Class: MelodyToMidi

Inherits:
Object
  • Object
show all
Defined in:
lib/melody_to_mid.rb

Overview

Converts a programmatically-defined melody to Midi.

Instance Method Summary collapse

Instance Method Details

#make_midi(melody_file, output_file) ⇒ Object

Creates a Midi file from a ruby program defining a melody. It writes its output to the path specified by output_file.

melody_file is expected to contain the following functions:

melody() - contains a melody (see process_melody for details)
mybpm() - optional, sets the BPM (or default to 60 if not specified)



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# File 'lib/melody_to_mid.rb', line 82

def make_midi(melody_file, output_file)
  seq = Sequence.new()

  require_relative 'shared_functions'
  load melody_file

  track = Track.new(seq)
  seq.tracks << track
  bpm = 60
  if defined? mybpm
    bpm = mybpm()
  end
  track.events << Tempo.new(Tempo.bpm_to_mpq(bpm))
  track.events << MetaEvent.new(META_SEQ_NAME, 'Sequence Name')

  track = Track.new(seq)
  seq.tracks << track

  track.name = 'Melody Track'
  track.instrument = GM_PATCH_NAMES[0]

  track.events << Controller.new(0, CC_VOLUME, 127)
  track.events << ProgramChange.new(0, 1, 0)

  process_melody(track, melody())

  File.open(output_file, 'wb') { |file| seq.write(file) }
end