[Interest] Video acceleration with gstreamer 1.0 omx and Qt 5.9.4 / 5.10 eglfs on RPI3 (brcm)

[Paolo Angelelli]

I did some research some time ago.

It seemed, back then, that the problem may have arised from the fact that
the sink glimagesink, that is the one that has to be used on the RPi, might
be built using mesa, but to have it run HW-accelerated, it should use broadcom's
egl.
So it might be you have to rebuild gstreamer for that.

But i'd be interested to know if that's really the case, and if so, whether
things work as expected once gstreamer gets properly rebuilt


On Wed, 31 Jan 2018 17:28:57 +0100
Petar Koretić <petar.koretic at gmail.com> wrote:

> Hi all.
> 
> So I haven't played around with this for some time but around one year ago
> or more I think I got this up running fairly easily. This was maybe still
> with gstreamer 0.10.
> 
> For the past two days I was trying to get video working with acceleration
> on the RPI player through QtMultimedia using QML Video element.
> 
> Using VC4 driver is a no go as there is no acceleration support in the
> driver yet as far as I know but the simple fullhd video played pretty
> nicely as far as it goes.
> 
> Anyway I went back the standard omx route.
> I tried to build and use Qt 5.9 creating a system using buildroot as I
> always do and later checking with latest raspbian stretch.
> Both methods compiled without issues using eglfs and gstreamer 1 and using
> the broadcom driver.
> 
> In the end these are the instructions that I decided to follow for rasbian
> http://www.tal.org/tutorials/building-qt-510-raspberry-pi-debian-stretch
> where I used gstreamer-omx-rpi package.
> 
> Playing example full hd video (
> http://cdn3.viblast.com/streams/hls/airshow/2670k/stream.m3u8) or any mp4
> youtube file results in a not so smooth video with obvious stutters
> (gpu_mem is at 256mb)
> .GST_DEBUG=omx:4 shows that the omx is being used.
> 
> I remember that I was able to play two videos at the same time (one full
> hd, one smaller) with animations without issues but I'm not sure if this
> was using eglfs and gstreamer 1.0 as it was more than a year ago.
> 
> Is this expected to work in this setup with gstreamer omx on rpi and
> broadcom driver using eglfs or which route should I go? Any help is
> appreciated as I've tried a fair bit of different things and I'm still
> trying but can't understand if this should be possible at all.
> 
> Best regards,
> Petar