[mythtv] Patch to autodetect 4:3 Zoom aspect ratio

[Petr Stehlik]

Mårten Bohlin wrote:
> Hi!
> 
>  I have written a patch for the release-0-20-fixes branch (svn
>  revision: 16162) that detects black bars on the top and bottom of the
>  frames. When that is detected it toggles to "Letterbox 4:3 Zoom". And
>  if no bars is detected it toggles back to "Letterbox Off".
> 
>  I have only used it for a couple of days, so I guess there will be
>  some more tweaking to get it perfect.
> 
>  Comments are welcome.

This is very cool. Though the zoom modes changed a bit in 0.21 but that 
will make it even easier probably. Great would be to extend this to 
detect also black bars on left and right sides for automatic half and 
full zoom on 16:9 displays :-)

Petr