[mythtv-users] Can't get XvMC compiled in MythTV

Chad masterclc at gmail.com
Thu Apr 19 04:55:57 UTC 2007


> nVidia and Intel have both implemented MPEG-1 and MPEG-2
> acceleration using the XvMC standard for a number of years.
> The OpenChrome guys have not yet implemented either XvMC MC
> or IDCT acceleration, i.e. the acceleration methods in the
> standard. They have implemented something called VLD
> acceleration, which works with most, but not all, MPEG-2
> streams. MythTV supports this OpenChrome acceleration, but
> it is not actually XvMC. It has enough in common with XvMC
> that we call it "xvmc-via" internally.

That's interesting information, thanks.  I thought OpenChrome had a
version of XvMC, Xine also uses it's "version" of it, again, my vague
understanding.

> I have read that Intel is working on some new acceleration
> architecture which will work with the MPEG-4 codecs and
> possibly some of Microsoft's video codecs. The XvMC
> standard has defines for MPEG-4 and H.263, but no vendor
> supports this and unless Intel decides to use XvMC for
> their acceleration API it is unlikely that anyone will.
> XvMC is an extension of XVideo which has a problematic
> interface; it is very Microsoft Windowsy, which means
> the design allows one program crash can prevent you from
> using your hardware until the video driver is reloaded.
> So hopefully any future video API for Linux and other
> Unixes will abandon XVideo to correct the problems.
>
> -- Daniel
>
> _______________________________________________

As for the Intel stuff, I follow the Xorg list a bit and thought that
they hadn't implemented XvMC, but is that just for the newer chipsets
then?  Or am I misreading, or misunderstanding the discussions?  I
seem to remember reading something about XvMC being "on their list"
but wasn't high priority because of the processors that usually are
teamed up with the newer chipsets.  So because a decent Core Duo is
able to decode HDTV, no real 'need' for XvMC for the general populous,
thus low priority.

All just my meandering reading so please feel free to correct or clarify.

Thanks!

-Chad


More information about the mythtv-users mailing list