Autothumb plugin

Hi.
I would like to add some filter to my photos like: sepia, b&w, crop, or rounded conners.
I found autothumb plugin as a best result but i don’t know exactly how to use it.
I’ve install and active plugin, but i don’t understand what to do next.
How to use custom fields and what should it be in value?
I use also use thumb support from 2.9 version and use pictures as thumb