Spectrogram layer of dynamic spectrograms

ds_spectrogram() adds a spectrogram to a dynaspec() object and sets how it is computed and drawn. Adding it again changes its settings.

Usage

ds_spectrogram(wl, ovlp, wn, pal, collevels, colbg, amp.trans, ...)

wl: Window length (in samples), as in seewave::spectro().
ovlp: Percent overlap between consecutive windows, as in seewave::spectro().
wn: Window function name, as in seewave::spectro() (e.g. "hanning" or "blackman").
pal: Color palette function (e.g. viridis::viridis() or seewave::reverse.gray.colors.1()). Paged spectrograms also take the names of 'viridis' palettes (e.g. "magma") and 2 colors for a gradient (e.g. c("white", "black")).
collevels: Numeric vector with the amplitude levels (in dB) of the colors, as in seewave::spectro() (e.g. seq(-40, 0, 1)).
colbg: Background color of the spectrogram, shown where the amplitude is below the lowest level of 'collevels'. Default is the color of the lowest amplitude of the palette (e.g. white for seewave::reverse.gray.colors.1(), the default palette, or dark blue for viridis::mako()), so quiet parts and the background look the same.
amp.trans: Amplitude transformation to brighten paged spectrograms (values > 1 brighten quiet sounds; only used by ds_paged()).
...: Additional arguments passed to seewave::spectro().

A layer to be added to a dynaspec() object with +.

Only the arguments supplied are used; other settings take the defaults of each style (see ds_scrolling(), ds_paged() and ds_static()).

data(scythebill)

x <- dynaspec(scythebill, flim = c(1.5, 5.5)) +
  ds_spectrogram(wl = 200, pal = viridis::mako, collevels = seq(-60, 0, 1))