reverb: Reverb & echo

In tatters/soundgen: Sound Synthesis and Acoustic Analysis

Reverb & echo

Description

Adds reverberation and/or echo to a sound. Algorithm for reverb: adds time-shifted copies of the signal weighted by a decay function, which is analogous to convoluting the input with a parametric model of some hypothetical impulse response function. In simple terms: we specify how much and when the sound rebounds back (as from a wall) and add these time-shifted copies to the original, optionally with some spectral filtering.

Usage

reverb(
  x,
  samplingRate = NULL,
  echoDelay = 200,
  echoLevel = -20,
  reverbDelay = 70,
  reverbSpread = 130,
  reverbLevel = -25,
  reverbDensity = 50,
  reverbType = "gaussian",
  filter = list(),
  dynamicRange = 80,
  output = c("audio", "detailed")[1],
  play = FALSE,
  reportEvery = NULL,
  cores = 1,
  saveAudio = NULL
)

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
samplingRate	sampling rate of x (only needed if x is a numeric vector)
echoDelay	the delay at which the echo appears, ms
echoLevel	the rate at which the echo weakens at each repetition, dB
reverbDelay	the time of maximum reverb density, ms
reverbSpread	standard deviation of reverb spread around time reverbDelay, ms
reverbLevel	the maximum amplitude of reverb, dB below input
reverbDensity	the number of echos or "voices" added
reverbType	so far only "gaussian" has been implemented
filter	(optional) a spectral filter to apply to the created reverb and echo (see addFormants for acceptable formats)
dynamicRange	the precision with which the reverb and echo are calculated, dB
output	"audio" = returns just the processed audio, "detailed" = returns a list with reverb window, the added reverb/echo, etc.
play	if TRUE, plays the processed audio
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 folder for saving the processed audio; NULL = don't save, ” = same as input folder (NB: overwrites the originals!)

Examples

s = soundgen()
s_rev = reverb(s, 16000)
# playme(s_rev)

## Not run: 
# double echo, no reverb
s1 = reverb(s, samplingRate = 16000, reverbLevel = NULL,
            echoDelay = c(250, 800), echoLevel = c(-15, -25))
# playme(s1)
# spectrogram(s1, 16000, osc = TRUE, ylim = c(0, 4))

# only reverb (indoors)
s2 = reverb(s, samplingRate = 16000, echoDelay = NULL,
            reverbDelay = 70, reverbSpread = 130,
            reverbLevel = -20, reverbDensity = 20)
# playme(s2)
# spectrogram(s2, 16000, osc = TRUE, ylim = c(0, 4))

# reverb (caves)
s3 = reverb(s, samplingRate = 16000, echoDelay = NULL,
            reverbDelay = 600, reverbSpread = 1500,
            reverbLevel = -10, reverbDensity = 100)
# playme(s3)
# spectrogram(s3, 16000, osc = TRUE, ylim = c(0, 4))

# both echo and reverb with high frequencies emphasized
s4 = reverb(s, samplingRate = 16000,
            echoDelay = 250, echoLevel = -20,
            reverbDelay = 70, reverbSpread = 120,
            reverbLevel = -25, reverbDensity = 50,
            filter = list(formants = NULL, lipRad = 3))
# playme(s4)
# spectrogram(s4, 16000, osc = TRUE, ylim = c(0, 4))

# add reverb to a recording
s5 = reverb('~/Downloads/temp260/ut_fear_57-m-tone.wav',
            echoDelay = 850, echoLevel = -40)
# playme(s5, 44100)

# add reverb to all files in a folder, save the result
reverb('~/Downloads/temp2', saveAudio = '~/Downloads/temp2/rvb')

## End(Not run)

tatters/soundgen documentation built on Aug. 22, 2023, 4:24 p.m.