auto_realign: Fix small misalignments in the time position test sounds

In maRce10/baRulho: Quantifying (Animal) Sound Degradation

Fix small misalignments in the time position test sounds

Description

auto_realign fixes small misalignments in the time position of test sounds in an extended selection table using spectrographic cross-correlation

Usage

auto_realign(
  X,
  Y,
  cores = getOption("mc.cores", 1),
  pb = getOption("pb", TRUE),
  hop.size = getOption("hop.size", 11.6),
  wl = getOption("wl", NULL),
  ovlp = getOption("ovlp", 90),
  wn = c("hanning", "hamming", "bartlett", "blackman", "flattop", "rectangle")
)

Arguments

X	object of class 'extended_selection_table' created by the function selection_table from the warbleR package. The object must include the following additional columns: 'sound.id', 'bottom.freq' and 'top.freq'.
Y	object of class 'extended_selection_table' (a class created by the function selection_table from the warbleR package) with the master sound file annotations. This should be the same data than that was used for finding the position of markers in find_markers. It should also contain a 'sound.id' column.
cores	Numeric vector of length 1. Controls whether parallel computing is applied by specifying the number of cores to be used. Default is 1 (i.e. no parallel computing).
pb	Logical argument to control if progress bar is shown. Default is TRUE.
hop.size	A numeric vector of length 1 specifying the time window duration (in ms). Default is 11.6 ms, which is equivalent to 512 wl for a 44.1 kHz sampling rate. Ignored if 'wl' is supplied.
wl	a vector with a single even integer number specifying the window length of the spectrogram, default is NULL. If supplied, 'hop.size' is ignored. Odd integers will be rounded up to the nearest even number.
ovlp	Numeric vector of length 1 specifying the percentage of overlap between two consecutive windows, as in spectro. Default is 90. High values slow down the function but produce more accurate results.
wn	A character vector of length 1 specifying the window name as in ftwindow.

Details

Precise alignment is crucial for downstream measures of sound degradation. This function uses spectrographic cross-correlation to align the position in time of test sounds. The master sound file is used as reference. The function calls warbleR's cross_correlation internally to align sounds using cross-correlation. The output extended selection table contains the new start and end values after alignment. Note that this function only works to further improve alignments if the estimated position of the test sound is already close to the actual position. Note that both 'X' and 'Y' must be extended selection tables sensu selection_table.

Value

Object 'X' in which time parameters (columns 'start' and 'end') have been tailored to more closely match the start and end of the reference sound.

Author(s)

Marcelo Araya-Salas ([e-mail])

References

Araya-Salas, M. (2020). baRulho: baRulho: quantifying degradation of (animal) acoustic signals in R. R package version 1.0.2

Clark, C.W., Marler, P. & Beeman K. (1987). Quantitative analysis of animal vocal phonology: an application to Swamp Sparrow song. Ethology. 76:101-115.

See Also

blur_ratio, cross_correlation

Other test sound alignment: align_test_files(), find_markers(), manual_realign(), plot_aligned_sounds()

Examples

{
  # load example data
  data("test_sounds_est")
  data("master_est")
  
  # create "unaligned_test_sounds_est" by
  # adding error to "test_sounds_est" start and end
  unaligned_test_sounds_est <- test_sounds_est
  set.seed(123)
  noise_time <- sample(c(0.009, -0.01, 0.03, -0.03, 0, 0.07, -0.007),
  nrow(unaligned_test_sounds_est),
  replace = TRUE)
  
  attr(unaligned_test_sounds_est, "check.res")$start <- 
  unaligned_test_sounds_est$start <- 
  unaligned_test_sounds_est$start + noise_time
  attr(unaligned_test_sounds_est, "check.res")$end <- 
  unaligned_test_sounds_est$end  <- 
  unaligned_test_sounds_est$end + noise_time

# re align
realigned_est <- auto_realign(X = unaligned_test_sounds_est, Y = master_est)
}

maRce10/baRulho documentation built on March 30, 2024, 7:50 a.m.