Emotions recognition in audio signals using an extension of the latent block model

Abstract

Emotion detection in human speech is a significant area of research, crucial for various applications such as affective computing and human–computer interaction. Despite advancements, accurately categorizing emotional states in speech remains challenging due to its subjective nature and the complexity of human emotions. To address this, we propose leveraging Mel frequency cepstral coefficients (MFCCS) and extend the latent block model (LBM) probabilistic clustering technique with a Gaussian multi-way latent block model (GMWLBM). Our objective is to categorize speech emotions into coherent groups based on the emotional states conveyed by speakers. We employ MFCCS from time-series audio data and utilize a variational Expectation Maximization method to estimate GMWLBM parameters. Additionally, we introduce an integrated Classification Likelihood (ICL) model selection criterion to determine the optimal number of clusters, enhancing robustness. Numerical experiments on real data from the Berlin Database of Emotional Speech (EMO-DB) demonstrate our method’s efficacy in accurately detecting and classifying emotional states in human speech, even in challenging real-world scenarios, thereby contributing significantly to affective computing and human–computer interaction applications.