windows nvidia h264 workaround (#1487)

* work around bad h264_cuvid behavior on windows with ffmpeg snapshot

* use latest ffmpeg build on windows

* nvdec => cuda

.github/workflows/artifacts.yml

@@ -208,7 +208,7 @@ jobs:
         id: downloadffmpeg
         name: Download ffmpeg
         with:
-          url: "https://github.com/GyanD/codexffmpeg/releases/download/2023-10-04-git-9078dc0c52/ffmpeg-2023-10-04-git-9078dc0c52-full_build.7z"
+          url: "https://github.com/GyanD/codexffmpeg/releases/download/2023-10-16-git-5ddab49d48/ffmpeg-2023-10-16-git-5ddab49d48-full_build.7z"
           target: ffmpeg/
 
       - name: Build

ErsatzTV.FFmpeg/Decoder/Cuvid/DecoderImplicitCuda.cs

@@ -0,0 +1,13 @@
+namespace ErsatzTV.FFmpeg.Decoder.Cuvid;
+
+public class DecoderImplicitCuda : DecoderBase
+{
+    protected override FrameDataLocation OutputFrameDataLocation => FrameDataLocation.Hardware;
+    public override string Name => string.Empty;
+    public override IList<string> InputOptions(InputFile inputFile) =>
+        new List<string>
+        {
+            "-hwaccel_output_format",
+            "cuda"
+        };
+}

ErsatzTV.FFmpeg/Encoder/Nvenc/EncoderHevcNvenc.cs

@@ -19,7 +19,7 @@ public class EncoderHevcNvenc : EncoderBase
     public override StreamKind Kind => StreamKind.Video;
 
     public override IList<string> OutputOptions =>
-        new[] { "-c:v", "hevc_nvenc", "-b_ref_mode", _bFrames ? "1" : "0" };
+        new[] { "-c:v", "hevc_nvenc", "-tag:v", "hvc1", "-b_ref_mode", _bFrames ? "1" : "0" };
 
     public override FrameState NextState(FrameState currentState) => currentState with
     {

ErsatzTV.FFmpeg/Pipeline/NvidiaPipelineBuilder.cs

@@ -51,11 +51,6 @@ public class NvidiaPipelineBuilder : SoftwarePipelineBuilder
         _logger = logger;
     }
 
-    protected override bool IsNvidiaOnWindows(FFmpegState ffmpegState) =>
-        _runtimeInfo.IsOSPlatform(OSPlatform.Windows) &&
-        (ffmpegState.EncoderHardwareAccelerationMode is HardwareAccelerationMode.Nvenc ||
-         ffmpegState.DecoderHardwareAccelerationMode is HardwareAccelerationMode.Nvenc);
-
     protected override FFmpegState SetAccelState(
         VideoStream videoStream,
         FFmpegState ffmpegState,
@@ -101,6 +96,13 @@ public class NvidiaPipelineBuilder : SoftwarePipelineBuilder
         FFmpegState ffmpegState,
         PipelineContext context)
     {
+        if (NeedsCudaWorkaround(ffmpegState, videoStream.Codec))
+        {
+            var cuda = new DecoderImplicitCuda();
+            videoInputFile.AddOption(cuda);
+            return cuda;
+        }
+
         Option<IDecoder> maybeDecoder = (ffmpegState.DecoderHardwareAccelerationMode, videoStream.Codec) switch
         {
             (HardwareAccelerationMode.Nvenc, VideoFormat.Hevc) => new DecoderHevcCuvid(HardwareAccelerationMode.Nvenc),
@@ -645,4 +647,15 @@ public class NvidiaPipelineBuilder : SoftwarePipelineBuilder
 
         return currentState;
     }
+    
+    // the combination of:
+    // - windows
+    // - ffmpeg 6.1 snapshot (where readrate_initial_burst option is present)
+    // - h264_cuvid
+    // appears to cause jitter, so use implicit cuda decoder in that specific case
+    private bool NeedsCudaWorkaround(FFmpegState ffmpegState, string videoFormat) =>
+        _runtimeInfo.IsOSPlatform(OSPlatform.Windows)
+        && _ffmpegCapabilities.HasOption(FFmpegKnownOption.ReadrateInitialBurst)
+        && ffmpegState.DecoderHardwareAccelerationMode is HardwareAccelerationMode.Nvenc
+        && videoFormat == VideoFormat.H264;
 }

ErsatzTV.FFmpeg/Pipeline/PipelineBuilderBase.cs

@@ -1,5 +1,4 @@
 using System.Diagnostics;
-using System.Runtime.InteropServices;
 using ErsatzTV.FFmpeg.Capabilities;
 using ErsatzTV.FFmpeg.Decoder;
 using ErsatzTV.FFmpeg.Encoder;
@@ -12,7 +11,6 @@ using ErsatzTV.FFmpeg.OutputFormat;
 using ErsatzTV.FFmpeg.OutputOption;
 using ErsatzTV.FFmpeg.OutputOption.Metadata;
 using ErsatzTV.FFmpeg.Protocol;
-using ErsatzTV.FFmpeg.Runtime;
 using Microsoft.Extensions.Logging;
 
 namespace ErsatzTV.FFmpeg.Pipeline;
@@ -404,7 +402,6 @@ public abstract class PipelineBuilderBase : IPipelineBuilder
     }
 
     protected abstract bool IsIntelVaapiOrQsv(FFmpegState ffmpegState);
-    protected abstract bool IsNvidiaOnWindows(FFmpegState ffmpegState);
 
     protected abstract FFmpegState SetAccelState(
         VideoStream videoStream,
@@ -643,13 +640,6 @@ public abstract class PipelineBuilderBase : IPipelineBuilder
             };
         }
 
-        // TODO: when ffmpeg/nvenc stops being weird on windows, remove this workaround
-        if (IsNvidiaOnWindows(ffmpegState))
-        {
-            // disable initial burst
-            initialBurst = 0;
-        }
-
         _audioInputFile.Iter(a => a.AddOption(new ReadrateInputOption(_ffmpegCapabilities, initialBurst, _logger)));
         videoInputFile.AddOption(new ReadrateInputOption(_ffmpegCapabilities, initialBurst, _logger));
     }

ErsatzTV.FFmpeg/Pipeline/SoftwarePipelineBuilder.cs

@@ -37,8 +37,6 @@ public class SoftwarePipelineBuilder : PipelineBuilderBase
 
     protected override bool IsIntelVaapiOrQsv(FFmpegState ffmpegState) => false;
 
-    protected override bool IsNvidiaOnWindows(FFmpegState ffmpegState) => false;
-
     protected override FFmpegState SetAccelState(
         VideoStream videoStream,
         FFmpegState ffmpegState,

ErsatzTV.sln.DotSettings

@@ -53,11 +53,13 @@
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=muxdelay/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=muxpreload/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=nostats/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=nvdec/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=Pixfmt/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=playout/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=Playouts/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=probesize/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=Radeon/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/UserDictionary/Words/=readrate/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=Segmenter/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=setsar/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/UserDictionary/Words/=showtitle/@EntryIndexedValue">True</s:Boolean>