tdemin
commented
3 years ago I wonder if this is still the scope of this project, and not a Makefile directive (or whichever tool you prefer, might be Nix, Taskfile, etc) for build automation. Passing fd '.[png|jpeg|jpg|tif]' | xargs -n1 dither requires much less effort and fits, say, Unix ideology (do one thing and do it well).
Sadly, this would require dither to implement a command-line wrapper to the library.
PS: there's also of course a point to be made that Hugo implements a resource system, but I wonder how much of a maintenance burden it's going to add in, provided Hugo does quite a lot with it: language preprocessing, fingerprinting, image conversion, etc...
mntn-xyz
Perhaps this is better for a plugin, or another program entirely, but I got this idea after seeing the Gemini "imageboard" someone just made (iich.space/img) and I couldn't help but share it.
What if there were an option to either generate dithered "preview" images (or to replace the images entirely) via this library: https://github.com/makeworld-the-better-one/dither
I'm more partial to generating preview images, because some things like technical diagrams wouldn't work so well with dithering. But I can imagine that people running their Gemini sites on low bandwidth/low power servers might want the option to shrink all their images.