[mythtv] render2019 comments

[Klaas de Waal]

Test update after rebuilding just now:

2019-09-30 15:53:20.346755 C  mythfrontend version: devel/2019-render
[v31-Pre-1033-g04a2952975] www.mythtv.org

>
> > Test on my development system: Intel i7-7700, only built-in Intel
> > graphics (no Nvidia card).
>
> Is that a Kabylake processor? If so, the new VAAPI code has not been
> tested with Kabylake. It may be fine but I have come across
> differences with older chipsets (tested on Sandybridge, Ironlake and
> Coffeelake).

Yes this is a Kaby Lake according to the Intel website
https://ark.intel.com/content/www/us/en/ark/products/97128/intel-core-i7-7700-processor-8m-cache-up-to-4-20-ghz.html

>
> > Software: Fedora 30 with LXDE desktop.
> > Mythfrontend graphics setting: (Setup / Video / Playback / Current
> > Video Playback Profile) VAAPI2 Normal
> > Mythfrontend plays in a 1280x720 window on a 1900x1200 desktop.
> > Content is 50Hz but monitor is 60Hz.
> > This is for me the usual setting.
> >
> > Build: no problem.
>
> Is VAAPI enabled?

This is what the ./configure  says:
# Video Output Support
x11 support               yes
xnvctrl support           yes (system)
xrandr support            yes
VDPAU support             yes
VAAPI support             yes
NVDEC support             yes
Video4Linux codecs        yes
MMAL decoder support      no
OpenGL support            yes
OpenGL video              yes
OpenGL ThemePainter       yes
MHEG support              yes
libass subtitle support   yes

>
> > Mythfrontend startup error message:
> > [AVHWDeviceContext @ 0x1422d00] Failed to initialise VAAPI connection:
> > -1 (unknown libva error).
> > Cannot load libcuda.so.1
>
> As noted to John - there are some static checks that need cleaning up
> but in your case they should just be informative - not sure why the
> VAAPI check would fail if VAAPI is enabled though.
>
The message is still present.

> > Playback of recordings:
> > H264 1080i50, playback OK but jump back/forward shows one frame
> > out-of-order about 0.5 second after the start
This is present with playback profile 'VAAPI2 Normal' but NOT with
'VAAPI Normal'.
Jumping back and forth with playback profile 'VAAPI2 Normal' gives the
following messages:

2019-09-30 16:02:55.154076 I  Player(7): Waiting for video buffers...
2019-09-30 16:02:55.169912 N  GetNextFreeFrame() served a busy frame
A. Dropping. UL(au)UuALAuLUuuuuLLL
2019-09-30 16:02:55.179095 N  GetNextFreeFrame() served a busy frame
C. Dropping. UL(au)UuLuLULUuUuuLLu
2019-09-30 16:02:55.179114 N  GetNextFreeFrame() served a busy frame
C. Dropping. ULuUuLuLULUuUuuLLu
2019-09-30 16:02:55.504087 I  Player(7): Video is 3.07792 frames ahead of audio,

>
> If you have tearing in master and the branch - you definitely have a
> vsync issue.
>
> A quick google gave me this:-
>
> https://askubuntu.com/questions/240923/enable-sync-to-vblank-on-lxde-with-intel-video-card
>
> Otherwise try forcing sync to vbank from the command line (intel/amd
> driver environment variable) :
>
> vblank_mode=1 mythfrontend -v playback
>
The 'vblank_mode=1' did not make any difference, the first one will be
tested after the next reboot.
Agree that this has probably nothing to do with your changes.

Thanks,
Klaas.