demix 1.1.0

Separate audio into stems (vocals, instruments) using AI-powered Spleeter

demix

separates audio from songs into stems (vocals, instruments), transpose music, change tempo, operates on music from youtube video or local file

prerequisites

[!NOTE] Please note: I'm using homebrew for installing virtualenvwrapper and ffmpeg. If you're using another package manager or different operating system than macOS (e.g. Linux), you need to install it differently. In the setup below I also defined separate virtualenvs for user installation demix-cli and for development demix. It's important to keep them separated if you want to use the app in two modes. If you want to use one mode only, it doesn't really matter as well as the name of the virtualenv. In the examples for creating virtualenv below, replace python path below with your own python3.8 path. I'm personally using pyenv for installing various python verions, but you can do it as you wish.

installation

I suggest to create virtualenv for this project to not break existing system-wide installations:

brew install virtualenvwrapper
brew install ffmpeg
mkdir demix-cli
cd demix-cli
mkvirtualenv -p /Users/pw/.pyenv/versions/3.8.16/bin/python demix-cli
workon demix-cli
pip install demix
demix -v

update

pip install demix --upgrade

development

prepare environment:

brew install virtualenvwrapper
brew install ffmpeg
git clone [e-mail]:pwittchen/demix.git
cd demix
mkvirtualenv -p /Users/pw/.pyenv/versions/3.8.16/bin/python demix
workon demix
pip install -r requirements.txt
python demix.py -v

virtualenv

exit virtualenv, when you're done:

deactivate

to activate env again:

for user installation:

workon demix-cli

for dev setup:

workon demix

[!TIP] You can change local names of these envs if you want to.

testing

install pytest:

pip install pytest

run all tests (-v param for verbose):

pytest -v

versioning

bump version in pyproject.toml and src/demix/__init__.py:

python bump_version.py 1.0.4

use --dry-run to preview changes without applying them:

python bump_version.py 1.0.4 --dry-run

after setting the version, create git tag with appropriate name, .e.g. v1.0.4 and push it to the repo

usage

demix -u <youtube-url> [options]
demix -s <search-query> [options]
demix -f <audio-file> [options]

options

Option	Description
-u, --url	YouTube video URL to process
-s, --search	Search YouTube for a song (e.g., 'Artist - Song Name')
-f, --file	Local audio file to process (mp3, wav, flac, etc.)
-o, --output	Output directory (default: output)
-t, --tempo	Tempo factor for output audio (default: 1.0, use < 1.0 to slow down)
-p, --transpose	Transpose pitch by semitones (default: 0, range: -12 to +12)
-ss, --start	Start time for cutting (format: MM:SS or HH:MM:SS)
-to, --end	End time for cutting (format: MM:SS or HH:MM:SS)
-m, --mode	Separation mode: 2stems, 4stems, or 5stems (default: 2stems)
-c, --clean	Clean up files: output, models, or all
-v, --version	Show version number
-h, --help	Show help message

separation modes

Mode	Stems
2stems	vocals, accompaniment
4stems	vocals, drums, bass, other
5stems	vocals, drums, bass, piano, other

examples

# separate a YouTube video into vocals and accompaniment
demix -u 'https://www.youtube.com/watch?v=VIDEO_ID'

# search YouTube by artist and song name
demix -s 'Queen - Bohemian Rhapsody' -m 4stems

# separate a local file with 4 stems
demix -f /path/to/song.mp3 -m 4stems

# cut audio from 1:30 to 3:45 before separation
demix -f song.mp3 -ss 1:30 -to 3:45

# start from 0:30 (skip intro)
demix -f song.mp3 -ss 0:30

# keep only the first 2 minutes
demix -f song.mp3 -to 2:00

# combine cutting with tempo and transpose
demix -f song.mp3 -ss 1:00 -to 4:00 -t 0.8 -p -2