There is a couple of options for reading images in tiff format into R, including library(tiff), but also library(magick), library(terra) (as the successor of raster) and library(EBImage).
I would only like to down-scale/downsample the original tiff images to a lower resolution for later ggplot output to PDF.
Which would be the simplest, most portable (across operating systems) way with the fewest dependencies?
Intuitively, I would assume that actually library(grid) would be the most basic and native version (which I probably do already depend on for ggplot output anyway), but I'm not sure whether it provides functionality for scaling.