Download FelsManzolliEGMM - UBC ECE - University of British Columbia

Interactive, Evolutionary Textured
Sound Composition
Sidney Fels1 and Jônatas Manzolli 2
(1) Dept. of Electrical and Computer Engineering
University of British Columbia - Canada
[email protected]
(2) Interdisciplinary Nucleus for Sound Studies (NICS)
University of Campinas (UNICAMP) - Brazil
[email protected]
Summary
• Starting Points
– Evolutionary music composition
– Interactive control of composition
• Melody Population
• System Description
– Biological and Musical Cycles
• Interaction and Visual Representation
• Results
– Musical Examples
– Piano roll representation
Starting Points
• What is musical texture?
– relationship with visual domain
– superimposition of lines or voice
• Idea from Guido d’Arezzo (XI century)
– Unknown melody played on the monocord
• Evolutionary Computation
– Fitness Function
– Mutation and Crossover
• Significant human interaction
• Constrained amount of stochasticity
Melody Population
• Note Genetic Structure
– Taken advantage of the MIDI protocol
• MIDI note number
• MIDI Velocity number
• Duration of the note
• Hiden Melody - established a priori
• Population -
20 melodies with 12 notes each one
System Description
• Three processes run concurrently
– Musical Cycle (MC)
– Genetic Cycle (GC)
– Visualization
• MC select the melody to play
– Fitness Function is applied
• The Best melody is close to the Hiden Melody
• GC applies Mutation and Crossover
– Mutation - random variations in pitch and duration
– Crossover - notes from father and mother melodies
System Diagram
Genetic Operations
• Fitness Function
– min D = ∑ ∑ (h0,j - gij)2
where i = 1..20, j = 1…3 and h0,j = Hidden Melody
• Mutation
– Mutation probability
– Change note number inside 02 octaves
– Change duration to 2(± 1)
• Crossover
– Crossover probability
– If a note is selected >>> replace it with a note from parents
Mutation example
Interaction and Visualization
• Map performer interaction semantics to evolutionary
semantics
– Increases intimacy with the system
• Relationship between 02 objetos
– Distance >>> mutation probability
– Angular deviation >>> crossover probability
• Two objetos are two people
distance
angle
Real time controllers
• GUI - graphic interface
• Polhemus Fastrak
• Local Position System (LPS)
Visualization of 20 melodies
length = log10(duration +1)*6
angle = ((note1 - note2)*10 +180)/(2.0*3.14)
width = (velocity/127.0)*4.0 + 1
Results
• Hidden Melody
• Mutated Melody
Textured Sounds
• Textured Hiden
• Textured Mutation
Textured Sounds
Future Work
• to experiment with Alternative Visualization
• to allow additional control of MIDI
• to input the Hiden Melody using MIDI controller or
a keyboard
• to further experiment with mapping of two and
three object relationship semantics
• to increase the complexity of the melody and
improve the ryhthm representation
• to evaluate the various mappings between the
interaction space
Address for Contact
Sidney Fels
[email protected]
University of British Columbia
Canada
Jônatas Manzolli
[email protected]
University of Campinas - Unicamp
Brazil
Examples of results
http://www.ece.ubc.ca/~hct/IGGM