Hi, I saw a post about this and your note about future micropython support!
I've been using OpenMV for years now within the micropython ecosystem and they have a lot of very highly optimised c based image processing libraries with first class micropython support; it would be worth learning from them as much as possible to avoid too much duplication of effort.

The lvgl project is another C library with great micropython support; I bring them up as the micropython bindings there are auto-generated from the C code via tooling in https://github.com/lvgl/lv_binding_micropython / https://blog.lvgl.io/2019-08-05/micropython-pure-display-driver
Their tooling is certainly customised for their project but it greatly reduces the maintenance burdon for the micropython bindings which I think would be a worthy goal for projects like this one.