Spectra-Qualified Uncomplicated Inky Rendering Tools

A set of four one-shot Python 3 scripts for Raspberry Pi (or any Linux SBC)
that fetch or cycle images and display them on an Inky e-paper panel
(13.3″ Spectra-6 Impression, 7-colour Impression 7.3″, PHAT, WHAT, or any board detected by inky.auto).
When no hardware is present, each script falls back to headless mode and writes a *_preview.png.

• One-shot design
  Run once, display one image, exit cleanly (ideal for cron or systemd).
• Auto-install
  Installs inky & numpy under your Python interpreter if missing.
• Headless fallback
  Generates a *_preview.png when no Inky hardware is found.
• Consistent helpers
  Shared functions for HTTP, image-fitting, Inky detection, and CLI parsing.

1. Install apt dependencies

   sudo apt update && sudo apt install -y \
     git \
     python3-pip python3-setuptools python3-wheel python3-venv \
     python3-numpy python3-pil python3-spidev \
     python3-rpi.gpio python3-libgpiod \
     python3-smbus2 python3-lxml

2. Install Inky Libraries
   Follow the official Pimoroni Inky instructions.

3. Enable I2C and SPI

   sudo raspi-config nonint do_i2c 0 do_spi 0

4. Clone this repo and make scripts executable

   git clone https://github.com/fitoori/squirt.git
   cd squirt
   sudo chmod +x xkcd.py nasa.py landscapes.py save.py status.py

5. Enable the virtual environment created by Pimoroni’s inky script

   source ~/.virtualenvs/pimoroni/bin/activate

6. Install pip dependencies (if anything was missed)

   pip3 install inky numpy requests beautifulsoup4 pillow

7. (Optional) Edit Crontab

   crontab -e

   Scroll down to the bottom, paste in the following:

   0 * * * * python3 /home/$USER/squirt/xkcd.py
   @reboot sleep 10 && python3 /home/$USER/squirt/status.py && sleep 30 && python3 /home/$USER/squirt/nasa.py --apod &

   The first line will refresh the display once per hour to a display a new xkcd comic. The second line runs status.py message on boot, leaves it for ~30 seconds, then switches to showing NASA's Astronomy Photo of the Day (apod).

• Display a random XKCD comic:

  python3 ./xkcd.py

• Display a NASA image:

  python3 ./nasa.py [--apod|--mars [ROVER]|--epic|--earth LAT LON [--dim]|--search "QUERY"] [--key API_KEY]

• Fetch an unseen landscape painting from The Met or AIC:

  python3 ./landscapes.py [--met|--aic] [--wide|--tall] [--reset]

• Download & show an image from a URL, or cycle through saved images:

  python3 ./save.py [URL] [--folder DIR] [--reset]

• Tested with Inky v2.1 (pip install inky>=2.1.0)
• Supports:
  • InkyEL133UF1 (13.3″ Spectra-6 Impression)
  • InkyImpression73 (7-colour 7.3″ Impression)
  • InkyPHAT, InkyWHAT
  • Any board auto-detected by inky.auto()
• If your board lacks EEPROM, set INKY_TYPE (e.g. el133uf1, phat, what) near the top of each script.

MIT © 2025 github.com/fitoori
Contributions welcome!