For burn in of 10 bit data, yes. 10 bit data is usually only present in HDR
@Schmitzke what os are you running your server on?
Much better! x264 was no problem at all for my iGPU. With x265, a single 4K HDR → FHD HDR with burn-in maxes out the UHD 770 by 30-50%.
Windows 11.
I’ve just bought an RTX A2000 and am looking at the performance. Two simultaneous transcodes (4K HDR with burn-in) would be desirable.
@chris_decker08 Is there anything weird about that file or anything showing up in my logs of why playback would be hanging up when getting transcoded to h265 rather than h264 at the same bitrate?
Tautulli is showing a comparable transcode speed and buffer for both when playing
@Schmitzke i am working on something that may make you happy assuming you are using image based subtitles (such as PGS). unfortunately there isn’t a ton that can be done server side for improving the performance of burning in text based subtitles, however the client engineers are working on something that will take a bit longer to roll out 
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@Kgtree is it refusing to play completely or just buffering a lot?
The file will start playing but, it just hangs up on the screen for a second or two and resumes playing. It doesn’t show as buffering with Tautulli.
It exhibits the behavior on Tvos, Tizen, and Roku.
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sounds like its just taking a little longer to buffer for hevc than h264. I’m not sure how Tautulli would detect client side buffering so i’m not sure how much i would trust it.
Hey, I don’t use PGS at all. I’m always busy creating SRT subtitles.
I figured that there’s hardly any room to improve the performance when it comes to burning in subtitles.
I think the goal has to be to avoid burning them in altogether. As far as I know, Emby, for example, can handle direct subtitle streaming on WebOS, even when audio/video is being transcoded.
For me personally, the issue is probably resolved for now with the new RTX A2000.
Thank you for your tireless dedication!
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The performance of burning in srt subtitles for hevc should be be equivalent to burning them in for h.264, especially since it is all cpu based it shouldn’t be touching your igpu at all…
Is the burning completely CPU-based? But why does the encoding speed increase from 0.7 to over 1.0 without burning then?
I’m confused. 
Burning in text based subtitles is cpu based and thus slower than if everything was done on hardware. It can only go as fast as its slowest part, and in this case thats likely the burn in. It does as much processing as it can on the gpu, downloads the data to the cpu, preforms the burn in then re-uploads to the gpu for encoding. Since only the encoder should be different in that pipeline, hevc vs h264 should be affected by the burn in the same way
Will this feature apply to downloaded content as well?
Need to replace my iPad which is loaded with content for travel, and trying to determine how much storage capacity to look for as Black Friday approaches. If HEVC transcoding applies in the short term, I’ll probably stick with my current storage capacity and assume I’ll get more mileage out of it. If not, I’ll probably upgrade the storage capacity.
this works for for files transcoded on the fly and optimized versions, at the moment tho there isnt any benefit you get the same quality at the same bitrate and same file size but right now they are just trying to get it to work properly, later we will see the benefits
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Had the buffering issues for about a week also after the most recent update. I kept thinking something was wrong with my internet. I went crazy and bought a new wifi mesh and an expensive USB WiFi stick for my PC-Plex server. After that, the buffering was less frequent but still paused every min or so for about 2 to 3 seconds then it would continue playing. I lowered the quality of everything, limited my upload limit, changed multiple settings and I was still running into the same problem. Movies and Shows with PGS subtitles would transcode then freeze eventually. I got srt files for them and the issue persisted, was always transcoding and all videos lagged even at a 2MB video quality setting. While I was constantly testing my many changes on the Plex server I would get random notifications that my wifi security camera would go down, which kept me thinking that it was still my wifi was the problem. After 8 hours (today) of trying multiple changes and online searching, I realized it was Plex causing my internet issues as it was constantly trying to transcode the video with PGS file pulling lots of bandwidth and bottle necking network resources causing my cameras to disconnect. Crazy! Even when I disabled the subtitle file from displaying, the video would still paused and buffered. I changed all the burn subtitles options also and the same issues stayed.
This lead me to uninstall the current version and install the previous version I had.
The issues are gone.
Windows 10 PC: AMD Ryzen 7 3700x 8-Core Processor
Video Card: Radeon RX 580 Series 8GB
Please open a new thread.
This thread is specific to testing hardware accelerated transcoding to HEVC video, which is not supported on AMD GPUs.
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I have verified the same behavior I described in my previous post on an Xbox Series X running the current build of the Xbox OS.
Based on the response to that post, I have no interest in providing any further information. Good luck figuring it out.
For what its worth, I have an Intel Arc 310 in Ubuntu and Xbox Series X that is up to date and I do not have this issue. Have you updated the firmware in your card?
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I have updated the links with a build which improves subtitle burn in performance of image based subtitles (such as PGS) with Intel devices on windows and Nvidia devices everywhere. This should bring the behavior of burning in subtitles with HEVC up to par with the behavior of h.264.
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