Welcome to this Treasure Chest of Free Stuff.Here is a program that comes from an open source community that is committed to refining and improving it. This is listed on the Productivity page, and if you need to edit images, this may well be all you need.

GIMP (downloadable program) “The GIMP” (GNU Image Manipulation Program) is powerful free open source software designed for editing images. You can use it as a simple paint program, to do serious photo retouching, or for a host of more sophisticated and specialized editing tasks. The user interface of the latest version of The GIMP has made the program relatively easy to work with, but it still requires either past experience with photo editing or a significant learning curve. Fortunately, there is an extensive online manual. There are also helpful tutorials available from the GIMP community as well, and these are designated by level as beginner, intermediate, expert, and beyond. To lean more, for the support materials as well as for instructions on downloading, go to http://www.gimp.org/

The Gimp is cross-platform: Windows, Mac, Linux.