1 files changed, 19 insertions, 1 deletions
diff --git a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
index 274e82d823..9952c10c3a 100644
--- a/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
+++ b/MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs
@@ -6315,7 +6315,7 @@ namespace MediaBrowser.Controller.MediaEncoding
                         string.Join(',', overlayFilters));
 
                 var mapPrefix = Convert.ToInt32(state.SubtitleStream.IsExternal);
-                var subtitleStreamIndex = FindIndex(state.MediaSource.MediaStreams, state.SubtitleStream);
+                var subtitleStreamIndex = GetSubtitleStreamIndexForFfmpeg(state.MediaSource, state.SubtitleStream);
                 var videoStreamIndex = FindIndex(state.MediaSource.MediaStreams, state.VideoStream);
 
                 if (hasSubs)
@@ -7947,6 +7947,24 @@ namespace MediaBrowser.Controller.MediaEncoding
             return -1;
         }
 
+        public static int GetSubtitleStreamIndexForFfmpeg(MediaSourceInfo mediaSource, MediaStream subtitleStream)
+        {
+            var index = FindIndex(mediaSource.MediaStreams, subtitleStream);
+            if (index == -1 || subtitleStream.IsExternal || mediaSource.VideoType != VideoType.BluRay)
+            {
+                return index;
+            }
+
+            var hiddenStreamsBefore = mediaSource.MediaStreams.Count(s =>
+                s.Type == MediaStreamType.Audio
+                && !s.IsExternal
+                && (string.Equals(s.Codec, "truehd", StringComparison.OrdinalIgnoreCase)
+                    || string.Equals(s.Codec, "atmos", StringComparison.OrdinalIgnoreCase))
+                && s.Index < subtitleStream.Index);
+
+            return index + hiddenStreamsBefore;
+        }
+
         public static bool IsCopyCodec(string codec)
         {
             return string.Equals(codec, "copy", StringComparison.OrdinalIgnoreCase);