[MEncoder-users] 2pass: auto-calculation of bitrate?

[Ilya Zakharevich]

[A complimentary Cc of this posting was NOT [per weedlist] sent to
RC 
<mencoder-users at mplayerhq.hu>], who wrote in article <20071012225616.223c58e1.cooleyr at gmail.com>:
> On Sat, 13 Oct 2007 04:12:45 +0000 (UTC)
> Ilya Zakharevich <nospam-abuse at ilyaz.org> wrote:
> 
> > D) And now the last logical step: If of these 99 remaining videos 40%
> >    is "action-like", 40% is "arthouse-like", and 20% is animation,
> >    then law of big numbers starts to be applicable.  Essentially, I
> >    won't need to have summaries of the particular videos; I could feed
> >    in 40 copies of "average action-like summary", 40 copies of
> >    "average arthouse-like summary", and 20 copies of "average
> >    animation summary".

> This is certainly not workable.  There is no average "action" movie.

For the purposes at hand, obviously there is.  Just catenate 1000
randomly chosen action movies together.  ;-)

> In fact, trying to classify the visual complexity of movies by
> loosely defined genres is a good sign you don't understand what
> you're doing.

Do not feel any need to apologise.

> There will be movies that are ridiculously easy to compression, and
> there will be some that are incredibly difficult to compress. 

Irrelevant.  These will be averaged together...

> A huge number of factors will determine this, and genre is really
> the most minor one of them, and won't help you at all.  The brand of
> film, type of camera, etc., will be much greater factors.

A reasonally working 35mm photo camera is approximately equivalent to
6..8megapixel digital camera.  After removing "dead pixels", the image
is good enough to saturate capabilities of about 4MP "presentation image".

It is natural to expect that a reasonally working 35mm movie camera
would capture enough info to present in 2megapixel frames (probably
more, taking into account temporal "noise cancellation") - taking into
account the (ridiculously small) frame size.  If so, it would largely
exceed the capacities of DVD-like media.

So, as far as it is 35mm film and a decent cinematographer, I do not
think the camera would matter a tiny bit...

Thanks,
Ilya