[Openchrome-users] Much improved picture from TV out but intermittent sync problem

[Paul Gardiner]

Ivor Hewitt wrote:
> 
>>
>> There's a similar sounding problem mentioned in the Unichrome
>> TV out page. Is this known to be still a problem? I
>> read about the use of bobdeint as a cure. I can't do that
>> because my frontend doesn't quite have the grunt to run it
>> for all content. In any case, if I understand how bobdeing
>> works (which maybe I don't) then it wouldn't be a completel
>> cure, it would turn temporal missyncing into spacial missyncing.
>>
>>   
> you should be using bob-deinterlacing on mythtv for xvmc. it won't 
> require additional frontend grunt.

I wonder what's going on. If I use bobdeint with xvmc I get just a
few frames a second. If I use it with xvmc-vld then some content
works, but some hiccups. Any idea what I might be doing wrong?

Is this syncing problem understood now? I got the impression
from what I read that no one really knew why bobdeint fixes the problem.
The other strange thing is I have yet to see the problem when using
mplayer. So far I've seen it only with the MythTv internal player.
If it were a problem with the hardware or the driver, then it's
surprising that mplayer doesn't fall foul of it.

I read something about bobdeint, in effect, doubling the frame
rate (copying the lines of one interlace into the missing ones
beteen them). If so I can sort of see how that would prevent
temporal reordering, but instead it would swap the interlaces
spacially. I guess I must be wrong though because I couldn't
see any ragged diagonal edges when I tried it.

Is there anything I can read on the use of frame buffers in MythTV?

Paul.