Intel QSV not working with ffmpeg

[neptunepic 11]

Hi all, I'm new to Emby so forgive me if this has been solved already. FYI I have Emby Premiere.

 

I'm running server on an i5-5200U and HD5500 graphics, which both support Intel QSV hardware transcoding.

HOWEVER, I'm noticing that when I enable QSV in Emby, ffmpeg seems to crap out midway through the transcode making the resulting file unplayable.

 

I'm running latest versions of all software including drivers.

 

Can someone help me troubleshoot?

[Luke 42080]

Hi there, we're sorry to hear about. First, welcome to the Emby community and thank you for supporting us. Can you please provide the information requested in how to report a media playback issue? 

 

Also, this feature is still experimental (as mentioned in the interface), therefore some patience will be required.

 

Thanks !

[neptunepic 11]

Hi, attached is the log from the most recent test I did, which yielded an incomplete unplayable MP4.
 
Thanks for your help!

 

 

Log.txt

Edited March 29, 2017 by neptunepic

[Luke 42080]

Well that log didn't even use quicksync, are you sure it's enabled?

[Swynol 375]

@@neptunepic

 

what version of ffmpeg are you using? i use this one https://ffmpeg.zeranoe.com/builds/ works well with QSV you need to also point emby to the folder to use this version rather than the default one

[Luke 42080]

@@neptunepic

 

what version of ffmpeg are you using? i use this one https://ffmpeg.zeranoe.com/builds/ works well with QSV you need to also point emby to the folder to use this version rather than the default one

 

That's only for windows. He is on linux.

[neptunepic 11]

Hi all, attached is the transcode log from my most recent test.

Can someone take a look and see if Quick Sync is working?

 

Log.txt

[Luke 42080]

Yes it is, looks like you're good to go.

[neptunepic 11]

Ok great! No idea what I did bit at least it's working.

Can you show me what to look for in the logs to know it's working?

[Luke 42080]

Just search for the presence of 

qsv

Notice it appears both before and after the file path being converted. This means quick sync is being used both to decode the existing file as well as to encode to the output.

[neptunepic 11]

Just discovered that with QSV enabled, WTV files (from windows media center) will not play back.

Looks like ffmpeg loads, then closes immediately.

Disabling QSV solves the problem.

Log attached.

 

Also, enabling VAAPI works fine with WTV files. Not sure about the other hardware accel options.

 

Log.txt

[Luke 42080]

Thanks for the report.

[neptunepic 11]

Luke, SHOULD it be working or is this a known bug?

[Luke 42080]

Hi @@neptunepic, at this time remember that GPU encoding is an experimental feature. As such, we don't yet have the answer to every possible issue. Even on the ffmpeg side this is still relatively new, and the Quick Sync encoder and decoder are not going to be as mature as libx264. It could very well be an issue within ffmpeg, from past experience wtv files have had more issues than any other video container.

 

As these types of things come up, we are all working together here in the community to decide the best course of action. Depending on input from others we may just want to disable the feature for WTV, although if it works with some files then we certainly don't want everyone to miss out on it. And additional experimentation may also lead to a defect being filed on the ffmpeg bug tracker.

[neptunepic 11]

Thanks Luke for the info.

 

All my testing so far shows that for whatever reason, ffmpeg fails to transcode all WTV files when QSV is enabled. I have had no issue with any other file types.

Assuming others have experienced the same, would it be possible to bypass QSV for WTV files only, allowing users to still take advantage of QSV acceleration for other formats?

[Luke 42080]

Yea I think there's a good chance that that's the direction we'll be headed in.