callsync (version 0.2.3)

sliding.pixel.comparison: sliding.pixel.comparison

Description

Can be used to run spectrographic cross correlation. Both spectrograms are zero-padded and slid over each other. For each step the difference is computed. The function returns the absolute difference at the point at the minimum (maximal signal overlap).

Usage

sliding.pixel.comparison(s1, s2, step_size = 1)

Value

Returns the distance at the point of maximal signal overlap.

Arguments

s1

numeric matrix, the first spectrogram.

s2

numeric matrix, the second spectrogram.

step_size

numeric, how many pixels should be moved for each step. Default is `1`.

Examples

require(callsync)
require(seewave)
require(tuneR)
path_git = 'https://raw.githubusercontent.com'
path_repo = '/simeonqs/callsync/master/tests/testthat/files'
file_1 = '/wave_1.wav'
file_2 = '/wave_2.wav'
url_1 = paste0(path_git, path_repo, file_1)
url_2 = paste0(path_git, path_repo, file_2)
local_file_1 = paste(tempdir(), file_1, sep = '/')
local_file_2 = paste(tempdir(), file_2, sep = '/')
if(!file.exists(local_file_1))
  download.file(url_1, destfile = local_file_1, mode = 'wb',)
if(!file.exists(local_file_2))
  download.file(url_2, destfile = local_file_2, mode = 'wb')
wave_1 = readWave(local_file_1)
wave_2 = readWave(local_file_2)
so_1 = create.spec.object(wave = wave_1, plot_it = FALSE)
so_2 = create.spec.object(wave = wave_2, plot_it = FALSE)
out = sliding.pixel.comparison(so_1, so_2)