phonTools (version 0.2-0)

spectralslice: Spectral Slice

Description

A function to plot the spectrum of a vector representing a sound wave.

Usage

spectralslice (sound, padding = length(sound) * 2, fs = 22050,  
show = TRUE, color = 1, add = FALSE, xlim, ylim, window = "kaiser",	
windowparameter = 3, zeromax = TRUE, preemphasisf = 0, type, xlab, pwr = FALSE, 
line = FALSE,...)

Arguments

sound

A vector representing a sound wave, or a 'sound' object.

padding

The amount of zero-padding desired for the analysis.

fs

The sampling frequency of the sound. If a 'sound' object is passed this does not need to be specified.

show

If FALSE, no plot is created.

color

Set the color used for plotting the spectrum.

add

If TRUE, the spectrum is added to an existing plot. If FALSE a new one is created.

xlim

The range of frequencies to be plotted. By default the function will plot from 0 Hz to fs/2 Hz.

ylim

The y axis (power/magnitude) range to plot.

window

The window to be applied to the signal, applied by windowfunc(), provided in this package.

windowparameter

The parameter for the window to be applied to the signal, if appropriate. Passed to windowfunc().

zeromax

If TRUE, the maximum dB is set to 0.

type

The line type to be used for plotting, passes its value to the 'lty' parameter.

preemphasisf

Preemphasis of 3 dB per octave is added to frequencies above the specified frequency.

xlab

the x-axis label may be specified if desired.

pwr

If TRUE, a power spectrum is calculated, if FALSE, a magnitude spectrum is calculated.

line

If TRUE, a line spectrum is created.

...

any additional arguments will be passed to the internal calls of 'plot' or 'lines'.

Value

• A dataframe with the following elements is returned:
• hz
  The center frequency of the analysis bins.
• dB
  The dB magnitude/power for the analysis bin.

Details

This function can be used to calculate and plot short-time discrete spectra for sections of signals.

Examples

data (sound)
par (mfrow = c(2,2))

spectralslice (sound$sound[11000:11200], padding = 0, xlim = c(0,5000), 
               main = 'few points, no padding')
spectralslice (sound$sound[11000:11600], padding = 0, xlim = c(0,5000), 
               main = 'many points, no padding')

spectralslice (sound$sound[11000:11200], padding = 5000, xlim = c(0,5000), 
               main = 'few points, with padding')
spectralslice (sound$sound[11000:11600], padding = 5000, xlim = c(0,5000), 
               main = 'many points, with padding')

## line spectrum
spectralslice (sound$sound[11000:11100], padding = 0, line = TRUE, xlim = c(0,5000))