[Kwintv] The importance of good video hardware and drivers

[George Staikos]

On Tuesday November 05 2002 13:34, Stefan Hellwig wrote:
> >    AGP is definitely being used since it's an AGP card. :-)  As for the
> > AGP mode, I don't know what it's set at right now, but it certainly is
> > using agpgart.
>
> Well, that's not the case here. I've read somewhere that there are
> conflicts between agpgart and NVidia's own implementation. That can be
> activated by an option in XF86Config. Mine looks like this:
>
> Section "Device"
>   BoardName     "GeForce 2 MX"
>   BusID  	       "1:0:0"
>   Driver  	       "nvidia"
>   Identifier	       "Device[0]"
>   Option            "NvAgp" "1"
>   Screen        	0
>   VendorName    "Nvidia"
> EndSection

  Hm I'll check on this.  I did see agp messages in dmesg though, so that 
leads me to believe that it is using it.

> >     I would be interested if you could try all 5 V4L output methods,
> > plus the Xv plugin, and see what your results are for each.
>
> OK, I tested this all now (with overlay enabled all the time). The first
> two (XVideo) worked but I think that the XVideo plugin still produces the
> better picture quality, with V4L I still have a "ripped" TV picture when
> there is some movement on the screen. And it seems to be slower than
> XVideo.

   It should definitely be slower.  The ripped qualities I just don't see, but 
I can believe they exist.  It would be interesting to see what 16bpp is like.  
How does grab display mode work for you in xawtv?  Is it better?

> The two X11 settings did not work, I always get two very green and small TV
> pictures next to eachother. QtVision then crashed and I had to manually
> edit my qtvisionrc to get it to start again...

    The crash is not good.  Did you get a backtrace?  It's a bit tricky to 
debug that chunk of code since it is multithreaded and has events flying all 
over the place.

   The small green pictures are expected because there is no colourspace 
selection done yet.  It's hardcoded to yuv422.  I'm doing this code now but 
I'm doing it very slowly.  It's not a high priority, and I have some 
particular requirements in mind.

> > Maybe QtVision is driving more than usual PCI traffic and causing similar
> > problems for you.
>
> Hm... I am not sure. Shouldn't I have the same problems with the XVideo
> plugin as well?

   Yes, so that is not the case.

-- 

George Staikos