[MPlayer-users] Re: cropping & scaling

[D Richard Felker III]

On Fri, Jul 04, 2003 at 03:23:19PM -0500, Jonathan Rogers wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> andrea_meroni wrote:
> >this is my encoding command:
> >
> >mencoder -dvd 1 -ovc frameno -o frameno.avi -oac mp3lame -lameopts  
> >preset=128 -alang it  && mencoder -dvd 1 -ovc lavc -lavcopts 
> >vcodec=mpeg4:vbitrate=949:vhq:vpass=1 -vop scale=716:304,crop=716:432:2:70 
> >-oac copy -o /dev/null && mencoder -dvd 1 -ovc lavc -lavcopts 
> >vcodec=mpeg4:vbitrate=949:vhq:vpass=2 -vop scale=716:304,crop=716:432:2:70 
> >-oac copy -o they_live.avi
> >
> >
> >questions:
> >
> >1. why don't I get the film properly cropped? I mean that after encoding I 
> >still see the black bars as in the original dvd (and with the same size)
> >2. are the scale values correct (is it correct to use the crop-x-value to 
> >scale?)? or should I use 640:272? Where is the difference?
> 
> If the visible part of the original film frame is indeed 716x432, your 
> command appears correct. It would be a lot easier to attempt diagnosis 

Except that 716 is not divisible by 16, which is bad. You should scale
so both width and height are multiples of 16. Also 716x304 is probably
a bit big to get good quality at 950 kbit/sec, so 640x272 would likely
be a better choice.

Rich