FreeImage is a library project for developers who would like to support popular graphics image formats (PNG, JPEG, TIFF, BMP and others). Some highlights are: extremely simple in use, not limited to the local PC (unique FreeImageIO) and Plugin driven!
XPaint is a simple paint program for X, suitable for producing simple graphics. It does offer some advanced features such as image processing functions and gradient fill. XPaint was originally written by David Koblas.
Standalone software for photo editing and digital painting.
NOTE: Source code is no longer available. GeniuX® Photo EFX is a standalone software for photo editing and digital painting, powerful and easy to use. It can load RAW files of reflex digital cameras and is fully compatible with Adobe Photoshop. The previous version of this software counts more than 800.000 entries on Google search engine and is officially approved on Adobe Inc marketplace. Completely designed and produced in Italy, GeniuX® Photo EFX stands out for its 32 bit color graphic engine: it assures refined digital color gradations which allows to obtain bright prints of the highest quality, especially for skin color handling. The interface is conceived to highlight the most popular tools, for example black and white management, professional color processing, noise removal, photomontage and background removal.
Graphic edtor for J2ME platform.
PhoXo Core Library (PCL) is a set of powerful image manipulation library for C++, it's OS independent and highlights are : Undo/Redo,multiple-layer,region selection,tens of image effect...
Transparency is a small tool for transparent PNG processing on the command line. It provides conversion of white to transparency, and the preparation of transparent PNGs for perfect GIF export (i.e., "partial" application of the alpha channel).