[mythtv-users] nvidia tv-out passthrough to pvr350 s-video-in?

[Michael T. Dean]

Thomas Börkel wrote:

> Sascha Uelpenich wrote:
>
>> John Kuhn wrote:
>>
>>> your using matthias X driver and your playback is poor? after 
>>> loading that driver all my divx playback is flawless on my 667mhz 
>>> PII box..
>>
>> Yes, it only works with mplayer's -framedrop option. If I do not use
>> this parameter it's like slow motion... And watching movies w/
>> -framedrop is not satisfying.
>>
>> I tried the "new" ivtvdev driver that comes w/ recent versions of
>> ivtv-1.1.10pre (I think starting with pre99m or so) and with this one
>> divx playback was even slower. In addition, I cannot see any performance
>> difference when using mplayer with "-vo xv"
>
Because the PVR-350 drivers do not support the X Video extension.  
Therefore, MPlayer is silently (but gracefully) falling back to a non-Xv 
video output driver (most likely X11).

>> or with "-vo ivtvosd". The
>> only difference is that movies with "-vo ivtvosd" only cover the upper
>> two thirds of the screen. "-vo ivtv" does not show any video, only sound
>> works.
>
> You have to use "-vo x11"!

Right.  To use Matthias's X Windows driver or Chris's update to 
Matthias's driver (both called ivtvdev), you have to specify the x11 
video output driver for MPlayer.  This results in displaying the video 
on the On-Screen Display (OSD) framebuffer of the PVR-350, not the video 
underlay (but on top of it).

The ivtvosd driver is an MPlayer driver that pipes an input MPEG stream 
through to the PVR-350's MPEG decoder, which outputs the video on the 
video underlay through the PVR-350's TV out.  Although this sounds like 
the best way to play DVD's, it actually has several problems.  There are 
some pretty serious A/V synchronization issues, and it only works with 
certain DVD's.  Therefore, you're probably better off with using 
MPlayer's x11 driver to write to the ivtvdev X Windows driver.

The -vo ivtv option doesn't work because MPlayer has no video driver 
called ivtv.

If the info in this thread doesn't get you where you want to be (i.e. if 
using ivtvdev with MPlayer's -vo x11 isn't acceptable quality for 
DVD/DivX/XviD playback) and you still want to try taking advantage of 
your nVidia card's Xv support using ivtv passthrough, let me know.  
There are some things that can be done to make it work, but you'll have 
to do some (not just a little) development work and use Chris's bleeding 
edge drivers.  Also realize that this means that you would be unable to 
watch a DVD or other video (DivX, XviD, MOV, AVI, etc.) while recording 
something and vice versa (since passthrough occupies the PVR-350).  You 
would still be able to record while playing back a show that MythTV 
recorded because it would be playing directly on IvyTV (so it wouldn't 
require ivtv passthrough).

HTH.

Mike