Transcoding Help

[mike3821 67]

So I did a pass through of my xenon-1200 v3 video card and attached it to the VM of Ubuntu.

it sees the device via lspci and Emby sees it in the options for transcoding but it fails to software with errors in the log files.

[Luke 42077]

Hi there, we're happy to help:

 

[mike3821 67]

I pulled this from the log.

 

Edited May 18, 2021 by mike3821

[Luke 42077]

Hi, please attach the original log files rather than a screenshot of the log file. Thanks.

[mike3821 67]

ffmpeg-transcode-.txt

ffmpeg-transcode-.txt

[mike3821 67]

ffmpeg-transcode-.txt

[mike3821 67]

Reading more on my device, I’m not sure it’s even going to perform good if I can get it working.

Do you see anything ?

[Q-Droid 989]

I could be wrong but I think this is a hardware detection problem. As far as I know Haswell CPUs do not have hardware support for HEVC but this session is attempting to do just that.

 

[mike3821 67]

23 minutes ago, Q-Droid said:

I could be wrong but I think this is a hardware detection problem. As far as I know Haswell CPUs do not have hardware support for HEVC but this session is attempting to do just that.

 

Hmmm...

Here is my dilemma. I could potentially be in the market for a server refresh. I currently use a Lenovo TS140 and I’m looking to upgrade to a Lenovo ST50 with a Xeon E-2286g 6.

Would this be able to transcode 4K without the need for hardware transcoding? This however supports intel quick sync too, so I imagine it should work with esxi pass through and allow hardware transcoding.

Edited May 19, 2021 by mike3821

[Q-Droid 989]

Like I said I'm not 100% certain. The devs would have to check your logs to be sure as it could also be a config issue. Wouldn't want to pull the trigger before you know for sure but yes, the Xeon E-2286g is newer and more capable in both regards - HW accelerated and software transcoding.

Have you tried forcing a transcode on an h.264 source to see if it's just HEVC that fails?

 

[mike3821 67]

13 minutes ago, Q-Droid said:

Like I said I'm not 100% certain. The devs would have to check your logs to be sure as it could also be a config issue. Wouldn't want to pull the trigger before you know for sure but yes, the Xeon E-2286g is newer and more capable in both regards - HW accelerated and software transcoding.

Have you tried forcing a transcode on an h.264 source to see if it's just HEVC that fails?

 

No. Hardware transcoding is newer to me. Never bothered to ever figure it out.

I also realized trying to transcode 4K takes a very powerful processor or a good GPU which neither of them I have.

Plus I’m not spending cash on the over priced video cards out there.

[Q-Droid 989]

The 4k media is part of the equation, the encoding used for the video is another. HEVC (h.265) is more demanding than h.264 and the older the CPU/GPU the less likely it is to support HEVC encoding/decoding in hardware. Your current CPU may or may not support HEVC while a new one with iGPU like the Xeon you mentioned does.

If you pick a video encoded in h.264 from your library and change settings on the client to alter resolution or bitrate it should force transcoding on the server. Then you would know if your config is allowing GPU passthru. If it works and transcodes using the HW accel then the config should be fine and it's a problem with HEVC. If it doesn't work with h.264 then the GPU passthru needs some tweaking.

 

[mike3821 67]

Is this transcoding via hardware?

[Q-Droid 989]

Yes, that's using HW.

 

[mike3821 67]

Just now, Q-Droid said:

Yes, that's using HW.

 

Awesome! Thanks this makes sense. Lots to learn. Been researching this all night.

So if I move ahead with the newer system and processor I mentioned, I likely will be able to transcode h.265 with it, but not necessarily 4K?

[Q-Droid 989]

That CPU definitely supports h.265 up to 10-bit and definitely 4k even for multiple simultaneous streams.

From the log it looks like the session that failed was HEVC 10-bit. So what you could to as a test, to see if your CPU can handle it, is go in Transcoding -> Advanced and disable the HEVC Decoder so that it tries decode in software but encode in HW. The CPU might choke or at least get pegged for a while.

Still would like to know what the devs have to say about the errors you got.

[mike3821 67]

17 minutes ago, Q-Droid said:

That CPU definitely supports h.265 up to 10-bit and definitely 4k even for multiple simultaneous streams.

From the log it looks like the session that failed was HEVC 10-bit. So what you could to as a test, to see if your CPU can handle it, is go in Transcoding -> Advanced and disable the HEVC Decoder so that it tries decode in software but encode in HW. The CPU might choke or at least get pegged for a while.

Still would like to know what the devs have to say about the errors you got.

So I played around with the settings in advance. It seems to work fine with the vaapi option but not the quick sync.

i played a h.264 and move quick sync as the preferred transcode option and it went to software transcoding when I started playing. If I move vaapi up it started doing a hardware transcode.

[Happy2Play 9780]

Devs will probably need to see all logs, server, hardware_detection, and ffmpeg logs for specific example.  Also sounds like a device driver issue.

[mike3821 67]

Hopefully somebody can help or at least clear things up for me.

My googling is reporting possibly quicksync not being supported under linux? I'm not 100% sure on this.

[Q-Droid 989]

Well, you know VAAPI works for HW so until you get a definitive answer from the devs you can set that as the priority AND disable all h.265 (HEVC) decoders/encoders. This should stop delays in streaming and errors in the logs.

Both Quick Sync and VAAPI are using HW for encoding and decoding. I also noticed you're running a beta release of Emby which could explain some of the odd HW transcoding behavior.

 

[mike3821 67]

54 minutes ago, Q-Droid said:

Well, you know VAAPI works for HW so until you get a definitive answer from the devs you can set that as the priority AND disable all h.265 (HEVC) decoders/encoders. This should stop delays in streaming and errors in the logs.

Both Quick Sync and VAAPI are using HW for encoding and decoding. I also noticed you're running a beta release of Emby which could explain some of the odd HW transcoding behavior.

 

Okay. There is no options for encoding h.265 only for decoding. Likely a limitation of my hardware.