Video tearing on the lower third of the screen

[amlopezalonso@…]

Hi,

Since upgrading to trunk I'm experiencing mild (just a couple of lines) video tearing on fast movements located somewhere in the lower third of the screen. Video hardware is Intel GMA X4500 (G43 chipset), using xserver-xorg-intel driver. This happens regardless of using ffmpeg+XVideo or OpenGL.

I'm providing the output of mythfrontend -v playback.

Regards, Antonio

[amlopezalonso@…]

mythfrontend -v playback output

[markk]

Did you upgrade anything else at the same time?

With your setup, the DRM video sync should take care of all sync to vblank for OpenGL and XVideo - and that hasn't changed since 0.24.

So my best guess would be that either your driver version was changed at the same - and it is now broken in some way - or perhaps the composite extension is now enabled.

Failing that, it may always have been tearing and there is a timing difference between your previous version and master that just makes it more obvioius/visible.

[amlopezalonso@…]

Yes, I upgraded the whole distro (Mythbuntu). I followed your guesses and found that desktop compositing was enabled (not so obvious as compositing effects in XFCE are not that prominent) so disabling it has fixed the problem. Thank you!

I guess this ticket is invalid unless you are planning to make MythTV compositor-compatible.

Thanks again!

[markk]

Antonio - thanks for feeding back. As I understand it there should be settings somewhere to force the compositor to use sync to vblank for fullscreen windows, although I've never tried it. The recommended configuration for MythTV is to disable the composite extension - not only to avoid issues such as these but also to maximise performance.