Xvideo performance on Radeon 7500 vs Intel 915

Linxiao linxiao.li at gmail.com
Sun Dec 3 18:42:57 PST 2006

On 12/4/06, Roland Scheidegger <sroland at tungstengraphics.com> wrote:
> Linxiao wrote:
> > Hi, Roland:
> >
> >      NV's Xv also just converts planar yuv (YV12) to packed yuv (VYUY)
> > for display.
> > ( I have had a glimpse of nv_video.c in Xorg6.8.2/7.1.) And that
> > consumes CPU a lot,
> > especially when I use nv's blitter ports to play 16channels X CIF YV12
> > video stream
> > which each is created as an XvImage and played with XvShmPutImage.
> >
> >     Is there any existing patch for this? (I use nv 9550, and it should
> > support planar
> > yuv hardwarely.) If no, would you please provide any suggestion on
> > playing multiple
> > channels of video?
> what is nv 9550? Such a chip does not exist.

Sorry for my carelessness, and I have been messed with these graphics
card types these days. What I really mean should be nv's TNT2 not ati's

> Anyway, the nv driver handles video vastly different than what the
> radeon driver currently does. Instead of using a back-end scaler which
> is used directly at scan-out, it does a scaled, filtered blit (that's
> pretty close what a normal texturing operation does). I'm not convinced
> the blitter really could handle planar yuv directly, maybe you'd need
> something like a fragment shader to compose the final image back out of
> the three planes. The nouveau project might have some ideas how you
> could do that, or at least may in the future.

nouveau 's current nv_video.c seems to be just taken from Xorg's nv module,
and maybe I should dive into the other parts of it. And I would keep an eye
on that project.

Thank you for your advice and information.

> Roland

leal @ www.leal.cn

More information about the xorg mailing list