Attachment_fu: save to a default format

Resizing is a basic feature, take a look at the README. Format transformation, on the other hand, is more difficult and is not a known feature of attachemnt_fu...

Cheers, Sazima

Here’s an example of how to do what you want with Rmagick (probably works in principle with mini magick, but not sure):

It’s a module we mix in to monkey patch (i.e. redefine methods locally) attachment_fu’s built in processor code for Rmagick in the Kete app (

Cheers, Walter