[MEncoder-users] Choppy video when changing framerate

[Phil Ehrens]

Wolfgang Woehl wrote:
> Donnerstag, 14. Juni 2007 20:07 Phil Ehrens:
> > Stanley wrote:
> > > Manuel Carro wrote:
> > > >     Using the -ofps option makes the video to definitely look choppy.
> > > > And it is not a question of the player itself: the same video (after
> > > > reducing the framerate) looks choppy when using mplayer, xine, totem,
> > > > etc.  I assume that, to go e.g. from 25 to 20 (my current benchmark)
> > > > -ofps could remove one out of each five frames.  But, when playing
> > > > back, it looks as if those removals were not happening evenly, but
> > > > rather in groups every second or so.  I do not think mencoder is doing
> > > > that (is it?).  Any hint of what could be the problem (and the
> > > > solution)?
> > >
> > > I have the same feeling too. The video does look choppy more or less
> > > after changing FPS, especially reducing FPS a little bit (e.g. 25fps to
> > > 24fps).
> > > I think this is somehow unavoidable without rendering all frames again
> > > which will bring much computation. As the interval of frames changes,
> > > the content of frames must be changed in order to look really smooth.
> >
> > Exactly. Except in cases where ivtc works perfectly, reducing framerate
> > is a lossy process. Transcode's modfps clonetype 3 (pixel interpolation)
> > can produce very good results, however, and is a clever and elegant
> > solution.
> 
> Could you post an example line for like converting a 30fps.avi (mpeg) to a 
> 25fps.avi? I tried and I don't get it. Yes, after reading 
> README.filter.modfps :\ Thanks in advance.

This is not the appropriate forum for doing that.
Please make the request in the transcode-users list.