ASCII Art with Imager for Fun

Ascii Art

library(tidyverse)
library(imager)

## Following http://dahtah.github.io/imager/ascii_art.html


img_url <-"https://live.staticflickr.com/65535/50916479098_dc9f441e76_c.jpg"

im_orig <- load.image(img_url) 
im_orig %>% plot()

## How big is my Data Frame going to be in terms of number of rows...
dim(im_orig)[1]*dim(im_orig)[2]  ## since my image is 800x800 px...If I convert image to data frame, it will be pretty big dataframe...  

## I want bit smaller image so that data frame is not going to be HUGE!
desired_x <- 100
scale_factor <- desired_x/((dim(im_orig)[1]))
im <- im_orig %>% imresize(scale=scale_factor)
#dim(im)[1]*dim(im)[2] 

## Test to make sure it's still visible
im %>% plot()


## Function to Convert Character Image to Average of Value
chr_darkness <- function(chr) {
  implot(imfill(50,50,val=1),text(25,25,chr,cex=5)) %>%
    grayscale() %>% mean()
}


## Type in the text you want to use in illustration below. 
chrs_to_use <- str_split("RStat*&%$#!",pattern="") %>% unlist() %>% unique()

## Create Alphabet Data Frame 
alphabet_df <- tibble(
  chr=chrs_to_use
) %>% mutate(darkness=map_dbl(chr,chr_darkness)) %>%
  mutate(d_rank = row_number(darkness))

## Just to view what letter will be used 
## You see letter with more ink on left and less ink on top right
alphabet_df %>% 
  ggplot(aes(x=d_rank,y=darkness)) +
  geom_text(aes(label=chr)) +
  theme_minimal() +
  labs(title="Darkest Alphabet to Lightest Alphabet in Value")



## convert cimg to dataframe with rgb value then using rgb value conver to hex
im_df_color <- im  %>% as.data.frame(wide="c") %>%
  mutate(hex=pmap_chr(list(red=c.1,green=c.2,blue=c.3),rgb))
## create gray scale version of data frame too
im_df_gray <- im %>% grayscale()  %>% as.data.frame()


## For this particular image, I'm just going to remove any "white part".
im_df_comb <- bind_cols(im_df_color, im_df_gray %>% select(value)) %>%
  filter(hex!="#FFFFFF")

## Join with Alphabet Data Frame to assign characters for value 
im_df_comb <- im_df_comb %>% 
  mutate(qv = scales::rescale(value,to=c(1,max(alphabet_df$d_rank))) %>% round()) %>%
  inner_join(alphabet_df %>% select(chr, qv=d_rank))


im_df_comb %>% ggplot(aes(x=x,y=y)) +
  geom_text(aes(label=chr, alpha=value, color=hex, size = value, family="Helvetica"), 
            data = . %>% filter(chr!="*")) +
  scale_y_reverse() +
  scale_color_identity() +
  coord_fixed() +
  theme_void() +
  scale_alpha_continuous(range=c(0.7,1), guide="none")+
  scale_size_continuous(range=c(5,10), guide="none")

## You can save the art 
ggsave("Downloads/Chicken.svg", width=16, height=16)
ggsave("Downloads/Chicken.png", width=16, height=16)