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Draw spectrograms

Source: R/draw_spectrogram.R
draw_spectrogram.Rd

This function was slightly changed from phonTools::spectrogram(). Argument description is copied from phonTools::spectrogram().

Usage

draw_spectrogram(
  sound,
  fs = 22050,
  text_size = 1,
  window_length = 5,
  dynamic_range = 50,
  window = "kaiser",
  windowparameter = -1,
  freq_scale = "kHz",
  spectrum_info = TRUE,
  timestep = -1000,
  padding = 10,
  preemphasisf = 50,
  frequency_range = c(0, 5),
  nlevels = dynamic_range,
  x_axis = TRUE,
  title = NULL,
  raven_annotation = NULL,
  formant_df = NULL
)

Arguments

sound

Either a numeric vector representing a sequence of samples taken from a sound wave or a sound object created with the loadsound() or makesound() functions.

fs

The sampling frequency in Hz. If a sound object is passed this does not need to be specified.

text_size

numeric, text size (default = 1).

window_length

The desired analysis window length in milliseconds.

dynamic_range

Values greater than this many dB below the maximum will be displayed in the same color.

window

A string indicating the type of window desired. Supported types are: rectangular, hann, hamming, cosine, bartlett, gaussian, and kaiser.

windowparameter

The parameter necessary to generate the window, if appropriate. At the moment, the only windows that require parameters are the Kaiser and Gaussian windows. By default, these are set to 2 for kaiser and 0.4 for gaussian windows.

freq_scale

a string indicating the type of frequency scale. Supported types are: "Hz" and "kHz".

spectrum_info

logical. If TRUE then add information about window method and params.

timestep

If a negative value is given, -N, then N equally-spaced time steps are calculated. If a positive number is given, this is the spacing between adjacent analyses, in milliseconds.

padding

The amount of zero padding for each window, measured in units of window length. For example, if the window is 50 points, and padding = 10, 500 zeros will be appended to each window.

preemphasisf

Preemphasis of 6 dB per octave is added to frequencies above the specified frequency. For no preemphasis, set to a frequency higher than the sampling frequency.

frequency_range

vector with the range of frequencies to be displayed for the spectrogram up to a maximum of fs/2. This is set to 0-5 kHz by default.

nlevels

The number of divisions to be used for the z-axis of the spectrogram. By default it is set equal to the dynamic range, meaning that a single color represents 1 dB on the z-axis.

x_axis

If TRUE then draw x axis.

title

Character with the title.

raven_annotation

Raven (Center for Conservation Bioacoustics) style annotations (boxes over spectrogram). The dataframe that contains time_start, time_end, freq_low and freq_high columns. Optional columns are colors and content.

formant_df

dataframe with formants from formant_to_df() function

Value

Plot the comptued spectrogram

Author

Santiago Barreda <sbarreda@ucdavis.edu>

Examples

# \donttest{
draw_spectrogram(system.file("extdata", "test.wav",
  package = "phonfieldwork"
))

# }