PAPA - PipeWire Async Polyphonic Audio Player

A powerful daemon for playing multiple audio tracks simultaneously through different audio channels with independent control.

Overview

PAPA (PipeWire Async Polyphonic Audio Player) is designed for scenarios where you need precise control over multiple audio sources. It's ideal for:

• Museum installations
• Interactive exhibits
• Multi-zone audio playback
• Spatial audio experiences
• Any application requiring multiple synchronized or independent audio streams

Features

• Play multiple audio tracks simultaneously with independent control
• Map audio channels to specific outputs
• Control playback through simple socket commands
• Independent volume control for each track
• Loop mode for continuous playback
• Simple command-line interface

Installation

Dependencies

• PipeWire (for audio playback)
• libyaml (for configuration parsing)
• libsndfile (for audio file loading)

Building

make

Installing

sudo make install

Usage

Starting the Server

papad

This will start the audio player daemon. The server listens for commands on a Unix socket at /var/run/papad.sock.

Client Commands

The client utility can be used to control the running server:

papa --play track1        # Play a specific track
papa --stop track1        # Stop a specific track
papa --stop-all           # Stop all playing tracks
papa --list               # List all available tracks
papa --status             # Show current playback status
papa --reload             # Reload configuration

Configuration

The configuration file is in YAML format and is searched for in the following locations:

• ./config/default.yml
• ./default.yml
• /etc/papa/config.yml

Example Configuration

logging:
  level: INFO

tracks:
  - id: track1
    file_path: /path/to/track1.wav
    loop: true
    volume: 0.8
    output:
      device: default
      mapping:
        - FL
        - FR

  - id: track2
    file_path: /path/to/track2.wav
    loop: false
    volume: 1.0
    output:
      device: default
      mapping:
        - AUX0
        - AUX1

Socket Protocol

You can control PAPA programmatically by sending commands to the Unix socket:

• play <track_id> - Play a track
• stop <track_id> - Stop a track
• stop-all - Stop all tracks
• list - List available tracks
• status - Get player status
• reload - Reload configuration

License

Apache-2.0 license