Audio Format Conversion

WavPack -> flac

Use ffmpeg to convert WavPack to flac:

ffmpeg -i audiofile.wv audiofile.flac

Cut a flac into tracks on cue

From CUE_Splitting.

1. Install cuetools and shntool, man shntool:

   sudo apt install cuetools shntool
   

2. To split flac:

   shnsplit -f file.cue -t %n-%t -o flac file.flac
   

flac -> m4a lossless

Convert all flac files in the directory to alac m4a - vegetable is good for you.

for fn in *.flac; \
    do ffmpeg -i $fn -c:v copy -c:a alac "`basename $fn .flac`.m4a"; done

Merge MP3 Files

1. Install mp3wrap:

   sudo apt install mp3wrap
   

2. Verify the wildcard:

   > ls -la 0000[2-7].mp3
   -rw-rw-r-- 1 alex alex 6010297 Mar 31 10:39 00002.mp3
   -rw-rw-r-- 1 alex alex 6300734 Mar 31 10:39 00003.mp3
   -rw-rw-r-- 1 alex alex 6065677 Mar 31 10:39 00004.mp3
   -rw-rw-r-- 1 alex alex 6829497 Mar 31 10:39 00005.mp3
   -rw-rw-r-- 1 alex alex 6829453 Mar 31 10:39 00006.mp3
   -rw-rw-r-- 1 alex alex 5850383 Mar 31 10:39 00007.mp3
   

3. Use the wildcard from the first step to pass the files to mp3wrap: ```

   mp3wrap chapter01.mp3 0000[2-7].mp3 Mp3Wrap Version 0.5 (2003/Jan/16). See README and COPYING for more! Written and copyrights by Matteo Trotta - matteo.trotta@lib.unimib.it THIS SOFTWARE COMES WITH ABSOLUTELY NO WARRANTY! USE AT YOUR OWN RISK!

16 % –> Wrapping 00002.mp3 … OK 33 % –> Wrapping 00003.mp3 … OK 50 % –> Wrapping 00004.mp3 … OK 66 % –> Wrapping 00005.mp3 … OK 83 % –> Wrapping 00006.mp3 … OK 100 % –> Wrapping 00007.mp3 … OK

Calculating CRC, please wait… OK

chapter01_MP3WRAP.mp3 has been created successfully! Use mp3splt to dewrap file; download at http://mp3splt.sourceforge.net!

## Merge MP3 Files using `ffmpeg`

Use [ffmpeg concat demuxer](https://trac.ffmpeg.org/wiki/Concatenate#demuxer).

Create `files.txt` using e.g.:
```sh
for f in *.mp3; do echo "file '$f'" >> files.txt; done

files.txt:

# this is a comment
file 'path/to/chapter1.mp3'
file 'path/to/chapter2.mp3'
file 'path/to/chapter3.mp3'

Concatenate the files:

ffmpeg -f concat -safe 0 -i files.txt -c copy -vn output.mp3

mp3 -> m4b

1. Prepare metadata.txt:

   ;METADATA1
   title=Book Name
   artist=Book Author
   composer=Book Narrator
   publisher=Book Publisher
   date=Book Date of Publication
   [CHAPTER]
   TIMEBASE=1/1000
   START=0 # 0:00:00
   END=60000 # 0:01:00
   title=Intro
   

Repeat the [CHAPTER] block for each chapter, specifying the START and END times in milliseconds.

1. Convert MP3 into M4B:

   ffmpeg -i "some.mp3" -i metadata.txt -map_metadata 1 -codec copy -f mp4 some.m4b
   

Add Cover Art to m4b

1. Create a cover image (optional): If you want to include cover art, save it as cover.jpg in the same directory as your MP3s.
2. Add cover art using a tool like Kid3 or other tag editors.