[MPlayer-users] -ovc copy changes aspect?

[D Richard Felker III]

On Tue, Jan 11, 2005 at 08:03:37PM +0100, Josef Wolf wrote:
> On Tue, Jan 11, 2005 at 03:55:06AM -0500, The Wanderer wrote:
> 
> > >I just did the following in the hope that only audio would be
> > >compressed and video would be left as is:
> > >
> > >mencoder in.avi -oac mp3lame -lameopts q=0:vbr=0:aq=0 -ovc copy -o out.avi
> > >
> > >But for some reason, this changes aspect ratio.  Is this by intent?
> > 
> > Unless I'm very much mistaken, the only way this could possibly change
> > the aspect ratio is if the original AVI contained an "aspect" header
> > (specifying what aspect to play with) and the output AVI does not. Since
> > nothing but MPlayer pays any attention to the "aspect" header AFAIK, if
> > this is the case the two files should have the same aspect ratio if
> > played back in another player.
> 
> Ummm... I find this something wired, because I created this file from a VDR
> recording with mencoder: 
> 
>    mencoder 001.vdr -oac copy -o in.avi \
>       -ovc lavc -lavcopts vcodec=mpeg4:vqmin=2:vhq
> 
> Then I noticed that I accidentally forgot to compress the audio.  To avoid
> compressing the whole video a second time, I decided to use "-oac copy".
> 
> Now the wired thing is that the _first_ mencoder (which actually _did_
> video compression) preserved the aspect as it was while the second
> mencoder (which should just copy the video) changed it.

i don't know what the problem is here, something very strange. but
look up all the aspect-related options in the man page and you should
be able to find a way to make it work. alternatively, post a proper
bug report with full verbose output from mencoder and mplayer so we
can see where the aspect is getting messed up.

rich