[pvrusb2] PAL-Plus support

[Carsten Meier]

Am Fri, 7 Nov 2008 09:35:42 -0600 (CST)
schrieb Mike Isely <isely at isely.net>:

> On Fri, 7 Nov 2008, Carsten Meier wrote:
> 
> > Hi,
> > 
> > I think you misunderstood me a little bit. Just to be sure we're
> > talking about the same thing: http://en.wikipedia.org/wiki/Palplus .
> > I know, that my PVRUSB2 doesn't have any decoder-hardware.
> > 
> > To assemble a true 16:9-picture of a PALPlus-broacast, only the
> > lines hidden in the black letterbox-bars have to be reinserted into
> > the picture. Can that be done with the PVRUSB2?
> > 
> > Regards,
> > Carsten
> 
> This sounds like you are talking about what would otherwise by a
> normal broadcast but in anamorphic format.  In that case the thing
> that "adds" the "black bars" would be the device that actually
> displays the image, not the mpeg encoder.

No... come on guys, read the wikipedia-article. A PALplus picture
starts as an anamorphic picture (to take advantage of the full
line-count), then every 4th line gets dropped to restore the aspect
ratio for non-palplus-devices. The dropped lines are transmitted hidden
(don't know how they are hidden) in the black bars on the top and the
bottom of the picture. A PALplus-decoder gets those hidden lines and
reinserts them into the picture so that you end up with an anamorphic
picture which can then be viewed as 16:9 with full line-count.

To non-palplus-devices the picture looks like a normal 4:3 letterboxed
picture (but it actually isn't)