[MPlayer-users] cutting with mplayer/mencoder

[Alain Barthélemy]

Le vendredi 30 avril 2004, 11:45:30 ou environ Alexei Khlebnikov <a.khlebnikau at sam-solutions.net> a écrit:
> On Thu, 29 Apr 2004 10:06:58 -0700 (PDT)
> Loren Merritt <lorenm at u.washington.edu> wrote:
> 
> LM> On Thu, 29 Apr 2004, Alexei Khlebnikov wrote:
> LM> 
> LM> > On Thu, 29 Apr 2004 16:11:02 +0300
> LM> > marianciuc <marianciuc at home.ro> wrote:
> LM> >
> LM> > > How I cut  an  *.avi file , with mplayer/mencoder in two parts: first from
> LM> > > beginning to 01:20:30 time , and second from 01:20:30 to end of  avi file ??
> LM> >
> LM> > man mplayer for switches -endpos and -ss
> LM> 
> LM> No, don't use -endpos / -ss for splitting avis. -ss seeks to the next
> LM> I-frame after the specified time, while -endpos ends exactly at the
> LM> specified time. So you can lose up to several seconds of video if you
> LM> split that way.
> LM> 
> LM> A tool that works (finds I-frames and splits at an appropriate location)
> LM> is avisplit (comes with transcode).
> 
> Note that because of that, avisplit is not as precise as mencoder.
> 
> I personally prefer avisplit for cutting large movies, because it can split
> multi-audio AVIs without loosing additionl audio tracks and it better
> handles buggy divx5 movies. Though on some movies it fails too.
> 
> Also I prefer to cut the way that the first 5 seconds of the second part
> are the same as the last 5 seconds of the first part. It reminds about
> what the first part ended with after a disk change and makes
> transition between 2 (or more) disks psychologically "smoother"
> while viewing the movie. It also eliminuates inconviniences with cutting
> at the middle of the phrase.

Personaly I use avisplit too. The only problem is with a/v sync as seen with
tcprobe -i my_movie.avi

Thus I have to do transcode -i in.avi -P1 -N** -y raw -o out.avi

to have the same number of audio and video chunks.

I don't know of a way to avoid that disparity between audio and video chunks
(with mencoder).

-- 
Alain Barthélemy
cassandre at bartydeux.be
http://bartydeux.be
Linux User #315631