Time-Frequency Display of Electroacoustic Data Using Cycle-Octave Wavelet Transforms
A cycle-octave time-frequency display is created by plotting the magnitude of the wavelet transform, using a Morlet complex Gaussian wavelet on a log-frequency scale versus time in number of cycles of the wavelet's center frequency. This type of display is quite well suited to plotting the decay response of wide-band systems, such as the impulse response of a loudspeaker, because the time scale is long at low frequencies and short at high frequencies. If the response of typical filters is plotted on this display, the resultant 3-D responses are independent of the filter's center frequency, i.e., the decay response shape of a particular filter remains the same as its center frequency is shifted up and down in log frequency.
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