Raspbery Pi 3 Transcoding with OMX

[DFWjih3rt7h 0]

HI, I wondered if anyone had any info on transcoding on the pi 3 (latest raspbian)? I was previously running Plex (not in Docker) which transcoded a 1080p h264 file to lower bandwidths fine in real time, i suspect 1 stream would have been the limit though. I love Emby and am very happy with the switch in general. I'm looking to use the OpenMAX OMX hardware transcoding and am running the armv7_neon Docker image. At the moment it's not able to transcode even 1 stream in real time, it's running at about 0.4x. I try turning the hardware decoding and encoding on but they get disabled again.

 

Does anyone have any advice? Do I need to run Emby without Docker? Do I need to provide a custom ffmpeg? I can't find any definitive info on how to get this working. Looking in the transcoding logs I can't see any info on omx in the ffmpeg config text so I guess this is the issue?

 

Apart from this issue Emby runs great on the pi3 and it's an ideal low-power Emby box for when you're mainly direct playing.

 

Any advice greatly appreciated.

 

Thanks

Edited August 24, 2018 by DFWjih3rt7h

[Luke 37095]

We're not currently providing omx in the ffmpeg build, but it's possible for the future. In the meantime there is vaapi that you can try. thanks.

[tdiguy 96]

We're not currently providing omx in the ffmpeg build, but it's possible for the future. In the meantime there is vaapi that you can try. thanks.

No more user specified ffmpeg for the rpi builds?

[Luke 37095]

it's not in the ui. you could launch emby server with your own custom command line if you really want to.

[Luke 37095]

What's wrong with vaapi though?

[tdiguy 96]

Ok that's good. So the options are to custom compile your own ffmpeg ( I had a post somewhere on here on the flags I used ) or to use vaapi. If you use mpeg2 you might want to buy the license from rpi to unlock hardware acceleration.

 

I found this here article which might be useful: https://github.com/legotheboss/YouTube-files/wiki/(RPi)-Compile-FFmpeg-with-the-OpenMAX-H.264-GPU-acceleration only thing i would say is that it would be up to you if you want to run the make install command that will install ffmpeg which isnt really needed unless you want to be able to just use ffmpeg by typing ffmpeg without a path.

 

So I guess to properly answer, at least in my opinion ( and i am no pro mind you ) you will probably benefit the most from making a custom compiled ffmpeg then launch emby with the custom command. Then of course go into emby and enable hardware transcoding for openmax.

If you use mpeg2 its also worthwhile to buy the licence from the raspbery pi org to unlock mpeg2 hardware acceleration.

 

Sent from my moto g(6) play using Tapatalk

Edited August 26, 2018 by tdiguy

[Luke 37095]

Yes correct.

[tdiguy 96]

What's wrong with vaapi though?

if this article: https://trac.ffmpeg.org/wiki/HWAccelIntro is correct, there is no vaapi support for a rpi. Only hardware acceleration for the rpi is mmal and openmax.

[Luke 37095]

Ok I didn't realize that, thanks.

[DFWjih3rt7h 0]

Thanks all, I looked into vaapi and came to that conclusion, that it's not available on the raspberry pi. My next step was to look into building ffmpeg with mmal and OMX. The system ffmpeg looks to be built with support but it's a v3 not v4 version and not built statically which I think rules out using it? I tried building a docker image which copied it in overwriting the provided one but it didn't work. I couldn't find any static binaries suitable for arm with the right support. I then looked at building it but was having trouble getting it built so I stopped there for a bit. It's good to hear I'm on the right lines so I'll look at it again. Thanks for everyone's assistance.