsOutput
     {
-      add => _faceDetectionsStream.AddListener(value);
+      add => _faceDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _faceDetectionsStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnMultiFaceLandmarksOutput
     {
-      add => _multiFaceLandmarksStream.AddListener(value);
+      add => _multiFaceLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _multiFaceLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceRectsFromLandmarksOutput
     {
-      add => _faceRectsFromLandmarksStream.AddListener(value);
+      add => _faceRectsFromLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _faceRectsFromLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceRectsFromDetectionsOutput
     {
-      add => _faceRectsFromDetectionsStream.AddListener(value);
+      add => _faceRectsFromDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _faceRectsFromDetectionsStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshSolution.cs
index 705b6d4a4..0b74ea3b2 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Face Mesh/FaceMeshSolution.cs	
@@ -77,28 +77,28 @@ protected override IEnumerator WaitForNextValue()
     private void OnFaceDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(Detection.Parser);
+      var value = packet == null ? default : packet.GetProtoList(Detection.Parser);
       _faceDetectionsAnnotationController.DrawLater(value);
     }
 
     private void OnMultiFaceLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProtoList(NormalizedLandmarkList.Parser);
       _multiFaceLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnFaceRectsFromLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProtoList(NormalizedRect.Parser);
       _faceRectsFromLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnFaceRectsFromDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProtoList(NormalizedRect.Parser);
       _faceRectsFromDetectionsAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationGraph.cs
index 509c7610e..4a2e99252 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationGraph.cs	
@@ -15,7 +15,7 @@ public class HairSegmentationGraph : GraphRunner
   {
     public event EventHandler<OutputStream.OutputEventArgs> OnHairMaskOutput
     {
-      add => _hairMaskStream.AddListener(value);
+      add => _hairMaskStream.AddListener(value, timeoutMicrosec);
       remove => _hairMaskStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationSolution.cs
index 83a6b19ab..ad0b4e17f 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Hair Segmentation/HairSegmentationSolution.cs	
@@ -41,7 +41,7 @@ protected override IEnumerator WaitForNextValue()
     private void OnHairMaskOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetImageFrame();
+      var value = packet == null ? default : packet.GetImageFrame();
       _hairMaskAnnotationController.DrawLater(value);
       value?.Dispose();
     }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingGraph.cs
index fda30a0e5..405188efb 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingGraph.cs	
@@ -63,37 +63,37 @@ public float minTrackingConfidence
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPalmDetectectionsOutput
     {
-      add => _palmDetectionsStream.AddListener(value);
+      add => _palmDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _palmDetectionsStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnHandRectsFromPalmDetectionsOutput
     {
-      add => _handRectsFromPalmDetectionsStream.AddListener(value);
+      add => _handRectsFromPalmDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _handRectsFromPalmDetectionsStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnHandLandmarksOutput
     {
-      add => _handLandmarksStream.AddListener(value);
+      add => _handLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _handLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnHandWorldLandmarksOutput
     {
-      add => _handWorldLandmarksStream.AddListener(value);
+      add => _handWorldLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _handWorldLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnHandRectsFromLandmarksOutput
     {
-      add => _handRectsFromLandmarksStream.AddListener(value);
+      add => _handRectsFromLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _handRectsFromLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnHandednessOutput
     {
-      add => _handednessStream.AddListener(value);
+      add => _handednessStream.AddListener(value, timeoutMicrosec);
       remove => _handednessStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingSolution.cs
index f88346a26..858fac332 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Hand Tracking/HandTrackingSolution.cs	
@@ -5,7 +5,6 @@
 // https://opensource.org/licenses/MIT.
 
 using System.Collections;
-using System.Collections.Generic;
 using UnityEngine;
 
 namespace Mediapipe.Unity.Sample.HandTracking
@@ -81,35 +80,35 @@ protected override IEnumerator WaitForNextValue()
     private void OnPalmDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(Detection.Parser);
+      var value = packet == null ? default : packet.GetProtoList(Detection.Parser);
       _palmDetectionsAnnotationController.DrawLater(value);
     }
 
     private void OnHandRectsFromPalmDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProtoList(NormalizedRect.Parser);
       _handRectsFromPalmDetectionsAnnotationController.DrawLater(value);
     }
 
     private void OnHandLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProtoList(NormalizedLandmarkList.Parser);
       _handLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnHandRectsFromLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProtoList(NormalizedRect.Parser);
       _handRectsFromLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnHandednessOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(ClassificationList.Parser);
+      var value = packet == null ? default : packet.GetProtoList(ClassificationList.Parser);
       _handLandmarksAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingGraph.cs
index 6d0b91383..624c044cd 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingGraph.cs
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingGraph.cs
@@ -71,49 +71,49 @@ public float minTrackingConfidence
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseDetectionOutput
     {
-      add => _poseDetectionStream.AddListener(value);
+      add => _poseDetectionStream.AddListener(value, timeoutMicrosec);
       remove => _poseDetectionStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseLandmarksOutput
     {
-      add => _poseLandmarksStream.AddListener(value);
+      add => _poseLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _poseLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceLandmarksOutput
     {
-      add => _faceLandmarksStream.AddListener(value);
+      add => _faceLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _faceLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnLeftHandLandmarksOutput
     {
-      add => _leftHandLandmarksStream.AddListener(value);
+      add => _leftHandLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _leftHandLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnRightHandLandmarksOutput
     {
-      add => _rightHandLandmarksStream.AddListener(value);
+      add => _rightHandLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _rightHandLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseWorldLandmarksOutput
     {
-      add => _poseWorldLandmarksStream.AddListener(value);
+      add => _poseWorldLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _poseWorldLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnSegmentationMaskOutput
     {
-      add => _segmentationMaskStream.AddListener(value);
+      add => _segmentationMaskStream.AddListener(value, timeoutMicrosec);
       remove => _segmentationMaskStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseRoiOutput
     {
-      add => _poseRoiStream.AddListener(value);
+      add => _poseRoiStream.AddListener(value, timeoutMicrosec);
       remove => _poseRoiStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingSolution.cs
index ac5defc60..d362b2de3 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingSolution.cs
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Holistic/HolisticTrackingSolution.cs
@@ -112,49 +112,49 @@ protected override IEnumerator WaitForNextValue()
     private void OnPoseDetectionOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(Detection.Parser);
+      var value = packet == null ? default : packet.GetProto(Detection.Parser);
       _poseDetectionAnnotationController.DrawLater(value);
     }
 
     private void OnFaceLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedLandmarkList.Parser);
       _holisticAnnotationController.DrawFaceLandmarkListLater(value);
     }
 
     private void OnPoseLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedLandmarkList.Parser);
       _holisticAnnotationController.DrawPoseLandmarkListLater(value);
     }
 
     private void OnLeftHandLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedLandmarkList.Parser);
       _holisticAnnotationController.DrawLeftHandLandmarkListLater(value);
     }
 
     private void OnRightHandLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedLandmarkList.Parser);
       _holisticAnnotationController.DrawRightHandLandmarkListLater(value);
     }
 
     private void OnPoseWorldLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(LandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(LandmarkList.Parser);
       _poseWorldLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnSegmentationMaskOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetImageFrame();
+      var value = packet == null ? default : packet.GetImageFrame();
       _segmentationMaskAnnotationController.DrawLater(value);
       value?.Dispose();
     }
@@ -162,7 +162,7 @@ private void OnSegmentationMaskOutput(object stream, OutputStream.OutputEventArg
     private void OnPoseRoiOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedRect.Parser);
       _poseRoiAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingGraph.cs
index b418efa66..ae407438d 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingGraph.cs	
@@ -28,19 +28,19 @@ public class IrisTrackingGraph : GraphRunner
   {
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceDetectionsOutput
     {
-      add => _faceDetectionsStream.AddListener(value);
+      add => _faceDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _faceDetectionsStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceRectOutput
     {
-      add => _faceRectStream.AddListener(value);
+      add => _faceRectStream.AddListener(value, timeoutMicrosec);
       remove => _faceRectStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnFaceLandmarksWithIrisOutput
     {
-      add => _faceLandmarksWithIrisStream.AddListener(value);
+      add => _faceLandmarksWithIrisStream.AddListener(value, timeoutMicrosec);
       remove => _faceLandmarksWithIrisStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingSolution.cs
index 6584187d1..17d591105 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Iris Tracking/IrisTrackingSolution.cs	
@@ -49,21 +49,21 @@ protected override IEnumerator WaitForNextValue()
     private void OnFaceDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(Detection.Parser);
+      var value = packet == null ? default : packet.GetProtoList(Detection.Parser);
       _faceDetectionsAnnotationController.DrawLater(value);
     }
 
     private void OnFaceRectOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedRect.Parser);
       _faceRectAnnotationController.DrawLater(value);
     }
 
     private void OnFaceLandmarksWithIrisOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedLandmarkList.Parser);
       _faceLandmarksWithIrisAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/MediaPipe Video/MediaPipeVideoGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/MediaPipe Video/MediaPipeVideoGraph.cs
index c13ad861e..d9c1207f0 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/MediaPipe Video/MediaPipeVideoGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/MediaPipe Video/MediaPipeVideoGraph.cs	
@@ -18,7 +18,7 @@ public class MediaPipeVideoGraph : GraphRunner
 
     public event EventHandler<OutputStream.OutputEventArgs> OnOutput
     {
-      add => _outputVideoStream.AddListener(value);
+      add => _outputVideoStream.AddListener(value, timeoutMicrosec);
       remove => _outputVideoStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionGraph.cs
index e650160b0..c07bd8445 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionGraph.cs	
@@ -14,7 +14,7 @@ public class ObjectDetectionGraph : GraphRunner
   {
     public event EventHandler<OutputStream.OutputEventArgs> OnOutputDetectionsOutput
     {
-      add => _outputDetectionsStream.AddListener(value);
+      add => _outputDetectionsStream.AddListener(value, timeoutMicrosec);
       remove => _outputDetectionsStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionSolution.cs
index bb56ab074..e310e1829 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Object Detection/ObjectDetectionSolution.cs	
@@ -39,7 +39,7 @@ protected override IEnumerator WaitForNextValue()
     private void OnOutputDetectionsOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProtoList(Detection.Parser);
+      var value = packet == null ? default : packet.GetProtoList(Detection.Parser);
       _outputDetectionsAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingGraph.cs
index f5605b858..f017561f0 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingGraph.cs	
@@ -62,31 +62,31 @@ public float minTrackingConfidence
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseDetectionOutput
     {
-      add => _poseDetectionStream.AddListener(value);
+      add => _poseDetectionStream.AddListener(value, timeoutMicrosec);
       remove => _poseDetectionStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseLandmarksOutput
     {
-      add => _poseLandmarksStream.AddListener(value);
+      add => _poseLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _poseLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnPoseWorldLandmarksOutput
     {
-      add => _poseWorldLandmarksStream.AddListener(value);
+      add => _poseWorldLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _poseWorldLandmarksStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnSegmentationMaskOutput
     {
-      add => _segmentationMaskStream.AddListener(value);
+      add => _segmentationMaskStream.AddListener(value, timeoutMicrosec);
       remove => _segmentationMaskStream.RemoveListener(value);
     }
 
     public event EventHandler<OutputStream.OutputEventArgs> OnRoiFromLandmarksOutput
     {
-      add => _roiFromLandmarksStream.AddListener(value);
+      add => _roiFromLandmarksStream.AddListener(value, timeoutMicrosec);
       remove => _roiFromLandmarksStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingSolution.cs
index be7ddc2db..ed16844a2 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Pose Tracking/PoseTrackingSolution.cs	
@@ -103,28 +103,28 @@ protected override IEnumerator WaitForNextValue()
     private void OnPoseDetectionOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(Detection.Parser);
+      var value = packet == null ? default : packet.GetProto(Detection.Parser);
       _poseDetectionAnnotationController.DrawLater(value);
     }
 
     private void OnPoseLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedLandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedLandmarkList.Parser);
       _poseLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnPoseWorldLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(LandmarkList.Parser);
+      var value = packet == null ? default : packet.GetProto(LandmarkList.Parser);
       _poseWorldLandmarksAnnotationController.DrawLater(value);
     }
 
     private void OnSegmentationMaskOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetImageFrame();
+      var value = packet == null ? default : packet.GetImageFrame();
       _segmentationMaskAnnotationController.DrawLater(value);
       value?.Dispose();
     }
@@ -132,7 +132,7 @@ private void OnSegmentationMaskOutput(object stream, OutputStream.OutputEventArg
     private void OnRoiFromLandmarksOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetProto(NormalizedRect.Parser);
+      var value = packet == null ? default : packet.GetProto(NormalizedRect.Parser);
       _roiFromLandmarksAnnotationController.DrawLater(value);
     }
   }
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationGraph.cs b/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationGraph.cs
index 80b1dd57e..b94ff1f2a 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationGraph.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationGraph.cs	
@@ -15,7 +15,7 @@ public class SelfieSegmentationGraph : GraphRunner
   {
     public event EventHandler<OutputStream.OutputEventArgs> OnSegmentationMaskOutput
     {
-      add => _segmentationMaskStream.AddListener(value);
+      add => _segmentationMaskStream.AddListener(value, timeoutMicrosec);
       remove => _segmentationMaskStream.RemoveListener(value);
     }
 
diff --git a/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationSolution.cs b/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationSolution.cs
index 814684a92..bff564817 100644
--- a/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationSolution.cs	
+++ b/Assets/MediaPipeUnity/Samples/Scenes/Selfie Segmentation/SelfieSegmentationSolution.cs	
@@ -42,7 +42,7 @@ protected override IEnumerator WaitForNextValue()
     private void OnSegmentationMaskOutput(object stream, OutputStream.OutputEventArgs eventArgs)
     {
       var packet = eventArgs.packet;
-      var value = packet.IsEmpty() ? default : packet.GetImageFrame();
+      var value = packet == null ? default : packet.GetImageFrame();
       _segmentationMaskAnnotationController.DrawLater(value);
       value?.Dispose();
     }
diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
index d1bb9a400..b0607784c 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
@@ -24,11 +24,17 @@ public sealed class OutputStream : IDisposable
   {
     public readonly struct OutputEventArgs
     {
+      /// <summary>
+      ///   <see cref="Packet"/> that contains the output value.
+      ///   <see langword="null"/> if there's no output.
+      /// </summary>
       public readonly Packet packet;
+      public readonly long timestampMicrosecond;
 
-      public OutputEventArgs(Packet packet)
+      internal OutputEventArgs(Packet packet, long timestampMicrosecond)
       {
         this.packet = packet;
+        this.timestampMicrosecond = timestampMicrosecond;
       }
     }
 
@@ -80,6 +86,7 @@ private Packet outputPacket
     private Task<NextResult> _waitTask;
 
     private event EventHandler<OutputEventArgs> OnReceived;
+    private long _lastTimestampMicrosec;
 
     private Packet _referencePacket;
     private Packet referencePacket
@@ -196,7 +203,23 @@ public void StartPolling()
       _poller = _calculatorGraph.AddOutputStreamPoller(streamName, observeTimestampBounds);
     }
 
-    public void AddListener(EventHandler<OutputEventArgs> callback)
+    /// <summary>
+    /// </summary>
+    /// <remarks>
+    ///   When <see cref="observeTimestampBounds" /> is set to <see langword="true"/>, <see cref="callback"/> can be invoked with an empty packet.
+    ///   However, in some cases, most of the output packets can be empty even if the output must be present.<br/>
+    ///   In that case, specify <paramref name="emptyPacketThresholdMicrosecond" /> to mitigate the problem.
+    /// </remarks>
+    /// <param name="callback"></param>
+    /// <param name="emptyPacketThresholdMicrosecond">
+    ///   When <see cref="observeTimestampBounds" /> is set to <see langword="true"/>, <see cref="callback"/> can be invoked with an empty packet.
+    ///   However, in some cases, most of the output packets can be empty even if the output must be present.<br/>
+    ///
+    ///   This parameter specifies the duration for ignoring empty packets.
+    ///   That is, when receiving an empty packet, <paramref name="callback"/> will not be invoked
+    ///   unless the specified time has elapsed since the last non-empty output was received.
+    /// </param>
+    public void AddListener(EventHandler<OutputEventArgs> callback, long emptyPacketThresholdMicrosecond = 0)
     {
       ThrowIfDisposed();
 
@@ -204,7 +227,22 @@ public void AddListener(EventHandler<OutputEventArgs> callback)
       {
         _calculatorGraph.ObserveOutputStream(streamName, _id, InvokeIfOutputStreamFound, observeTimestampBounds);
       }
-      OnReceived += callback;
+
+      if (emptyPacketThresholdMicrosecond <= 0)
+      {
+        OnReceived += callback;
+        return;
+      }
+
+      OnReceived += (sender, eventArgs) =>
+      {
+        var stream = (OutputStream)sender;
+        if (eventArgs.packet == null && eventArgs.timestampMicrosecond - stream._lastTimestampMicrosec <= emptyPacketThresholdMicrosecond)
+        {
+          return;
+        }
+        callback(stream, eventArgs);
+      };
     }
 
     public void RemoveListener(EventHandler<OutputEventArgs> eventHandler)
@@ -338,7 +376,14 @@ private void ClearWaitTask()
 
     private void InvokeOnReceived(Packet nextPacket)
     {
-      OnReceived?.Invoke(this, new OutputEventArgs(nextPacket));
+      var isEmpty = nextPacket.IsEmpty();
+      var timestampMicrosec = nextPacket.TimestampMicroseconds();
+      if (!isEmpty)
+      {
+        // not thread-safe
+        _lastTimestampMicrosec = Math.Max(timestampMicrosec, _lastTimestampMicrosec);
+      }
+      OnReceived?.Invoke(this, new OutputEventArgs(isEmpty ? null : nextPacket, timestampMicrosec));
     }
 
     private void ThrowIfDisposed()
@@ -366,9 +411,7 @@ private static StatusArgs InvokeIfOutputStreamFound(IntPtr graphPtr, int streamI
 
         var packet = outputStream.referencePacket;
         packet.SwitchNativePtr(packetPtr);
-
         outputStream.InvokeOnReceived(packet);
-
         packet.ReleaseMpResource();
 
         return StatusArgs.Ok();