On further hammering, the Windows transcoder is having issues with HEVC and AVC decoding for me. Intel Graphics 600. MPEG2 works great, funny enough.
For me, HW transcoding no longer engages at all with Intel Graphics 630 on W10.
It seemed to work initially last night when I instaled the beta and had a quick look.
However today It just doesn’t work.
Rolling back to the latest stable release and non-beta hardware acceleration is fine.
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That is what I have observed as well. HW transcoding fails with all video codecs on a NUC8i7BEH/Windows 10 v1809/PMS v1.16.7.1573
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has anyone defined “zero-copy hardware transcoding”
for qualifying transcodes (hardware)
does this mean
bypass transcode to temp?
transcode on demand straight upload to (client buffer) or remain in ram ?
Yeah I guess it just seemed odd how it definitely worked last night when I installed initially.
I tested it with my 4K HDR remuxes and the odd 1080p VC-1 file and was pretty impressed.
But today I couldn’t get HW acceleration on anything at all until I rolled back.
Personally I’m not on an NUC just a regular PC with an i7-7700k KabyLake.
It means that the transcoding does not leave the video memory buffer across the PCIe bus to system memory. This allows for much better performance since there is no copy of the raw decoded frames to and from main system memory.
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Doesn’t really matter since it is just QSV at the end of the day.
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Got it thank you.
I’m now seeing this behavior too: Stuff that worked last night is no longer working today.
A separate quirk: I tried playing a 720p MPEG2 file via browser. The browser can never direct-play MPEG2 of course so transcoding should be automatic. But instead, the dashboard showed direct play for until it reached 00:18 (18 seconds), where it seemed to think it was successfully playing in the browser (it was not). After 18 seconds it clicked over to (non-hardware) transcoding and it was fine after that.
I noticed similar last night: It tried to direct-play something that was clearly unsupported, then eventually realized and switched to transcoding. It leads to 10+ seconds of delays before actual playback on PlexWeb.
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When reporting a new issue in this build, please include your Plex Media Server logs and a sample file that reproduces the issue. You can also post specific log snippets to point us at a specific area you think is suspicious, but we need the full log file to properly diagnose problems.
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I’m not sure where that ~1.4GB number comes from, but it’s higher than I’d expect. We can come up with a theoretical lower bound on memory usage for a 4K->1080 transcode like this:
Input: 3840 * 2160 * 2 * 1.5 * 6 = 149299200 bytes ≈ 150MB
(that’s 3840x2160 pixels, 2 bytes per 10-bit channel, 1.5 samples per pixel [4:2:0], and 6 buffered frames [the maximum for 4K at level 5.1, the UHD BD max])
Output: 1920 * 1080 * 1.5 * 4 = 12441600 bytes ≈ 12MB
(1920x1080 pixels, 1.5 samples per pixel, 4 buffered frames [maximum for 1080p at level 4.1, a common client value])
Some clients may support higher levels, in which case depending on your settings we could end up with a decoded picture buffer of up to 16 frames, so swap the 4 out for a 16 to get ~50MB. This means about 200MB per transcode as our theoretical minimum.
In practice the value will be higher, because there’s a fair bit of (video) memory usage in the transcoder outside of the decoder and encoder’s DPBs themselves; the largest other use would be uncompressed frames buffered at other layers (such as the filter graph, particularly around the scaler), allocated-but-currently-unused frame buffers, and buffers holding compressed video data. This means that 350MB of usage per transcode involves a fairly reasonable ~75% overhead over our theoretical minimum.
The ~1.4GB figure is interesting, and I’m not entirely sure how to explain it. It could simply be that the way CPU copy-back is implemented in ffmpeg involves very heavy memory overhead, or it could be a measurement error.
Also, keep in mind that zero-copy will substantially reduce memory bandwidth requirements as well. A lot of the data on that page isn’t going to be accurate anymore.
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There was some work within PMS to detect support and configure the transcoder for it, and a fair bit within ffmpeg to support GPU-side scaling, and particularly 10-bit → 8-bit downconversion with dithering (along with 4:4:4:/4:2:2 → 4:2:0).
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I have consistently gotten ~1.4g video ram usage since the release of the “patch” and now this preview release.
The screen shots in the second post are what I get for the transcode sessions being shown.
I would be happy for anyone to provide firm confirmation of same, or proof of your suggested estimate.
I am on Proxmox 6 Debian 10 with nv drivers indicated in the nvsmi shot.
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What is the recommended driver version for Nvidia GPU’s with this release?
FIXED
The minimum required Nvidia driver for nvenc is 418.30 or newer
Oh man you guys are going to make so many people happy.
I have installed this version, however hardware transcoding just isn’t working. When I revert to an earlier dot release, and hack in nvdec support via a bash script pointing to “Plex Transcoder2” it works again.
Plex Media Server.log just continually spams:
Aug 26, 2019 09:17:03.210 [0x7fb2f53da700] ERROR - [Transcoder] [matroska,webm @ 0xe7d380] Invalid track number 7
Aug 26, 2019 09:17:03.221 [0x7fb2f63dc700] ERROR - [Transcoder] [matroska,webm @ 0xe7d380] Invalid track number 7
Aug 26, 2019 09:17:03.256 [0x7fb28affd700] ERROR - [Transcoder] [matroska,webm @ 0xe7d380] Invalid track number 7
Aug 26, 2019 09:17:03.278 [0x7fb2d3fff700] ERROR - [Transcoder] [matroska,webm @ 0xe7d380] Invalid track number 7
Aug 26, 2019 09:17:03.303 [0x7fb2e17fa700] ERROR - [Transcoder] [matroska,webm @ 0xe7d380] Invalid track number 7
Aug 26, 2019 09:18:18.370 [0x7fb2f4bd9700] ERROR - [Transcoder] Error while decoding stream #0:2: Invalid data found when processing input
Aug 26, 2019 09:18:18.375 [0x7fb2e17fa700] ERROR - [Transcoder] [matroska,webm @ 0xe7d380] Invalid track number 7
Aug 26, 2019 09:18:18.396 [0x7fb2f53da700] ERROR - [Transcoder] [hevc @ 0x10f0bc0] Could not find ref with POC 5
Aug 26, 2019 09:18:18.397 [0x7fb255ffb700] ERROR - [Transcoder] [hevc @ 0x10f0bc0] Could not find ref with POC 10
Aug 26, 2019 09:18:18.434 [0x7fb2e17fa700] ERROR - [Transcoder] [subrip @ 0x10d35c0] Invalid UTF-8 in decoded subtitles text; maybe missing -sub_charenc option
Aug 26, 2019 09:18:18.435 [0x7fb2d3fff700] ERROR - [Transcoder] Error while decoding stream #0:2: Invalid data found when processing input
Aug 26, 2019 09:18:18.435 [0x7fb2f4bd9700] ERROR - [Transcoder] [subrip @ 0x10d35c0] Invalid UTF-8 in decoded subtitles text; maybe missing -sub_charenc option
Aug 26, 2019 09:18:18.436 [0x7fb2f53da700] ERROR - [Transcoder] Error while decoding stream #0:2: Invalid data found when processing input
Aug 26, 2019 09:18:18.437 [0x7fb255ffb700] ERROR - [Transcoder] [subrip @ 0x10d35c0] Invalid UTF-8 in decoded subtitles text; maybe missing -sub_charenc option
Aug 26, 2019 09:18:18.438 [0x7fb28affd700] ERROR - [Transcoder] Error while decoding stream #0:2: Invalid data found when processing input
Aug 26, 2019 09:18:18.439 [0x7fb2f63dc700] ERROR - [Transcoder] [subrip @ 0x10d35c0] Invalid UTF-8 in decoded subtitles text; maybe missing -sub_charenc option
What version of the nvidia driver are you on?
430.34
h264/1080p transcoding works fine. Its only h265/hevc/4k that it just sits there and spins in a circle on my screen.
those look like bad rips/invalid subtitles?, did you try multiple 4k movies ?
otherwise they will probably want the logs and sample file as requested in OP.
If anyone needs a working PKGBUILD, I’ve built one with the latest links (as of a few minutes ago - we are now on 1.16.71574 ). If you are in need, ping me and I’ll send you a link.
I can confirm that the hw transcoding is working on my rig, but I can’t view anything under the “settings” and “manage” tabs on the web interface. I just get an exclamation point sign and a message which says, “server settings are unavailable.”
Is anyone else experiencing this? (I’m guessing it’s a permissions issue. ?)
When reporting a new issue in this build, please include your Plex Media Server logs and a sample file that reproduces the issue. You can also post specific log snippets to point us at a specific area you think is suspicious, but we need the full log file to properly diagnose problems.
