fft_filter: Apply fft filter

Description Usage Arguments Value Examples

View source: R/utils.R

Description

Apply fft filter

Usage

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fft_filter(im, xpass, kernel = "ideal", cutoff, cutoff2, order = 4)

Arguments

im

an image

xpass

either "lowpass", "highpass", or "bandpass"

kernel

either "ideal", "gauss", "butterworth", or "dc"

cutoff

cutoff frequency

cutoff2

second cutoff frequency

order

order of butterworth filter

Value

an image

Examples

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plot(fft_filter(regatta, "lowpass", "ideal", 10)) # ideal lowpass filterig
plot(fft_filter(regatta, "lowpass", "gauss", 10)) # gaussian lowpass filterig
# 5th-order butterworth lowpass filtering
plot(fft_filter(regatta, "lowpass", "butterworth", 10, order = 5))
im = im_gray(regatta)
plot(fft_filter(im, "highpass", "gauss", 60), rescale = TRUE) # gaussian highpass filterig
plot(fft_filter(im, "bandpass", "gauss", 10, 20), rescale = TRUE) # gaussian bandpass filterig

tsuda16k/noesis documentation built on Nov. 25, 2020, 10:16 a.m.