In this mini-guide I have hand-picked the best downloadable free picture editing programs. And what is best, some of these image editing tools are cross-platform, making them available for PCs, Macs and Linux computers.
1. Gimp
GIMP is a powerful free picture editing software released under GNU license. You can use GIMP to retouch your photos, create logos for your website, author your images, and much more. GIMP comes packed with advanced features like filters, layers, and everything you use in professional software like Adobe Photoshop. Available for Windows, Mac Os X, Linux, and Solaris.
2. GIMPshop
GIMPshop is a modified version of the popular open-source picture editing software GIMP. Similarly released under the GPL license, GIMPshop is a valuable alternative to a more complex solution like Photoshop. In fact, GIMPshop modifies the layout structure of your images to closely match the popular Adobe software interface. It works on Windows, Mac OS X, and Linux.
3. Phantasmagoria
Phantasmagoria is a free Java-based image editor that runs on Windows, Mac Os X and Linux. It supports a wide range of image formats, and lets you easily edit and improve your images with a lot of effects. You can create graphics, including textures and highly-stylized text and, when you are done, you can export your pictures to Flickr.
4. ImageMagick
ImageMagick is a free utility for converting, editing, and composing images. ImageMagick can batch convert all of your images in a matter of seconds, without having to manually process them in Photoshop, or another image editor. Besides changing file format, you can also flip, mirror, rotate, scale, adjust colors, apply effects, draw text and lines. Available for Windows, Mac Os X and Linux.
5. PhotoFiltre
PhotoFiltre is a free image editor software that helps you to edit and retouch your photos. PhotoFiltre has its main strength in its easiness of use. Sharpen, add brightness, contrast or crop your images is as easy as pressing a button. Very good for quick tasks where you don't need a more professional solution. Windows only.
6. Paint.NET
Paint.NET is a free image editing software for Windows machines. Originally intended as a free replacement for the Microsoft Paint software, Paint.NET is a complete solution whose features include support for layers, unlimited undo, special effects, and much more. Available in several languages.
7. FastStone Image Viewer
FastStone Image Viewer is a free image browser, converter and editor. Its features include image viewing, management, comparison, red-eye removal, emailing, resizing, cropping and color adjustments. The software also provides access to EXIF information, and supports all major graphic formats and popular digital camera RAW formats. Windows only.
