[MEncoder-users] about filmdint/pullup

[Peter Cordes]

vdmsss wrote:
>Hello. I have been playing with filmdint. My main source are films  
>broadcast on DVB at 50i, and since most tutorials and discussions  
>around are based on NTSC, and I am left with some doubts:

>       Can filmdint (or pullup) be used to convert from 50i to 24p?

 The only reason you want to convert FPS is so it matches tutorials?  Don't
do that.  PAL is usually much easier, because it's almost never telecined,
just sped up, so you can just skip the parts of tutorials that deal with
maybe needing to inverse telecine.

 There are filters to make sure the field order is right in PAL video. 
-vf phase  can swap fields if your film looks combed.  That reminds me, I
added some hysteresis to -vf phase a while ago in an attempt to get a Star
Trek PAL DVD to look reasonable, but it's an NTSC->PAL conversion from the
hard-telecined source for special-effects scenes, so it's all crappy.
I should post the patch somewhere, since it did seem to help.

 Anyway, if you really really want to convert frame rate, none of the video
frames have to change, you just need to stretch the audio to match the
framerate.  There are ways to filter audio to change the length without
changing pitch.  Maybe look for a LADSPA filter to do that.  Or avidemux can
do it, I think.  Probably audio editors like audacity can, too, but then
you'd have to dump the audio to .wav and manually edit it.

 I still say you shouldn't, unless you have a really good reason (like a TV
that only syncs to NTSC frame rates).

-- 
#define X(x,y) x##y
Peter Cordes ;  e-mail: X(peter at cor , des.ca)

"The gods confound the man who first found out how to distinguish the hours!
 Confound him, too, who in this place set up a sundial, to cut and hack
 my day so wretchedly into small pieces!" -- Plautus, 200 BC