Evaluation of delexicalization methods for research on emotional speech

Perceptual evaluation of non-controlled emotional speech requires delexicalization to neutralize semantic variation. However, most existing methods imply losing spectral cues crucial to emotional attribution, related to both laryngeal and supralaryngeal settings. We propose a method relying on voice morphing to retain part of the spectral information of the original stimuli, as an additional step to diphone synthesis delexicalization. After previous assessment of intelligibility loss, this study evaluates the naturalness of angry and neutral expressions in French films, delexicalized using low-pass filtering and the proposed method implemented with MBROLA and STRAIGHT. Results show that morphing-based delexicalization, which leads to accurate emotional attribution, is rated with a higher degree of naturalness than low-pass filtering. Implications for research in affective speech are discussed with regards to other delexicalization methods proposed in the literature

Cross-Linguistic Distinctions Between Professional and Non-Professional Speaking Styles

International audiencelong story and narrated it subsequently. All this material was obtained in four language varieties: Brazilian and European Portuguese, standard French and German. The corpus is balanced for gender. Eight melodic and intensity parameters were automatically obtained from excerpts of 10 to 20 seconds. We showed that 6 out of 8 parameters partially distinguish professional from non-professional style in the four language varieties. Classification and discrimination tests carried out with 12 Brazilian listeners using delexicalised speech showed that these subjects are able to distinguish professional style from non-professional style with about 2/3 of hits irrespective of language. In comparison, an automatic classification using an LDA model performed better in classifying non-professional (96 %) against professional styles, but not in classifying professional (42 %) against non-professional styles