This is happening a lot, so I thought maybe I could bump this and they can try and get to the bottom of it.
tl;dr: If for any reason the audio needs to be transcoded then the subs are burned in, causing the video to be transcoded as well, even for files where direct play of the subs works when the audio is not transcoded.
As an example, see this image:
On the left is AC3 5.1 and on the right is AC3 2.0. All I did was start the file and then change the audio track from 5.1 to 2.0 and, as you can clearly see, everything Direct Plays just fine with AC3 2.0, including the forced subtitles, but requires complete transcoding with AC3 5.1, because it has to burn the subs.
That’s a huge amount of resources being used up just because the audio needs to be transcoded.
I’m also attaching the client logs where you can see the MediaDecisionEngine clearly say in regards to the AC3 5.1 stream:
Unable to direct play; AC-3 audio is not supported by the device
Even though 14 seconds later it decides AC-3 2.0 is just fine.
Regardless, I don’t care if it’s transcoding the audio stream, what I do care about is that consequently if the audio needs transcoding then it’s also transcoding the video stream in order to burn in the subtitles, which is completely unnecessary as they direct play just fine when the audio doesn’t need transcoding.
I hope I’ve explained this clearly enough. If the devs have any questions, or want me to do more tests or provide more info, don’t hesitate to ask. I’m happy to provide a video sample if a dev responds and asks for it.
Client: Nvidia Shield
Plex Version: 22.214.171.12428
PMS: Windows 10 126.96.36.19985
Setup: Shield direct via HDMI to Stereo Samsung TV, no audio receiver/etc.
File Information: See Attached MediaInfo