VIDEO_MPEG1="-vcodec mpeg1video"
VIDEO_MPEG2="-vcodec mpeg2video"

ffmpeg -i polyphon.ogv -vf "drawtext=text='mpeg1.mpeg':fontsize=72:fontcolor=yellow, scale=352:288" $VIDEO_MPEG1 -vb 1024k -ab 128k -y polyphon-mpeg1.mpeg || exit 1
ffmpeg -i polyphon.ogv -vf "drawtext=text='mpeg2.mpeg':fontsize=72:fontcolor=purple, scale=720:480" $VIDEO_MPEG2 -vb 2048k -y polyphon-mpeg2.mpeg || exit 1