[MPlayer-users] SkipFrame/Duplicate Frame

[Arpi]

Hi,

> Skip frame messeges mean that mencoder has dropped a frame, either to keep the
> he
> audio syncronized or because of a 3:2 pull down removal.  If this is true is
it shouldn't happen for pulldown if user specified the exact -ofps

> there a way to tell mencoder to encode every frame regardless of the audio
> sync?  
yes. -mc 0

> Duplicate frame messages on the other hand are information meaning mencoder
> found a duplicate frame, but is happily encoding it (whhich would show up as
> jerky pans in the video).
nope. it means mencoder duplicated a frame to keep a-v sync or requested
-ofps

> If duplicate frame messages are seen, that is probably an indicator that the
> header is lying about the contents of the file (i.e. its saying 29.97 fps, and
> nd
> its really 23.976 encoded data) meaning the -ofps switch should be used to do
> o
> a 3:2 pulldown removal.  
yes

> So when doing 3:2 pulldown removal you'll see lots of skip frame messages,
> reporting that mencoder is actually doing the removal.
> 
> What does it mean when you tell it -ofps 23.976 and it doesnt actually display
> ay
> more than a handful of skip frames?

there are 24 frames encoded per second, but if you left the original 30fps
it have to duplicate every 5th frame to keep it. if you usedf -ofps 24 it
means it shouldn't skip/dup frames to keep fps.

> How does mencoder actually do the removal, is it smart enough about the field
> d
> encoding to remove the appropriate fields, or does it just whack a whole
> frame?  (How does this work with deinterlace post processing?)
whole frame. it works for pulldown


A'rpi / Astral & ESP-team

--
Developer of MPlayer, the Movie Player for Linux - http://www.MPlayerHQ.hu