This preliminary study demonstrates the need for scaled algorithms capable of analyzing high-frequency recordings, which may be essential in order to gain a deeper understanding of cetacean communication. However the function of these formants and possible phonemes remains speculative. Possible "phonetic units" composed of these formants were subsequently identified. Consecutive clicks that contained regions of higher acoustic energies at approximately the same frequency were defined as formants. While the STFT spectrograms did not portray the regions of local energy maxima within each click clearly, the Gabor scalogram displayed distinct bands of local energy maxima with respect to frequency. The resulting scalograms were visually inspected. Click data collected from bottlenose dolphins (Tursiops sp.) sampled at 96 kHz and 500 kHz were analyzed using both the STFT and Gabor scalogram. We propose to use Gabor wavelet decomposition to get better local energy maxima contrast instead of the Fourier STFT. The short time Fourier transform (STFT) is characterized by a time-frequency trade-off, resulting in difficulty in ascertaining local energy maxima within a short-duration click. Determining the power spectrum within a click may help differentiate clicks and their possible communicative functions. Toothed whales (suborder: Odontoceti) produce high-frequency clicks for navigation and possibly communication.
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