How to change the bit rate of audio while converting from midi file to mp3 using ffmpeg/fluidsynth

Question

I am trying to convert midi file to mp3 using fluidsynth and ffmpeg on Windows 10 OS.

fluidsynth -a alsa -T raw -F - "FluidR3Mono_GM.sf3" simple.mid |  ffmpeg -ab 192k -f s32le -i  simple.mp3

The audio bit rate specification : -ab 192k or -b:a 192k are creating an error:

You are applying an input option to an output file or viceversa.

Is there an option to specify bit rate in the above command.

score 1 · Answer 1 · answered Jun 11 '21 at 08:30

Use timidity and ffmpeg

sudo apt-get install timidity

sudo apt-get install ffmpeg

If I have the file honorthyfather.mid you can choice

For midi to mp3

timidity honorthyfather.mid -Ow -o - | ffmpeg -i - -acodec libmp3lame -ab 320k honorthyfather.mp3

For more quality use WAV

timidity honorthyfather.mid -Ow -o - | ffmpeg -i - -acodec pcm_s16le honorthyfather.wav

For quality same WAV but low size use FLAC

timidity honorthyfather.mid -Ow -o - | ffmpeg -i - -acodec flac honorthyfather.flac

Working on a Windows 10 system. Timdity is not working in my W10. — Vinod, Jun 12 '21 at 01:36

llogan · Accepted Answer · 2021-06-12T03:10:20.093

1

Option placement matters with ffmpeg. You're attempting to apply an output option to the input.

ffmpeg [input options] input [output options] output

Corrected command:

fluidsynth -T raw -F - sound_font_file.sf3 input.mid | ffmpeg -y -f s32le -i - -b:a 192k output.mp3

Fore more info about MP3 encoding with ffmpeg see FFmpeg Wiki: MP3.

edited Jun 12 '21 at 03:10

answered Jun 12 '21 at 02:41

llogan

The command really works. The volume is low. How to increase volume. – Vinod Jun 12 '21 at 02:49
@Vinod Refer to `fluidsynth --help`. See `-g`/`--gain` option. – llogan Jun 12 '21 at 03:02

2 Answers2