Abstract
Speech emotional content estimation is still a challenge for building robust human–machine interaction systems. Accuracy of emotion estimation depends upon the corpus used for training and the acoustic features employed for modelling the speech signal. Generally, emotion estimation is computationally expensive, and hence, there is a need of developing alternative techniques. In this paper, a low complexity fractal-based technique has been explored. Our hypothesis is that fractal analysis would provide better emotional content estimation because of the nonlinear nature of the speech signals. Fractal analysis involves two important parameters, i.e. fractal dimension and loop area. Fractal dimension has been computed using the Katz algorithm. The investigations using a GMM-based model show that the proposed technique is capable of identifying the emotional content within the given speech signals reliably and accurately. Further, the technique is robust in the sense that it can bear the noise level in the signal up to 10 dB. The analysis also shows that the technique is gender insensitive. The scope of the investigations presented here is limited to phonemic-level analysis, although the technique works efficiently with speech phrases as well.
Similar content being viewed by others
Data Availability
The data generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
References
Z. Ali, M. Talha, Innovative method for unsupervised voice activity detection and classification of audio segments. IEEE Access 6, 15494–15504 (2018)
P.N. Baljekar. H.A. Patil, A comparison of waveform fractal dimension techniques for voice pathology classification. in Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), (2012), pp. 4461–4464
G. Bandoin, Y. Stylianou, On the transformation of the speech spectrum for voice conversion. in Proceedings of the 4th International Conference on Spoken Language Processing ICSLP, (1996)
A. Barbulescu, C. Serban, C. Maftei, Evaluation of hurst exponent for precipitation time series. in Proceedings of the 14th WSEAS International Conference on Computers, (2010), pp. 590–595
P. Castiglioni, What is wrong in Katz’s method? comments on: a note on fractal dimensions of biomedical waveforms. Comput. Biol. Med. 40(11–12), 950–952 (2010)
P. Chandrasekar, S. Chapaneri, D. Jayaswal, Automatic speech emotion recognition: a survey. in Proc. Circuits, Systems, Communication and Information Technology Applications (CSCITA), (2014), pp. 341–346
M. Chen, X. He, J. Yang, H. Zhang, 3-D Convolutional recurrent neural networks with attention model for speech emotion recognition. IEEE Signal Process. Lett. 25(10), 1440–1444 (2018)
M. Chen, P. Zhou, G. Fortino, Emotion communication system. IEEE Access 5, 326–337 (2017)
K. Dupuis, M.K. Pichora-Fuller, Toronto Emotional Speech Set (TESS) (Psychology Department, University of Toronto, Toronto, 2010).
M. ElAyadi, M.S. Kamel, F. Karray, Survey on speech emotion recognition: features, classification schemes, and databases. Pattern Recognit. 44(3), 572–587 (2011)
R. Esteller, G. Vachtsevanos, J. Echauz, B. Litt, A comparison of waveform fractal dimension algorithms. Trans. Circuits Syst. I Fundam. Theory Appl. 48(2), 177–183 (2001)
A.M. Fahim, A.M. Salem, F.A. Torkey, M.A. Ramadan, An efficient enhanced k-means clustering algorithm. J. Zhejiang Univ Sci 7, 1626–1633 (2006)
K. Han, D. Yu, I. Tashev, Speech emotion recognition using deep neural network and extreme learning machine. Proceedings of the Fifteenth Annual Conference of the International Speech Communication Association (INTERSPEECH), (2014), pp. 223–227
M. N. Hasrul, M. Hariharan, S. Yaacob, Human Affective (Emotion) behaviour analysis using speech signals: A review. in, 2012 International Conference on Biomedical Engineering (ICoBE), (2012), pp. 27–28
T. Higuchi, Approach to an irregular time series on the basis of the fractal theory. Phys. D 31, 277–283 (1988)
R. Hokking, K. Woraratpanya, and Y. Kuroki, Speech recognition of different sampling rates using fractal code descriptor. in, IEEE International Joint Conference on Computer Science and Software Engineering (JCSSE), (2016), pp. 1–5
H. Hu, M.X. Xu, W. Wu, GMM supervector based SVM with spectral features for speech emotion recognition. in, Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), (2007), pp. 413–416
G. Julia, Memoire sur l’iteration des fonctions rationnelles. J. Math. Pures Appl. 8, 47–245 (1918)
M.J. Katz, Fractals and the analysis of waveforms. Comput. Biol. Med. 18(3), 145–156 (1988)
S.G. Koolagudi, K.S. Rao, Emotion recognition from speech: a review. Int. J. Speech Tech. 15(2), 99–117 (2012)
W.J.M. Levelt, Models of word production. Trends Cogn. Sci. 3(6), 223–232 (1999)
G. Tamulevicius, R. Karbauskaite, G. Dzemyda, Selection of fractal dimension features for speech emotion classification. in, IEEE Open Conference of Electrical, Electronic and Information Sciences (eStream), (2017), pp. 1–4
R. Lopes, N. Betrouni, Fractal and multifractal analysis: a review. Med. Image Anal. 13(4), 634–649 (2009)
P.C. Mahalanobis, On the generalized distance in statistics. in, Proceeding of the National Institute of Sciences of India, (1936), pp. 49–55
B.B. Mandelbrot, The Fractal Geometry of Nature (Henry Holt and Company, New York, 1983).
Q. Mao, M. Dong, Z. Huang, Y. Zhan, Learning salient features for speech emotion recognition using convolutional neural networks. IEEE Trans. Multimed. 16(8), 2203–2213 (2014)
P. Maragos, Fractal aspects of speech signals: dimension and interpolation. in, Proceeding of IEEE International Conference on Acoust., Sp. and Sig. Proc. (ICASSP), (1991), pp. 417–420
A.K. Mishra, S. Raghav, Local fractal dimension based ECG arrhythmia classification. Biomed. Signal Process Control 5(2), 114–123 (2010)
J.S. Park, S.H. Kim, Emotion recognition from speech signals using fractal features. Int. J. Soft Eng. Appl. 8(5), 15–22 (2014)
S. Peleg, J. Naor, R. Hartley. D. Avnir, Multiple resolution texture analysis and classification. in, 4th Jerusalem Conference on Information Technology, (1984), pp. 483–488
A. Petrosian, Kolmogorov complexity of finite sequences and recognition of different preictal EEG patterns. in, Proceedings eighth IEEE symposium on computer-based medical systems, (1995), pp. 212–217
J. Rong, G. Li, Y.P.P. Chen, Acoustic feature selection for automatic emotion recognition from speech. Inf. Process. Manag. 45(3), 315–328 (2009)
T.R. Senevirathne, E.L.J. Bohez, J.A. Van Winden, Amplitude scale method: new and efficient approach to measure fractal dimension of speech waveforms. Electron. Lett. 28(4), 420–422 (1992)
J.B. Singh, P. Lehana, Emotional speech analysis using harmonic plus noise model and Gaussian mixture model. Int. J. Speech Technol. 22(3), 483–496 (2019)
J.B. Singh, P. Lehana, Straight-based emotion conversion using quadratic multivariate polynomial. Circuits Syst. Signal Process. 37(5), 2179–2193 (2018)
P. Song, W. Zheng, Feature selection based transfer subspace learning for speech emotion recognition. IEEE Trans. Affect. Comput. 11(3), 373–382 (2018)
K.P. Truong, D.A. Leeuwen, Automatic discrimination between laughter and speech. Speech Commun. 49(2), 114–158 (2007)
T. Vogt, E. Andre, J. Wagner, Automatic recognition of emotions from speech: a review of the literature and recommendations for practical realisation. in, Affect and Emotion in Human-Computer Interaction: From Theory to Appl, (2008), pp. 75–91
Z. Zeng, M. Pantic, G.I. Roisman, T.S. Huang, A survey of affect recognition methods: audio, visual, and spontaneous expressions. IEEE Trans. Pattern Anal. Mach. Intell. 31(1), 39–58 (2009)
S. Zhang, S. Zhang, T. Huang, W. Gao, Speech emotion recognition using deep convolutional neural network and discriminant temporal pyramid matching. IEEE Trans. Multimed 20(6), 1576–1590 (2018)
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Abrol, A., Kapoor, N. & Lehana, P.K. Fractal-Based Speech Analysis for Emotional Content Estimation. Circuits Syst Signal Process 40, 5632–5653 (2021). https://doi.org/10.1007/s00034-021-01737-2
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00034-021-01737-2