[mythtv] Aspect ratios and non-linear stretching

[Sean McVeigh]

Okay, so I've come up with a decent algorithm which works in-place doing 
a 1-d cylindrical projection (will probably add parameters to configure 
the projection angle and resampling).
I'm using a LUT to precompute the transform, and was wondering, are 
mythtv filters ever informed about changes to the size of their input 
frames?  Does the filter get re-loaded, or is this a run-time thing that 
will have to be detected on the fly.. ie.  if(current size != previous 
size){ recompute lut } ?

As a filter, there will be a loss in picture information due to the 
pre-squeeze of about 25% in the center of the screen, but it will 
probably suffice for now I guess.  Maybe I'll take a stab at allowing 
the filter API to return frames with different geometries, or finding a 
clean way to work it in near the Show() code.  (problem being 
maintaining another frame pool -- it's my understanding that we don't 
new and delete actual frame->buf's on the fly... right??)

Cheers,
Sean
> Do it as a filter. You can see how filters are enabled and disabled
> at run-time by looking at the deinterlacing code. It's messy but
> it's this should be improved in the mythtv-vid branch in the next
> few months.
>
>