I am not aware of the requirements for 4K transcoding, but in the near future I may be able to lay my hands on a i7-4790 game pc. I read the passmark score, which is almost 10k. Will this be enough for 1 4K transcode, and at which bitrate?
Can anyone tell me?
Here’s the link to the processor:
Intel: https://ark.intel.com/products/80806/Intel-Core-i7-4790-Processor-8M-Cache-up-to-4_00-GHz
Benchmark: https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-4790+%40+3.60GHz
Gr, Johan
Hi everyone, would like a little advice please. I’m looking to build a HTPC. I was just wondering how well a Ryzen 5 2400G (built in Vega GPU) would handle high bitrate 4K HEVC video? I’m assuming direct play won’t be an issue but transcoding to other devices will??
I suggest the cheaper alternative…
NEVER transcode 4K…
Create 1080p versions for all your non-4K capable users…
Works great for me and nobody is denied access to my server just because I am transcoding a 4K video.
I’ve tried 1080p versions, but letting Plex create those automatically wasn’t reliable, and I’m generating too many 4K videos to have time to convert them all manually. Think daily clips of the kids.
Also, I built a Core i5 tower and I’m still suffering buffering when transcoding. Direct streaming is fine. Sounds like some people are having luck with the Core i7 (6900), and that may be the way to go for 4k transcoding. Here’s my build.
Core i5 7600k
16 GB DDR4 ram G.Skill Ripjaws V series
Gigabyte G1 Gaming GA-Z170X-Gaming 7 motherboard
no GPU, cause, well, Plex doesn’t utilize GPU’s. Though I’m still curious about hardware acceleration with Nvidia cards.
Computer is hardwired to the router
Which is hardwired to my Nvidia Shield TV
Which is plugged into a receiver that doesn’t support 4K, but has amazing audio
Since the Stereo doesn’t support 4K, it has to get transcoded to 1080p and begins to buffer.
My 4k Vizio TV has Googlecast built in. I can cast from my phone to the TV just fine, since that direct plays.
Well I use an i7 with passmark of 8k with 4 gig ram, 256gig ssd, and it can barely transcode 1 4K video without buffering.
It also has QuickSync for hardware transcoding assist.
Soooo… extrapolate that to your situation for what it’s worth.
Thanks for that input jjrjr1. I’d love to know which Core i7 processor you’re using.
4K Plex transcoding will be smooth only with a minimum 6 core intel 8th gen or newer cpu, PERIOD! end of discussion
I have an i9 7900x and I seem to be having issues transcoding 4k.
Any thoughts?
Also when I watch the stats in tautulli I see that if I select original quality and pgs subtitles it will downscale my 4k to 1080 and usually strips the hdr.
@Johnsontom7827 said:
I have an i9 7900x and I seem to be having issues transcoding 4k.
Any thoughts?Also when I watch the stats in tautulli I see that if I select original quality and pgs subtitles it will downscale my 4k to 1080 and usually strips the hdr.
What client are you watching on. Most do not support PGS subtitles, which means PMS has to burn them in. This means a full video transcode. When PMS transcodes, it can only produce 1080.
@“MovieFan.Plex” said:
@Johnsontom7827 said:
I have an i9 7900x and I seem to be having issues transcoding 4k.
Any thoughts?Also when I watch the stats in tautulli I see that if I select original quality and pgs subtitles it will downscale my 4k to 1080 and usually strips the hdr.
What client are you watching on. Most do not support PGS subtitles, which means PMS has to burn them in. This means a full video transcode. When PMS transcodes, it can only produce 1080.
LG WEB OS Mainly.
When I look at my resources though when transcoding my cpu barely breaks a sweat usually sits at about 20 - 30% utilization.
How can remove the buffering issues at least during transcoding?
@abs_rio said:
Hi everyone, would like a little advice please. I’m looking to build a HTPC. I was just wondering how well a Ryzen 5 2400G (built in Vega GPU) would handle high bitrate 4K HEVC video? I’m assuming direct play won’t be an issue but transcoding to other devices will??
Has anyone ever compared Vega to UHD630 for picture quality? My UHD630 isn’t fast enough for some 4K HEVC media so i’m considering upgrading to a 2400G.
@“Plex Server 012” said:
4K Plex transcoding will be smooth only with a minimum 6 core intel 8th gen or newer cpu, PERIOD! end of discussion
AMD’s Threadripper lineup would beg to differ, but I see your point. Newer Intel CPUs have the graphics block changes to support H.265 8/10bit encode/decode in hardware. A high enough passmark can overcome lack of hardware support though, it’s just not the most practical when you start talking about multiple 4k HEVC transcodes.
@Johnsontom7827 said:
I have an i9 7900x and I seem to be having issues transcoding 4k.
Any thoughts?Also when I watch the stats in tautulli I see that if I select original quality and pgs subtitles it will downscale my 4k to 1080 and usually strips the hdr.
The Plex Media Server component does not currently support HDR via transcode, it can only pass through HDR metadata to clients that support HDR directly (Shield is popular, but I use Plex for Kodi w/ DSPlayer and it works fine). This isn’t really Plex’s fault IMO as tone mapping is still a very actively developed and requires a lot of underlying metadata info (maxCLL, maxFALL, Lmax, Lmin, not to mention color data) to properly map the values. When that data is missing, the transcoder has to guess and there are a lot of different opinions as to what constitutes the best way to guess.
As for your i9, it should definitely be able to handle transcoding as it has a passmark around 22k. I have an AMD 1920x with a (roughly) 18k passmark and it works fine with 4k HEVC transcodes. Even while running an x265 encode in the background, it can do an HEVC 1080p→1080p transcode along with a 1080p HEVC direct play, and I’d expect more with the i9 due to the beefier passmark. Maybe it’s a chipset issue? PMS might not be properly using the chip hardware.
@Johnsontom7827 said:
@“MovieFan.Plex” said:
What client are you watching on. Most do not support PGS subtitles, which means PMS has to burn them in. This means a full video transcode. When PMS transcodes, it can only produce 1080.LG WEB OS Mainly.
When I look at my resources though when transcoding my cpu barely breaks a sweat usually sits at about 20 - 30% utilization.
How can remove the buffering issues at least during transcoding?
Burning in PGS subtitles can only utilize 1 CPU core, so the 20-30% you see is probably maxing out that 1 core and can’t go any faster. I would suggest switching to SRT subtitles, which can be burned in much easier and most clients do support direct playing them so it might not even need to be transcoded.
@“MovieFan.Plex” said:
@Johnsontom7827 said:
@“MovieFan.Plex” said:
What client are you watching on. Most do not support PGS subtitles, which means PMS has to burn them in. This means a full video transcode. When PMS transcodes, it can only produce 1080.LG WEB OS Mainly.
When I look at my resources though when transcoding my cpu barely breaks a sweat usually sits at about 20 - 30% utilization.
How can remove the buffering issues at least during transcoding?Burning in PGS subtitles can only utilize 1 CPU core, so the 20-30% you see is probably maxing out that 1 core and can’t go any faster. I would suggest switching to SRT subtitles, which can be burned in much easier and most clients do support direct playing them so it might not even need to be transcoded.
Actually no I look at each core breakdown and plex usually utilizes 10 cores all equally only using about 40 - 50 %.
Is PGS only a certain piece of the transcode? If so that’s just the layer pertaining to text one core should be fine for handling that anyway.
@onekmilesbehind said:
@Johnsontom7827 said:
I have an i9 7900x and I seem to be having issues transcoding 4k.
Any thoughts?Also when I watch the stats in tautulli I see that if I select original quality and pgs subtitles it will downscale my 4k to 1080 and usually strips the hdr.
The Plex Media Server component does not currently support HDR via transcode, it can only pass through HDR metadata to clients that support HDR directly (Shield is popular, but I use Plex for Kodi w/ DSPlayer and it works fine). This isn’t really Plex’s fault IMO as tone mapping is still a very actively developed and requires a lot of underlying metadata info (maxCLL, maxFALL, Lmax, Lmin, not to mention color data) to properly map the values. When that data is missing, the transcoder has to guess and there are a lot of different opinions as to what constitutes the best way to guess.
As for your i9, it should definitely be able to handle transcoding as it has a passmark around 22k. I have an AMD 1920x with a (roughly) 18k passmark and it works fine with 4k HEVC transcodes. Even while running an x265 encode in the background, it can do an HEVC 1080p→1080p transcode along with a 1080p HEVC direct play, and I’d expect more with the i9 due to the beefier passmark. Maybe it’s a chipset issue? PMS might not be properly using the chip hardware.
Thank you for the information.
How would I troubleshoot the chipset issue?
I have the GIGABYTE X299 AORUS Gaming 7 just for additional info.
Based on what @“MovieFan.Plex” is saying, the sub format might be causing a bottleneck, as the burn-in process for pgs subs isn’t (can’t?) be threaded/parallelized.
To test this, you could convert the PGS subs from a known-problematic input/source file to SRT using something like Subtitle Edit. Text-based subs like SRT have greater direct/native client support and would result in more direct play scenarios/transcodes not containing sub burn-in.
If you replace the current file (w/ embedded PGS subs) with the same file (w/ PGS subs removed/replaced by the SRT equivalent), you could then re-test playback to see if/how the behavior changes. I’d force a media analysis for whatever video you test with after it has been replaced, just so the PMS has the current media info to work with.
Hi, I have been looking through this forum with interest. I have an old server with 2x xeon x5650 @2.67ghz passmark at 7437, combined just shy of 15k passmark. Most of the posts so far concern regular i5 or i7 cpu’s. Are the rules different for xeon cpu’s regarding the transcode power for 4k files? I have a large library of 1080p and 720p MKV and I am looking to start with 4k. But won’t bother if my hardware is’nt up for the task. Many thanks!
Hi All,
I am playing 4K HDR HEVC video content in an MKV container to my Xbox One X. The video / audio initially play using Direct Play, which is great. I have a 1Gbps network between my Plex server on my Windows 10 PC (32GB RAM Core i7), and my Xbox One X, so there should be no issues streaming 4K content.
However, I get buffering issues, and the Plex client / server switches the stream from Direct Play to Direct Stream via the Plex transcoder, and as a consequence, the HDR stream (which looked great) ends up being SDR, but due to a lack of tone mapping the picture ends up looking washed out.
I notice that when the video is direct playing, the Plex Media Server on my PC is using around 253Mbps of network bandwidth. That looks odd to me, considering that the video being played is 54814 Kbps.
When the video is being Direct Played, as it is initially, should the Plex Media Server on my PC not be using around 54Mbps of network bandwidth?
Why is it using 253Mbps!!? Even at 253Mbps it shouldn’t really cause buffering I assume as I have a 1Gbps connection, but it does buffer, and drop to Direct Stream
Glenn
It seems that many people talk about transcoding 4K with a powerful CPU. But if you are hardware transcoding using intel integrated graphics, how low can you go with a CPU. I have heard that a Intel® Celeron® J3455 quad-core can transcode 4K when it is using hardware transcoding. But I don’t know if that included transcoding H.265 or just 4K H.264. Does anyone know if that CPU using it’s integrated graphics can handle all 4K formats for transcoding or just some formats?
