Glad it worked out for you—it seemed like the features are there for basic image conversion, but try to do something a little more sophisticated and you run into some severe design limits. Here is the kind of underlying problem I’m talking about:
Why would you do something more sophisticated though, versus just using your own pixel data structures and the converting if/when you want to load/save. This is supposed to be a stand-in for image magic, not a panacea for doing image processing in Rust. Maybe start an image-processing crate if that is your interest?
https://github.com/image-rs/image/issues/1523