commands

> ./jblooper.sh 01_Engarrafado.mp3 cooper2-cut.mp4 eng.mp4

output:

ffmpeg version 3.2 Copyright (c) 2000-2016 the FFmpeg developers
  built with Apple LLVM version 8.0.0 (clang-800.0.42.1)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/3.2 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --disable-lzma --enable-vda
  libavutil      55. 34.100 / 55. 34.100
  libavcodec     57. 64.100 / 57. 64.100
  libavformat    57. 56.100 / 57. 56.100
  libavdevice    57.  1.100 / 57.  1.100
  libavfilter     6. 65.100 /  6. 65.100
  libavresample   3.  1.  0 /  3.  1.  0
  libswscale      4.  2.100 /  4.  2.100
  libswresample   2.  3.100 /  2.  3.100
  libpostproc    54.  1.100 / 54.  1.100
Input #0, mp3, from '01_Engarrafado.mp3':
  Duration: 00:05:32.96, start: 0.025057, bitrate: 160 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 160 kb/s
    Metadata:
      encoder         : LAME3.99r
    Side data:
      replaygain: track gain - -9.500000, track peak - unknown, album gain - unknown, album peak - unknown,