[mythtv-users] Video offset with black bars when using JudderFree / UseVideoModes=1

Open Media Support support at openmedia.co.nz
Sat Jun 10 05:02:20 UTC 2017


I've been trying to get an new frontend to frame rate switch cleanly, but
I'm getting the video vertically displaced by 50-100+ pixels when I turn
on UseVideoModes=1.

At first I thought it was an issue with VAAPI but I've reproduced the
issue on a clean environment using software decode.

So far I've collapsed the issue down to two calls to VideoOutWindow:: 
with odd values.

Here is some output from mythfrontend -v playback

Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext tv_play.cpp:5856 (StartPlayer) TV::StartPlayer(): Created
player.
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext tv_play.cpp:2532 (HandleStateChange) TV::HandleStateChange():
Changing from None to WatchingPreRecorded
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext videooutwindow.cpp:560 (PrintMoveResizeDebug) Display Rect 
left: 213, top: 0, width: 1493, height: 1200, aspect: 1.60759
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext videooutwindow.cpp:569 (PrintMoveResizeDebug) Video Rect   
left: 0, top: 0, width: 720, height: 576, aspect: 1.25
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext tv_play.cpp:2632 (HandleStateChange) TV::HandleStateChange():
Main UI disabled.
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext tv_play.cpp:424 (StartTV) TV::StartTV(): Entering main
playback loop.
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext mythplayer.cpp:2193 (SetBuffering) Player(3): Waiting for
video buffers...
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext mythplayer.cpp:2284 (CheckAspectRatio) Player(3): Video Aspect
ratio changed from 1.25 to 1.77778
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext videooutwindow.cpp:560 (PrintMoveResizeDebug) Display Rect 
left: 0, top: 57, width: 1920, height: 1085, aspect: 1.60759
Jun 10 14:49:09 mythfe-1604 mythfrontend.real: mythfrontend[5855]: I
CoreContext videooutwindow.cpp:569 (PrintMoveResizeDebug) Video Rect   
left: 0, top: 0, width: 720, height: 576, aspect: 1.77778


1st time due to
 - HandleStateChange between 2532 and 2632

2nd time due to
 - VideoOutWindow::VideoAspectRatioChanged

At some point display_video_rect.top has been changed to 57

I don't have a full debug enabled stack this days so I'm not sure what the
call tree is to invoke MoveResize from within HandleStateChange().

For some reason enabling UseVideoModes=1 is causing some interesting side
effects and I have no idea why we're going from

Display Rect  left: 213, top: 0, width: 1493, height: 1200, aspect: 1.60759
to
Display Rect  left: 0, top: 57, width: 1920, height: 1085, aspect: 1.60759

Especially as my display is set to 1920x1080.

I've also had a look at the settings for the frontend and I can't see
anything obvious.

Any pointers to debug this further would be greatly appreciated as there
are a number of historical emails around the same problem
 -
​http://lists.mythtv.org/pipermail/mythtv-users/2012-October/340787.html
 -
​http://lists.mythtv.org/pipermail/mythtv-users/2010-September/296624.html

Steve


More information about the mythtv-users mailing list