I'm building a client-side-only web page that will (eventually) allow users to build their own image filter and batch-apply it to a bunch of images.

https://kaliedarik.github.io/sc-filter-builder/

No idea if anyone will be interested in using such a (free, MIT) web tool, but I'm having lots of fun putting my canvas library's filter engine (which is inspired by SVG chainable filters) through its paces.