Transcript A Genetic Musician

A Genetic Musician
Thematic Music
Generation with
Genetic Algorithms
Outline
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Introduction
Song Structure
First Genetic Algorithm : The Root Melody
Second Genetic Algorithm : The Harmonizing
Voices
Results and Conclusion
Questions
Introduction
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Very Little Practical Value?
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Human Curiosity
Implementation employs two separate GAs to
create songs with Variations of common
themes
User sets parameters via parameter files
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GA parameters for both genetic algorithms
Song structure
Song Structure
A
B
A
B
C
B
A
B
Root A
Harm A
C
C
Root Melody: Genomes
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Two separate sets of Genomes
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The notes
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12 Semitones
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Rest
Hold
The Octaves
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A, A#/Bb, B, C, C#/Db, D, D#/Eb, E, F, F#/Gb, G, G#/Ab
4 octave range
1 null octave (rest, hold)
Size of individual is dependent upon notelength and
time signature
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8 eighth-notes per measure = 16 total genomes
Root Melody: Note Shorten and
Note Extend Operators
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Note Shorten
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Shortens
the length of
a note or
rest
Note Extend
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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
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Note Change Operator
O
D
rst C
N
D
rst C
G
1
0
2
1
B
1
0
2
1
Note Change
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Octave Change
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Octave Change Operator
O
A# hd C
F# 1
0
2
3
N
A# hd C
F# 1
0
3
3
Changes a note
or rest
Changes the
octave of a note
Root Melody: Fitness Function
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Multi-Objective Fitness Function
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Key
Octave
Note Percentage
Transition
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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
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Genomes and Operators same as in First
Genetic Algorithm
Individuals hold information for full movement,
instead of just single measures
Harmonizing Voices: Fitness
Function
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Consonance Matrix
Chords
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Minor chords
Major chords
Octave
Key
Note Percentage
Results
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Results Chaotic with Moments of Clarity
Parameters are hard to analyze
Midi 1
Midi 2
Midi 3
Midi 4
Midi 5
Midi 6
fin
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Questions?