Xv performance and quality issues at 1920x1080/60 resolution

[Jason Keirstead]

> It probably only applies to OpenGL rendering, not XVideo. Something like
> Alex's changes above would be necessary to prevent tearing with textured
> XVideo.

No I don't think so... it is not tied to any rendering method. Docs say this:

There are two mechanisms to sync to VBlank under XOrg.  OpenGL has the
GLX_SGI_video_sync extension, and DRM has DRM_IOCTL_WAIT_VBLANK .  One
or both of these works
on most modern hardware.  Both of these are useable for video output
-- MythTV, for example,
will select whichever is available.


>> > As long as dri gets enabled, I don't think there's much you can do.
>> > Though if the bottleneck is the cpu, it might help if the driver could
>> > do planar video instead of converting it to packed.
>> > What content are you playing back? In particular, if this is some h.264
>> > content coming from some DVB stream using xinelib to decode, xinelib (at
>> > least released versions) might not be able to use both cpu cores to
>> > decode, a X2 6400+ will likely indeed be too slow in this case. If that
>> > isn't the problem, I'm not sure if the gpu could really be too slow -
>> > sounds unlikely (though for maximum gpu performance you'd want to make
>> > sure you're using dual channel memory).
>>
>> I do have dual channel memory ( 2x1 GB ). The content is over DVB but
>> it is not H.264 - it is MPEG2 @ 1080i . The CPU is not th ebottleneck
>> - if I pop in another video card the box can process the video no
>> problem.
>
> Option "DMAForXv" "off"
>
> might make a difference (for better or worse :) for you here.
>
>
> --
> Earthling Michel Dänzer           |          http://tungstengraphics.com
> Libre software enthusiast         |          Debian, X and DRI developer
>
>



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