On Tue, 23 Jul 2002, Guido Fiala wrote:
> > I'm not sure if someone said this already or not, but the XvPutVideo simply
> > displays incoming analog video into the drawable specified in the
> > XvPutVideo call (some setup and configuration calls are req'd previous to
> > calling XvPutVideo() ).
>
> Thanks! That sounds really like i'am doing something wrong using repeated
> calls of XvPutStill() every 40ms (PAL). So it would work to just call
> XvPutVideo() once. I thought i made it right, as xawtv and mplayer both do
> use Still. I tried just to use Video() but it did'nt display anything at all.
>
> Do you have sample code working as described?
>
> > moving YUV across the bus, but it should use no CPU.
>
> Yes, so i thought. But that would mean, that the XServer loads it's data
> directly from the v4l device itself (mmap-io or direct write into AGP-memory?)
> The latter should work if the ximage is a contigous array in AGP memory only.
>
> > All-in-Wonder Radeon 8500 DV with the GATOS drivers. Also, if you load the
> > v4l module in your XF86Config-4, you will be able to use the XvPutVideo
>
> I did load the module and hence xvinfo prints out information on XvPutVideo()
> but still no result.
>
> > call on a video4linux device installed in your machine. If anyone knows of
>
> I tested it with bttv and dvb cards, botht did'nt work as expected, just with
> XvPutStill()
>
> (The v4l-dvb drivers are available at linuxtv.org, maybe someone can find a
> hint in the driver itself)
>
> Can it be, that whether V3K (or VxK) nor Matrox nor NVIDIA can do this?
>
The V4L module in XFree86 coordinates with V4L in the kernel to
have the video data dumped directly to the framebuffer. In the most
simple case it dumps RGB data into the visible framebuffer. Pretty
much all XFree86 cards should support that. In the case of some
drivers (NVIDIA and Matrox and others) V4L is told to dump the
video to offscreen video ram and then the graphics card driver
overlays it with HW scaling and filtering. When you call XvPutVideo
it puts data from an XvPort (the TV card's output in this case) into
a window. The server automatically handles cliplist changes,
obscured windows, etc... There should be little if any CPU
involvement.
Mark.
_______________________________________________
Xpert mailing list
[EMAIL PROTECTED]
http://XFree86.Org/mailman/listinfo/xpert
