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

[Isaac Richards]

On Wednesday 09 March 2005 03:33 pm, Jeroen Brosens wrote:
> > 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.

But it does - myth also supports getting the vsync info through the DRM 
interface.  What 'new ideas' are you stirring up?  I mean, it's obvious that 
you don't know what you're talking about, but other than that, it seems like 
you're just whinging to me.

> 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.

No, I don't agree that it 'diminishes compatability' at all.  There's nothing 
nvidia specific in either the drm or opengl vsync methods.  

If the driver for a particular video card doesn't provide certain services, 
such as, oh, providing a method to know when the next vsync will be, there's 
absolutely nothing that I can do about it.

> 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.

Err, the vbi device would be input, not output.

Isaac