Abstract
In this paper, a psychologically-inspired binary cascade classification schema is proposed for speech emotion recognition. Performance is enhanced because commonly confused pairs of emotions are distinguishable from one another. Extracted features are related to statistics of pitch, formants, and energy contours, as well as spectrum, cepstrum, perceptual and temporal features, autocorrelation, MPEG-7 descriptors, Fujisaki’s model parameters, voice quality, jitter, and shimmer. Selected features are fed as input to K nearest neighborhood classifier and to support vector machines. Two kernels are tested for the latter: linear and Gaussian radial basis function. The recently proposed speaker-independent experimental protocol is tested on the Berlin emotional speech database for each gender separately. The best emotion recognition accuracy, achieved by support vector machines with linear kernel, equals 87.7%, outperforming state-of-the-art approaches. Statistical analysis is first carried out with respect to the classifiers’ error rates and then to evaluate the information expressed by the classifiers’ confusion matrices.
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Acknowledgements
M. Kotti would like to thank Associate Professor Constantine Kotropoulos for his valuable contributions for the extraction of part of the features that are described in Sect. 4.
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This work was carried out during the tenure of an ERCIM “Alain Bensoussan” Fellowship Programme.
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Kotti, M., Paternò, F. Speaker-independent emotion recognition exploiting a psychologically-inspired binary cascade classification schema. Int J Speech Technol 15, 131–150 (2012). https://doi.org/10.1007/s10772-012-9127-7
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DOI: https://doi.org/10.1007/s10772-012-9127-7