MIDI Message
MIDI messages, objectified in Ruby
Features
-
Flexible API to accommodate various sources and destinations of MIDI data
-
Simple OO approach to System Exclusive data and devices
Install
gem install midi-
Usage
require 'midi-message'
include MIDIMessage
Basic Messages
There are a few ways to create a new MIDI message. Here are some examples
NoteOn.new(0, 64, 64)
NoteOn["E4"].new(0, 100)
with(:channel => 0, :velocity => 100) { note_on("E4") }
Those expressions all evaluate to the same object
#<MIDIMessage::NoteOn:0x9c1c240
@channel=0,
@data=[64, 64],
@name="E4",
@note=64,
@status=[9, 0],
@velocity=64,
@verbose_name="Note On: E4">
SysEx Messages
As with any kind of message, you can begin with raw data
SystemExclusive.new(0xF0, 0x41, 0x10, 0x42, 0x12, 0x40, 0x00, 0x7F, 0x00, 0x41, 0xF7)
Or in a more object oriented way
synth = SystemExclusive::Node.new(0x41, :model_id => 0x42, :device_id => 0x10)
SystemExclusive::Command.new([0x40, 0x7F, 0x00], 0x00, :node => synth)
A Node represents a device that you’re sending a message to (eg. your Yamaha DX7 is a Node). Sysex messages can either be a Command or Request
You can use the Node to instantiate a message
synth.command([0x40, 0x7F, 0x00], 0x00)
One way or another, you will wind up with a pair of objects like this
#<MIDIMessage::SystemExclusive::Command:0x9c1e57c
@address=[64, 0, 127],
@checksum=[65],
@data=[0],
@node=
#<MIDIMessage::SystemExclusive::Node:0x9c1e5a4
@device_id=16,
@manufacturer_id=65,
@model_id=66>>
Parsing
The parse method will take any valid message data and return the object representation
MIDIMessage.parse(0x90, 0x40, 0x40)
#<MIDIMessage::NoteOn:0x9c1c240 ..>
MIDIMessage.parse(0xF0, 0x41, 0x10, 0x42, 0x12, 0x40, 0x00, 0x7F, 0x00, 0x41, 0xF7)
#<MIDIMessage::SystemExclusive::Command:0x9c1e57c ..>
Check out nibbler for more advanced parsing
API Documentation
Author
-
Ari Russo <ari.russo at gmail.com>
License
Apache 2.0, See the file LICENSE
Copyright © 2011 Ari Russo