1. Standalone Voctomix Machine

The simplest setup that is able to record a talk is a camera connected to a PC running Voctomix. This can be done as follows:

  1. Install Debian Stable on a machine. Make the hostname voctomix1. We recommend a minimal install: only the base system and optionally, an SSH server. The netinstall image is good for this.

  2. Once it is installed, run the following as root:

    $ echo "deb http://deb.debian.org/debian stretch-backports main" > /etc/apt/sources.list.d/stretch-backports.list
    $ apt update
    $ apt install git
    $ apt -t stretch-backports install ansible
    $ git clone https://salsa.debian.org/debconf-video-team/ansible
    $ cd ansible
    
  3. Edit inventory/group_vars/all and change the following:

    public_keys_onsite: [
      <Place your ED25519 SSH public key here>
    ]
    
    public_keys_root: [
      <Place your ED25519 SSH public key here>
    ]
    
  4. Run:

    $ ansible-playbook --inventory inventory/hosts --connection local -l voctomix1 site.yml
    
  5. When it completes successfully, restart the machine.

You should now have a working voctomix machine. Since there is only one input at the moment, you cannot really mix different streams. The next step is to build an opsis machine to get a second input. To do this, you might need to build a gateway machine first.

1.1. Streaming

Streaming to services such as YouTube is very easy using this setup. It requires setting up the stream on YouTube and then configuring Voctomix to connect to this stream.

  1. Open YouTube Live Dashboard.

  2. Change the Name and Description, setting the Category and Privacy as required.

  3. Note down the Server URL and Stream name/key (which will be displayed as a hidden password until the Reveal button is pressed). These will be used to configure Voctomix using Ansible.

  4. Create an Ansible Vault file for the vault password:

    $ echo "changeme" > /root/.ansible-vault
    $ chmod 600 /root/.ansible-vault
    
  5. Encrypt the URL and stream name in the form <URL>/<Stream name>:

    $ ansible-vault encrypt_string --vault-password-file=/root/.ansible-vault --name=location <URL>/<Stream name>
    
  6. Edit inventory/host_vars/voctomix1.yml and include the following, changing the bitrates as required:

    streaming:
      method: rtmp
      hq_config:
        video_bitrate: 2000 # kbps
        audio_bitrate: 128000 # bps
        keyframe_period: 60 # seconds
      rtmp:
        vaapi: true
        <Output of ansible-vault encrypt_string>
    
  7. Rerun ansible:

    $ ansible-playbook --vault-password-file=/root/.ansible-vault --inventory inventory/hosts --connection local -l voctomix1 site.yml
    

Once ansible is finished, opening Voctomix and selecting Stream Live or Stream Loop will start streaming to YouTube. If you wish to run more than one room or schedule when your stream goes live, use the Event tab and schedule the stream. Here you can add cameras for additional rooms (one per room).

1.2. Notes

Ansible can be run from a laptop or other external source. This makes testing changes much faster than running it locally. You will require a network that resolves hostnames to IP addresses correctly. It also requires your SSH key to be present in the authorized_keys file for root (this will be the case if your key is in the public_keys_root list and you have run ansible before). In this case run:

$ ansible-playbook --inventory inventory/hosts -l voctomix1 site.yml

In inventory/group_vars/all there are two sets of settings which may be of interest: Blackmagic drivers and Voctomix loops. The Blackmagic drivers are the proprietary drivers for the HDMI/SDI PCI capture cards that we use. If you are also using them, uncomment the following and change the URLs to point to the corresponding package files.

blackmagic:
  urls:
    desktopvideo: http://example.org/desktopvideo_10.9.5a4_amd64.deb
    desktopvideo_gui: http://example.org/desktopvideo-gui_10.9.5a4_amd64.deb
    mediaexpress: http://example.org/mediaexpress_3.5.3a1_amd64.deb
  dkms_version: 10.9.5a4

The Voctomix loops are shown on the stream when there is no talk happening. In Voctomix the loop_url is downloaded and used for the Stream Loop button when the stream is blanked. bgloop_url is downloaded and used as the background for Picture-In-Picture mode when the sources do not cover the entire frame. If you have loops to use, put the URL for them here:

voctomix:
  loop_url: http://example.org/loop/loop.ts
  bgloop_url: http://example.org/loop/bgloop.ts