R/addNoiseToImage.R

In stnava/ANTsR: ANTs in R: Quantification Tools for Biomedical Images

#' addNoiseToImage
#'
#' Add noise to image using additive Guassian, salt-and-pepper,
#' shot, or speckle noise.
#'
#' @param image input image
#' @param noiseModel either "additivegaussian", "saltandpepper", "shot",
#' or "speckle".
#' @param noiseParameters vector defining the noise models.
#' \code{additivegaussian}: (mean, standardDeviation),
#' \code{saltandpepper}: (probability, saltValue, pepperValue),
#' \code{shot}: (scale),
#' \code{speckle}: (standardDeviation),
#' @return noise corrupted image.
#'
#' @author NJ Tustison
#'
#' @examples
#' image <- antsImageRead(getANTsRData("r16"))
#' noiseImage <- addNoiseToImage(image, "additivegaussian", c(0, 1))
#' noiseImage <- addNoiseToImage(image, "saltandpepper", c(0.1, 0, 100))
#' noiseImage <- addNoiseToImage(image, "shot", c(1.0))
#' noiseImage <- addNoiseToImage(image, "speckle", c(1.0))
#'
#' @export addNoiseToImage

addNoiseToImage <- function(
    image,
    noiseModel = c("additivegaussian", "saltandpepper", "shot", "speckle"),
    noiseParameters) {
  whichNoiseModel <- -1
  noiseModel <- match.arg(noiseModel)
  if (noiseModel == "additivegaussian") {
    whichNoiseModel <- 0L
    if (length(noiseParameters) != 2) {
      stop("Error:  incorrect number of parameters.")
    }
  } else if (noiseModel == "saltandpepper") {
    whichNoiseModel <- 1L
    if (length(noiseParameters) != 3) {
      stop("Error:  incorrect number of parameters.")
    }
  } else if (noiseModel == "shot") {
    whichNoiseModel <- 2L
    if (length(noiseParameters) != 1) {
      stop("Error:  incorrect number of parameters.")
    }
  } else if (noiseModel == "speckle") {
    whichNoiseModel <- 3L
    if (length(noiseParameters) != 1) {
      stop("Error:  incorrect number of parameters.")
    }
  } else {
    stop("Error:  unrecognized noise model.")
  }

  outputImage <- ANTsRCore::addNoiseToImageR(
    antsImageClone(image),
    whichNoiseModel,
    as.numeric(noiseParameters)
  )
  return(outputImage)
}