[mythtv-users] Watching HD streams on a SD set

[R. G. Newbury]

George Nassas wrote:
> On 3-Oct-07, at 7:20 PM, Enigma wrote:
> 
>> The frontend in question is has onboard Intel
>> 915G graphics using the i810 driver.
>>
>> Also, does anybody know if Myth supports XvMC for this device?  The  
>> wiki
>> only mentions Nvidia and ATI cards but the driver documentation  
>> seems to
>> indicate that the driver supports XvMC.  Has anyone successfully  
>> used this?
> 
> It's not myth that has to offer the support but rather the driver.  
> The i810 doesn't right now but the intel people are committed to  
> doing so by the end of the year.
> 

Firstly, you *do* need myth compiled with xvmc support. If you build 
from SVN, just enable all of the video choices, and let configure decide 
which you can do!
Re drivers:

 From the man page for the i810 driver:
        Option "XvMCSurfaces" "integer"
        This option enables XvMC.  The integer parameter  specifies  the
        number  of surfaces to use.  Valid values are 6 and 7.  Default:
        XvMC is disabled.

Now I notice that the Xorg.0.log says something to the effect that the 
XvMCSurfaces line is ignored, and then the i810 driver seems to use xvmc...
However, on my box, I have now noticed that if I re-boot (which I try 
not to do, but this is a new buildup) the Xserver sometime does not 
start, and the system creates a new xorg.conf *using the intel driver*. 
Same Option line is required for that driver, plus 'Option "LinearAlloc" 
"6144" for HD. The intel driver works on my box, but it is using ffmpeg 
decoding. From Xorg.0.log:

2007-10-03 22:19:19.167 VideoOutputXv Error: XvMC output requested, but 
is not supported by display.
Xlib:  extension "XVideo-MotionCompensation" missing on display ":0.0".
2007-10-03 22:19:19.168 XvMCSurfaceTypes::find(w 1280, h 720, chroma 1, 
vld 0, idct 1, mpeg2, sub-width 0, sub-height 0, disp, p<= 88, 730 <=p, 
port, surfNum)
2007-10-03 22:19:19.168 Trying XvMC port 73
....

So maybe *both* of them don't do xvmc?  That is clearly not correct, so 
something is going on...And the mythbox still records, and plays, so I'm 
not touching it until the weekend!

Geoff