[Mplayer-users] Re: new things in CVS

Dag B dag at bredband.no
Tue Jun 5 19:10:42 CEST 2001

Arpi wrote:
> Hi,
> > > send _now_ your feature requests (here, to the list, for discussion)!
> >
> > My request is about VSYNC-synchronization on the video output - for xv
> > output at least.
> ...
> >
> > What comments?
> current Xv API doesn't support vsync. at elast for ATI GATOS driver there
> is an option to enable double buffering with vsync. and i hacked G400 Xv
> driver and added this feature, but these are non-standard.

You managed to do this without hacking the kernel itself?
I read Alan Cox' diary at

The entry for April 7 says:
"I spent some time plotting with Jim Gettys about the right way to get
vertical blank support into the kernel and what synchronization methods are
needed between X and the audio layer. As with many conversations with Jim the
'We had that working fifteen years ago I guess we  should dig it out and make
it work in XFree' sentence appeared. It never ceases to amaze me how  much
the X11 folks had prototyped so far back. 

We do now have a plan for vertical blank drivers. This needs kernel support
as an interrupt has to be  handled before returning to user space otherwise
your machine locks up. It does appear possible that  we can generate a kernel
module by sticking an OS specific header and footer onto small generic per
card routines and a card table. That means the vblank driver can be generated
by the X people for multiple OS's. It also means that the vblank stubs for
each card can be maintained in the card drivers. "

> btw you can increase number of buffers in vo_xv.c first lines. it
> helps a lot but works only if you have enough video ram.

I guess you mean "offscreen videoram not allocated to DRI"...?

Dag B

Mplayer-users mailing list
Mplayer-users at lists.sourceforge.net

More information about the MPlayer-users mailing list