[mythtv] [PATCH] OSD glitch - starts as 4:3 and corrects to 16:9

Matthew Wire devel at mrwire.co.uk
Thu May 24 22:39:05 UTC 2007

On Fri, 2007-05-25 at 08:21 +1000, Matt Doran wrote:
> Daniel Kristjansson wrote:
> > On Thu, 2007-05-24 at 23:45 +1000, Matt Doran wrote:
> >   
> >> It wasn't the constructor.  It took me a while to figure out how the 
> >> video playback process works ... but I got there eventually.  :)    In a 
> >> method in NuppelVideoPlayer called OpenDummy which sets up the dummy 
> >> video while waiting for the channel to tune....  it sets the video size 
> >> arbitrarily to 720x576 and aspect of 1.3333.  At this point we don't 
> >> have access to the display size.  We don't know that until in the 
> >> InitVideo method.
> >>
> >> So my fix was to set the force the video aspect to the display aspect if 
> >> we're in dummy mode.  It works very nicely.  Now when I start to watch 
> >> live tv, the OSD appears at the full width (16:9).  I don't get the 
> >> ugliness of switching from the default 4:3 to 16:9 when the video starts.
> >>
> >> The patch was only a couple of lines, and it results in much more 
> >> polished results. :)   
> >>
> >> What do you think?
> >>     
> >
> > It looks like a decent enough hack. It will still chose the
> > wrong video aspect ratio whenever you view a non-16:9 stream
> > on a 16:9 screen, but at least it will default to filling the
> > screen for 16:9 screens so it's an improvement. What I would
> > like to see down the road is some intelligent guessing as to
> > the aspect ratio. If we are about to view channel X and the
> > last time we viewed it the resolution and aspect ratio were Y,
> > then we should start with Y when we start on channel X. If we
> > are using xrandr we really want to minimize these changes.
> >
> > Can you open a ticket with your hack?
> >
> >   
> Will do.
> I realise it was a bit of a hack.  When the dummy video is setup we 
> don't have access to the display dimentions, so had to adjust the aspect 
> when we're initialising the video.
> My theory was that it's no worse than we've got now.  It's also a hack 
> to assume you have 4:3 display, so I figured we may as well use the 
> aspect of the display as a best guess.   I'm in Australia, where all our 
> DVB broadcasts are 16:9.  So this works nicely for me.
> I realise it could be smarter, but it's a start.  ;)
Maybe a better option would be to add a database setting for screen
aspect ratio.  Would have to be a per-frontend setting but I can't
imagine it changing very often once it's set.

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