[mythtv-users] Horizontal seam in picture - contradicting EDID

David Engel david at istwok.net
Fri Jul 18 15:37:59 UTC 2008


On Fri, Jul 18, 2008 at 09:26:09AM -0400, Dan Wilga wrote:
> For what it's worth, I get something similar at 1080p or 1080i on my 
> Sony TV using HDMI. I am using OpenGL vsync, so the tear doesn't 
> move; it's always in the exact same location, and of consistent 
> shape. Unfortunately, I don't have another display device I can use 
> to see if it's the TV or the PC that's at fault.

It's a timing issue with th PC.  Basically with OpenGl vsync and HD
content, Myth and the nvidia graphics driver can't finish updating the
display before the blanking interval ends.

The best solution found so far for me and others is as follows:

  Enable the "UseEvents" option in the X server.

  Enable all "Sync to VBlank" options in nvidia-settings.

  Use RTC frame timing in Myth.

This will result in an occasional skipped or doubled frame due to the
RTC timing not being exactly in sync with the VBI but there shouldn't
be any tearing.

David
-- 
David Engel
david at istwok.net


More information about the mythtv-users mailing list