[gentoo-user] xorg-server update causes horizontal line in movies

[gentoo-user] xorg-server update causes horizontal line in movies

[Grant]

After I updated to the latest xorg-server this weekend, I started
noticing that movie playback has a horizontal line across the middle
of the screen that kind of looks like the image is broken.  It always
shows up when there is a lot of on-screen movement.  A flash makes it
very visible.  It looks like one half of the screen is moving a litle
slower than the other half of the screen.

It happens in totem, mplayer, and vlc and mplayer terminal output
confirms that I am using xv.  I'm using nvidia-drivers and I've tried
the masked version with no luck.  Has anyone else seen this?

- Grant
-- 
gentoo-user@gentoo.org mailing list

[gentoo-user] Re: xorg-server update causes horizontal line in movies

[Sven Köhler]

[-- Attachment #1: Type: text/plain, Size: 946 bytes --]

> After I updated to the latest xorg-server this weekend, I started
> noticing that movie playback has a horizontal line across the middle
> of the screen that kind of looks like the image is broken.  It always
> shows up when there is a lot of on-screen movement.  A flash makes it
> very visible.  It looks like one half of the screen is moving a litle
> slower than the other half of the screen.
> 
> It happens in totem, mplayer, and vlc and mplayer terminal output
> confirms that I am using xv.  I'm using nvidia-drivers and I've tried
> the masked version with no luck.  Has anyone else seen this?

That's due to the lack of vertical synchronisation.

The graphicscard sends the picture to your monitor. While that happends,
in the middle of the movie-picture, the movieplayer switches to the next
frame of the movie. The result: you see the upper half of frame N and
the lower half of frame N+1


Greetings,
  Sven


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 251 bytes --]

Re: [gentoo-user] Re: xorg-server update causes horizontal line in movies

[Grant]

> > After I updated to the latest xorg-server this weekend, I started
> > noticing that movie playback has a horizontal line across the middle
> > of the screen that kind of looks like the image is broken.  It always
> > shows up when there is a lot of on-screen movement.  A flash makes it
> > very visible.  It looks like one half of the screen is moving a litle
> > slower than the other half of the screen.
> >
> > It happens in totem, mplayer, and vlc and mplayer terminal output
> > confirms that I am using xv.  I'm using nvidia-drivers and I've tried
> > the masked version with no luck.  Has anyone else seen this?
>
> That's due to the lack of vertical synchronisation.
>
> The graphicscard sends the picture to your monitor. While that happends,
> in the middle of the movie-picture, the movieplayer switches to the next
> frame of the movie. The result: you see the upper half of frame N and
> the lower half of frame N+1

Yeah, that's exactly what it looks like.  I tried specifying HorizSync
and VertRefresh in xorg.conf and also a Modeline, but they don't seem
to make any difference.  I got the data from my TV's EDID data.
Modeline, HorizSync, and VertRefresh are all defined under the monitor
section of xorg.conf right?

Section "Monitor"
      Identifier "monitor"
#      HorizSync 31-83
#      VertRefresh 56-85
      Modeline "1360x768" 86.96 1360 1480 1528 1774 768 778 783 817
-Hsync -Vsync
EndSection
Section "Screen"
      Identifier "screen"
      Device "device"
      Monitor "monitor"
      DefaultDepth 24
      SubSection "Display"
              Depth 24
              Modes "1360x768"
      EndSubSection
EndSection

- Grant
-- 
gentoo-user@gentoo.org mailing list