A Genetic Musician

Thematic Music Generation with Genetic Algorithms

Outline

Introduction Song Structure First Genetic Algorithm : The Root Melody Second Genetic Algorithm : The Harmonizing

Voices Results and Conclusion Questions

Introduction

Very Little Practical Value?– Human Curiosity

Implementation employs two separate GAs to create songs with Variations of common themes

User sets parameters via parameter files– GA parameters for both genetic algorithms– Song structure

Song Structure

A CB A B B A B C C

Root A

Harm A

Root Melody: Genomes

Two separate sets of Genomes– The notes

12 Semitones – A, A#/Bb, B, C, C#/Db, D, D#/Eb, E, F, F#/Gb, G, G#/Ab

Rest Hold

– The Octaves 4 octave range 1 null octave (rest, hold)

Size of individual is dependent upon notelength and time signature

– 8 eighth-notes per measure = 16 total genomes

Root Melody: Note Shorten and Note Extend Operators

Note Shorten– Shortens

the length of a note or rest

Note Extend– Extends the

length of a note or rest

Shorten Operator

O D rst C hd 1 0 2 0

N D rst C B 1 0 2 1

Extend Operator

O A# hd C F# 1 0 2 3

N A# hd hd F# 1 0 0 3

Root Melody: Note Change and Octave Change

Note Change– Changes a note

or rest

Octave Change– Changes the

octave of a note

Note Change Operator

O D rst C G 1 0 2 1

N D rst C B 1 0 2 1

Octave Change Operator

O A# hd C F# 1 0 2 3

N A# hd C F# 1 0 3 3

Root Melody: Fitness Function

Multi-Objective Fitness Function– Key– Octave– Note Percentage

Transition

Once the measures are sufficiently-evolved, a string of measures from the same population is used to create the root melody

This root melody is used for every movement of the same theme

Harmonizing Voices: Genomes and Operators

Genomes and Operators same as in First Genetic Algorithm

Individuals hold information for full movement, instead of just single measures

Harmonizing Voices: Fitness Function

Consonance Matrix Chords

– Minor chords– Major chords

Octave Key Note Percentage

Results

Results Chaotic with Moments of Clarity Parameters are hard to analyze Midi 1 Midi 2 Midi 3 Midi 4 Midi 5 Midi 6

fin

Questions?