[mythtv-users] How I got great quality TV-out on my nVidia MX4000

Jeroen Brosens jeroen at fotoniq.nl
Wed Mar 9 20:33:35 UTC 2005

> On Wednesday 09 March 2005 02:06 pm, Jeroen Brosens wrote:
>> I'd like to add that I'd like to challenge the MythTV dev-people to
>> review
>> the Xv/XvMC code regarding the handling of vsync while using bobdeint.
>> One needs hardware with OpenGL support to have a Vsync to get bobdeint
>> working without going out of sync now and then (horrible jittering
>> occurs)
>> and that isn't good news for users of a barebone with built-in graphics
>> that can't support that, like myself (using an ASUS Pundit).
> Well, how do you expect it to know when to flip the buffers, if the video
> card
> can't tell it accurately?  Magic?
> Isaac

No Isaac, just something else than GL Vsync. I am not venting my
frustrations upon people either, rather just stirring up some new ideas on
this. Afterall, this is MythTV, Linux, Open Source... where meeting
challenges is the fun of everything! I also could have installed Windows
MCE and to be 'just a regular user on the safe side' but I want to be able
to participate in meeting the challenges where I can.

What I understand now is that all of the devvers use nVidia, can you agree
that this diminishes compatibility regarding video-related
functionalities? I am not a C++ developer you know; if I were I would have
tried to fix the problems myself but I can't.

Now on topic; am I talking plain nonsense when I ask whether the VBI
device can be used for Vsyncing? What I know is, that it is used for
teletext data and 'walks' in sync with the video fields so maybe that is
an alternative for using GL vsync.

-- Jeroen

More information about the mythtv-users mailing list