miniGRIP v19.7.12 www.grelf.net
A few things should be noted:
So far the only processing offered is to invert the contrast, to make a negative image. It is planned to extend this to offer image resizing and some other simple processes. Browsers do limit the time available for processing though.
In a sense this is like a tiny, tiny version of the powerful image processor, GRIP, that I developed in Java from 2004 onwards.