Transcoder

Transcode lossless music files (flac) into lossy ones (mp3/ogg).

Description

Script for transcoding lossless audio files (flac) to lossy formats like mp3 or ogg. When transcoding, tags are derived from the lossless file. Also album art is embedded in the lossy file. In the end, the lossy tree exactly resembles the lossless tree: (lossy) files which do not have a lossless source, are deleted. Script can be run in a headless environment, logging to a predefined logfolder.

Requirements

• python3

Installation

sudo apt install vorbis-tools # oggenc
sudo apt install lame
sudo apt install flac
sudo apt install python3-mutagen # alternative $ pip3 install mutagen
sudo apt install python3-pil # alternative $ pip3 install pillow

wget https://raw.githubusercontent.com/markbaaijens/transcoder/master/transcoder.py -O transcoder.py
chmod +x transcoder.py

Usage

python3 transcoder.py --help
(using python3 as a prefix is optional, ./transcoder.py also works)

Tools needed for testing

sudo apt install ffmpeg

Example(s)

python3 transcoder.py --verbose <music folder>/flac --mp3folder <music folder>/mp3 --logfolder .
show output to console, transcoding to mp3 (default to 128 kbs), log to current folder

python3 transcoder.py <music folder>/flac --mp3folder <music folder>/mp3 --mp3bitrate 256
transcoding to mp3 at bitrate 256 kbs (default = 128 kbs), no output

python3 transcoder.py --dry-run --verbose <music folder>/flac --oggfolder <music folder>/ogg --oggquality 3
test run, show output to console, transcoding to ogg at level 3 (default = 1)

python3 transcoder.py --verbose <music folder>/flac/ --mp3folder <music folder>/mp3 --oggfolder <music folder>/ogg
transcode simultaneously to mp3 and ogg

Notes

• if no value is given to mp3folder, no transcoding to mp3 will take place
• if no value is given to oggfolder, no transcoding to ogg will take place
• note that lossy folders must exist before transcoding
• when given --logfolder, operations will be logged to transcoder.log
  • watch log: tail -f transcoder.log
• for embedding album art in the transcoded files, the script expects a file cover.jpg in the lossless (flac) folder; otherwise no embedding can take place
• transcoded files won't be checked on there current compression (MP3 bitrate / OGG quality level) and will be ignored