Class: MTK::IO::UniMIDIInput

Inherits:
MIDIInput show all
Defined in:
lib/mtk/io/unimidi_input.rb

Overview

Note:

This class is optional and only available if you require ‘mtk/midi/unimidi_input’. It depends on the ‘unimidi’ gem.

Provides realtime MIDI input for MRI/YARV Ruby via the unimidi gem.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from MIDIInput

available_input_types, find_by_name, input_types_by_device, #name, open

Constructor Details

#initialize(input_device, options = {}) ⇒ UniMIDIInput

Returns a new instance of UniMIDIInput.



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# File 'lib/mtk/io/unimidi_input.rb', line 25

def initialize(input_device, options={})
  super
  @open_time = Time.now.to_f
end

Instance Attribute Details

#device ⇒ Object (readonly)

Returns the value of attribute device.



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# File 'lib/mtk/io/unimidi_input.rb', line 23

def device
  @device
end

#recording ⇒ Object (readonly)

Returns the value of attribute recording.



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# File 'lib/mtk/io/unimidi_input.rb', line 23

def recording
  @recording
end

#thread ⇒ Object (readonly)

Returns the value of attribute thread.



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# File 'lib/mtk/io/unimidi_input.rb', line 23

def thread
  @thread
end

Class Method Details

.devices ⇒ Object 



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# File 'lib/mtk/io/unimidi_input.rb', line 14

def self.devices
  @devices ||= ::UniMIDI::Input.all.reject{|d| d.name.strip.empty? }
end

.devices_by_name ⇒ Object 



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# File 'lib/mtk/io/unimidi_input.rb', line 18

def self.devices_by_name
  @devices_by_name ||= devices.each_with_object( Hash.new ){|device,hash| hash[device.name] = device }
end

Instance Method Details

#record(options = {}) ⇒ Object 



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# File 'lib/mtk/io/unimidi_input.rb', line 30

def record(options={})
  @recording = [] unless options[:append] and @recording
  monitor = options[:monitor]

  stop
  @thread = Thread.new do
    @start_time = Time.now.to_f
    loop do
      @device.gets.each do |data|
        puts data if monitor
        record_raw_data data
      end
      sleep 0.001
    end
  end

  time_limit = options[:time_limit]
  if time_limit
    puts "Blocking current thread for #{time_limit} seconds to record MIDI input."
    @thread.join(time_limit)
  end
end

#stop ⇒ Object 



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# File 'lib/mtk/io/unimidi_input.rb', line 53

def stop
  Thread.kill @thread if @thread
end

#to_timeline(options = {}) ⇒ Object 



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# File 'lib/mtk/io/unimidi_input.rb', line 57

def to_timeline(options={})
  return nil if not @recording

  bpm = options.fetch :bmp, 120
  beats_per_second = bpm.to_f/60
  timeline = MTK::Events::Timeline.new
  note_ons = {}
  start = nil

  @recording.each do |message, time|
    start ||= time
    time -= start
    time /= beats_per_second

    if message.is_a? MTK::Events::Event
      timeline.add time,message unless message.type == :unknown
    else
      message_type = message.type
      message_type = :note_off if message_type == :note_on and message.velocity == 0
      # TODO: this will need to be made more robust when we support off velocities

      case message_type
      when :note_on
        pitch = message.pitch
        note_ons[pitch] = [message,time]

      when :note_off
        pitch = message.pitch
        if note_ons.has_key? pitch
          note_on, start_time = note_ons.delete(pitch)
          duration = time - start_time
          note = MTK::Events::Note.from_midi pitch, note_on.velocity, duration
          timeline.add time,note
        end
      end
    end
  end

  timeline.quantize! options[:quantize] if options.key? :quantize
  timeline.shift_to! options[:shift_to] if options.key? :shift_to

  timeline
end