Quantitative Tools for Examining the Vocalizations of Juvenile Songbirds
Figure 3
(a) Using a discrete Fourier transform, sounds are converted from waveform (top pane) to a sequence of frequency spectra (bottom pane)—in essence, a spectrogram. Note that each discrete frequency spectrum accounts for a period of time much larger than the sampling rate; the effect is exaggerated here to make this clear. (b) Examples of possible prototypes. In the WSPR algorithm, every segment of sound will be matched to a similar prototype and coded as the prototype’s index number (1, 2, 3, 4, etc.)
