ffmpeg -y -i ed_short.mp4  -i ed_long.mp4 -filter_complex_script mux_test.txt -map_metadata -1 -sn -c:a aac -ac 2 -ar 48000 -c:v libx264 -profile:v main -preset veryfast -level:v 51 -g 60 -bf 0 -crf 20 -loglevel info -f flv output.flv

