[mythtv-users] HD, the holy grail...

[Jarod Wilson]

On Wednesday 28 February 2007 08:09:00 jk-myth at kleeh.com wrote:
> > Some people have better luck that others, for whatever reason... A
> > 2.8GHz Xeon should be more than able to do 1080i. Hell, I had an
> > athlon xp 1800 at one point that could almost do it, as well as a
> > 1.5GHz core solo mac mini I was toying with a few days ago that could
> > almost do it. I have an athlon xp 2600 and an athlon 64 2900 that can
> > do 720p and 1080i playback without a problem. My current Athlon 64
> > 3500 frontend gets no more than ~40% busy playing back 1080i
> > material, and the clock speed rarely ramps up above 1GHz.
>
> I'm afraid I'm one of the people with bad luck ;) I have a very similar
> (frontend only) system: Athlon 64 3500, 6200 PCI-X, 1GB DDR-400.  When I
> watch HD my processor is pegged and I notice the video is a little jerky.
> I'm using the Nvidia proprietary drivers - I've tried a half-dozen
> different versions.  XvMC lowers the processor utilization but causes
> other issues with sound that make it unusable.  Besides a 3500+ should be
> enough even w/o XvMC correct?

Yep. I'm not using it at all in those numbers where my 3500 is no more than 
40% busy. Not sure what's amiss on your end, but something's definitely up...

> The only thing I have close to a theory is that my TV is a flat-panel -
> nvidia detects its native resolution of 1366x768 - and mythtv uses the
> native resolution for both 1080i & 720p.  Perhaps the additional burden of
> rescaling is the cause of some of my problems.

Highly doubtful. I run at 1920x1080p. 1080i stuff doesn't have to scale at 
all, but 720p does. 720p actually takes less cpu to play back.

> I've been trying to 
> configure xorg to output 1080i or 720p and forgo the rescaling but I
> haven't figured out the right modlines and override options yet.  I'm
> curious if anyone thinks my rescaling theory is valid or just a dead-end.

I think you're better off running at your panel's native resolution. The 
problem lies elsewhere. Just dunno exactly where... Is Xv actually enabled in 
your setup? Or is it possibly getting nuked due to the compositing extensions 
being enabled? Try a simple xvinfo and see that its actually enabled... If 
not, there are three lines to add to your X config...

-- 
Jarod Wilson
jarod at wilsonet.com