This script was made so I could batch process a collection of music files. Audacity doesn't have a multiband compressor, so I used the best audio/video encoding tool on the open-source planet: FFmpeg!

You can use this tool to process most popular audio file formats. Multiple processing options are available, meaning you can have a bit of compression or lots of it.

FFmpeg-Multiband.sh is the standard version of the script. FFmpeg-Multiband-FM.sh contains a low-pass filter suitable for FM Radio transmitting.

FFmpeg - Needed for compression and processing.

Sox - Needed for file normalization.

libsox-fmt-all - Needed by SoX for support of various audio formats

These can be installed on Debian systems by running apt install ffmpeg sox libsox-fmt-all.

Drop the bash script in a folder with music. All files you want to process have to be in the same folder as the script.

If need be, run chmod +x FFmpeg-Multiband to mark the file as executable.

Run ./FFmpeg-Multiband.sh. You will be presented with several options. Here's an example:

= = = INPUT FILE EXTENSION = = =
What is the extension of the files you are converting?
ex. (mp3) or (flac)
mp3

= = = OUTPUT FILE FORMAT = = =
What format are you exporting to?
Example: mp3, ogg, flac
mp3

= = = OUTPUT FILE BITRATE = = =
What bitrate would you like to export to?
Values in kbps, ex. (128) for 128kbps
320

= = = POST-PROCESSING = = =
Post-process files? This may be helpful if you want extra amplification.
Enter [light], [heavy], [overdrive], or press enter for none. light is recommended.
overdrive

= = = SILENCE TRIMMING = = =
Trim silence from the beginning and end of files?
Enter (yes) to trim, or press enter for no trimming.
yes

= = = FILE NAME ADDITIONS = = =
Would you like to add anything to the end of the file name?
If so, enter it here. If not, press enter.
-overdrive

The script will make two folders, one named Processing and another named Processed. The Processing folder is used as temporary storage. When the script is done, all of the results will be in Processed.

• Make FFmpeg output silent while showing encode progress
• Use FFmpeg for normalization

• Move finished files to separate folder
• Delete temporary folder instead of files
• Add low-mid band to improve lower mids