A molecular collision model of musical interaction

In this article, we study the creation and perception of pictures and melodies as the result of the interaction of distributed agents. In some complex systems, one can see the elaboration of global patterns by the interaction of distributed local entities. Following first abstract painters such as Kandinsky or Klee, and Gestalt theories of perception, one may also consider that pictures are composed and perceived as the result of the interaction of sets of colored graphical elements. In a similar way, one may consider that music is the result of the adequate composition of distinct sounds and that it is perceived as the interaction of sets of musical elements. In this article, we develop the idea somewhat further and show how we can take advantage of it to create computer-generated artworks. Computer-art projects such as The Garden of Chances and Mutations have been designed using these principles, and rely on a versatile multiagent platform dedicated to the real-time visualization of complex data streams.

Artificial Life, 8(1):83-86, 2002

1995

Current approaches to musical research place a strong emphasis either on sound production -synthesis, algorithmic composition -or on cognitive models -information processing. As a way to start ploughing a common ground we outline a framework where musical structure is determined by the interaction of three interdependent aspects: sound system (physical), perceptual system (psychological) and social system. These are interlinked dynamically and their interaction provides a transformation of the state of each system. Information is defined by the range and rate of transformation of the elements in the physical system. Periodicity and entropy are the two opposing factors that act on it. The probability that a specific information will be processed and transmitted by the perceptual system defines its state. We view each musical syntax as a subset of a greater system that includes the different forms of western music, defining observation in three levels: sound, syntax and morphology. The final output of the model should provide a way to observe and compare the behavior of the three systems in relation to a given musical phenomena. This output depends on the probability that the present states will allow the processing of a given information.

Self-organisation, as manifest, for example, by swarms, flock, herds and other collectives, is a powerful natural force, capable of generating large and sustained structures. Yet the individuals who participate in these social groups may not even be aware of the structures that they are creating. Almost certainly, these structures emerge through the application of simple, local interactions. Improvised music is an uncertain activity, characterised by a lack of top-down organisation and busy, local activity between improvisers. Emerging structures may only be perceivable at a (temporal) distance. The development of higher-level musical structure arises from interactions at lower levels, and we propose here that the self-organisation of social animals provides a very suggestive analogy. This paper builds a model of interactivity based on stigmergy, the process by which social insects communicate indirectly by environment modification. The improvisational element of our model arises from the dynamics of a particle swarm. A process called interpretation extracts musical parameters from the aural sound environment, and uses these parameters to place attractors in the environment of the swarm, after which stigmergy can take place. The particle positions are reinterpreted as parameterised audio events. This paper describes this model and two applications, Swarm Music and Swarm Granulator.

Sixth International Conference on Computational Intelligence and Multimedia Applications (ICCIMA'05), 2005

This project investigates the use of multi-agent systems for musical accompaniment 1 . It details the construction and analysis of a percussive agent, able to add timbales accompaniment to pre-recorded salsa music. We propose, implement and test a novel representational structure directed towards latin music, and develop a music listening system designed to build up these high level representations. We develop a generative system which uses expert knowledge and high level representations to manage a set of behaviours which combine and alter templates in a musically sensitive manner.

2007

2004

This paper presents computer experiments concerning the decentralized pianola, a hypothetical mechanical music instrument, whose large-scale musical behavior is the result of local physical interactions between simple elements. Traditional mechanical music instruments like the pianola and the music box rely for their operation on the separation between a sequential memory unit and an execution unit. In a decentralized mechanical instrument, musical memory is an emergent global property of the system, undistinguishable from the execution process. Such a machine is both a score and an instrument. The paper starts by discussing the difference between sequential memory systems and systems exhibiting emergent decentralized musical behavior. Next, the use of particle system simulation for exploring virtual decentralized instruments is demonstrated, and the architecture for a simple decentralized instrument is outlined. The paper continues by describing the use of a genetic algorithm for evolving decentralized instruments that reproduce a given musical behavior.

Constructionist paradigms provide an opportunity to help learners find personal relevance and interest in originally unappealing or foreign subjects. Using constructionism as the driving force behind our design decisions, we have developed String Theory: a musical simulation app designed to generate interest driven learning across two subjects: physics and music. Through the manipulation of a string’s length, tension, and weight, students are able to explore the ways in which string instruments make a variety of notes as well as explore how physics and music are related. They can then use this knowledge to design virtual string instruments, record music, and share their work. This paper describes our design process as well as presents the future directions of String Theory.

This paper describes the incremental development of a model for interactive music -music instantiated in real-time on the basis of local performance and environmental information. Music is understood as a dynamical complex of interacting situated embodied behaviours. These behaviours may be physical or virtual, composed or emergent, or of a time scale such that they figure as constraints or constructs. All interact in the same space by a process of mutual modelling, redescription, and emergent restructuring. The model is implemented as a complex adaptive system in the Swarm simulation environment.

2011

We present a population of autonomous agents that exist within a sonic eco-system derived from real-time analysis of live audio. In this system, entitled Coming Together: Shoals, agents search for food consisting of CataRT unit analyses, which, when found, are consumed through granulation. Individual agents are initialised with random synthesis parameters, but communicate these parameters to agents in local neighborhoods.