diff --git a/FFMpegCore.Test/ArgumentBuilderTest.cs b/FFMpegCore.Test/ArgumentBuilderTest.cs
index 6c79d98..f4dbfe9 100644
--- a/FFMpegCore.Test/ArgumentBuilderTest.cs
+++ b/FFMpegCore.Test/ArgumentBuilderTest.cs
@@ -2,7 +2,6 @@
 using System;
 using FFMpegCore.Arguments;
 using FFMpegCore.Enums;
-using FFMpegCore.Exceptions;
 
 namespace FFMpegCore.Test
 {
diff --git a/FFMpegCore/FFMpeg/Arguments/ConcatArgument.cs b/FFMpegCore/FFMpeg/Arguments/ConcatArgument.cs
index d43988f..9c6ffa2 100644
--- a/FFMpegCore/FFMpeg/Arguments/ConcatArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/ConcatArgument.cs
@@ -18,7 +18,7 @@ public ConcatArgument(IEnumerable<string> values)
         }
 
         public void Pre() { }
-        public Task During(CancellationToken? cancellationToken = null) => Task.CompletedTask;
+        public Task During(CancellationToken cancellationToken = default) => Task.CompletedTask;
         public void Post() { }
         
         public string Text => $"-i \"concat:{string.Join(@"|", Values)}\"";
diff --git a/FFMpegCore/FFMpeg/Arguments/DemuxConcatArgument.cs b/FFMpegCore/FFMpeg/Arguments/DemuxConcatArgument.cs
index e915c77..5651802 100644
--- a/FFMpegCore/FFMpeg/Arguments/DemuxConcatArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/DemuxConcatArgument.cs
@@ -21,7 +21,7 @@ public DemuxConcatArgument(IEnumerable<string> values)
         private readonly string _tempFileName = Path.Combine(FFMpegOptions.Options.TempDirectory, Guid.NewGuid() + ".txt");
 
         public void Pre() => File.WriteAllLines(_tempFileName, Values);
-        public Task During(CancellationToken? cancellationToken = null) => Task.CompletedTask;
+        public Task During(CancellationToken cancellationToken = default) => Task.CompletedTask;
         public void Post() => File.Delete(_tempFileName);
 
         public string Text => $"-f concat -safe 0 -i \"{_tempFileName}\"";
diff --git a/FFMpegCore/FFMpeg/Arguments/IInputOutputArgument.cs b/FFMpegCore/FFMpeg/Arguments/IInputOutputArgument.cs
index 6998d5c..99def82 100644
--- a/FFMpegCore/FFMpeg/Arguments/IInputOutputArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/IInputOutputArgument.cs
@@ -6,7 +6,7 @@ namespace FFMpegCore.Arguments
     public interface IInputOutputArgument : IArgument
     {
         void Pre();
-        Task During(CancellationToken? cancellationToken = null);
+        Task During(CancellationToken cancellationToken = default);
         void Post();
     }
 }
\ No newline at end of file
diff --git a/FFMpegCore/FFMpeg/Arguments/InputArgument.cs b/FFMpegCore/FFMpeg/Arguments/InputArgument.cs
index 0ec3cd9..68c34b4 100644
--- a/FFMpegCore/FFMpeg/Arguments/InputArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/InputArgument.cs
@@ -1,5 +1,4 @@
-using System;
-using System.IO;
+using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -27,7 +26,7 @@ public void Pre()
                 throw new FileNotFoundException("Input file not found", FilePath);
         }
 
-        public Task During(CancellationToken? cancellationToken = null) => Task.CompletedTask;
+        public Task During(CancellationToken cancellationToken = default) => Task.CompletedTask;
         public void Post() { }
         
         public string Text => $"-i \"{FilePath}\"";
diff --git a/FFMpegCore/FFMpeg/Arguments/InputPipeArgument.cs b/FFMpegCore/FFMpeg/Arguments/InputPipeArgument.cs
index 990995a..17d0372 100644
--- a/FFMpegCore/FFMpeg/Arguments/InputPipeArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/InputPipeArgument.cs
@@ -19,7 +19,7 @@ public InputPipeArgument(IPipeSource writer) : base(PipeDirection.Out)
 
         public override string Text => $"-y {Writer.GetFormat()} -i \"{PipePath}\"";
 
-        public override async Task ProcessDataAsync(CancellationToken token)
+        protected override async Task ProcessDataAsync(CancellationToken token)
         {
             await Pipe.WaitForConnectionAsync(token).ConfigureAwait(false);
             if (!Pipe.IsConnected)
diff --git a/FFMpegCore/FFMpeg/Arguments/OutputArgument.cs b/FFMpegCore/FFMpeg/Arguments/OutputArgument.cs
index ec9db7c..c2aad38 100644
--- a/FFMpegCore/FFMpeg/Arguments/OutputArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/OutputArgument.cs
@@ -25,7 +25,7 @@ public void Pre()
             if (!Overwrite && File.Exists(Path))
                 throw new FFMpegException(FFMpegExceptionType.File, "Output file already exists and overwrite is disabled");
         }
-        public Task During(CancellationToken? cancellationToken = null) => Task.CompletedTask;
+        public Task During(CancellationToken cancellationToken = default) => Task.CompletedTask;
         public void Post()
         {
         }
diff --git a/FFMpegCore/FFMpeg/Arguments/OutputPipeArgument.cs b/FFMpegCore/FFMpeg/Arguments/OutputPipeArgument.cs
index f762752..ebf1e7f 100644
--- a/FFMpegCore/FFMpeg/Arguments/OutputPipeArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/OutputPipeArgument.cs
@@ -16,7 +16,7 @@ public OutputPipeArgument(IPipeSink reader) : base(PipeDirection.In)
 
         public override string Text => $"\"{PipePath}\" -y";
 
-        public override async Task ProcessDataAsync(CancellationToken token)
+        protected override async Task ProcessDataAsync(CancellationToken token)
         {
             await Pipe.WaitForConnectionAsync(token).ConfigureAwait(false);
             if (!Pipe.IsConnected)
diff --git a/FFMpegCore/FFMpeg/Arguments/PipeArgument.cs b/FFMpegCore/FFMpeg/Arguments/PipeArgument.cs
index 77db5db..16f9674 100644
--- a/FFMpegCore/FFMpeg/Arguments/PipeArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/PipeArgument.cs
@@ -34,7 +34,7 @@ public void Post()
             Pipe = null!;
         }
 
-        public async Task During(CancellationToken? cancellationToken = null)
+        public async Task During(CancellationToken cancellationToken = default)
         {
             try
             {
@@ -46,7 +46,7 @@ public async Task During(CancellationToken? cancellationToken = null)
             Post();
         }
 
-        public abstract Task ProcessDataAsync(CancellationToken token);
+        protected abstract Task ProcessDataAsync(CancellationToken token);
         public abstract string Text { get; }
     }
 }
diff --git a/FFMpegCore/FFMpeg/FFMpegArguments.cs b/FFMpegCore/FFMpeg/FFMpegArguments.cs
index b2cffd1..44e20d2 100644
--- a/FFMpegCore/FFMpeg/FFMpegArguments.cs
+++ b/FFMpegCore/FFMpeg/FFMpegArguments.cs
@@ -67,7 +67,7 @@ internal void Pre()
             foreach (var argument in Arguments.OfType<IInputOutputArgument>())
                 argument.Pre();
         }
-        internal async Task During(CancellationToken? cancellationToken = null)
+        internal async Task During(CancellationToken cancellationToken = default)
         {
             var inputOutputArguments = Arguments.OfType<IInputOutputArgument>();
             await Task.WhenAll(inputOutputArguments.Select(io => io.During(cancellationToken))).ConfigureAwait(false);
diff --git a/FFMpegCore/FFMpeg/Pipes/PipeHelpers.cs b/FFMpegCore/FFMpeg/Pipes/PipeHelpers.cs
index cce4547..c680c3e 100644
--- a/FFMpegCore/FFMpeg/Pipes/PipeHelpers.cs
+++ b/FFMpegCore/FFMpeg/Pipes/PipeHelpers.cs
@@ -1,5 +1,4 @@
 using System;
-using System.IO;
 using System.Runtime.InteropServices;
 
 namespace FFMpegCore.Pipes
diff --git a/FFMpegCore/FFProbe/IMediaAnalysis.cs b/FFMpegCore/FFProbe/IMediaAnalysis.cs
index 04e2ae3..660d776 100644
--- a/FFMpegCore/FFProbe/IMediaAnalysis.cs
+++ b/FFMpegCore/FFProbe/IMediaAnalysis.cs
@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Text;
 
 namespace FFMpegCore
 {