Can PGSSUB + unsupported audio result in video transcoding?

[invisman 6]

I am on latest beta of Emby Android TV app running on Google certified Android 8.0 TV. I have connected my TV to Sony HT-RT3 soundbar (via HDMI ARC) that supports only AC3 and EAC3 (no DTS). So if I play a video with DTS audio, Emby app transcodes audio alone and use the same video stream. All good and fine.

 

But of late I am starting to notice an issue. Consider the following the scenarios.

 

4K HDR Video

Dolby Digital+ 5.1 Audio

SRT subtitle

Result = Direct Playback

 

4K HDR Video

Dolby Digital+ 5.1 Audio

PGSSUB subtitle

Result = Direct Playback

 

4K HDR Video

DTS 5.1 Audio

SRT subtitle

Result = Direct video + Transcoded audio

 

But if

 

4K HDR Video

DTS 5.1 Audio

PGSSUB subtitle

Result = Transcoded video + Transcoded audio

 

Is this the expected behaviour? I am not sure why PGSSUB needs to be burned (resulting in video transcoding) if audio is an unsupported format. I mean the app displays PGSSUB just fine if the audio is supported. So what difference does it make to subtitle whether the audio format is supported or not?

[ebr 15440]

Hi.  Yes, this is expected.  PGS is a graphical format.  Once we have to "break apart" the video in order to convert the audio, the only way to then display those subs will be to burn them in on the server.  If you obtain text-based subs for the item, this will not be required.

 

Does that answer your question?

[invisman 6]

Yes it does. Thank you for confirming.