diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/External/Protobuf.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/External/Protobuf.cs
index c146096f7..b8c2e4011 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/External/Protobuf.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/External/Protobuf.cs
@@ -1,9 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.Runtime.InteropServices;
-
-using pb = global::Google.Protobuf;
-
 namespace Mediapipe {
   internal static class Protobuf {
     static Protobuf() {
diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Packet/StringPacket.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Packet/StringPacket.cs
index e75a46e66..afe247c82 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Packet/StringPacket.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Packet/StringPacket.cs
@@ -34,7 +34,7 @@ public override string Get() {
     }
 
     public byte[] GetByteArray() {
-      UnsafeNativeMethods.mp_Packet__GetByteString(mpPtr, out var strPtr, out int size);
+      UnsafeNativeMethods.mp_Packet__GetByteString(mpPtr, out var strPtr, out int size).Assert();
       GC.KeepAlive(this);
 
       var bytes = new byte[size];
diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Timestamp.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Timestamp.cs
index a7bc774c4..7051004de 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Timestamp.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Framework/Timestamp.cs
@@ -5,7 +5,7 @@ public class Timestamp : MpResourceHandle, IEquatable<Timestamp> {
     public Timestamp(IntPtr ptr) : base(ptr) {}
 
     public Timestamp(Int64 value) : base() {
-      UnsafeNativeMethods.mp_Timestamp__l(value, out var ptr);
+      UnsafeNativeMethods.mp_Timestamp__l(value, out var ptr).Assert();
       this.ptr = ptr;
     }
 
diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/PInvoke/NativeMethods/External/Glog_Unsafe.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/PInvoke/NativeMethods/External/Glog_Unsafe.cs
index f43ed8295..12f6164d9 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/PInvoke/NativeMethods/External/Glog_Unsafe.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/PInvoke/NativeMethods/External/Glog_Unsafe.cs
@@ -9,33 +9,33 @@ internal static partial class UnsafeNativeMethods {
     public static extern MpReturnCode google_ShutdownGoogleLogging();
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_FLAGS_logtostderr([MarshalAs(UnmanagedType.I1)] bool value);
+    public static extern void glog_FLAGS_logtostderr([MarshalAs(UnmanagedType.I1)] bool value);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_FLAGS_stderrthreshold(int threshold);
+    public static extern void glog_FLAGS_stderrthreshold(int threshold);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_FLAGS_minloglevel(int level);
+    public static extern void glog_FLAGS_minloglevel(int level);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_FLAGS_log_dir(string dir);
+    public static extern void glog_FLAGS_log_dir(string dir);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_FLAGS_v(int v);
+    public static extern void glog_FLAGS_v(int v);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_LOG_INFO__PKc(string str);
+    public static extern void glog_LOG_INFO__PKc(string str);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_LOG_WARNING__PKc(string str);
+    public static extern void glog_LOG_WARNING__PKc(string str);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_LOG_ERROR__PKc(string str);
+    public static extern void glog_LOG_ERROR__PKc(string str);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode glog_LOG_FATAL__PKc(string str);
+    public static extern void glog_LOG_FATAL__PKc(string str);
 
     [DllImport (MediaPipeLibrary, ExactSpelling = true)]
-    public static extern MpReturnCode google_FlushLogFiles(Glog.Severity severity);
+    public static extern void google_FlushLogFiles(Glog.Severity severity);
   }
 }