R/fcis.R

In edwbaker/SonicScrewdriveR: Bioacoustic Analysis and Publication Tools

scaleRGB <- function(vector, no.diff=255) {
  if (length(unique(vector)) == 1) {
    return(rep(no.diff, length(vector)))
  }
  vector <- as.numeric(vector)
  vector <- (255 / (max(vector) - min(vector))) * (vector - min(vector))
  vector[is.na(vector)] <- 0
  return(as.integer(vector))
}

#' Map three vectors to RGB
#'
#' Maps three vectors of equal length to RGB for use in false-colour index
#' spectrograms
#' @param red The red channel vector
#' @param green The green channel vector
#' @param blue The blue channel vector
#' @return A vector of RGB values
#' @export
map2RGB <- function(red, green, blue) {
  red <- scaleRGB(red)
  blue <- scaleRGB(blue)
  green <- scaleRGB(green)
  return(rgb(red, green, blue, maxColorValue=255))
}