Sound morphing by feature interpolation

The goal of sound morphing by feature interpolation is to obtain sounds whose values of features are intermediate between those of the source and target sounds. In order to do this, we should be able to resynthesize sounds that present a set of predefined feature values, a notoriously difficult problem. In this work, we present morphing techniques to obtain hybrid musical instrument sounds whose feature values correspond as close as possible to the ideal interpolated values. When the features capture perceptually relevant information, the morphed sound whose features are interpolated is perceptually intermediate. The features we use are acoustic correlates of salient timbre dimensions derived from perceptual studies, such that sounds whose feature values are intermediate between two would be placed between them in the underlying timbre space. We measure the perceptual impact of the morphed sounds directly by the feature values, using them as an objective measure with which to evaluate the results. Thus we consider that the morphed sounds change perceptually linearly when the corresponding feature values vary linearly.