I’m Having some strange behaviors with my PMS and HEVC. This could all be for nothing as I’m looking for a 10 series Nvidia Card for HW transcoding h.265, but whats happening is strange.
To start I run a dual Xeon x5680. Each is 6 cores, 12 threads @3.33Ghz and a GTX970.
I’m having issues transcoding certain movies, but for the life of me cant figure it out. In all scenarios I’m going to 12mbps 1080p
If I try to transcode The Lego Movie 2 The Second Part (59690 kbps 10bit HDR 4k, 7.1) it buffers every 30 seconds or so and will only use a max of 33% CPU
On the other hand if I try to transcode Despicable Me 3 (66556 kbps 10bit HDR 4k, 7.1) it never buffers, and my cpu usage sits at 50-70%.
How is it that the higher bitrate movie has no issues?
*edit - I’ve discovered that the main difference is that the files having issues are flagged as HDR10
Server Version#: 1.16.6.1592
Player Version#: 7.21.0.12255
sorry if this seems insensitive, but why bother. HDR transcoding will yeild garbage quaility result even if you get this working. till tone mapping is fixed, I suggest you spend your time on getting direct stream working, or ignore 4K if you can’t.
Your response is from ignorance which I can understand. My main setup is an nvidia shield which direct plays these files to my 4K projector and atmos setup. However when I’m out I like to stream to my phone and due to limited UL bandwidth I have to transcode, as well I have a friend that uses it sometimes on a roku which again requires transcoding. Yes the video looks washed out but it’s really not that bad on phone displays.
Hey that’s a nice rig. From a quick search, that Xeon x5680 does not support QSV,
as it came out in Q1 2010, and QSV came out in Q1 2011.
Real time software transcoding is difficult.
If you’re curious enough to dig into the details, you can upload the XML data from those two files.
On a good note, head on over to the New Transcoder Preview thread, where you can run a PMS that will do many simultaneous 4K HDR transcodes on your Nvidia GPU.
Thanks. Truthfully I got a killer deal on the hardware on Ebay. I knew it wouldn’t have QSV but was hoping the CPUs power would be enough, and for the most part it held on the older uhd titles. I’ll definitely check out the threads you linked!
Yeah that’s why I’m looking at a 10 series card, 1050 or higher. Although used cost it makes more sense to jump to a 1650. I’m just unsure of the Volta NVENC being in it. It shows support for everything except B frame but I’m not sure if plex even uses that or maybe would in the future.
GPU Ram seems to be a limiting factor, so, given a choice, pick the model with more VRAM.
That being said, I still wouldn’t be spending any money till the current issues are hammered out, not unless you are willing to “get it wrong” and then change in the future.
IMO if you’re going to do it I’d get the 1660 or better since it’s full support for hevc. I used the 4K 10 bit 400 MBs jellyfish test video and it transcodes on mine ok, not much cpu usage - I’m running a single x5670 & a rx 560 in an old Mac Pro. It used to be on a dual x5670 Linux box but had other issues I couldn’t solve.
I ran the 140Mbps HEVC HDR file and it transcoded just fine on my CPUs alone, the 400Mbps file struggled and exhibited the same behaviors that the UHD movies had. This makes even less sense now. Because in theory then the 50Mbps movie shouldnt have an issue…
Maybe it’s different audio and different burst transfer rates? Jellyfish is pretty static.
After a good number of hours trying to debug my QNAP, I’ve come to the conclusion that Analyze is our friend. Select your Lego movie and analyze it. Then try to play it again. Still as choppy?
Try a version of Lego movie without any audio track that you’ve analyzed. Still choppy?
What are the audio streams, truehd/atmos, or dts-hd-ma?
are they same for both movies?
do you have subtitles enabled for either movie? both? or none?
post the screenshots of the server status now playing for both movies, like how the jellyfish example is posted above.
you can also watch the bandwidth used by both to see the real time network use. The bitrates shown above are simply static averages, 4k/hdr remuxes can easily burst exceeding 100mbits (more than fast ethernet can handle).
Its definitely not network related as I’ve streamed higher bitrate movies. The temp folder is linked to a dedicated ssd in the server, this I just recently did due to the transcoding issues, no improvement.
I’ve attempted selecting even the stereo audio track inside the Lego movie 2, with no change. Bandwidth is well within limits as I’m running 1gig lan. The main problem I’m noticing is with CPU utilization. It’s not using enough. I’ll post screenshots when I get off work.
if you have selected the stereo audio track and it still buffers, then I would expect it is something specific to the encoding of that particular video.
It is only that video, or do other ATMOS or even DTSMAHD movies also buffer?
GTX970 according to the nvidia chart, does not support any x265 decoding.
So I would suspect, the only HA you get is ENCODING to x264 12mbps 1080.
The server status now playing screenshots will show the truth.
I have a 1650 and can recommend that, otherwise buy whatever 10 series or newer card with the most video ram you can afford.
I don’t see if you posted your OS, but on linux, video ram is the bottleneck for 4k transcoding.
Also if you are on linux, unless you were using the plex transcoder ‘hack’ or the new transcoder preview release, there is NO nvidia decoder support at all, meaning CPU has always been decoding 4k.
If you are using windows, that might be entirely different. Windows uses DXVA, not NVDEC.
