README.md

In davesteps/imageFF: Performs pie-slice filtering of fourier transforms of images

imageFF

Functions for applying 'pie-slice' filters to fourier transforms of images.

I wrote the functions to remove stripe noise from acoustic data, in the spirit of this paper:

Application of 2D Fourier filtering for elimination of stripe noise in side-scan sonar mosaics

install:

If you don't have devtools install it, then the package from github:

if (!require("devtools"))
  install.packages("devtools")
devtools::install_github("imageFF", "davesteps")

Usage:

n <- nrow(volcano)
signal <- 20*(sin(2*pi*(1:n)/15)) +30*(sin(2*pi*(1:n)/10))
plot(signal,type='l')
image(volcano)
image((volcano+signal))
#plot fourier transform
plotFF(volcano+signal)
#apply pie slice filter
rFF <- imageFF(volcano+signal,d = 90,l = 0.5,t = 5,lwl_buf=T,bd=0.025)
image(volcano)
image(rFF)
hist(((rFF-data)/data)[])
plot(volcano,rFF)

davesteps/imageFF documentation built on May 14, 2019, 9:01 p.m.