Why?¶

• Tools like jacktrip are built to work in high bandwidth academic networks like the internet2 or GEANT networks. Matriz is built to offer the lowest latencies possible, while using the least bandwidth possible. This allows musicians to have low latency high quality music streaming using regular network connections.
• For fun.

Features¶

• Low latency (using OPUS codec)
• Easy to use and extend
• Tested in live performances
• Documentation: https://matriz.readthedocs.org.

What?¶

The software is composed of two components, the client and the configuration server. The client connects to the server over websockets and receives a list of all connected clients. After starting it’s own RTSP stream with audio from the sound card, it spawns an RTSP client for all connected clients, forming a P2P streaming network. For all connection or disconnection events, the client list is broadcasted to all connected clients, which open or close new RTSP clients as necessary. Audio is encoded with the OPUS codec, which allows for low bandwidth use and high quality sound, while keeping the latency to a minimum.

The system was used several times in live peformances, with three three groups of musicians. Distances between groups ranged from tens of meters (same building) to 150 to 400 km in the final performance. The hardware used was a Raspberry pi 2 with a Focusrite Scarlet 2i2 USB sound card. The resulting streams where broadcasted live at http://stress.fm. More information, including recordings of the performances, can be obtained at the project website: http://matriz.stress.fm. For any inquiries concerning the software or the project, contact us at info@stress.fm.

Installation¶

$ echo "deb http://matriz.stress.fm/deb_repo jessie main" | sudo tee /etc/apt/sources.list.d/matriz.list
$ curl http://matriz.stress.fm/deb_repo/matriz_deb.gpg.asc | sudo apt-key add -
$ sudo apt-get update

$ sudo apt-get install -y python-pip\
                     jackd2 \
                     python-gst-1.0 \
                     python-gi \
                     libgstrtspserver-1.0-0 \
                     gstreamer1.0-plugins-bad \
                     libgstreamer-plugins-bad1.0 \
                     gir1.2-gst-rtsp-server-1.0 \
                     python-dev \
                     libffi-dev

# For the PI

$ curl https://raw.githubusercontent.com/stressfm/matriz/master/config/etc-dbus-1-system.d-matriz_jackd.conf | sudo tee /etc/dbus-1/system.d/matriz_jackd.conf >/dev/null
$ curl https://raw.githubusercontent.com/stressfm/matriz/master/config/boot-config.txt | sudo tee /boot/config.txt > /dev/null
$ curl https://raw.githubusercontent.com/stressfm/matriz/master/config/boot-cmdline.txt | sudo tee /boot/cmdline.txt >/dev/null
$ curl https://raw.githubusercontent.com/stressfm/matriz/master/config/supervisord.conf | sudo tee /etc/supervisord.conf >/dev/null
$ for cpu in /sys/devices/system/cpu/cpu[0-9]*; do echo -n performance | sudo tee $cpu/cpufreq/scaling_governor; done
$ sed -i "$(wc -l /etc/rc.local | cut -d' ' -f1)i for cpu in /sys/devices/system/cpu/cpu[0-9]*; do echo -n performance > $cpu/cpufreq/scaling_governor; done" /etc/rc.local
$ sed -i "$(wc -l /etc/rc.local | cut -d' ' -f1)i sudo mount -o remount,size=256M /dev/shm" /etc/rc.local
$ sudo pip install supervisor
$ sed -i "$(wc -l /etc/rc.local | cut -d' ' -f1)i supervisord -c /etc/supervisord.conf" /etc/rc.local
$ sudo reboot

$ pip install matriz

$ pip install matriz[server]

curl https://raw.githubusercontent.com/stressfm/matriz/master/scripts/install.sh | sudo bash -

Usage¶

$ matriz

$ matriz <filename>

{
    "key": "key1",
    "name": "porto",
    "url": "ws://localhost:5000/config",
    "interface": "eth0",
    "port": 8554,
    "client_pem": "fake_client.pem",
    "client_crt": "fake_client.crt",
    "ca_crt": "fake_ca.crt"
}

$ matriz -h

{
  "client_keys": [
        {"name": "porto", "key": "key1"},
        {"name": "montemor", "key": "key2"},
        {"name": "lisboa", "key": "key3"},
        {"name": "marte", "key": "key666"}
  ],
  "monitor_key": {"name": "monitor", "key": "monitorkey"}
}

Partners¶

• Oficinas do Convento
• Sonoscopia
• Osso
• Trienal de Arquitectura de Lisboa
• Digitópia - Casa da Música
• Câmara Municipal de Montemor-o-Novo.

Funding¶

• Direção Geral das Artes.

Types of Contributions¶

Get Started!¶

Ready to contribute? Here’s how to set up matriz for local development.

1. Fork the matriz repo on GitHub.

2. Clone your fork locally:

   $ git clone git@github.com:your_name_here/matriz.git
   

3. Install your local copy into a virtualenv. Assuming you have virtualenvwrapper installed, this is how you set up your fork for local development:

   $ mkvirtualenv matriz
   $ cd matriz/
   $ python setup.py develop
   

4. Create a branch for local development:

   $ git checkout -b name-of-your-bugfix-or-feature
   

   Now you can make your changes locally.

5. When you’re done making changes, check that your changes pass flake8 and the tests, including testing other Python versions with tox:

   $ flake8 matriz tests
   $ python setup.py test
   $ tox
   

   To get flake8 and tox, just pip install them into your virtualenv.

6. Commit your changes and push your branch to GitHub:

   $ git add .
   $ git commit -m "Your detailed description of your changes."
   $ git push origin name-of-your-bugfix-or-feature
   

7. Submit a pull request through the GitHub website.

Pull Request Guidelines¶

Before you submit a pull request, check that it meets these guidelines:

1. The pull request should include tests.
2. If the pull request adds functionality, the docs should be updated. Put your new functionality into a function with a docstring, and add the feature to the list in README.rst.
3. The pull request should work for Python 2.6, 2.7, 3.3, and 3.4, and for PyPy. Check https://travis-ci.org/stressfm/matriz/pull_requests and make sure that the tests pass for all supported Python versions.

Tips¶

To run a subset of tests:

$ python -m unittest tests.test_matriz

Core Developers¶

• Cláudio Rego <claudiojmrego@gmail.com>
• Hugo Martiniano <hugomartiniano@gmail.com>
• Vasco Pita <vasco.pitaf@gmail.com>

Contributors¶

None yet. Why not be the first?