[mythtv] VAAPI2 improvements

[Andreas Mayer]

On 07.11.2018 20:42 Peter Bennett wrote:
> There are some further improvements that will reduce CPU usage with 
> VAAPI2. Please try the latest master commit 
> (9d627fe9eec3aca85e7ae62ada8f04b2cf26fc83) and see if it helps.
I have tried the latest commit yesterday with LiveTV and the test video 
using mythavtest, VAAPI2 works even better now (but VAAPI playback is 
still a bit smoother, although with VAAPI I'm getting sometimes a black 
flashing screen, I guess because of some frame flips not in sync with 
vsync).

With VAAPI/avsync2 and -v playback I see repeating lines during playback:
Player(0): dropping frame to catch up, lateness=51000 usec

With VAAPI2/avsync2 and -v playback I see repeating lines during playback:
Player(0): Waiting for video buffers...
Player(0): dropping frame to catch up, lateness=48000 usec

For VAAPI2 FE cpu went up to 90%, intel_gpu_top shows: render busy 60% 
GAM 85% CS 55% TSG 40% VFE 40% GAFS 20%
So both cpu and gpu show higher utilization now.

I have tried with display 1920x1080 at 50 and 3840x2160 at 30 (HDMI 1.4)

I will continue testing VAAPI2/avsyc2 with LiveTV (SD, HD and UHD) using 
3840x2160 at 30 to see if this configuration works stable now (I think I 
noticed audio not starting yesterday sometimes).

Andreas