Class: Wavesync::EssentiaBpmDetector

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

Constant Summary collapse

PYTHON_SCRIPT = 
<<~PYTHON
  import essentia, essentia.streaming as ess, json, sys
  pool = essentia.Pool()
  loader = ess.MonoLoader(filename=sys.argv[1], sampleRate=44100)
  rhythm = ess.RhythmDescriptors()
  loader.audio >> rhythm.signal
  rhythm.bpm >> (pool, 'bpm')
  rhythm.confidence >> (pool, 'confidence')
  essentia.run(loader)
  print(json.dumps({'bpm': round(float(pool['bpm'])), 'confidence': round(float(pool['confidence']), 2)}))
PYTHON

Class Method Summary collapse

Class Method Details

.available? ⇒ Boolean

: () -> bool?

Returns:

  • (Boolean) 


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# File 'lib/wavesync/essentia_bpm_detector.rb', line 22

def self.available?
  PythonVenv.essentia_available?
end

.detect(file_path) ⇒ Object

: (String file_path) -> Integer, confidence: Float?



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# File 'lib/wavesync/essentia_bpm_detector.rb', line 27

def self.detect(file_path)
  output = PythonVenv.run_script(PYTHON_SCRIPT, file_path)
  data = JSON.parse(output.strip)
  bpm = data['bpm'].to_f
  bpm.positive? ? { bpm: bpm.round, confidence: data['confidence'].to_f } : nil
rescue StandardError
  nil
end