fspec {bioacoustics} | R Documentation |
This function returns the spectrographic representation of a time wave in the absolute scale or in decibels (dB) using the Fast Fourier transform (FFT).
fspec( wave, channel = "left", FFT_size = 256, FFT_overlap = 0.875, FFT_win = "hann", LPF, HPF = 0, tlim = NULL, flim = NULL, rotate = FALSE, to_dB = TRUE )
wave |
a Wave object. |
channel |
character. Channel to keep for analysis in a stereo recording: "left" or "right". Default setting is left. |
FFT_size |
integer. Size of the Fast Fourrier Transform (FFT) window. Default setting is 256. |
FFT_overlap |
numeric. Percentage of overlap between two FFT windows (from 0 to 1). Default setting is 0.875. |
FFT_win |
character. Specify the type of FFT window: "hann", "blackman4", or "blackman7". Default setting is "hann". |
LPF |
integer. Low-Pass Filter (Hz). Frequencies above the cutoff are greatly attenuated. Default setting is the Nyquist frequency of the recording. |
HPF |
integer. High-Pass Filter (Hz). Frequencies below the cutoff are greatly attenuated. Default setting is 0 Hz. |
tlim |
numeric. Specify the time limits on the X-axis in seconds (s).
Default setting is |
flim |
numeric. Specify the frequency limits on the Y-axis in Hz. Default
setting is |
rotate |
logical. Should the matrix be rotated 90° counter clockwise ?
Default setting is |
to_dB |
logical. Convert magnitude values to decibels (dB)? Default is |
A matrix of amplitude or decibel (dB) values in the time / frequency domain.
data(myotis) image(fspec(myotis, tlim = c(1, 2), rotate = TRUE))