Appendix A — Putting it all together

Setup

library(webmorphR) # for image manipulation
library(gifski) # for animation

wm_opts(plot.maxwidth = 850*2)

A.1 Read in images

Read in the images. I named them stupidly, without leading 0s, so am importing them in two batches: the ones with one digit after “day”, then the ones with two digits after “day”.

Code

imgs <- c(
  read_stim("images", "day\\d{1}\\.(png|gif)"),
  read_stim("images", "day\\d{2}\\.(png|gif)")
)

There are two of “day15”, so I’ll get rid of the first.

Code

imgs <- imgs[c(1:15, 17:31)]

A.2 Flatten gifs

Some of the images are animated gifs, so I have to flatten them.

Code

multi_img <- sapply(width(imgs), length) > 1

imgs[multi_img] <- imgs[multi_img] %>% image_func("flatten")

# fix width and height
for (i in seq_along(imgs)) {
  imgs[[i]]$width <- imgs[[i]]$width[[1]]
  imgs[[i]]$height <- imgs[[i]]$height[[1]]
}

A.3 Resize images

Next, I need to resize the images all to the same size. The to_size() function is a combination of crop(), pad() and resize() that gets all images as large as possible, centered in the image.

Code

resized <- to_size(imgs, width = 600, height = 600)

A.4 Add labels

Code

chapters <- list.files(".", pattern = "^\\d{2}-.+\\.qmd")
names <- gsub("(^\\d+-|\\.qmd$)", "", chapters)
names <- gsub("-", " ", names) |> stringr::str_to_title()
names[names=="Owid"] <- "OWID"
names[names=="Oecd"] <- "OECD"
names[names=="Un Population"] <- "UN Population"

labelled <- resized %>%
  pad(top = 100, 0, 0, 0) %>%
  label(names, gravity = "north", location = "+0+0")

Code

plot_stim(labelled, nrow = 5)

A.5 Make animation

Code

anim <- labelled %>%
  pad(0, 10, 10, 10) %>%
  animate(fps = 1)

write_stim(anim, dir = "images", names = "debruine_30DCC", format = "gif")

knitr::include_graphics("images/debruine_30DCC.gif")