Module: BpmFinderApp

Defined in:
lib/bpm_finder_app.rb

Class Method Summary collapse

Class Method Details

.calculate_bpm_from_intervals(timestamps) ⇒ Object 



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# File 'lib/bpm_finder_app.rb', line 2

def self.calculate_bpm_from_intervals(timestamps)
  return nil if timestamps.nil? || timestamps.length < 2
  intervals = []
  (1...timestamps.length).each do |i|
    intervals << (timestamps[i] - timestamps[i - 1]).abs
  end
  avg_interval = intervals.sum / intervals.length.to_f
  return nil if avg_interval <= 0
  (60000.0 / avg_interval).round
end

.calculate_delay_times(bpm) ⇒ Object 



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# File 'lib/bpm_finder_app.rb', line 13

def self.calculate_delay_times(bpm)
  quarter = 60000.0 / bpm
  {
    quarter_note_ms: quarter.round(2),
    eighth_note_ms: (quarter / 2.0).round(2),
    sixteenth_note_ms: (quarter / 4.0).round(2),
    dotted_eighth_ms: (quarter * 0.75).round(2),
    triplet_eighth_ms: ((quarter * 2.0) / 3.0).round(2)
  }
end

.calculate_reverb_predelay(bpm) ⇒ Object 



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# File 'lib/bpm_finder_app.rb', line 24

def self.calculate_reverb_predelay(bpm)
  quarter = 60000.0 / bpm
  sixteenth = quarter / 4.0
  eighth = quarter / 2.0
  {
    tight_predelay_ms: (sixteenth / 2.0).round(2),
    natural_predelay_ms: sixteenth.round(2),
    spacious_predelay_ms: eighth.round(2)
  }
end