createOctaveLevel: Create Octave Level Measurements

In PAMscapes: Tools for Summarising and Analysing Soundscape Data

Create Octave Level Measurements

Description

Creates (third) octave level or broadband measurements from finer resolution soundscape metrics, like Power Spectral Density (PSD) or Hybrid Millidecade (HMD) measures

Usage

createOctaveLevel(
  x,
  type = c("ol", "tol", "broadband", "bb"),
  freqRange = NULL,
  normalized = FALSE
)

Arguments

x	dataframe of soundscape metrics
type	one of 'ol' to create octave level, 'tol' to create third octave level measures, or 'broadband' or 'bb' to create an arbitrary broadband measure. For broadband measures, freqRange must be supplied to define the range
freqRange	a vector of the minimum and maximum center frequencies (Hz) desired for the output. If NULL, full available range of frequencies will be used. If output type is broadband, this is used to define the lower and upper bounds of the desired output broadband level
normalized	logical flag to return values normalized by the bandwidth of each octave level band (per Hz)

Details

To create new measurements, finer resolution metrics are cast to linear space, summed, and then re-logged. If input measurements are HMD values then they are assumed to be normalized per Hz, so levels are first corrected by the bandwidth before summing. In all other cases inputs are assumed to not be normalized per Hz measurements and are just summed.

Value

a dataframe with summarised octave level band measurements

Author(s)

Taiki Sakai [e-mail]

Examples

psd <- loadSoundscapeData(system.file('extdata/PSDSmall.csv', package='PAMscapes'))
str(psd)
tol <- createOctaveLevel(psd, type='tol')
str(tol)
ol <- createOctaveLevel(tol, type='ol')
str(ol)
bb <- createOctaveLevel(psd, type='bb', freqRange=c(20, 150))
str(bb)

PAMscapes documentation built on April 4, 2025, 2:17 a.m.