bioacoustic_index {soundecology}

Bioacoustic Index

Description

Bioacoustic Index from Boelman, et al. 2007. Inspired on Matlab code courtesy of NT Boelman. Several parts where changed, in particular log math, so this won't be directly comparable to the original code in the paper.

The Bioacoustic Index is calculated as the "area under each curve included all frequency bands associated with the dB value that was greater than the minimum dB value for each curve. The area values are thus a function of both the sound level and the number of frequency bands used by the avifauna" (Boelman, et al. 2007).

Usage

bioacoustic_index(soundfile, min_freq = 2000, max_freq = 8000, fft_w = 512)

Arguments

soundfile

an object of class Wave loaded with the function readWave of the tuneR package.

min_freq

minimum frequency to use when calculating the value, in Hertz.

max_freq

maximum frequency to use when calculating the value, in Hertz.

fft_w

FFT window size.

Value

Returns a list with one object per channel

left_area

area under the curve for the left channel

right_area

area under the curve for the right channel

References

Boelman NT, Asner GP, Hart PJ, Martin RE. 2007. Multi-trophic invasion resistance in Hawaii: bioacoustics, field surveys, and airborne remote sensing. Ecological Applications 17: 2137-2144.

Examples

	data(tropicalsound)
	bioindex <- bioacoustic_index(tropicalsound)
	print(bioindex$left_area)
	
	summary(bioindex)