[mythtv-users] Experiences with XvMC

[Scott]

On Aug 1, 2005, at 9:17 AM, Donavan Stanley wrote:

> On 7/31/05, Scott <catfather at donpoo.net> wrote:
>
>>
>> I had two issues that for me are critical.
>>
>> When using xvmc with Xine none of the OSD overlays would work. This
>> meant no on screen information, subtitles, or closed captions during
>> playback. I didn't investigate this to much however I think it could
>> be worked around. One possibility seems to be with the Xine xxmc
>> support.
>>
>> XvMC appears to do very simple one-field deinterlacing in hardware.
>> Xine 1.1.0 has experimental XvMC bob deinterlace support which I
>> enabled and saw some improvements. I compared various DVD (480i
>> content) scenes played via Xv with Xine deinterlace post processing
>> and XvMC with hardware deinterlace. It was pretty clear to me that Xv
>> with deinterlace post processing was producing a much better picture
>> than XvMC using hardware deinterlacing.
>>
>
> You know, you *might* want to test with Myth instead of Xine since
> neither of those issues apply to Myth.

I'm assuming by 'Myth' you are referencing the Myth Internal video  
player? For 480i DVD playback using xine seemed like a valid test to  
me as I was able to directly compare the same source material via two  
different display methods. I gather what you're suggesting is that I  
should have also used the Myth Internal video player with xvmc  
support and compare the results against xine + xv.  Honestly, I  
didn't think to try the Internal video player because it seems most  
people, including myself, use Xine for DVD playback to get DVD menu  
support.

Is there technical documentation on how the Myth Internal video  
player uses XvMC along with any other post processing filters?  
(Besides the source code, of course!)  I've seen posts to the list  
suggesting that when using XvMC with Myth it's best to also disable  
the deinterlace option in Myth as well as the two could conflict.  
Does this sound accurate to you and does that mean that Myth + xvmc  
relies strictly on the xmvc deinterlace routines in hardware?

It may be possible that the Myth Internal video player with xvmc can  
provide better quality deinterlace and post processing than Xine +  
xv. Obviously a deeper understanding of how Myth works with xvmc and  
more objective tests are needed.

--
Scott <catfather at donpoo.net>
AIM: BlueCame1