Let HLS Controller decide if subtitle should be burn in

Previously, we predicted whether the subtitle should be burned in with transcode reasons, but that was not accurate because the actual transcoding codec is only determined after the client has requested the stream. This pass through the option to the `DynamicHlsController` to handle the subtitle burn-in during the actual transcoding process. Now the client should be responsible to conditionally load the subtitle when this option is enabled.

1 files changed, 42 insertions, 21 deletions

diff --git a/Jellyfin.Api/Controllers/DynamicHlsController.cs b/Jellyfin.Api/Controllers/DynamicHlsController.cs
index db1d86698..924f010e4 100644
--- a/Jellyfin.Api/Controllers/DynamicHlsController.cs
+++ b/Jellyfin.Api/Controllers/DynamicHlsController.cs
@@ -158,6 +158,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="maxHeight">Optional. The max height.</param>
     /// <param name="enableSubtitlesInManifest">Optional. Whether to enable subtitles in the manifest.</param>
     /// <param name="enableAudioVbrEncoding">Optional. Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Hls live stream retrieved.</response>
     /// <returns>A <see cref="FileResult"/> containing the hls file.</returns>
     [HttpGet("Videos/{itemId}/live.m3u8")]
@@ -216,7 +217,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] int? maxWidth,
         [FromQuery] int? maxHeight,
         [FromQuery] bool? enableSubtitlesInManifest,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         VideoRequestDto streamingRequest = new VideoRequestDto
         {
@@ -251,7 +253,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             Height = height,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -271,7 +273,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             MaxHeight = maxHeight,
             MaxWidth = maxWidth,
             EnableSubtitlesInManifest = enableSubtitlesInManifest ?? true,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         // CTS lifecycle is managed internally.
@@ -398,6 +401,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="enableAdaptiveBitrateStreaming">Enable adaptive bitrate streaming.</param>
     /// <param name="enableTrickplay">Enable trickplay image playlists being added to master playlist.</param>
     /// <param name="enableAudioVbrEncoding">Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Video stream returned.</response>
     /// <returns>A <see cref="FileResult"/> containing the playlist file.</returns>
     [HttpGet("Videos/{itemId}/master.m3u8")]
@@ -457,7 +461,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] Dictionary<string, string> streamOptions,
         [FromQuery] bool enableAdaptiveBitrateStreaming = true,
         [FromQuery] bool enableTrickplay = true,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         var streamingRequest = new HlsVideoRequestDto
         {
@@ -493,7 +498,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             MaxHeight = maxHeight,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -512,7 +517,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             StreamOptions = streamOptions,
             EnableAdaptiveBitrateStreaming = enableAdaptiveBitrateStreaming,
             EnableTrickplay = enableTrickplay,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         return await _dynamicHlsHelper.GetMasterHlsPlaylist(TranscodingJobType, streamingRequest, enableAdaptiveBitrateStreaming).ConfigureAwait(false);
@@ -572,6 +578,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="streamOptions">Optional. The streaming options.</param>
     /// <param name="enableAdaptiveBitrateStreaming">Enable adaptive bitrate streaming.</param>
     /// <param name="enableAudioVbrEncoding">Optional. Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Audio stream returned.</response>
     /// <returns>A <see cref="FileResult"/> containing the playlist file.</returns>
     [HttpGet("Audio/{itemId}/master.m3u8")]
@@ -629,7 +636,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] EncodingContext? context,
         [FromQuery] Dictionary<string, string> streamOptions,
         [FromQuery] bool enableAdaptiveBitrateStreaming = true,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         var streamingRequest = new HlsAudioRequestDto
         {
@@ -663,7 +671,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             Height = height,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -681,7 +689,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             Context = context ?? EncodingContext.Streaming,
             StreamOptions = streamOptions,
             EnableAdaptiveBitrateStreaming = enableAdaptiveBitrateStreaming,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         return await _dynamicHlsHelper.GetMasterHlsPlaylist(TranscodingJobType, streamingRequest, enableAdaptiveBitrateStreaming).ConfigureAwait(false);
@@ -741,6 +750,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="context">Optional. The <see cref="EncodingContext"/>.</param>
     /// <param name="streamOptions">Optional. The streaming options.</param>
     /// <param name="enableAudioVbrEncoding">Optional. Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Video stream returned.</response>
     /// <returns>A <see cref="FileResult"/> containing the audio file.</returns>
     [HttpGet("Videos/{itemId}/main.m3u8")]
@@ -797,7 +807,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] int? videoStreamIndex,
         [FromQuery] EncodingContext? context,
         [FromQuery] Dictionary<string, string> streamOptions,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         using var cancellationTokenSource = new CancellationTokenSource();
         var streamingRequest = new VideoRequestDto
@@ -834,7 +845,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             MaxHeight = maxHeight,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -851,7 +862,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             VideoStreamIndex = videoStreamIndex,
             Context = context ?? EncodingContext.Streaming,
             StreamOptions = streamOptions,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         return await GetVariantPlaylistInternal(streamingRequest, cancellationTokenSource)
@@ -911,6 +923,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="context">Optional. The <see cref="EncodingContext"/>.</param>
     /// <param name="streamOptions">Optional. The streaming options.</param>
     /// <param name="enableAudioVbrEncoding">Optional. Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Audio stream returned.</response>
     /// <returns>A <see cref="FileResult"/> containing the audio file.</returns>
     [HttpGet("Audio/{itemId}/main.m3u8")]
@@ -966,7 +979,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] int? videoStreamIndex,
         [FromQuery] EncodingContext? context,
         [FromQuery] Dictionary<string, string> streamOptions,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         using var cancellationTokenSource = new CancellationTokenSource();
         var streamingRequest = new StreamingRequestDto
@@ -1001,7 +1015,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             Height = height,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -1018,7 +1032,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             VideoStreamIndex = videoStreamIndex,
             Context = context ?? EncodingContext.Streaming,
             StreamOptions = streamOptions,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         return await GetVariantPlaylistInternal(streamingRequest, cancellationTokenSource)
@@ -1084,6 +1099,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="context">Optional. The <see cref="EncodingContext"/>.</param>
     /// <param name="streamOptions">Optional. The streaming options.</param>
     /// <param name="enableAudioVbrEncoding">Optional. Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Video stream returned.</response>
     /// <returns>A <see cref="FileResult"/> containing the audio file.</returns>
     [HttpGet("Videos/{itemId}/hls1/{playlistId}/{segmentId}.{container}")]
@@ -1146,7 +1162,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] int? videoStreamIndex,
         [FromQuery] EncodingContext? context,
         [FromQuery] Dictionary<string, string> streamOptions,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         var streamingRequest = new VideoRequestDto
         {
@@ -1185,7 +1202,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             MaxHeight = maxHeight,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -1202,7 +1219,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             VideoStreamIndex = videoStreamIndex,
             Context = context ?? EncodingContext.Streaming,
             StreamOptions = streamOptions,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         return await GetDynamicSegment(streamingRequest, segmentId)
@@ -1267,6 +1285,7 @@ public class DynamicHlsController : BaseJellyfinApiController
     /// <param name="context">Optional. The <see cref="EncodingContext"/>.</param>
     /// <param name="streamOptions">Optional. The streaming options.</param>
     /// <param name="enableAudioVbrEncoding">Optional. Whether to enable Audio Encoding.</param>
+    /// <param name="alwaysBurnInSubtitleWhenTranscoding">Whether to always burn in subtitles when transcoding.</param>
     /// <response code="200">Video stream returned.</response>
     /// <returns>A <see cref="FileResult"/> containing the audio file.</returns>
     [HttpGet("Audio/{itemId}/hls1/{playlistId}/{segmentId}.{container}")]
@@ -1328,7 +1347,8 @@ public class DynamicHlsController : BaseJellyfinApiController
         [FromQuery] int? videoStreamIndex,
         [FromQuery] EncodingContext? context,
         [FromQuery] Dictionary<string, string> streamOptions,
-        [FromQuery] bool enableAudioVbrEncoding = true)
+        [FromQuery] bool enableAudioVbrEncoding = true,
+        [FromQuery] bool alwaysBurnInSubtitleWhenTranscoding = false)
     {
         var streamingRequest = new StreamingRequestDto
         {
@@ -1365,7 +1385,7 @@ public class DynamicHlsController : BaseJellyfinApiController
             Height = height,
             VideoBitRate = videoBitRate,
             SubtitleStreamIndex = subtitleStreamIndex,
-            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.Encode,
+            SubtitleMethod = subtitleMethod ?? SubtitleDeliveryMethod.External,
             MaxRefFrames = maxRefFrames,
             MaxVideoBitDepth = maxVideoBitDepth,
             RequireAvc = requireAvc ?? false,
@@ -1382,7 +1402,8 @@ public class DynamicHlsController : BaseJellyfinApiController
             VideoStreamIndex = videoStreamIndex,
             Context = context ?? EncodingContext.Streaming,
             StreamOptions = streamOptions,
-            EnableAudioVbrEncoding = enableAudioVbrEncoding
+            EnableAudioVbrEncoding = enableAudioVbrEncoding,
+            AlwaysBurnInSubtitleWhenTranscoding = alwaysBurnInSubtitleWhenTranscoding
         };
 
         return await GetDynamicSegment(streamingRequest, segmentId)