compared with the tonal model. This allows us to recommend the use of the developed model in the program of automatic harmonization of melodies. The contribution of the study to the theory of genetic algorithms is in creation of the new approach to the formation of chromosomes and a multi-factorial quality function, which made it possible to effectively apply genetic algorithms to the task of harmonizing music. The practical significance of the research results consists in automation of the composer work who can concentrate entirely on the creation of a melody. The task of harmonizing the melody with chords can be assigned to a computer. In addition, the obtained high speed of harmonization allows improving the quality of the generated melodies and their compliance with the dynamic situations in computer games.

The problem of musical accompaniment harmonization for adjacent transitional fragments in computer games is considered. A harmonization method based on a tonal model of the musical composition in conjunction with a genetic algorithm seeking the global extremum of the harmonic function is proposed. For the method under consideration, all operators of the genetic algorithm and fitness functions are defined. A scheme was developed for the formation of transitional musical compositions and a flowchart was proposed for using the genetic algorithm in its implementation. Using examples of well-known musical compositions, a study was conducted of the genetic algorithm features and its most appropriate parameters were found in the context of the problem under consideration. This allowed us to obtain expression for the computational costs of the proposed method, which are necessary for balancing the computational load in the computer between the game algorithm itself and the musical harmonization algorithm. Moreover, the study showed that using genetic algorithm allows even for a small number of iterations to achieve melody harmonization level no worse than professional composer achieved, and even exceed this level when performing extra iterations.