Gimp

GIMP (GNU Image Manipulation Program) is a freely distributed piece of software suitable for such tasks as photo retouching, image composition, and image authoring. It is a powerful piece of software with capabilities not found in any other free software product. It can be used as a simple paint program, an expert-quality photo-retouching program, an online batch-processing system, a mass production image renderer, or an image-format converter. GIMP is modular, expandable, and extensible. It is designed to be augmented with plug-ins and extensions to do just about anything. The advanced scripting interface allows everything from the simplest task to the most complex image-manipulation procedures to be easily scripted.
Gimp is a free user friendly photo Editor and its distributed on all the platform of OS’s. One of the most powerful general-purpose image editors around, the upgrades make the GNU Image Manipulation Program eminently comparable to Photoshop. Older features include channels, layers and masks, filters and effects, tabbed palettes, editable text tools, perspective clone, improved printing, and color operations such as levels. New improvements include GEGL integration for 32-bit color support, dynamic brushes, and more options for the free select tool. It even has regex-based pattern matching for power users.


It runs on all platforms even on Mac Linux and Windows...!