Re: Mencoder

[csj@mindgate.net]

On Fri, 7 Feb 2003 21:39:50 +0200,
Sergey A. Ovchar wrote:
> 
> Hi.  I'm recently encoded from VideoCD's(2cd) to divx, using
> command:
> 
> mencoder -vcd 2 -ovc lavc -lavcopts vcodec=mpeg4 -oac copy -o bla-bla-bla.avi
> 
> I know - it was my mistake about -oac (at that moment I didn't
> have lame).  When I trying play theese files under M$98
> platform, it says "I can't load codec..."  And the video's
> playing without sound :-(((

Try installing the proper codec. Amazing that M$ can't play the
unecumbered mp2 format.

> The command:
> 
> mencoder bla-bla-bla.avi -ovc copy -oac mp3lame -lameopts vbr=3 -o bla-bla-bla-new.avi
> 
> helps, suond appears, and size of files a bit smaller, but sum
> of sizes 1.avi and 2.avi is larger than blank CD-R capacity
> (approx. 740m)
> 
> The VideoCD's already returned to it's owner :( And I can't
> give them again :(((((((((((((
> 
> How can I encode from *.avi to smaller *.avi

Re-encode the video with a smaller bitrate? That would involve
putting in something like:

-lavcopts vcodec=mpeg4:vbitrate=${KBPS}

$KBPS would be something within the range of 1800 to 250. IIRC
the MPlayer default is 800.

Unless the soundtrack is more important, I think it might make
more aesthetic sense to reencode the audio instead:

-lameopts vbr=3:br=96

I'm assuming that the MPlayer -lameopts default to 128 or 160, in
which case the savings should be enough to jam the avi into a
CD-R. 

An alternative is to split the avi. The options to play around
with are:

-ss Start_Time_in_Seconds -endpos Length_of_Cut_Part_in_Seconds

Note that -ss is relative to the original video, while -endpos is
an offset from -ss. BTW, you can easily buy 90-min or 800 MB
CDR's and spare yourself all the trouble.

> And how can I unite two *.avi's from different CD's into one
> whole avi (for recording to cd) ?

The easiest way to do it under GNU/Linux:

http://fixounet.free.fr/avidemux/

The following also reportedly works:

cat *.avi | mencoder - -forceidx -oac copy -ovc copy -o fused.avi

I've never tried it because avidemux answers all my simple
editing needs.