JellyHat

JellyHat is a Python-based "Now Playing" dashboard for the Pimoroni Display HAT Mini, specifically designed to interface with Jellyfin media servers. It provides real-time track metadata, album/artist artwork, and hardware monitoring for your Raspberry Pi.

Features

• Real-time Metadata: Displays current track title and artist from active Jellyfin sessions.
• Dynamic Artwork: Tries to use backdrop, primary cover, then logo from JellyFin, before falling back to a local placeholder for the main display.
• Hardware Monitoring: Real-time CPU temperature display with a configurable LED warning system (transitions to red if the Pi gets too hot).
• Energy Saving: Automatic screen blanking after a configurable period of inactivity.
• Robust Rendering: Support for screen rotation for flexible mounting.

Hardware Requirements

• Raspberry Pi (tested on Pi 4)
• Pimoroni Display HAT Mini

Installation

1. Clone the Repository:

   git clone https://github.com/freakylefty/jellyhat.git
   cd jellyhat

2. Install Dependencies: It is recommended to use a virtual environment.

   pip install -r requirements.txt

   Note: If you encounter issues with numpy or st7789, ensure you have system dependencies installed:

   sudo apt-get install libatlas-base-dev gfortran

3. Configure Environment: Copy the example environment file and add your Jellyfin details:

   cp .env.example .env
   nano .env

   Required variables:

   • JELLYFIN_URL: Your server address (e.g., http://192.168.1.50:8096)
   • JELLYFIN_API_KEY: Generated in Jellyfin Dashboard -> API Keys

Usage

Run the script directly:

python3 jellyhat.py

Command Line Arguments

• --interval (-i): Refresh rate in seconds (Default: 5)
• --threshold (-t): CPU Temp (°C) to trigger Red LED (Default: 70.0)
• --rotate (-r): Rotate display 180 degrees (Default: False)
• --blank (-b): Minutes of idle before screen blanking (Default: 10)
• --hide-temp (-H): Hide the CPU temperature text (Default: False)
• --debug (-d): Enable verbose console logging (Default: False)

Customization

JellyHat uses a centralized THEME dictionary at the top of the script. This allows you to easily modify the look and feel of the interface—including colors, font sizes, and UI element positions—without needing to rewrite the core logic.

Example: Changing the Background Color

To change the background from black to a dark navy blue, locate the colors section in the THEME object and update the RGB values:

"colors": {
    "background": (0, 0, 20),  # Modified for a dark navy look
    "text_main": (255, 255, 255),
    ...
}

Key Theme Settings

• fonts: Set the path to your .ttf file and adjust sizes for titles and status text.
• colors: Define RGB tuples for text, backgrounds, and temperature-based LED warnings.
• layout: Adjust X/Y coordinates to shift text or change the maximum dimensions for artwork.

Running As a Service

Create the service file

sudo nano /etc/systemd/system/jellyhat.service

Paste the configuration (make sure to update the paths and your_username):

[Unit]
Description=JellyHat Display Service
After=network.target

[Service]
# Replace with your actual user, path and options
# e.g. ExecStart=/usr/bin/python3 /home/pi/jellyhat/jellyhat.py -r
User=<username>
WorkingDirectory=<path_to_project>
ExecStart=/usr/bin/python3 <path_to_project>/jellyhat.py

# Auto-restart logic
Restart=always
RestartSec=5

# Ensure output goes to system logs
StandardOutput=inherit
StandardError=inherit

[Install]
WantedBy=multi-user.target

Start and enable the service:

# Reload systemd to recognize the new file
sudo systemctl daemon-reload

# Enable it to run at boot
sudo systemctl enable jellyhat.service

# Start it now
sudo systemctl start jellyhat.service

Management:

Task	Command
Check Status	sudo systemctl status jellyhat.service
Stop Service	sudo systemctl stop jellyhat.service
Restart Service	sudo systemctl restart jellyhat.service
View Live Logs	journalctl -u jellyhat.service -f

Project Structure

• jellyhat.py: The main application logic.
• requirements.txt: Pinned library versions for stability.
• fonts/: Directory for UI fonts (e.g., Roboto).
• placeholder.jpg: Fallback image when no artwork is available.
• .env: (User Created) Secure storage for API credentials.

License

This project is licensed under the MIT License.