[MPlayer-users] Embedding video aspect in mpeg1

[Rich Felker]

On Thu, Nov 10, 2005 at 06:19:14AM +0800, Heimdall Midgard wrote:
> While playing around with encoding to VCD-compliant mpeg1, I
> discovered a quirk with the aspect options used to embed the
> video's width-to-height ratio.
> 
> Both "-lavcopts aspect=4/3" and "-mpegopts vaspect=4/3"
> appear to produce video with the correct aspect when played
> by mplayer, but *NOT* when played by other free software
> players, namely VLC and Xine.
> 
> VLC and Xine apparently interpret the aspect as something
> closer to 16/9 (squished). The command I use is:
> 
> mencoder -oac lavc -ovc lavc \
> -lavcopts acodec=mp2:abitrate=224:\
> vcodec=mpeg1video:vbitrate=1150:vrc_buf_size=327:\
> vrc_minrate=1150:vrc_maxrate=1150 \
> -of mpeg -mpegopts format=xvcd:vaspect=4/3 \
> -vf pullup,softskip,scale=352:240,harddup \
> -af resample=44100 -ofps 24000/1001 \
> -o output.mpeg input.avi
> 
> I know there's a note in the man page for "-lavcopts
> aspect=" that "only MPlayer will play these files correctly,
> other players will display them with wrong aspect." Does
> this apply to "-mpegopts vaspect=" as well?

No, it applies only when used with avi container. For mpeg container
the aspect should always work in all players.

Rich