[mythtv] Ticket #4872: Detect if video is letterboxed and switch to corect fill mode

[f-myth-users at media.mit.edu]

    > Date: Wed, 19 Mar 2008 09:14:20 -0400
    > From: Daniel Kristjansson <danielk at cuymedia.net>

    > Also, if the code is clean and well compartmentalized it makes it
    > easier to add support for it in the commercial detector later on.

Just as a thought to whenever things like this make it into the commflagger:

I currently don't commflag on sources which don't have commercials
(e.g., PBS, movie channels, etc), but there are plenty of opportunities
for good stuff that could be done via the commflagger or something hooked
off of it (not just aspect ratios, but detecting too many bad/blank/static
frames, no audio, etc etc---I and others have mentioned these in the past).

So I'm hoping that when/if the commflagger is augmented to handle
these sorts of things, there will be some recognition that it might
be run in order to do all these other ancillary things but -not-
to detect commercials.  I'd suggest (at that point) changing its
name to something else ("general content-dependent postprocessing"
is terrible---someone, please come up with a snappy alternative :)
and having "actually try to detect commercials and stick skiplist
info somewhere" be just another checkbox along with "detect bad
video" (with suboptions for how) and "detect missing audio" and
so forth.

That way, all the other mechanisms used by the current commflagger
are available, but recordings that are known a priori to -never-
have commercials won't have the possibility of spurious tagging
from false positives in the commflagger per se.  (And it -might-
mean the flagger will run faster, but I suspect it might have to
do most of the work for other reasons anyway---and anyway, it probably
has to at least read the whole file, which is its own overhead.)