MLT
From Vague Hope Wiki
melt prj.xml -consumer avformat:prj.mp4 \ acodec=libmp3lame acodec=aac ab=128k \ vcodec=libx264 b=5000k acodec=aac ab=128k tune=film preset=slow
melt prj.xml -consumer avformat:prj.mp4 \ acodec=libmp3lame acodec=aac ab=128k \ vcodec=libx264 mlt_profile=atsc_1080p_25 vb=15M
melt prj.xml -consumer avformat:prj.mp4 \ acodec=libmp3lame acodec=aac ab=128k \ vcodec=libx264 mlt_profile=atsc_1080p_25 vb=15M apsect=16/9
see `x264 --fullhelp` for tune, preset params.