Speech polarity detection using strength of impulse-like excitation extracted from speech epochs

In this paper, we address the issue of speech polarity detection using strength of impulse-like excitation around epoch. The correct detection of speech polarity is a crucial step for many speech processing algorithms to extract suitable information. Occurrence of errors in the detection of speech polarity could have an impact on the performance of speech systems. Automatic detection of speech polarity has become an important preliminary step for many speech processing algorithms. We propose a method based on the knowledge of impulse-like excitation of speech production mechanism. The impulse-like excitation is reflected across all frequencies including the zero frequency (0 Hz). Using the slope around zero crossings of the zero frequency filtered signal, an automatic speech polarity detection method is proposed. Performance of the proposed method is demonstrated on 8 different speech corpora. The proposed method is compared with the three existing techniques such as gradient of the spurious glottal waveforms (GSGW), oscillating moments-based polarity detection (OMPD) and residual excitation skewness (RESKEW). From the experimental results, it is observed that the performance of the proposed method is comparable or better than the existing methods for the experiments considered.