From 7aff65f07b1dfaffaeed813518d02cf8c972f479 Mon Sep 17 00:00:00 2001
From: Jason Dove <jason@jasondove.me>
Date: Thu, 18 Aug 2022 14:23:51 -0500
Subject: [PATCH] explicitly copy all audio streams with hls direct (#933)

* ensure audio streams are always copied with hls direct

* update changelog
---
 CHANGELOG.md                                  |  3 +
 ErsatzTV.FFmpeg.Tests/PipelineBuilderTests.cs | 63 +++++++++++++++++++
 ErsatzTV.FFmpeg/PipelineBuilder.cs            | 10 +++
 ErsatzTV.FFmpeg/State/AudioState.cs           | 13 +++-
 4 files changed, 88 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cdbb0c7b6..14dc85682 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,9 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## [Unreleased]
+### Fixed
+- When all audio streams are selected with `HLS Direct`, explicitly copy them without transcoding
+  - This only happens when the channel does not have a `Preferred Audio Language`
 
 ## [0.6.6-beta] - 2022-08-17
 ### Fixed
diff --git a/ErsatzTV.FFmpeg.Tests/PipelineBuilderTests.cs b/ErsatzTV.FFmpeg.Tests/PipelineBuilderTests.cs
index 4ff22dfa3..fea8f86b1 100644
--- a/ErsatzTV.FFmpeg.Tests/PipelineBuilderTests.cs
+++ b/ErsatzTV.FFmpeg.Tests/PipelineBuilderTests.cs
@@ -251,6 +251,69 @@ public class PipelineGeneratorTests
             "-nostdin -hide_banner -nostats -loglevel error -fflags +genpts+discardcorrupt+igndts -i /tmp/whatever.mkv -map 0:1 -map 0:0 -muxdelay 0 -muxpreload 0 -movflags +faststart -flags cgop -sc_threshold 0 -c:v copy -c:a copy -f mpegts -mpegts_flags +initial_discontinuity pipe:1");
     }
 
+    [Test]
+    public void HlsDirect_Test_All_Audio_Streams()
+    {
+        var videoInputFile = new VideoInputFile(
+            "/tmp/whatever.mkv",
+            new List<VideoStream>
+                { new(0, VideoFormat.H264, new PixelFormatYuv420P(), new FrameSize(1920, 1080), "16:9", "24", false) });
+
+        Option<AudioInputFile> audioInputFile = Option<AudioInputFile>.None;
+
+        var desiredState = new FrameState(
+            true,
+            false,
+            VideoFormat.Copy,
+            new PixelFormatYuv420P(),
+            new FrameSize(1920, 1080),
+            new FrameSize(1920, 1080),
+            "16:9",
+            Option<int>.None,
+            2000,
+            4000,
+            90_000,
+            false);
+
+        var ffmpegState = new FFmpegState(
+            false,
+            HardwareAccelerationMode.None,
+            HardwareAccelerationMode.None,
+            Option<string>.None,
+            Option<string>.None,
+            Option<TimeSpan>.None,
+            Option<TimeSpan>.None,
+            false,
+            Option<string>.None,
+            Option<string>.None,
+            Option<string>.None,
+            OutputFormatKind.MpegTs,
+            Option<string>.None,
+            Option<string>.None,
+            0,
+            Option<int>.None);
+
+        var builder = new PipelineBuilder(
+            new DefaultHardwareCapabilities(),
+            videoInputFile,
+            audioInputFile,
+            None,
+            None,
+            "",
+            "",
+            _logger);
+        FFmpegPipeline result = builder.Build(ffmpegState, desiredState);
+
+        result.PipelineSteps.Should().HaveCountGreaterThan(0);
+        result.PipelineSteps.Should().Contain(ps => ps is EncoderCopyVideo);
+        result.PipelineSteps.Should().Contain(ps => ps is EncoderCopyAudio);
+
+        string command = PrintCommand(videoInputFile, audioInputFile, None, None, result);
+
+        command.Should().Be(
+            "-nostdin -hide_banner -nostats -loglevel error -fflags +genpts+discardcorrupt+igndts -i /tmp/whatever.mkv -map 0:a -map 0:0 -muxdelay 0 -muxpreload 0 -movflags +faststart -flags cgop -sc_threshold 0 -c:v copy -c:a copy -f mpegts -mpegts_flags +initial_discontinuity pipe:1");
+    }
+
     [Test]
     public void Resize_Image_Test()
     {
diff --git a/ErsatzTV.FFmpeg/PipelineBuilder.cs b/ErsatzTV.FFmpeg/PipelineBuilder.cs
index 5b995b2d5..4d42bbaf3 100644
--- a/ErsatzTV.FFmpeg/PipelineBuilder.cs
+++ b/ErsatzTV.FFmpeg/PipelineBuilder.cs
@@ -539,6 +539,16 @@ public class PipelineBuilder
             // TODO: if all video filters are software, use software pixel format for hwaccel output
             // might be able to skip scale_cuda=format=whatever,hwdownload,format=whatever
 
+            if (_audioInputFile.IsNone)
+            {
+                // always need to specify audio codec so ffmpeg doesn't default to a codec we don't want
+                foreach (IEncoder step in AvailableEncoders.ForAudioFormat(AudioState.Copy, _logger))
+                {
+                    currentState = step.NextState(currentState);
+                    _pipelineSteps.Add(step);
+                }
+            }
+
             foreach (AudioInputFile audioInputFile in _audioInputFile)
             {
                 // always need to specify audio codec so ffmpeg doesn't default to a codec we don't want
diff --git a/ErsatzTV.FFmpeg/State/AudioState.cs b/ErsatzTV.FFmpeg/State/AudioState.cs
index 215f49128..28265b771 100644
--- a/ErsatzTV.FFmpeg/State/AudioState.cs
+++ b/ErsatzTV.FFmpeg/State/AudioState.cs
@@ -7,4 +7,15 @@ public record AudioState(
     Option<int> AudioBufferSize,
     Option<int> AudioSampleRate,
     Option<TimeSpan> AudioDuration,
-    bool NormalizeLoudness);
+    bool NormalizeLoudness)
+{
+    public static readonly AudioState Copy = new(
+        Format.AudioFormat.Copy,
+        Option<int>.None,
+        Option<int>.None,
+        Option<int>.None,
+        Option<int>.None,
+        Option<TimeSpan>.None,
+        false
+    );
+}