[mythtv] is there any chance to include these changes ?

Daniel Kristjansson danielk at cuymedia.net
Thu Sep 13 17:16:41 UTC 2007

On Thu, 2007-09-13 at 09:31 +0200, marek wrote:
> thx Daniel, look at my tickets #3958 & #3959 (vertical distortion and volume check against 14488)
> > Isn't being able to open the device more than once a V4L2 requirement?
> > i.e. can the driver be fixed instead of hacking MythTV for this?
> I think this is possible (maybe I doing sth. wrong) but I haven't so much time for this now - 
> a little Mythtv "hacking" was faster - box is connected in my living room and my wife sometimes 
> wants to record something from tv so she can't wait when the things are done ;)
> but I'll check this - as I say this is very early stage - but why don't use a chip (saa6752hs) 
> when it is possible and gives better video, less processing power and less diskspace than recording 
> analog with RTJpeg (on P4-1.8/256MB mythbackend eats abt 60-65% cpu when using standard PAL res.)?

I've put #3959 in my queue.

> > That sounds similar to 16:9 Stretch mode, i.e. it's a distorting
> > zoom. This may be accepted, but, as is, this patch won't apply
> > to mythtv-vid because zooming and aspect ratio modifications have
> > been split apart. Create a separate ticket for this enhancement.
> yes, it's something like this but without changing picture width. useable when (like me) 
> have a 16:9 analog tv configured in mythtv as 4:3. 
> new patch against 14488 (after splitting - I made these changes yesterday) included in trac.

If you're using a 16:9 TV you need to set the display dimension to 16:9
in your xorg.conf. There is a bug when Xinerama is enabled and you only
have one screen, but Issac has a patch for this which I assume he'll be
applying soon. i.e. I don't think you actually need this hack.

> I have a question : 
> how (and where) video devices (/dev/videoX) are validated in mythtv-setup - 
> eg. setting as PVR-x50 shows only /dev/video1 (which is v4l2 analog device) and 
> can't see /dev/video2 (mpeg + v4l2 - modified by me) - so I must change it manually ?

The VideoDevice class in libs/libmythtv/videosource.cpp has a driver
parameter, currently we set this to "ivtv", but we should probably
treat this string as a regular expression and use "(ivtv|saa6752hs)"
on line 1299 instead of "ivtv".

I'm assuming "saa6752hs" is the name of the driver as returned by
CardUtil::GetV4LInfo() in cardutil.cpp

-- Daniel

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