[mythtv] 4:3 Zoom code changed?

[Christian Hack]

> -----Original Message-----
> From: mythtv-dev-bounces at mythtv.org 
> [mailto:mythtv-dev-bounces at mythtv.org] On Behalf Of Edward Wildgoose
> Sent: Thursday, 13 November 2003 12:49 AM
> To: Development of mythtv
> Subject: RE: [mythtv] 4:3 Zoom code changed?
> 
> 
> > > I think someone changed the 4:3 zoom code recently?  The behaviour
> > > seems to have changed anyway.
> > 
> > Yeah, that was me.
> > 
> > Previously, the code was useless on 16:9 sets, which is why 
> I changed  
> > it.  Currently the three modes are:
> > * 4:3: fullscreen on 4:3 set, pillarboxed (shrink in X) on 16:9 set
> > * 16:9: letterboxed (shrink in Y) on 4:3 set, fullscreen on 16:9 set
> > * Zoom: Zoom (grow both X and Y) by 4/3
> 
> Yep, It's the last which is causing me trouble.  A thought 
> occurs.  You didn't expand by 4/3 instead of 3/4 did you?
> 
> > The first two change the aspect ratio, the third maintains 
> it while  
> > scaling.  This third one should be what you want.  At least 
> that's the  
> > intent.  Is this not what you're seeing?  What's the aspect 
> ratio of  
> > your TV, the entire video, and the active portion of the 
> video; and the  
> > pixel dimensions for all three?
> 
> Basically I have a 4:3 telly, but the BBC insist on 
> broadcasting everything in 16:9, but when it actually is a 
> 4:3 broadcast then the 16:9 picture has black bars down the 
> left and right (as well as the letterbox  ones on the top, ie 
> black border all around)
> 
>  __________
>  |  ____  |
>  |  |___| |
>  |________|
> 
> However, when I use the zoom mode then the screen is expanded 
> left/right to fit the picture, but the height is expanded by 
> significantly more than a proportionate resize and the 
> top/bottom are cut off, and people become tall and thin.
> 
> Does that make sense?

Perfect sense. I added the code for just that. I'm not right on the
bleeding edge of CVS at the moment so I haven't seen what has been done
to it. 

What my code did was assume the image was 16:9 and took a 4:3 chunk out
of the middle which was then scaled up to full screen.

There was a mode called 4:3 which would take an image and stretch to the
full screen. So for a 16:9 image it would just stretch vertically. I
assume this was for 16:9 TVs which would then stretch it out
horizontally. That way you don't waste precious lines.