[MPlayer-DOCS] [PATCH] update the mencoder telecine docs

[D Richard Felker III]

On Fri, Feb 18, 2005 at 11:31:32PM -0800, Corey Hickey wrote:
> Corey Hickey wrote:
> > It's been a while and the telecine howto I wrote is out of date. Here's
> > a patch.
> > 
> > * Added instructions for pullup,softskip.
> > * Removed description of pullup's shortcomings (just use softskip).
> > * Instructions to use "." for frame-step.
> > * A few clarifications.
> > * One grammatical fix (I think).
> > 
> > -Corey
> > 
> 
> I just realized that I should be using 24000/1001 in my examples instead
> of 23.976. For that matter, 23.976 is used througout the mencoder
> documentation.
> 
> If 24000/1001 is indeed correct, then all the docs should be updated.
> Instead of just 'sed -i s:23.976:24000/1001:g mencoder.xml' it would
> probably be nice to explain where all the weird numbers come from,
> either in our own words or by linking to an external page.
> 
> I'll do the work, except that I really don't understand it myself and I
> couldn't dig anything up on google. Can somebody explain it to me or
> give me a URL?
> 
> Thanks,
> Corey

My understanding is that 60000/1001 is just the only rational number
within the range of tolerance of the NTSC refresh clock, without
having a ridiculously huge denominator. Thus it was standardized as
the "official" refresh for NTSC with the advent of digital video.
30000/1001 and 24000/1001 are just the refresh converted from fields
to field-pairs or telecined frames.

I'm sure you can find better references on this somewhere if you
like...

Rich