Implement Filter-Before-Capture Structure

Util/FFmpeg/FFmpegProcess.cs

@@ -15,7 +15,7 @@ namespace ADOFAIRenderer.Util.FFmpeg
 
         public bool IsEnd => _ffmpegProcess is { HasExited: true };
 
-        public void Execute(string command)
+        protected void Execute(string command)
         {
             if (string.IsNullOrEmpty(command))
             {
@@ -39,7 +39,7 @@ namespace ADOFAIRenderer.Util.FFmpeg
         public void SendDataFromBuffer(byte[] buffer, int length = -1)
         {
             if (_inputStream == null) return;
-            int writeLength = length < 0 ? buffer.Length : length;
+            var writeLength = length < 0 ? buffer.Length : length;
             _inputStream.Write(buffer, 0, writeLength);
             _inputStream.Flush();
         }

Util/FrameReader.cs

@@ -1,4 +1,5 @@
-using System;
+using System;
+using System.Buffers;
 using System.Collections.Generic;
 using ADOFAIRenderer.Component;
 using ADOFAIRenderer.Util.FFmpeg;
@@ -17,6 +18,7 @@ namespace ADOFAIRenderer.Util
         private readonly Stack<ReadbackRequestState> _statePool = new Stack<ReadbackRequestState>();
         private readonly object _poolLock = new object();
         private bool _isInitialized;
+        private volatile bool _isDisposed;
         
         public FrameReader()
         {
@@ -63,7 +65,16 @@ namespace ADOFAIRenderer.Util
         {
             var frame = state.FrameIndex;
 
-            if (RenderManager.IsRenderCancelled)
+            lock (_poolLock)
+            {
+                if (_isDisposed)
+                {
+                    state.Dispose();
+                    return;
+                }
+            }
+
+            if (RenderMod.IsRenderCancelled)
             {
                 RecycleState(state);
                 return;
@@ -72,9 +83,12 @@ namespace ADOFAIRenderer.Util
             if (request.hasError)
             {
                 RenderMod.ReadbackFailureCount++;
-                Melon<RenderMod>.Logger.Warning($"[OOM Prevent] GPU Readback failed for frame {frame}. Queue deadlock prevented by sending an empty frame.");
+                Melon<RenderMod>.Logger.Warning($"[OOM Prevent] GPU Readback failed for frame {frame}. Queue deadlock prevented by sending a black frame.");
 
-                PushToQueue(frame, Array.Empty<byte>());
+                var byteSize = state.NativeBuffer.Length;
+                var blackFrame = ArrayPool<byte>.Shared.Rent(byteSize);
+                Array.Clear(blackFrame, 0, byteSize);
+                PushToQueue(frame, blackFrame);
             }
             else
             {
@@ -97,15 +111,15 @@ namespace ADOFAIRenderer.Util
 
         private void RecycleState(ReadbackRequestState state)
         {
-            if (!_isInitialized)
-            {
-                state.Dispose();
-                return;
-            }
-            
-            state.Recycle();
             lock (_poolLock)
             {
+                if (_isDisposed || !_isInitialized)
+                {
+                    state.Dispose();
+                    return;
+                }
+                
+                state.Recycle();
                 _statePool.Push(state);
             }
         }
@@ -122,6 +136,8 @@ namespace ADOFAIRenderer.Util
         {
             lock (_poolLock)
             {
+                if (_isDisposed) return;
+                _isDisposed = true;
                 while (_statePool.Count > 0)
                 {
                     var state = _statePool.Pop();