A perceptual and affective evaluation of an affectively driven engine for video game soundtracking

We report on a player evaluation of a pilot system for dynamic video game soundtrack generation. The system being evaluated generates music using an AI-based algorithmic composition technique to create score in real-time, in response to a continuously varying emotional trajectory dictated by gameplay cues. After a section of gameplay, players rated the system on a Likert scale according to emotional congruence with the narrative, and also according to their perceived immersion with the gameplay. The generated system showed a statistically meaningful and consistent improvement in ratings for emotional congruence, yet with a decrease in perceived immersion, which might be attributed to the marked difference in instrumentation between the generated music, voiced by a solo piano timbre, and the original, fully orchestrated soundtrack. Finally, players rated selected stimuli from the generated soundtrack dataset on a two-dimensional model reflecting perceived valence and arousal. These ratings were compared to the intended emotional descriptor in the meta-data accompanying specific gameplay events. Participant responses suggested strong agreement with the affective correlates, but also a significant amount of inter-participant variability. Individual calibration of the musical feature set, or further adjustment of the musical feature set are therefore suggested as useful avenues for further work