Shrink file size of a PNG

This does not change size of the image in pixels, nor does it affect appearance -- it is lossless compression. This requires the program optipng to be installed.

shrink(filename)

Arguments

filename

Character vector containing the path of images to resize. Must be PNG files.

Value

The `filename` supplied but with a class value of `"webshot"`.

Details

If other operations like resizing are performed, shrinking should occur as the last step. Otherwise, if the resizing happens after file shrinking, it will be as if the shrinking didn't happen at all.

Examples

if (interactive()) {
  webshot("https://www.r-project.org/", "r-shrink.png") %>%
    shrink()
}