soundgen (version 2.6.2)

fade: Fade

Description

Applies fade-in and/or fade-out of variable length, shape, and steepness. The resulting effect softens the attack and release of a waveform.

Usage

fade(
  x,
  fadeIn = 50,
  fadeOut = 50,
  fadeIn_points = NULL,
  fadeOut_points = NULL,
  samplingRate = NULL,
  scale = NULL,
  shape = c("lin", "exp", "log", "cos", "logistic", "gaussian")[1],
  steepness = 1,
  reportEvery = NULL,
  cores = 1,
  saveAudio = NULL,
  plot = FALSE,
  savePlots = NULL,
  width = 900,
  height = 500,
  units = "px",
  res = NA,
  ...
)

Value

Returns a numeric vector of the same length as input

Arguments

x

path to a folder, one or more wav or mp3 files c('file1.wav', 'file2.mp3'), Wave object, numeric vector, or a list of Wave objects or numeric vectors

fadeIn, fadeOut

length of segments for fading in and out, ms (0 = no fade)

fadeIn_points, fadeOut_points

length of segments for fading in and out, points (if specified, override fadeIn/fadeOut)

samplingRate

sampling rate of x (only needed if x is a numeric vector)

scale

maximum possible amplitude of input used for normalization of input vector (only needed if x is a numeric vector)

shape

controls the type of fade function: 'lin' = linear, 'exp' = exponential, 'log' = logarithmic, 'cos' = cosine, 'logistic' = logistic S-curve

steepness

scaling factor regulating the steepness of fading curves (except for shapes 'lin' and 'cos'): 0 = linear, >1 = steeper than default

reportEvery

when processing multiple inputs, report estimated time left every ... iterations (NULL = default, NA = don't report)

cores

number of cores for parallel processing

saveAudio

full path to the folder in which to save audio files (one per detected syllable)

plot

if TRUE, produces an oscillogram of the waveform after fading

savePlots

full path to the folder in which to save the plots (NULL = don't save, '' = same folder as audio)

width, height, units, res

graphical parameters for saving plots passed to png

...

other graphical parameters

See Also

crossFade

Examples

#' # Fading a real sound: say we want fast attack and slow release
s = soundgen(attack = 0, windowLength = 10,
             sylLen = 500, addSilence = 0)
# playme(s)
s1 = fade(s, fadeIn = 40, fadeOut = 350,
          samplingRate = 16000, shape = 'cos', plot = TRUE)
# playme(s1)

# Illustration of fade shapes
x = runif(5000, min = -1, max = 1)  # make sure to zero-center input!!!
# plot(x, type = 'l')
y = fade(x, fadeIn_points = 1000, fadeOut_points = 0, plot = TRUE)
y = fade(x, fadeIn_points = 1000, fadeOut_points = 1500,
         shape = 'exp', steepness = 1, plot = TRUE)
y = fade(x, fadeIn_points = 1500, fadeOut_points = 500,
         shape = 'log', steepness = 1, plot = TRUE)
y = fade(x, fadeIn_points = 1500, fadeOut_points = 500,
         shape = 'log', steepness = 3, plot = TRUE)
y = fade(x, fadeIn_points = 1500, fadeOut_points = 1500,
         shape = 'cos', plot = TRUE)
y = fade(x, fadeIn_points = 1500, fadeOut_points = 1500,
         shape = 'logistic', steepness = 1, plot = TRUE)
y = fade(x, fadeIn_points = 1500, fadeOut_points = 1500,
         shape = 'logistic', steepness = 3, plot = TRUE)
y = fade(x, fadeIn_points = 1500, fadeOut_points = 1500,
         shape = 'gaussian', steepness = 1.5, plot = TRUE)

if (FALSE) {
  fade('~/Downloads/temp', fadeIn = 500, fadeOut = 500, savePlots = '')
}