reverb: Reverb & echo

View source: R/postprocessing.R

reverbR Documentation

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)

soundgen documentation built on Aug. 14, 2022, 5:05 p.m.