feat: yt-dlp prefers H.264, falls back to built-in, no pipe hang (v1.0.0.13)

- Format string prefers avc1 video + m4a audio, then any codec. The RTX 2070
  host can hardware-transcode H.264 but not AV1.
- Pass Jellyfin's ffmpeg via --ffmpeg-location instead of relying on PATH.
- If yt-dlp fails, retry with the built-in YoutubeExplode downloader.
- Read stdout/stderr while yt-dlp runs (and add --no-progress); before,
  stdout was never read, so a full pipe buffer could block yt-dlp forever.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Jellyfin.Plugin.CinemaTrailers4Jellyfins/Jellyfin.Plugin.CinemaTrailers4Jellyfins.csproj

@@ -3,8 +3,8 @@
   <PropertyGroup>
     <TargetFramework>net9.0</TargetFramework>
     <RootNamespace>Jellyfin.Plugin.CinemaTrailers4Jellyfins</RootNamespace>
-    <AssemblyVersion>1.0.0.12</AssemblyVersion>
-    <FileVersion>1.0.0.12</FileVersion>
+    <AssemblyVersion>1.0.0.13</AssemblyVersion>
+    <FileVersion>1.0.0.13</FileVersion>
     <Nullable>enable</Nullable>
     <GenerateDocumentationFile>false</GenerateDocumentationFile>
     <TreatWarningsAsErrors>false</TreatWarningsAsErrors>

Jellyfin.Plugin.CinemaTrailers4Jellyfins/Services/TrailerDownloadService.cs

@@ -63,8 +63,10 @@ namespace Jellyfin.Plugin.CinemaTrailers4Jellyfins.Services
 
             if (!string.IsNullOrWhiteSpace(ytDlpPath) && File.Exists(ytDlpPath))
             {
-                return await DownloadWithYtDlpAsync(youtubeKey, outputPath, preferredHeight, ytDlpPath, ct)
-                    .ConfigureAwait(false);
+                if (await DownloadWithYtDlpAsync(youtubeKey, outputPath, preferredHeight, ytDlpPath, ct).ConfigureAwait(false))
+                    return true;
+
+                _logger.LogWarning("|CinemaTrailers4Jellyfins| yt-dlp failed for {Key}; falling back to the built-in downloader.", youtubeKey);
             }
 
             return await DownloadWithYoutubeExplodeAsync(youtubeKey, outputPath, preferredHeight, ct)
@@ -224,13 +226,16 @@ namespace Jellyfin.Plugin.CinemaTrailers4Jellyfins.Services
         {
             try
             {
-                // Format selects the best video at or below preferredHeight merged with the best audio.
-                // --merge-output-format mp4 ensures the output is always an mp4.
+                // Format selects the best video at or below preferredHeight merged with the best audio,
+                // preferring H.264 + AAC (plays or hardware-transcodes on every client; VP9/AV1 often
+                // need a CPU transcode). --merge-output-format mp4 ensures the output is always an mp4.
                 var args = string.Join(" ",
-                    $"-f \"bestvideo[height<={preferredHeight}]+bestaudio/best[height<={preferredHeight}]\"",
+                    $"-f \"bestvideo[height<={preferredHeight}][vcodec^=avc1]+bestaudio[ext=m4a]/bestvideo[height<={preferredHeight}]+bestaudio/best[height<={preferredHeight}]\"",
                     "--merge-output-format mp4",
                     "--no-playlist",
                     "--no-warnings",
+                    "--no-progress",
+                    $"--ffmpeg-location \"{FfmpegLocator.Path}\"",
                     $"-o \"{outputPath}\"",
                     $"\"https://www.youtube.com/watch?v={key}\"");
 
@@ -252,11 +257,15 @@ namespace Jellyfin.Plugin.CinemaTrailers4Jellyfins.Services
                 };
 
                 process.Start();
+                // Drain both pipes while yt-dlp runs so a full buffer can never block it.
+                var stdoutTask = process.StandardOutput.ReadToEndAsync(ct);
+                var stderrTask = process.StandardError.ReadToEndAsync(ct);
                 await process.WaitForExitAsync(ct).ConfigureAwait(false);
+                await stdoutTask.ConfigureAwait(false);
+                var stderr = await stderrTask.ConfigureAwait(false);
 
                 if (process.ExitCode != 0)
                 {
-                    var stderr = await process.StandardError.ReadToEndAsync(ct).ConfigureAwait(false);
                     _logger.LogError("|CinemaTrailers4Jellyfins| yt-dlp exited with code {Code} for {Key}: {Error}",
                         process.ExitCode, key, stderr);
                     return false;

build.yaml

@@ -1,5 +1,5 @@
 ---
-version: 1.0.0.12
+version: 1.0.0.13
 name: CinemaTrailers4Jellyfins
 guid: b581493e-1046-40ed-b6dc-cb8027624984
 description: >
@@ -12,12 +12,12 @@ category: General
 owner: 514mart
 targetAbi: 10.11.0.0
 changelog:
-  - Anime trailers now only play before anime. Western animation (Pixar,
-    Disney, ...) is no longer blocked and follows the normal genre filter
-    again. A trailer counts as anime when TMDB tags it "anime" or "based on
-    manga", or it is animation in Japanese, Chinese or Korean; it is marked
-    with a ct4j-anime tag in its NFO at download time. Your anime is
-    recognised by the "Anime" genre or the same TMDB keywords
+  - yt-dlp now prefers H.264 + AAC (plays or hardware-transcodes on every
+    client; VP9/AV1 often needed a CPU transcode) and uses Jellyfin's own
+    ffmpeg for the merge
+  - If yt-dlp fails, the built-in downloader is tried instead
+  - Fix a possible hang: yt-dlp's output is now read while it runs, so a
+    full output buffer can no longer block it
 
 dotnetProjects:
   - name: Jellyfin.Plugin.CinemaTrailers4Jellyfins