[mythtv-users] Intel hd 4000 support

[Stephen Worthington]

On Tue, 14 May 2013 08:32:08 +1200, you wrote:

>On Tue, 2013-05-14 at 05:49 +1200, Stephen Worthington wrote:
>> On Mon, 13 May 2013 10:16:02 -0400, you wrote:
>> 
>> >On 05/13/2013 03:13 AM, Stephen Worthington wrote:
>> >> On Mon, 13 May 2013 14:54:23 +1000, you wrote:
>> >>
>> >>> On 13 May 2013 13:18, Rajil Saraswat wrote:
>> >>>
>> >>>> Hi
>> >>>> I am in the market looking for an uktrabook which is easy to carry around.
>> >>>> Most ultrabooks use intel hd 4000 graphics card. How well does mythtv
>> >>>> support it? Does it provide hardware acceleration similar to vdpau?
>> >>
>> >Tearing--as opposed to dropped frames or "stuttery" playback--is 
>> >generally caused by either bad video drivers or improper video driver 
>> >configuration and has nothing to do with the CPU's ability to keep up 
>> >with video decoding demans.  All of our video rendering methods (Xv, 
>> >VA-API, OpenGL, and VDPAU) rely on the video card drivers to proper 
>> >video sync, which will prevent tearing.  Most drivers require the user 
>> >to explicitly enable sync--and often separately for Xv vs OpenGL/VDPAU.
>> >
>> There is no sign at all of dropped frames or anything like that.  On
>> an i7 CPU, 2.33 GHz gives you a lot more CPU than the speed suggests.
>> My thought was that the tearing was as a result of the deinterlacing,
>> as it seemed to only happen on interlaced HD H.264 video.  It could
>> easily be a bug in the deinterlacing software somewhere, but I tried
>> all the options I could find and none of them made any difference. The
>> tearing was just in a small strip close to the top of the screen, and
>> it came and went with screen content, as I would expect for a
>> deinterlace problem.
>> 
>> Should anyone have any useful suggestions about this, I would be happy
>> to test them out.  All I have to do is adjust a couple of settings in
>> mythfrontend to switch between VAAPI and CPU modes.
>> 
>> >Again, the drivers need to provide support for color adjustment (and/or 
>> >"studio mode" and such).
>> >
>
>> >
>> There is no way to just use the Nvidia drivers directly as the Nvidia
>> hardware is off by default and needs to be turned on, and the BIOS
>> does not support swapping the hardware so that Nvidia is on and HD4000
>> is off.  Nor does Bumblebee or any other software I have found.  I
>> would love to be able to just enable the Nvidia GPU as the default and
>> run the Nvidia drivers only, but it is not possible.
>> _______________________________________________
>
>A 1st gen atom can play OTA SD H264 & core2duo requires 50% CPU to play
>OTA HD H264 (yadifx1) so it is almost unbelievable that latest iCPU can
>not cope easily ..
>
>That tearing is probably from composite effects manager.
>Can disable it for full screen applications or try to get it to sync
>properly.
>There is a config tool for intel driver "driconf".

Thanks, I was not aware of that.

>Do you find mythtv & vaapi plays interlaced material at the right
>speed ?

Yes, it does seem to play at the right speed on the few TV programs I
have tried so far.  I have only 25 fps recordings, so I will have to
try some DVDs and downloaded video for other frame rates.  I think I
have a few video files that are strange frame rates I can try.

>VDPAU uses blitter if composite effects are active & then there's no
>guarantee for "no tearing".
>VDPAU is guaranteed to not tear if using overlay method.
>
>nVidia stated months ago that they were planning to support optimus in
>linux..
>http://www.phoronix.com/scan.php?page=news_item&px=MTM2MzQ

I think I have found out where the tearing is coming from.  The
database on the laptop has been around for a while and several MythTV
versions.  The "Paint engine" setting was set to Qt, which it had
inherited from earlier versions without my ever revisting the choice.
When I installed the working VAAPI drivers, it did not work on Qt and
I set it to OpenGL, again without really thinking about the options -
it was in someone's post that it was needed.  Today, I did a bit more
testing and could not get the tearing with the playback profile set to
"High Quality", as was happening before.  But when I then changed the
paint engine setting to back to Qt, the tearing and darker colours
were back again.  So now I have set the paint engine to "Auto" (I
think that must be a new option), and it seems to be using OpenGL with
the High Quality profile and the screen output is excellent.  No
tearing, correct colours.

There are also lots of new options for deinterlacing too - I will have
to experiment with them.  It looks like I have enough CPU, as
expected, to run Yadif 2x happily.  Just how good that would be for
running on battery is something I will need to work out.