Proceedings IX CIM 1991, Genova, November 13-16 - AIMI

HARP: UN AMBIENTE AD ALTO LIVELLO
PER L'AUSILIO ALLA COMPOSIZIONE
A.Camurri, C.Canepa, M.Frixione, C.Innocenti, C.Massucco, R.Zaccaria
DIST - Universitddi Genova
Laboratorio di Informatica Musicale
Via Opera Pia lIlA - 16145 Genova
posta elettronica: music@dist.dist.unige.it
Abstract
This paper describes a methodological framework and a prototype high-level system called HARP
(Hybrid Action Representation and Planning) [3, 4]. HARP is designed to store and process music
and sounds, and to carry out plans for manipulating this material according to the composer's goals.
Therefore, it is able to help in the development of new music pieces as well as in manipulating
existent ones, on the basis of given material: to this end, the system provides also formal analysis
capabilities on both music and sounds; for extracting information useful in subsequent synthesis
processes. In other words, HARP is a system for the representation and manipulation of music
knowledge as regards composition: this is a vast field of knowledge which can be suitably managed
by a twofold formalism. The sound itself (samples, codes, algorithms), real-time performance,
particular analysis processes, are managed by procedures, included in an object-oriented concurrent
environment (HARP analogical subsystem). Higher level scores, composition rules, definitions in
general, descriptions of pieces of music, are stored in a declarative symbolic environment (HARP
symbolic subsystem), based on a multiple-inheritance semantic network formalism derived from KL­
ONE [2], that we have extended to represent time, a fundamental aspect of music knowledge [5,6]. A
formal link between the two subsystems exists, so that, for example, asking the semantic network to
generate a particular instance of a music object, automatically "fires" the appropriate procedures at the
analogical level.
A software prototype has been implemented using Arity Prolog and Microsoft C on PC-IBM under
the Microsoft Windows SDK environment.
1. Introduzione
Sistemi informatici per l'ausilio alla composizione sono generalmente basati su strumenti e
linguaggi per la manipolazione a basso livello di suoni, partiture ed algoritmi [I]. Recenti proposte
basate su linguaggi orientati agli oggetti [7] e su tecniche di intelligenza artificiale [5, 6] sono
orientate alla definizione di formalismi piu efficaci e ad alto livello.
Nell'articolo viene introdotto un formalismo basato su tecniche di Intelligenza Artificiale,
denominato HARP (Hybrid Action Representation and Planning), per la memorizzazione e la
manipolazione ad alto livello sia di musica (partiture, descrizioni a diversi livelli di astrazione del
materiale musicale) che di suoni. Tale formalismo e inoltre in grado di gestire la pianificazione di
azioni complesse per la manipolazione di suoni e musica in funzione di obiettivi specificati dal
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