[mythtv-users] 60hz too slow for NTSC + Bob deint?

[Jesse Guardiani]

Doug Larrick wrote:
> Jesse Guardiani wrote:
>   
>> Hello,
>>
>> Is 60hz just too slow for NTSC + Bob deint?
>> Or is something lying?
>>
>> I get this when I try to play back NTSC video
>> on my LCD TV running 60hz:
>>
>> 2006-04-16 22:54:19.226 OpenGLVideoSync: x,y -> 720, 450
>> 2006-04-16 22:54:20.944 NVP: Timed out waiting for free video buffers.
>> 2006-04-16 22:54:21.338 Using OpenGLVideoSync
>> 2006-04-16 22:54:21.338 Set video sync frame interval to 33366
>> 2006-04-16 22:54:21.338 Video sync method can't support double framerate
>> (refresh rate too low for bob deint)
>> 2006-04-16 22:54:21.339 Set video sync frame interval to 33366
>> 2006-04-16 22:54:21.342 Using deinterlace method bobdeint
>> 2006-04-16 22:54:21.354 Using audio as timebase
>> 2006-04-16 22:54:21.354 Video timing method: SGI OpenGL
>> 2006-04-16 22:54:21.354 Refresh rate: 16697, frame interval: 33366
>>
>> 16697 > 33366 / 2 
>>
>> And according to vsync.cpp, that's a problem.
>> I something lying, or are those numbers correct?
>>
>>     
>
> Do you have a default timestretch factor turned on?

I think 0.19 comes with 100 as the default, which corresponds to 1.0 in 
livetv.


>   That can push the
> required refresh rate too high.
>
> But actually, 16697 corresponds to 59.89 Hz vertical refresh...

What's the math behind that?


>  this is
> fractionally less than the 59.97 that you actually need.  Sounds like
> you need to play around with your modeline.
>   

Ah. That might actually be it. I'm not using a modeline currently on 
that screen. Perhaps it's
autodetecting incorrectly? Would I be damaging my screen if I bumped the 
vertical refresh
slightly?

-- 
Jesse Guardiani
Programmer/Sys Admin
jesse at wingnet.net