crabs_tutorial: Does not matter.

library(magick)
library(magrittr)
library(stringr)

# copy the existing .png to raw prefix images

all_images <- list.files('images', pattern = "*.png")
new_names <- paste0("raw_", all_images)

file_location <- paste("images\\",all_images, sep = "")
new_file_location <- paste("images\\",new_names, sep = "")

file.rename(file_location, new_file_location )

# for (i in (1:length(new_file_location))){
#   print(i)
#   input_img <- image_read(new_file_location[i])
#   output_img <- image_shadow(input_img, color = "black", bg = "white", geometry = "50x10+30+30", operator = "atop", offset = "+20+20")
#   image_write(output_img, file_location[i])
# }


all_raw_images <- list.files('images', pattern = "raw_")
for (image in all_raw_images){
  filelocation <- paste("images\\",image, sep = "")
  shadow_bordered_img <- image_read(filelocation) %>% image_shadow(color = "black", bg = "white", geometry = "50x10+30+30", operator = "atop", offset = "+20+20")
  newfilelocation <- str_remove(filelocation, "raw_")
  image_write(shadow_bordered_img, newfilelocation)}