red on black aavso charts, R

library(dplyr)
library(magick)

red_on_black <- function(image) {
    image %>%
        image_negate() %>%
        image_transparent("white", fuzz = 75) %>%
        image_background("red", flatten = TRUE) -> dark_image
    return(dark_image)
}

chart <- image_read("numele_fisierului_salvat_de_pe_aavso.png")
red_chart <- red_on_black(chart)
image_write(red_chart, "rosu_pe_negru.png")