EchoAssigner

This is a python library that automatically composes an accompaniment part for a melody consisting of a single note in a piano performance. The created musical score data can be handled as a music21 object.

• Input：MIDI file of a melody consisting of a single note.
• Output：MIDI file of the melody with the accompaniment part added.
• Supported midi formats:
  • 4/4 time signature
  • BPM constant
  • major key

Installation

$ pip install echo-assigner

Usage

See tutorial.py for details.

from echo_assigner import EchoAssigner

# create EchoAssigner instance
ea = EchoAssigner(INPUT_MIDI, distmethod=0) 

# check settings params
ea.cui.show_params()

# show assigned measure
ea.cui.show_assigned_part() 

# show accuracy of simulaly of input melody and knowledge base melody
ea.cui.accuracy() 

# create m21.stream.Stream
stream = ea.create.fit_stream() 

# write midi file
stream.write("midi", OUTPUT_MIDI) 

How is this doing

1. Divide the input melody at regular intervals. (Divided intervals can be set with division parameter)

2. Extract specific features for each divided interval and express the melody as a vector. The features change depending on the model parameter.

3. Calculate the distance between the input melody and the knowledge base melody for each divided interval.

4. Assign the knowledge base melody with the smallest distance to the input melody.

Class and methods Description

class - EchoAssigner()

[need]

• input_path: path of input midi file
• distmethod: method of distance calculation
  • 0 :Euclidean
  • 1 :Chebyshev
  • 2 :Manhattan
  • 3 :Minkowski
  • 4 :Cosine

[optional]

• logs: whether to output logs at runtime (default: True)

• model: model selection

  • pitchclass: model with pitch class as feature
  • statistic: model with 5 features
    • first pitch
    • average pitch
    • variance of pitch
    • average change in pitch
    • note density as features

• division: section of extracted features

  • 0.5 :1/2 measure
  • 1 :1 measure
  • 2 :2 measure

class instance - EchoAssigner.cui

• .show_params(): show settings params
• .show_assigned_part(): show information of assigned part
  • method:
    • text: show as text in terminal
    • png: save score as png & musicxml file
    • midi: save score as midi file
  • dirpath: directly path to save score (default: None)
• .show_similar_melody(): show information of melody of high similarity
  • method:
    • text: show as text in terminal
    • png: save score as png & musicxml file
    • midi: save score as midi file
  • dirpath: directly path to save score (default: None)
• .show_melody_vector(): show melody vector of similarity of input and knowledge base
• .accuracy(): show accuracy of similarity of input melody and knowledge base melody

class instance - EchoAssigner.create

• .score(): Returns similarity numbers and knowledge base part labels
• .give_measures(): Return scale for each measure and note from part label
• .setup_part(): Construct and return stream.Part from the scale of each measure and note
• .shift_notes(): Shift stream.Part configured in setup_part to the input scale
• .fit_stream(): Configure stream.Stream