Server Version#: 1.24.5.5173 My Server: OS: Unraid CPU: Intel i7-5930K GPU: GTX 1080Ti RAM: 16GB My client: Samsung QN90A TV. My problem: Most 4K Blu-ray rips use PGS subtitles, which I have discovered is an image-based format that my TV doesn’t support natively, so Plex is forced to transc…

Yes, Burning subtitles (VOBSUB, DVDRIP, or PGS) impede HW transcoding. What you see is: HW decode CPU subtitle burning on each video frame HW encode of the resultant video frame. When subtitle burning is active, the transcoder ‘(HW)’ output is suppressed so you know it’s not doing everything …

Thanks for the info @ChuckPa , good to know why it isn’t working. Is there some way I could upgrade my server to make this work, or is 4k video with burned subtitles currently an impossibility on Plex?

@talsemgeest If, as part of your media curation process, you take the time to burn in the one subtitle which you will use, leaving only audio and video streams in the file, hardware transcoding will then work normally. This is because the subtitle text will have become an integral part of the…

[image] ChuckPa: Now, if you have a strong enough machine, (i7-7700 or above), you won’t notice the burning until you get more than 3 streams burning 4K subtitles and transcoding audio Well, I do have a i7-8700 an whenever I try to transcode a 4K movie (HDR) with hw transcoding turned on and …

Thanks alot for the reply, but I’m already doing this to circumvent this problem. I’m just curious why this is happening and if there is a solution to this problem. If it should be possible to watch three streams in parallel with burning, I wonder why I am not able to watch a single one. I also tri…

[image] Pugnator: I also tried it with hw transcoding turned off, but the problem still remains. (However, it seems that it buffers slightly less often). It is also happening on my second plex server (i7-7700 root server at Hetzner). I disabled tonemaping and not hw transcoding. By that I wan…

[image] Pugnator: Well, I do have a i7-8700 an whenever I try to transcode a 4K movie (HDR) with hw transcoding turned on and a subtitle that is not supported by the player (for example pgs in Plex Web or VobSUB in Android), the movie buffers every 10 to 15 seconds. The CPU is at 20% average. I…

Thank you very much for this detailed response. So I assume that I have the following options: Continue to convert (at least forced) subtitles to srt as a workaroud. Switch to a CPU with an even higher single core performance than a i7-8700 (but I don’t know what performance is sufficient). …

Transcoding 4K movies with PGS subtitles

Plex Media Server

OttoKerner December 7, 2021, 1:57pm 6

Alternatively, acquire a SRT version of the subtitles (at the interwebs) or convert the PGS stream to SRT. Introduction: convert image-based subtitles to SRT with Subtitle Edit

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Transcoding 4K movies with PGS subtitles

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