Playing Technique Classification Based on Deep Collaborative Learning of Variational Auto-Encoder and Gaussian Process

Modeling musical timbre is critical for various music information retrieval (MIR) tasks. This work addresses the task of classifying playing techniques, which involves extremely subtle variations of timbre among different categories. A deep collaborative learning framework is proposed to represent a music with greater discriminative power than previously achieved. Firstly, a novel variational autoencoder (VAE) is developed to eliminate the variation of acoustic features within a class. Secondly, a Gaussian process classifier is jointly learned to distinguish the variations of timbres between classes, which increases the discriminative power of the learned representations. We derive a new lower bound that guides a VAE-based representation. Experiments were conducted on a database of seven classes of guitar playing techniques. The experimental results demonstrated that the proposed method outperforms baselines in terms of the Fl-score and accuracy.