MLT
From Vague Hope Wiki
melt prj.xml -consumer avformat:prj.mp4 \ acodec=libmp3lame acodec=aac ab=128k \ vcodec=libx264 vb=15M acodec=aac ab=128k preset=slow apsect=16/9
melt prj.xml -consumer avformat:prj.mp4 \ acodec=libmp3lame acodec=aac ab=128k \ vcodec=libx264 vb=15M acodec=aac ab=128k tune=film preset=slow apsect=16/9
melt prj.xml -consumer avformat:prj.mp4 \ acodec=libmp3lame acodec=aac ab=128k \ vcodec=libx264 mlt_profile=atsc_1080p_25 vb=15M
see x264 --fullhelp
for tune, preset params.