Go into your Plex Server Settings->Transcoder and make sure the following are enabled:
-Enable HDR tone mapping
-Use hardware acceleration when available
-Use hardware-accelerated video encoding
What Video Card do you have? Are you sure it supports HEVC decoding?
Does your video have subtitles? HW Transcoding doesn’t support burning in subtitles.
Already have these settings enabled. I have an Nvidia RTX 2060, it does support HEVC decoding for sure.
Though my video does have subtitles, HW transcoding works fine without tone mapping and with subtitles, so I am a bit confused…
HW Transcoding works with direct playing or transcoding subtitles but it doesn’t support burning-in subtitles.
Try turning off subtitles to see if it makes a difference.
You should also double check to make sure you have 64-bit PMS:
I installed just yesterday the 64-bit version to be extra sure. I will try tonight turning off subtitles to see if it changes anything.
Does your video have Dolby Vision? Plex doesn’t support hardware transcoding for Dolby Vision.
The only other thing I can think of is to make sure you have the latest Nvidia drivers. If it still doesn’t work, I’m out of ideas. Hopefully, someone else in this forum can help you.
Oh it might be dolby vision, I need to double check (is it stated directly in Plex?) and I have the latest drivers
Edit : it is Dolby Vision
You’re gonna have to stick to HDR10 video if you want HW Tone Mapping.
Plex won’t support Dolby Vision anytime soon since it requires a licensing fee.
I see. Thanks for your advice!
I have other news: I tried with several different files, and each times it doesn’t work. Even when not using Dolby Vision…
EDIT: Some files work but I’m unsure why. Maybe WEB-DL works but not a bluray-remux (both not Dolby Vision). Is IMAX supported?
IMAX just means it was filmed with a high resolution with a certain aspect ratio and is unrelated to HDR, so it would have no effect on HW Tone Mapping.
I have no issues with Web-dl files or Bluray remux with HW Tone Mapping.
What client do you use? Have you tried different devices?
I have tried with different devices and it responds differently, most of the time because of the audio that may or may not need to be transcoded, and to be sure I make my tests on the web browser directly, because the windows client is mostly using direct play.
Each of my files are HDR10 and HEVC main 10 encoded, so I don’t really understand why some of them are so different.
EDIT: The issue might be coming from audio transcoding, how is DTS-HD compared to EAC3?
If a video Direct plays, you can manually lower the quality and it will start transcoding. So you may want to try the Windows Client again.
Audio is always transcoded using CPU so it has no effect on HW transcoding.
I forgot to ask what CPU do you have. Does it have Intel Quicksync? Just wanted to confirm that Plex is using your Nvidia GPU for HW transcoding and not your CPU.
I have an AMD Ryzen 3 3100 4-Core, so not the best out there unfortunately…
I’m glad I found the problem, I need to fix it now (it does come from the resolution, but it transcode both audio and video, which is not ideal)
Now for some reasons the windows client does not really “transcode” the audio, though my OSMC does, which is annoying
I don’t see how resolution can affect HW Tone Mapping.
The Windows Client doesn’t transcode the audio because it supports it. Transcoding only occurs when the format isn’t supported by the client.
The problem isn’t from Tone Mapping, or at least it is my conclusion.
EAC3 5.1 should be supported by my Raspeberry, since other files in h264 with the same audio codec are working fine (no transcoding necessary). Though it is transcoded for some reasons instead of being passed through, and I can’t figure out why. I have the exact same issue with DTS-HD-MA 5.1
Have a weird one as well.
If tone mapping is off, forced transcoded video plays using 6% cpu 42%gpu
If tone mapping is off and PSG subs activated, forced transcoded video plays using 22% cpu 42% gpu
If tone mapping is on forced transcoded video plays using 89% cpu 0% gpu
If tone mapping is on and PSG subs activated forced transcoded video plays using 40% cpu 35% gpu
Why cant I utilize Hardware Acceleration with Tone Mapping unless I turn on the subtitles?
Player is just the plex web open on a windows client.
Video is
Codec HEVC
Bitrate 99358 kbps
Bit Depth 10
Chroma Location topleft
Chroma Subsampling 4:2:0
Coded Height 2160
Coded Width 3840
Color Primaries bt2020
Color Range tv
Color Space bt2020nc
Color Trc smpte2084
Frame Rate 23.976 fps
Height 2160
Level 5.1
Profile main 10
Ref Frames 1
Width 3840
Display Title 4K HDR10 (HEVC Main 10)
Extended Display Title 4K HDR10 (HEVC Main 10)
PMS: 64bit 1.30.0.6406
Thanks!
Just wanted to comment, +1 for Plex HDR to SDR Tone Mapping in Windows using Intel GPU.
