Kast

An open source streaming stick with a few tricks up its sleeves

alternatively,

An extensible open-source daemon for displaying arbitrary media on the big screen.

Goals / Guiding Principles

• To achieve a user experience on par with the Google Chromecast
• To preserve the privacy and respect the attention of the user
• To provide an extensible platform for developing lightweight big screen experiences
  • Note: The "Chromecast Use-case" is considered the first class use-case

Guiding Principles

• Less UI is better UI

Features

• HTTP API that allows playing of any youtube-dl supported URLs
• Random pictures when idle

Design

In its current implementation, Kast acts as a mediator between multiple processes (modules) which share exclusive access to the screen. The HTTP API allows local clients to invoke functions from each module, which may decide to pre-empt the current module (the default of which being the slideshow module). Once the running module is terminated, the new module is run. When any module terminates without being pre-empted, the slideshow module is automatically loaded. In addition to the slideshow module, the media module allows any youtube-dl supported media to be streamed.

Installation

Currently based on Raspbian Lite:

• DD raspbian lite to SD card
• touch ssh in boot if desired
• Set passwords (passwd and sudo passwd)
• raspi-config
  • Set hostname
• ssh-copy-id
• sudo nano /etc/ssh/sshd_config
  • PermitRootLogin no
  • PasswordAuthentication no
• Install dependencies: apt-get update && apt-get upgrade && apt-get install vlc chromium-browser unclutter lightdm bspwm python-pip pulseaudio
• Optional: Install dev dependencies apt-get install golang git
• Install youtube-dl sudo pip install --upgrade youtube_dl
• sudo nano /etc/lightdm/lightdm.conf
  • Find or set these values:
    • autologin-user=pi
    • autologin-session=bspwm
• Clone the repo and go build / download the binary
• Copy kast to /usr/bin/ and copy the service files to /etc/systemd/user/
• Enable kast.service with the --user flag
• Reboot

You can now build and run the binary with DISPLAY=:0 XDG_RUNTIME_DIR=/run/user/1000 kast

To speed up boot:

https://www.myhelpfulguides.com/2018/10/20/how-improve-raspberry-pi-boot-time-raspbian-lite/s https://raspberrypi.stackexchange.com/questions/5256/how-can-i-improve-boot-time-on-raspbian

• Disable services:

  • avahi-daemon
  • bluetooth
  • triggerhappy

• Edit configs

  • /boot/config.txt
    • boot_delay=0