1. Interactive, Evolutionary Textured Sound Composition Sidney Fels 1 and Jônatas Manzolli 2 (1) Dept. of Electrical and Computer Engineering University of British Columbia - Canada ssfels@ece.ubc.ca (2) Interdisciplinary Nucleus for Sound Studies (NICS) University of Campinas (UNICAMP) - Brazil jonatas@nics.unicamp.br

2. 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

3. 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

4. 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

5. 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

6. System Diagram

7. Genetic Operations Fitness Function –min D = ∑ ∑ (h 0,j - g ij ) 2 where i = 1..20, j = 1…3 and h 0,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

8. 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

9. Real time controllers GUI - graphic interface Polhemus Fastrak Local Position System (LPS)

10. Visualization of 20 melodies length = log 10 (duration +1)*6 angle = ((note1 - note2)*10 +180)/(2.0*3.14) width = (velocity/127.0)*4.0 + 1

11. Results Hidden Melody Mutated Melody

12. Textured Sounds Textured Hiden Textured Mutation

13. Textured Sounds

14. 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

15. Jônatas Manzolli jonatas@nics.unicamp.br University of Campinas - Unicamp Brazil Examples of results http://www.ece.ubc.ca/~hct/IGGM Address for Contact Sidney Fels ssfels@ece.ubc.ca University of British Columbia Canada