Decibel (WIP)

Networked audio player services.

player

A player process plays audio from URLs through the host's speakers. It maintains a queue of playable URLs and notifies connected clients whenever its state changes.

To start a player, run:

$ decibel-player

For available flags and options, run:

$ decibel-player -h

  Usage: decibel-player [options]

  Options:

    -h, --help         output usage information
    -V, --version      output the version number
    -p, --port <port>  the port on which to listen (defaut 3000)
    -d, --debug        log debugging messages

The player process is controllable via a WebSocket connection:

var socket = new WebSocket('http://localhost:3000');

// RPC call (calls `play(0, 0)` on the server)
socket.send(JSON.stringify({ name: 'play', args: [0, 0] }));

// Listen for state changes from the server
socket.onmessage = function (msg) {
    var data = JSON.parse(msg.data);
    console.log(data.name, data.args);
};

API

• append([items]) - append the given items to the player queue (each item must have a URL property)
• replace([items]) - replace the player queue with the given items
• next() - advance to beginning of next item
• prev() - advance to beginning of previous item (or current item if no previous item exists)
• pause() - stop the playback but preserve the current item index and postiion
• play(index, position) - play the item at the given index at the specified position (current index and position values will be used if left undefined)
• stop() - stop the playback and reset the current item index and position

Events

• queue:reset - the player queue was reset with the items passed in the first arg
• queue:add - the item passed in the first arg was appended to the player queue
• state - the player state changed to the values in the first arg (object includes index, status and position properties)

Discovery

Decibel uses multicast DNS-SD (i.e. Zeroconf/Bonjour) to discover services on the network. Decibel services all use the service type _decibel._tcp and include a name attribute in the TXT record corresponding to the specific type service (i.e. decibel-player).

index

TODO

fileserver

TODO